Ammonium styrenesulfonate composition having excellent storage stability and method for producing same

Abstract

Provided are: an ammonium styrenesulfonate composition having excellent long-term storage stability; and a simple method for producing the ammonium styrenesulfonate composition in consideration of the environment. The ammonium styrenesulfonate composition has the following characteristics (1)-(6). (1) the content of ammonium styrenesulfonate in the composition is 88.0 wt% or more; (2) the content of water in the composition is 10.00 wt% or less; (3) the alkali metal content in the composition is 0.50 wt% or less; (4) the halogen content in the composition is 1.00 wt% or less; (5) the polymer content in the composition is 0.20 wt% or less; and (6) the polymerization inhibitor content in the composition is 2000 ppm or less; and a production method using the ammonium styrenesulfonate composition.

Description

TECHNICAL FIELD

[0001] The present application relates to an ammonium styrene sulfonate composition which is excellent in storage stability, in which the decrease in purity and coloring caused by natural polymerization are inhibited upon long-term storage, and a simple production method thereof. BACKGROUND

[0002] Sodium styrene sulfonate is a water-soluble monomer of a strong electrolyte type having surface activity, and is excellent in heat resistance and radical polymerizability, and thus is used in a wide range of industrial fields.

[0003] For example, sodium styrene sulfonate has been used as a reactive emulsifier in the production of an acrylic emulsion for water-based paints and water-based adhesives. The reason for this is that, when radical polymerizable monomers such as acrylate and methacrylate are subjected to emulsion polymerization, the amount of addition of a conventional emulsifier is reduced, and instead, a small amount of sodium styrene sulfonate is added, and copolymerization is performed, whereby the colloidal stability of the polymer emulsion, the water resistance of the emulsion coating film, and the adhesion are improved.

[0004] However, when the amount of addition of sodium styrene sulfonate is increased in order to further improve the colloidal stability, adverse conditions such as a decrease in water resistance of the emulsion coating film, corrosion of iron nails and the like used in wooden buildings, and the like caused by sodium metal sometimes occur (for example, Non-Patent Literature 1). Therefore, the anionic emulsifier used in the production of an acrylic emulsion is mostly an amine salt which is a non-metallic salt (for example, Patent Literature 1 and Patent Literature 2).

[0005] In addition, polystyrene sodium sulfonate, which is a polymer of sodium styrene sulfonate, is used in electronic material applications such as a dispersant for carbon nanotubes, a chemical mechanical polishing (CMP) slurry for semiconductor substrates, a cleaning agent after polishing, and the like (for example, Patent Literatures 3 to 5). However, in particular, in semiconductor applications, metal components and halogen components become a cause of defects and corrosion of substrates, and thus it is required to contain them as little as possible (for example, Patent Literature 6).

[0006] Therefore, it is more preferable to contain an ammonium salt of polystyrene sulfonic acid, which contains metal components and halogen components as little as possible.

[0007] In view of the above background, there is a strong market demand for ammonium styrene sulfonate, and in order to meet this demand, a production method thereof has been proposed (for example, Patent Literatures 7 and 8, and Non-Patent Literature 2).

[0008] In Patent Literature 7, for example, sodium styrenesulfonate and ammonium sulfate are dissolved in methanol at 60°C, a cation exchange reaction is performed, and then the solution is cooled to 30°C, whereby sodium sulfate generated by the cation exchange is precipitated. Then, the precipitated sodium sulfate is filtered off, and the methanol solution of the ammonium styrenesulfonate is recovered, and the methanol solution is further concentrated and dried, whereby ammonium styrenesulfonate solid is obtained. It is stated that the method utilizes the difference in solubility of the ammonium styrenesulfonate generated by the cation exchange and sodium sulfate in methanol.

[0009] However, the total reaction medium concentration is low, about 9% by weight, and it takes time to concentrate and dry, and thus polymers are easily generated during this period, and in addition, methanol used as the reaction solvent is toxic and flammable, and thus there are problems in safety. Also, in the method, high-purity ammonium styrenesulfonate is not necessarily obtained. The lower the dielectric constant of the solvent, the lower the degree of ion dissociation of the salt, and thus the cation exchange reaction is substantially difficult to perform in an organic solvent, and there is not a sufficient difference in solubility between sodium styrenesulfonate and ammonium styrenesulfonate in an organic solvent, and thus sodium cannot be avoided from remaining in the ammonium styrenesulfonate. In addition, in commercially available sodium styrenesulfonate, 2 to 3% by weight of sodium bromide as an impurity is generally contained, and the sodium bromide and ammonium bromide generated by the cation exchange of the sodium bromide and ammonium sulfate are dissolved in methanol, and thus bromine cannot be avoided from remaining in the ammonium styrenesulfonate.

[0010] In addition, the ammonium styrenesulfonate obtained in the above-described method has a problem of poor storage stability compared to sodium styrenesulfonate, which is a more serious problem in industrialization. As a reason, it is considered that a proper polymerization inhibitor is not added.

[0011] In Patent Literature 8, for example, p-toluidine hydrochloride is added to an aqueous solution of sodium styrenesulfonate, and after recovering the p-toluidine styrenesulfonate salt precipitated by the salt exchange, the p-toluidine salt is put into an aqueous ammonia solution, whereby the salt exchange is performed again, and an aqueous ammonium styrenesulfonate solution is obtained. However, p-toluidine, which is harmful and easily colored, is used, and in addition, the p-toluidine styrenesulfonate salt is soluble in water due to the ammonium styrenesulfonate, and thus p-toluidine cannot be avoided from being mixed in the ammonium styrenesulfonate. In addition, as in Patent Literature 7, when water is distilled off from an aqueous solution containing ammonium styrenesulfonate at a low concentration of about 10% by weight to precipitate ammonium styrenesulfonate crystals, polymers are easily generated, and a proper polymerization inhibitor is not added, and thus there is a large problem in long-term storage stability required for industrialization.

[0012] In Non-Patent Literature 2, the following subject is described: for example, by blowing hydrogen chloride gas into sodium styrene sulfonate dispersed in acetone, sodium styrene sulfonate is converted into styrene sulfonic acid soluble in acetone and sodium chloride insoluble in acetone, and after filtering out sodium chloride, an acetone solution of styrene sulfonic acid is recovered, and further neutralized with ammonia, thereby obtaining ammonium styrene sulfonate. However, there are problems that flammable organic solvents and toxic hydrogen chloride gas and ammonia gas are used, and also, due to hydrogen chloride remaining in the acetone solution of styrene sulfonic acid, it is not possible to avoid the mixing of ammonium chloride into ammonium styrene sulfonate. As a further important problem, styrene sulfonic acid as a reaction intermediate is extremely easy to naturally polymerize (also referred to as spontaneous polymerization, catalyst-free polymerization), and thus there is a problem that it is not possible to avoid the mixing of polymers (for example, Non-Patent Literature 3).

[0013] In light of the above background, ammonium styrene sulfonate has not been industrialized, and there is a strong demand for high-purity ammonium styrene sulfonate that balances storage stability and can be applied to the above-mentioned uses, and a manufacturing method of the ammonium styrene sulfonate that is simple and environmentally friendly.

[0014] Prior Art Documents

[0015] Patent Documents

[0016] Patent Document 1: Japanese Patent No. 3585588

[0017] Patent Document 2: Japanese Patent No. 3460246

[0018] Patent Document 3: Japanese Patent No. 5482194

[0019] Patent Document 4: Japanese Patent No. 6618355

[0020] Patent Document 5: Japanese Patent Application Laid-Open No. 2021-44537

[0021] Patent Document 6: International Publication No. 2020 / 184306

[0022] Patent Document 7: Japanese Patent Application Laid-Open No. Show 50-149642

[0023] Patent Document 8: Japanese Patent Application Laid-Open No. Show 51-26842

[0024] Non-Patent Literature

[0025] Non-Patent Literature 1: Jose M. Asua; European Polymer Journal, 2017, Vol. 93, pp. 480-494

[0026] Non-Patent Literature 2: Oriental Chemical Research Report, Vol. 24, No. 1, 1980, pp. 3-11

[0027] Non-patent literature 3: J. C. Salamone; Polymer Letters Edition, Vol. 15, 1977, p. 487-491 SUMMARY

[0028] PROBLEMS TO BE SOLVED BY THE INVENTION

[0029] The present invention was completed in view of the above-described background and problems, and provides an ammonium styrene sulfonate composition which has both long-term storage stability and high purity, and a manufacturing method of the ammonium styrene sulfonate composition which is simple and takes into account the environment, avoiding the use of harmful and dangerous organic solvents, gases, and the like.

[0030] SOLUTION TO THE PROBLEMS

[0031] The present inventors and others conducted intensive research, and as a result, found the following, thereby completing the present invention: By controlling the moisture content, the type and content of the polymerization inhibitor, and the specific metal component contained in the ammonium styrene sulfonate composition within specific ranges, the long-term storage stability, which was a problem in the past, was significantly improved; and by using an alkali metal styrene sulfonate, an inorganic ammonium salt, a specific polymerization inhibitor, and water as a solvent, and performing reaction crystallization under specific conditions, an ammonium styrene sulfonate composition which has excellent long-term storage stability can be manufactured in high purity without using harmful and dangerous organic solvents, gases, and without going through strong acidic conditions in which polymers are easily generated. Note that the styrene sulfonate described below is typically a para isomer, but includes position isomers such as meta isomers and ortho isomers, as is generally known.

[0032] That is, the present invention is the following.

[0033] [1] An ammonium styrene sulfonate composition having the following characteristics (1) to (6). (1) The content of ammonium styrene sulfonate in the composition is 88.0% by weight or more; (2) the content of water in the composition is 10.00% by weight or less; (3) the content of alkali metal in the composition is 0.50% by weight or less; (4) the content of halogen in the composition is 1.00% by weight or less; (5) the content of polymers in the composition is 0.20% by weight or less; and (6) the content of polymerization inhibitors in the composition is 2000 ppm or less.

[0034] [2] The ammonium styrene sulfonate composition according to item [1], wherein (1) to (6) below are satisfied. (1) The content of the ammonium styrene sulfonate in the composition is 88.0% by weight or more; (2) the content of water in the composition is 0.10 to 10.00% by weight; (3) the content of alkali metal in the composition is 0.50% by weight or less; (4) the content of halogen in the composition is 1.00% by weight or less; (5) the content of polymer in the composition is 0.20% by weight or less; and (6) the content of polymerization inhibitor in the composition is 20 to 2000 ppm.

[0035] [3] The ammonium styrene sulfonate composition according to item [1], wherein (1) to (6) below are satisfied. (1) The content of the ammonium styrene sulfonate in the composition is 94.00% by weight or more; (2) the content of water in the composition is 0.10 to 6.00% by weight; (3) the content of alkali metal in the composition is 0.50% by weight or less; (4) the content of halogen in the composition is 0.10% by weight or less; (5) the content of polymer in the composition is 0.20% by weight or less; and (6) the content of polymerization inhibitor in the composition is 20 to 1000 ppm.

[0036] [4] The ammonium styrene sulfonate composition according to any one of items [1] to [3], wherein the polymerization inhibitor is at least one selected from the group consisting of 2-methoxyphenol, 3-methoxyphenol, 4-methoxyphenol, 4-ethoxyphenol, 4-cyanophenol, 4-butoxyphenol, 3-ethoxyphenol, 2,5-dimethoxyphenol, 2,6-dimethoxyphenol, 2,6-di-tert-butylphenol, 2,4-di-tert-butylphenol, 2,6-di-tert-butyl-4-methylphenol, 4-tert-butylcatechol, hydroquinone, methylhydroquinone, 2-methoxyhydroquinone, tert-butylhydroquinone, N-nitrosophenylhydroxylamine ammonium salt, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl, 4-(2-hydroxypropoxy-3-(2-hydroxyethoxy))-2,2,6,6-tetramethylpiperidine-1-ol, 4-(3-hydroxypropoxy-2-(2-hydroxyethoxy))-2,2,6,6-tetramethylpiperidine-1-ol, and salicylic acid hydrazide.

[0037] [5] The ammonium styrene sulfonate composition according to any one of items [1] to [3], wherein the polymerization inhibitor is at least one phenolic compound selected from the group consisting of 2-methoxyphenol, 3-methoxyphenol, 4-methoxyphenol, 4-ethoxyphenol, 4-cyanophenol, 4-butoxyphenol, 3-ethoxyphenol, 2,5-dimethoxyphenol, and 2,6-dimethoxyphenol.

[0038] [6] The ammonium styrene sulfonate composition according to any one of items [1] to [3], wherein the amount of electric charge per unit mass is 0.020 μC / g to 0.200 μC / g.

[0039] [7] The ammonium styrene sulfonate composition according to any one of items [1] to [3], wherein the median particle diameter of the crystals in the composition is 30 μm to 700 μm.

[0040] [8] The ammonium styrene sulfonate composition according to any one of items [1] to [3], wherein the median particle diameter of the ammonium styrene sulfonate crystals is 30 μm to 500 μm.

[0041] [9] The ammonium styrene sulfonate composition according to any one of items [1] to [3], wherein the content of the polymer in the composition when the composition is stored in a closed state at 60°C for 60 days is 0.20% by weight or less.

[0042]

[10] The ammonium styrene sulfonate composition according to any one of items [1] to [3], wherein in a powder X-ray diffraction pattern measured by irradiation of copper Kα X-rays, diffraction peaks are present at least at diffraction angles 2θ = 8.1 ± 0.2°, 15.2 ± 0.2°, 18.4 ± 0.2°, 20.6 ± 0.2°, 24.2 ± 0.2°, 32.5 ± 0.2°, and 43.0 ± 0.2°.

[0043]

[11] The ammonium styrene sulfonate composition according to any one of items [1] to [3], wherein in a powder X-ray diffraction pattern measured by irradiation of copper Kα X-rays, diffraction peaks are present at least at diffraction angles 2θ = 8.1 ± 0.2°, 15.2 ± 0.2°, 15.4 ± 0.2°, 18.4 ± 0.2°, 20.1 ± 0.2°, 20.6 ± 0.2°, 20.8 ± 0.2°, 24.2 ± 0.2°, 25.8 ± 0.2°, 27.5 ± 0.2°, 30.5 ± 0.2°, 32.5 ± 0.2°, 37.5 ± 0.2°, 43.0 ± 0.2°, and 49.6 ± 0.2°.

[0044]

[12] A method for producing a styrene sulfonic acid ammonium salt composition according to any one of items [1] to [3], wherein, after a cation exchange reaction is performed by contacting sodium or potassium styrene sulfonate with an inorganic ammonium salt in water in the presence of a polymerization inhibitor in an amount of 7 mol% or less relative to the amount of the sodium or potassium styrene sulfonate, and then cooling is performed to precipitate crystals of the styrene sulfonic acid ammonium salt, the crystals are filtered off, wherein the loading ratio of the ammonium cation relative to the alkali metal styrene sulfonate is 1.50 equivalents to 3.00 equivalents, the total solid content in the reaction system is 25.00% by mass to 50.00% by mass, the temperature at which the sodium or potassium styrene sulfonate is contacted with the inorganic ammonium salt is 30°C to 80°C, and the temperature at which the crystals precipitated by the cooling are filtered off is 5°C to 30°C.

[0045]

[13] The method for producing a styrene sulfonic acid ammonium salt composition according to item

[12] , wherein, after a cation exchange reaction is performed by contacting sodium or potassium styrene sulfonate with an inorganic ammonium salt in water in the presence of a polymerization inhibitor in an amount of 7 mol% or less relative to the amount of the sodium or potassium styrene sulfonate, and then cooling is performed to precipitate crystals of the styrene sulfonic acid ammonium salt, the crystals are filtered off, wherein the loading ratio of the ammonium cation relative to the alkali metal styrene sulfonate is 1.50 equivalents to 3.00 equivalents, the total solid content in the reaction system is 25.00% by mass to 45.00% by mass, the temperature at which the sodium or potassium styrene sulfonate is contacted with the inorganic ammonium salt is 30°C to 80°C, and the temperature at which the crystals precipitated by the cooling are filtered off is 5°C to 30°C.

[0046]

[14] The method for producing a styrene sulfonic acid ammonium salt composition according to item

[12] , wherein, after a cation exchange reaction is performed by contacting sodium or potassium styrene sulfonate with an inorganic ammonium salt in water in the presence of a polymerization inhibitor in an amount of 5 mol% or less relative to the amount of the sodium or potassium styrene sulfonate, and then cooling is performed to precipitate crystals of the styrene sulfonic acid ammonium salt, the crystals are filtered off, wherein the loading ratio of the ammonium cation relative to the alkali metal styrene sulfonate is 2.00 equivalents to 2.50 equivalents, the total solid content in the reaction system is 35.00% by mass to 45.00% by mass, the temperature at which the sodium or potassium styrene sulfonate is contacted with the inorganic ammonium salt is 40°C to 60°C, and the temperature at which the crystals precipitated by the cooling are filtered off is 5°C to 20°C.

[0047]

[15] The method for producing a styrene sulfonic acid ammonium salt composition according to item

[12] , wherein the inorganic ammonium salt is at least one compound selected from the group consisting of ammonium chloride, ammonium sulfate, ammonium nitrate, and ammonium acetate.

[0048] Effects of the Invention

[0049] The ammonium styrene sulfonate composition of the present application can be produced without using a hazardous and harmful raw material, without passing through an unstable intermediate, and by optimization of the composition, a decrease in purity upon long-term storage, which is an obstacle to industrialization, and coloring are significantly reduced, and thus are extremely useful for the production of an acrylic emulsion, the production of an ammonium styrene sulfonate polymer for electronic materials. Furthermore, the ammonium styrene sulfonate composition of the present application is dissolved in a polar organic solvent, and thus is extremely useful for the production of an electrolyte membrane, the modification of a polymer substrate by graft polymerization. BRIEF DESCRIPTION OF DRAWINGS

[0050] Figure 1 is a schematic view of a wet crystal (composition) of AmSS.

[0051] Figure 2 is a proton nuclear magnetic resonance spectrum chart of the AmSS composition obtained in Example 1. The horizontal axis indicates a chemical shift (ppm), and the numerical values in the four decimal places in the lower part of the chart indicate integral ratios of protons bonded to each carbon atom. Ha ~ He in the structural formula correspond to Ha ~ He near each peak, and the peak near 3 ppm corresponds to a methyl proton of dimethyl sulfone added as an internal standard.

[0052] Figure 3 is an optical microscope photograph (magnification 100 times) of the AmSS composition obtained in Example 1. In the photograph, the scale indicated by the blue line represents 250 μm.

[0053] Figure 4 is an optical microscope photograph (magnification 100 times) of the AmSS composition before drying obtained in Example 5. In the photograph, the scale indicated by the blue line represents 250 μm.

[0054] Figure 5 is a proton nuclear magnetic resonance spectrum chart of AmSS obtained in Comparative Example 11, and the numerical values in the chart are the same as Figure 2 .

[0055] Figure 6 is an optical microscope photograph (magnification 200 times) of AmSS obtained in Comparative Example 11. In the photograph, the scale indicated by the white line is 50 μm.

[0056] Figure 7 is a chart showing a powder X-ray diffraction pattern of the AmSS wet crystal obtained in Example 5. The vertical axis indicates a diffraction intensity (unit: counts), and the horizontal axis indicates a diffraction angle 2θ (unit: degrees), and the numerical values on the upper part of each peak in the chart indicate a detection angle of the peak top.

[0057] Figure 8 is an enlarged view (horizontal axis enlargement range: 10° ≤ 2θ ≤ 30°) of Figure 7 . The numerical values in the chart are the same as Figure 7 .

[0058] Figure 9 is a graph showing a powder X-ray diffraction pattern of the AmSS dried crystal (a crystal dried by using a rotary evaporator to dry the wet crystal) obtained in Example 5. The values in the graph are the same as those of Figure 7

[0059] Figure 10 is an enlarged view of Figure 9 (the horizontal axis enlargement range: 10°≤ 2θ ≤ 30°). The values in the graph are the same as those of Figure 7

[0060] Figure 11 is a graph showing a powder X-ray diffraction pattern of NaSS as a raw material used in Example 5. The values in the graph are the same as those of Figure 7

[0061] Figure 12 Figure 11 is an enlarged view of Figure 7

[0062] Figure 13 is a graph showing a powder X-ray diffraction pattern of the AmSS dried crystal (a crystal dried by using a rotary evaporator to dry the wet crystal) obtained in Example 6. The values in the graph are the same as those of Figure 7

[0063] Figure 14 Figure 13 is an enlarged view of Figure 7 DETAILED DESCRIPTION

[0064] Hereinafter, a mode for carrying out the present application (hereinafter referred to as "the present embodiment") will be explained in detail. Note that the present application is not limited to the following present embodiment. The present application can be carried out with appropriate modifications within the scope of the gist thereof.

[0065] First, the characteristics of the ammonium styrene sulfonate (hereinafter referred to as AmSS) composition of the present application will be explained in detail.

[0066] ​​​​​​​​Sodium styrenesulfonate (hereinafter referred to as NaSS) as a raw material of the AmSS composition of the present application is a powder-like vinyl monomer having extremely excellent storage stability, and no decrease in purity or coloring due to natural polymerization is observed for at least 3 to 4 years after production under storage at ordinary temperature. NaSS is produced by reacting 4-(2-bromoethyl)benzenesulfonic acid with sodium hydroxide in water as shown in the following scheme, but the anhydrous salt (anhydrous crystal) has the following problems: the crystal powder is solidified at ordinary temperature for about half a year to one year after production, or the purity is decreased due to natural polymerization.

[0067] Then, by converting the anhydrous salt of NaSS to a hemihydrate (hemihydrate crystal) by crystallization, it was found that the long-term storage stability was dramatically improved (for example, see Japanese Patent Application Laid-Open No. 10-152465). The NaSS currently in circulation is a hemihydrate having improved storage stability, and forms a stable crystal with two molecules of NaSS and one molecule of water, and in fact, in addition to the crystal water (theoretical value 4.4 wt%) contained therein, it also contains attached water (2 to 3 wt%) derived from the slurry filtrate (mother liquor), and thus the total moisture content in the product NaSS is usually 6 to 8 wt%. At the time of the above reaction, sodium nitrite or the like as a polymerization inhibitor is added, and a nitrous acid component of about 20 to 100 ppm remains in the product NaSS.

[0068]

[0069] On the other hand, ammonia has weak basicity, and AmSS cannot be produced directly from 4-(2-bromoethyl)benzenesulfonic acid and ammonia, and thus attempts have been made to produce AmSS from commercially available NaSS as described above. However, as described above, there are large problems in the production process such as the use of a hazardous and harmful raw material, the use of an unstable intermediate, a large number of steps, and reaction at a low substrate concentration, and industrialization has not been achieved.

[0070] Therefore, the present inventors and others have studied a simple and highly productive production method of AmSS using only water as a reaction solvent. As a result, it was found that when industrialized lithium styrenesulfonate (hereinafter referred to as LiSS), an inorganic ammonium salt, and a small amount of lithium nitrite or sodium nitrite are dissolved in water in a specific composition and then cooled, surprisingly, AmSS is preferentially crystallized to form a slurry, and by filtering the slurry, AmSS can be obtained extremely simply.

[0071] It is considered that the reason is that the solubility of AmSS in water is only about half of that of LiSS in water (see TOSOH FINECHEM Corporation homepage (https: / / www.tosoh-finechem.co.jp / )), and therefore AmSS is preferentially crystallized, and unreacted LiSS and other inorganic salts having high solubility remain in the mother liquor. However, there is a problem that the storage stability of the AmSS is poor, and even if stored at low temperature, a decrease in purity and coloring due to natural polymerization occurs within 1 to 2 months after production. As a reason, it is suggested that nitrite, which functions as a stabilizer for NaSS and LiSS, can not function for AmSS.

[0072] Therefore, the present inventors and others have investigated in detail factors that affect the storage stability of the above AmSS. As a result, it was found that the components and amounts of (1) to (3) below are important, and by controlling them within a certain range, a decrease in purity and coloring due to polymerization in long-term storage can be significantly inhibited.

[0073] (1) the content of water in the AmSS composition; (2) the kind and content of the polymerization inhibitor in the AmSS composition; and (3) the residual metal species and content in the AmSS composition.

[0074] Hereinafter, the characteristics of the AmSS composition of the present application are described in more detail.

[0075] That is, (1) the content of water in the AmSS composition is 10.00% by weight or less, and the less, the more preferable in terms of storage stability and fluidity, and more preferably 6.00% by weight or less, and particularly preferably 5.00% by weight or less. On the other hand, the less the content of water, the more likely to be charged, and the risk of scattering and dust explosion during handling increases, and a long drying process is required to reduce moisture as much as possible, and therefore practically, the content of water in the composition is 0.10% by weight or more.

[0076] (2) The content of the polymerization inhibitor contained in the AmSS composition depends on the kind of the polymerization inhibitor, but is usually 20 ppm or more, and more preferably 100 ppm or more. If the content of the polymerization inhibitor is less than 20 ppm, sufficient stability cannot be sometimes obtained. On the contrary, if the content of the polymerization inhibitor is too much, the polymerization rate, the degree of polymerization, and the color phase of AmSS when the AmSS composition is used are sometimes adversely affected, and therefore the content of the polymerization inhibitor is 2000 ppm or less, more preferably 1000 ppm or less, and further preferably 500 ppm or less.

[0077] (3) The coloring mechanism of the AmSS composition is not necessarily clear, and it is presumed to be related to the interaction with alkali metals such as lithium metal, nitrous acid, and a phenol-based polymerization inhibitor. At least the contents of lithium and nitrous acid are preferably less, and lithium is preferably 20 ppm or less, and usually 1 ppm or less, and the nitrous acid component is preferably 20 ppm or less. The nitrous acid component described herein is basically derived from sodium nitrite and lithium nitrite contained in NaSS and LiSS as raw materials, and is a nitrous acid anion that can be quantified by ion chromatography or the like.

[0078] In the present application, the purity of the AmSS composition is preferably 88.00% by weight or more, further preferably 94.00% by weight or more, and particularly preferably 95.00% by weight or more, and water is the main impurity, so the AmSS composition is forcibly dried or washed with a water-soluble organic solvent such as alcohol or acetone, and if the moisture is reduced, the purity will necessarily increase.

[0079] As the above-described polymerization inhibitor, there is no particular limitation as long as it is soluble in water or the reaction solution and inhibits the natural polymerization of AmSS, and examples include phenol-based polymerization inhibitors such as 2-methoxyphenol, 3-methoxyphenol, 4-methoxyphenol, 4-ethoxyphenol, 4-cyanophenol, 4-butoxyphenol, 3-ethoxyphenol, 2,6-dimethoxyphenol, 2,5-dimethoxyphenol, 4-isopropoxyphenol, 1,4-dihydroxy-2-methoxybenzene, hydroquinone, methylhydroquinone, 2-methoxyhydroquinone, 2,4-dinitrophenol, and the like; semi-hindered phenol-based polymerization inhibitors such as 4-tert-butylcatechol, butylated hydroxyanisole, tert-butylhydroquinone, and the like; hindered phenol-based polymerization inhibitors such as 2,6-di-tert-butylphenol, 2,4-di-tert-butylphenol, 2,6-di-tert-butyl-4-methylphenol, 2,5-di-tert-butylhydroquinone, and the like; stable nitroxyl radical-based polymerization inhibitors such as 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl, 4-(2-hydroxypropoxy-3-(2-hydroxyethoxy))-2,2,6,6-tetramethylpiperidin-1-ol, 4-(3-hydroxypropoxy-2-(2-hydroxyethoxy))-2,2,6,6-tetramethylpiperidin-1-ol, and the like; N-nitroso-N-phenylhydroxylamine ammonium salt, L-ascorbic acid, erythorbic acid, catechin, tocopherol, urea, and the like. Among these, from the viewpoints of compatibility with AmSS, solubility during the reaction, and color resistance, 2-methoxyphenol, 3-methoxyphenol, 4-methoxyphenol, 4-ethoxyphenol, 4-cyanophenol, 4-butoxyphenol, 3-ethoxyphenol, 2,5-dimethoxyphenol, 2,6-dimethoxyphenol, and 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl, 4-(2-hydroxypropoxy-3-(2-hydroxyethoxy))-2,2,6,6-tetramethylpiperidin-1-ol, 4-(3-hydroxypropoxy-2-(2-hydroxyethoxy))-2,2,6,6-tetramethylpiperidin-1-ol, which are the same aromatic compounds as AmSS, and polymerization inhibitors having high polymerization inhibition ability are more preferable. Sodium nitrite, lithium nitrite, and the like, which are nitrite-based polymerization inhibitors used in the production of NaSS and LiSS, sometimes adversely affect the color resistance of AmSS, and thus are preferably avoided.

[0080] In addition, the charged electric quantity per unit mass of the AmSS composition of the present application is 0.200 μC / g or less. The greater the charged electric quantity per unit mass exceeds 0.200 μC / g, the more easily the AmSS composition becomes charged, and the more the flying property and the dust explosion property during the handling operation increase. The securing of the storage stability is the most important, but by controlling the moisture content of the AmSS composition within the above-described range, both the low charging property and the high storage stability can be achieved.

[0081] While it does not directly affect the natural polymerization and colorability of AmSS, the median particle size of the AmSS crystals in the AmSS composition is preferably between 30 μm and 700 μm from the perspective of ensuring hygroscopic resistance, high fluidity, low dust emission, and dust explosion resistance. As described later, larger and thicker AmSS crystals are preferred because they improve deliquescence and enhance AmSS purity. However, excessively large crystals can sometimes reduce deliquescence, so a median particle size of 500 μm or less is more preferred. On the other hand, a median particle size of less than 30 μm significantly reduces deliquescence. Furthermore, even if the AmSS crystals after filtration or drying are large, mixing them with stirring or crushing them using a crusher or the like will disrupt and reduce the size of the crystals or crystal aggregates. Therefore, from the perspective of suppressing hygroscopicity, dust emission, and dust explosion resistance, the median particle size is preferably maintained at 30 μm or greater.

[0082] The AmSS composition of the present invention, when stored in a sealed state at 60°C for at least 60 days, has a polymer content of 0.20% by weight or less. Due to moisture control and the presence of an appropriate polymerization inhibitor, the composition exhibits extremely excellent storage stability. However, coloration of the AmSS composition due to oxidation of the AmSS or polymerization inhibitor is undesirable for applications such as coatings and adhesives where color is important. For example, the AmSS composition of the present invention, when stored in a sealed state at 60°C for 60 days, preferably has an APHA value of 100 or less when prepared as a 10% by weight aqueous solution.

[0083] The water content in the AmSS composition can be determined by 1 Quantification can be performed using H-NMR, a Karl Fischer titrator, a dry weight method using a constant temperature dryer, or an infrared titrator. Among these, an infrared titrator is the simplest and offers the best reproducibility.

[0084] The content, i.e., the purity, of the ammonium styrenesulfonate contained in the AmSS composition can be determined by quantification of the number of active vinyl groups by redox titration (e.g., see JP-A-2014-80505, paragraph 0055), proton nuclear magnetic resonance spectroscopy ( 1 H-NMR method), high performance liquid chromatography (HPLC) method, etc.

[0085] In passing 1 When quantification is performed by H-NMR, for example, the AmSS composition and a compound such as dimethyl sulfone as an internal standard are accurately weighed, dissolved in a deuterated solvent such as deuterated dimethyl sulfoxide, and measured. 1H-NMR. Then, the ammonium styrene sulfonate component in the AmSS composition can be quantified based on the ratio of the integral value of the methyl protons of dimethyl sulfone to the integral value of the protons derived from the styrene sulfonic acid skeleton, such as the vinyl protons. However, any of the above methods cannot distinguish between the alkali metal styrene sulfonate and the ammonium styrene sulfonate, and thus the molar ratio of the ammonium cation to the styrene sulfonic acid unit needs to be confirmed by elemental analysis, 1 H-NMR. Then, the ammonium styrene sulfonate component in the AmSS composition can be quantified based on the ratio of the integral value of the methyl protons of dimethyl sulfone to the integral value of the protons derived from the styrene sulfonic acid skeleton, such as the vinyl protons. However, any of the above methods cannot distinguish between the alkali metal styrene sulfonate and the ammonium styrene sulfonate, and thus the molar ratio of the ammonium cation to the styrene sulfonic acid unit needs to be confirmed by elemental analysis,

[0086] In the present application, the crystal shape of the obtained AmSS composition is generally a plate shape of a substantially circular or quadrangular shape, and the shape and size thereof can be measured using an optical microscope or an electron microscope. In the present application, the median particle diameter, which can be determined simply and reproducibly using a laser diffraction / scattering particle size distribution meter, is used. The laser diffraction / scattering particle size distribution meter calculates the particle diameter by regarding the sample as a spherical particle, and the median particle diameter refers to the diameter at which the sample is divided into two sides by a certain particle diameter, and the large side and the small side are equal in amount.

[0087] In addition, the content of the polymerization inhibitor in the AmSS composition can be quantified by gas chromatography (GC), high performance liquid chromatography (HPLC), or ion chromatography (IC), or the like, depending on the type of the polymerization inhibitor.

[0088] The alkali metal and halogen sometimes contained in the AmSS composition of the present application are impurities derived from the raw materials, and it is desirable to minimize them when used in water-based paints. In general, it is preferable that the content of the alkali metal in the composition be 0.50% by weight or less and the content of the halogen be 1.00% by weight or less. When used in electronic materials, it is more preferable that the content of the alkali metal in the composition be 0.50% by weight or less and the content of the halogen be 0.10% by weight or less. In addition, in the case where the AmSS composition is dissolved in a polar organic solvent to produce a polymer, the more the alkali metal such as sodium, the more the polymer is likely to precipitate during polymerization, and thus it is desirable to minimize it. These metal components can be quantified using high-frequency inductively coupled plasma analysis (ICP-AES) or the like. The impurities such as halogen can be quantified using ion chromatography (IC), the Volhard method, or the like.

[0089] The polymer sometimes contained in the AmSS composition of the present application is an impurity derived from the raw materials or generated during production or storage. In the case where the AmSS is used in the production of an acrylic emulsion, the more the polymer content in the AmSS composition, the more the colloidal stability and the properties of the emulsion coating film decrease, and thus it is desirable to minimize it. It is preferable that the content of the polymer be 0.20% by weight or less and further preferable that it be 0.10% by weight or less.

[0090] Further, when a solid compound such as AmSS is actually used on an industrial scale, AmSS is often dissolved in water or an organic solvent, filtered, and used, but the filterability is drastically deteriorated due to the presence of the polymer component, and thus the polymer component is preferably as little as possible. In particular, in the case where AmSS is dissolved in an organic solvent and filtered, not only the polymer component but also inorganic impurities such as sodium components and inorganic ammonium salts deteriorate the filterability, and thus are preferably as little as possible.

[0091] Further, the amount of the electric charge per unit mass of the AmSS composition can be measured using a small-sized electric charge evaluation device (Suzuki Teruo; Journal of the Electrostatic Society, No. 25, Vol. 1, pp. 37-44, 2001), an electrolytic flying type electric charge amount measuring device (DIT Corporation), an E-SPART analyzer (Sato Keishi; Powder, No. 5, pp. 84-88, 2014), or the like.

[0092] Hereinafter, a manufacturing method of the AmSS composition of the present application will be described.

[0093] As described above, the present inventors and the like have successfully found a composition for maintaining long-term storage stability without impairing the polymerizability when using the AmSS composition, and thus have further intensively studied a simple method for manufacturing the AmSS composition. The target process is simply indicated in the following flow. That is, the aspect based on the cation exchange reaction of the styrenesulfonic acid alkali metal salt and the inorganic ammonium salt is the same as in the past.

[0094]

[0095] As described above, AmSS can be simply obtained by the cation exchange reaction of LiSS and the inorganic ammonium salt, and the reason is that the solubility of LiSS in water is about 2 times higher than that of AmSS, and thus AmSS is preferentially crystallized. On the contrary, the manufacturing method of the present application uses NaSS and potassium styrenesulfonate (hereinafter referred to as KSS) having lower solubility in water than AmSS, and it is generally difficult to consider obtaining high-purity AmSS under such conditions. However, the present inventors and the like have conducted studies, and as a result, it has been found that, surprisingly, AmSS is preferentially crystallized under a high substrate concentration condition. That is, it has been found that by filtering only the aqueous slurry solution shown in the above flow, the crystal of AmSS can be obtained.

[0096] Further, AmSS is a strong electrolyte type hydrophilic compound, and thus it is impossible to avoid the attachment of the mother liquor (filtrate), and to be exact, becomes as Figure 1wet crystal (composition) shown in the schematic diagram. Also, the amount of impurities in the AmSS composition depends on the amount of the mother liquor containing a high concentration of inorganic salts adhered. It was clarified that: as long as the amount of the mother liquor adhered is small, the AmSS crystal having excellent deliquoring properties grows in the reaction system, but in order to obtain a high-quality AmSS crystal, a certain degree of high total matrix concentration is required. That is, a high matrix concentration has the same meaning as a high salt concentration in the mother liquor, and therefore even if the deliquoring properties are improved, the concentration of impurities in the AmSS composition does not decrease. The present inventors found a delicate manufacturing condition that can achieve both the storage stability and high purity of AmSS.

[0097] In the manufacturing condition of the present application, the reason why AmSS preferentially crystallizes is not necessarily clear, and is presumed as follows.

[0098] First, water having a high dielectric constant, which is not an organic solvent, is used as the reaction solvent, and an ammonium cation in an amount of 1.50 equivalents or more relative to NaSS (sodium styrenesulfonate) and KSS (potassium styrenesulfonate) is added, and both have a high degree of ion dissociation, and therefore at least it can be said that the conditions are easy for cation exchange to proceed.

[0099] Second, the difference in the size of the cation is considered. That is, it is known that generally the size of a lithium cation is smaller than that of a sodium cation, and the size of a sodium cation is smaller than that of an ammonium cation, and the smaller the size of the cation, the more easily it hydrates. For example, in fact, when LiSS, NaSS, and AmSS are crystallized from an aqueous solution, LiSS easily forms extremely fine needle-shaped crystals, and therefore has poor deliquoring properties, and the amount of adhered water is as much as 20% by weight or more. On the other hand, NaSS forms large circular plate-shaped crystals, and AmSS easily forms large quadrangular plate-shaped crystals, and therefore has better deliquoring properties than LiSS, and the amount of adhered water is at least less than 20% by weight, and depending on the crystallization conditions, it can be as little as several percent by weight. In particular, it was clarified that AmSS easily forms large crystals having a thickness. This fact is considered to be related to the reason why a high-purity AmSS composition can be obtained under the conditions of the present application.

[0100] Hereinafter, the manufacturing method will be described more specifically. First, water, an alkali metal styrenesulfonate, an inorganic ammonium salt, and a polymerization inhibitor are charged into a reactor in a specific composition, and the raw materials are dissolved or partially dissolved while stirring at a specific temperature for a specific time. Then, while cooling to a predetermined temperature at a specific rate, crystals of AmSS are precipitated and grown. Next, by filtering out the precipitated AmSS crystals, the AmSS composition of the present application can be obtained.

[0101] As the alkali metal styrenesulfonate used, a sodium salt or a potassium salt can be used. In addition, a calcium styrenesulfonate or the like, which is an alkaline earth metal styrenesulfonate, can also be used, but a sodium salt, which is mass-producible, is more preferable.

[0102] As the inorganic ammonium salt, there can be mentioned: ammonium chloride, ammonium bromide, ammonium sulfate, ammonium nitrate, ammonium phosphate, ammonium dihydrogen phosphate, diammonium hydrogen phosphate, ammonium acetate, etc., and, from the viewpoint of economy, such as price, ammonium chloride, ammonium sulfate, ammonium nitrate, ammonium phosphate, ammonium dihydrogen phosphate, and diammonium hydrogen phosphate are more preferable. Further, from the viewpoint of solubility of the alkali metal salt produced as a byproduct by cation exchange, ammonium chloride, ammonium sulfate, and ammonium nitrate are more preferable. Further, from the viewpoint of the residual halogen, ammonium sulfate and ammonium nitrate are more preferable. However, even when ammonium chloride is used to produce AmSS, a high-purity AmSS composition having a small amount of impurities, such as halogen, can be produced by purification by the method described later.

[0103] The polymerization inhibitor is as described above.

[0104] First, the loading composition in the reaction will be described.

[0105] The loading ratio of the ammonium cation to the alkali metal salt of styrenesulfonic acid is preferably 1.50 equivalents to 3.00 equivalents. When the equivalent ratio is less than 1.50 equivalents, the cation exchange rate is low, and the salt concentration in the system decreases, and sometimes it is difficult to produce crystals of high-quality AmSS having good desalting properties. On the other hand, even when the equivalent ratio exceeds 3.00 equivalents, no improvement in desalting properties is found, and instead the inorganic salt concentration in the mother liquor increases, and thus sometimes the purity of the AmSS composition decreases. From the viewpoint of the balance between the inorganic salt concentration in the mother liquor and the desalting properties, 2.00 equivalents to 2.50 equivalents is more preferable.

[0106] Further, the total solid content in the reaction system is preferably 25.00% by weight to 50.00% by weight. When the total solid content is less than 25.00% by weight, not only the yield decreases, but also the desalting properties decrease, and on the other hand, when the total solid content exceeds 50.00% by weight, the inorganic salt concentration in the mother liquor increases, and sometimes the purity of the AmSS composition decreases. From the viewpoint of the balance between the inorganic salt concentration in the mother liquor and the desalting properties, 25.00% by weight to 45.00% by weight is preferable, 30.00% by weight to 45.00% by weight is more preferable, and 35.00% by weight to 45.00% by weight is further preferable.

[0107] Here, the total solid content means the total of the raw materials present in the reaction system which are solid at ordinary temperature, impurities contained in the raw materials which are solid at ordinary temperature, and byproducts which are solid at ordinary temperature.

[0108] The reaction temperature is preferably 30°C to 80°C. In the above loading composition, when the reaction temperature is less than 30°C, sometimes the cation exchange rate is insufficient, and when the reaction temperature exceeds 80°C, the cation exchange rate increases, but sometimes a polymer is easily produced, and thus 30°C to 60°C is more preferable, and 40°C to 60°C is further preferable.

[0109] The reaction time is 10 minutes to 20 hours, which can be adjusted depending on the concentration of the substrate and the reaction temperature, and is preferably 30 minutes to 20 hours, more preferably 10 minutes to 10 hours, and particularly preferably 30 minutes to 10 hours, in order to prevent spontaneous polymerization during the reaction.

[0110] The cooling and filtration temperature is 5°C to 30°C, and after the prescribed cooling temperature is reached, aging is further performed for 0.5 hours to 5 hours. If the cooling temperature is less than 5°C, the impurities such as inorganic salts and moisture of the AmSS composition sometimes increase, and if the cooling temperature exceeds 30°C, the yield sometimes greatly decreases, and thus more preferably 5°C to 25°C, and further preferably 5°C to 20°C.

[0111] The cooling rate can be adjusted depending on the heating temperature and the total solid content, and is preferably 3°C per hour to 40°C per hour. If the cooling rate is too fast, the crystal size sometimes becomes small, and the liquid-removing property decreases. As a result, the moisture and inorganic salts of the AmSS composition sometimes increase. On the other hand, in the case where the cooling rate is extremely slow, the crystal is sometimes broken, and the liquid-removing property decreases, and thus more preferably 5°C per hour to 30°C per hour.

[0112] In order to increase the crystal size of the AmSS and improve the liquid-removing property, more preferably so-called temperature swing crystallization, that is, after cooling to a prescribed temperature to cause the crystal to precipitate, heating to a temperature at which all the crystals do not dissolve, and cooling again. In addition, when the raw materials are charged into the reactor, they can be charged in the form of a powder, or in the form of a saturated aqueous solution of each raw material.

[0113] In addition, as the charging method, either one-shot charging or sequential charging can be used. When the aqueous solution or slurry of the styrenesulfonic acid alkali metal salt is added dropwise to the aqueous solution or saturated aqueous solution of the inorganic ammonium salt, the inclusion of the inorganic salt in the precipitated AmSS crystal is small, and thus a higher-quality AmSS composition is obtained. In addition, the powder or slurry of the styrenesulfonic acid alkali metal salt can also be added to the aqueous solution of the inorganic ammonium salt, but this is disadvantageous in terms of the scattering of the powder and the settling property of the slurry. The atmosphere in the reaction system can be either an inert atmosphere or an air atmosphere, and more preferably an air atmosphere from the viewpoint of suppressing spontaneous polymerization during the reaction.

[0114] In addition, in order to enlarge the crystal size of the AmSS and improve the liquid-removing property, the AmSS can be added as a seed crystal during the cooling from the start of the reaction. The amount of the seed crystal to be added is preferably 1.0 mol% to 20.0 mol% relative to the styrenesulfonic acid unit in the system, and more preferably 1.0 mol% to 10.0 mol% in terms of productivity and thermal history.

[0115] The molar ratio of the ammonium cation to the styrenesulfonic acid alkali metal salt in the production method of the present application is varied by the addition of the AmSS seed crystal, and the ammonium cation herein is defined as the ammonium cation derived from the inorganic ammonium salt charged as a raw material, and does not include the ammonium cation derived from the seed crystal.

[0116] To improve the yield of the resulting AmSS, a water-soluble organic solvent as a poor solvent can be added to the reaction system. For example, alcohols such as methanol, ethanol, 2-propanol, ketones such as acetone, nitriles such as acetonitrile, ethers such as tetrahydrofuran, and the like can be exemplified. From the viewpoint of the increase in inorganic impurities in the AmSS composition, environmental load, and explosion-proof countermeasures, as an industrial method, the solvent of water alone is preferred.

[0117] The filtration of the slurry can be performed by centrifugal filtration, pressure filtration, reduced pressure filtration, filter press, and the like, and centrifugal filtration, which has a large treatment capacity and can be processed in a short time, is more preferred. Furthermore, the resulting AmSS composition can be further purified by recrystallization using water or a mixed solvent of water and the above-described water-soluble organic solvent. At this time, from the viewpoint of productivity, it is preferred that the total solid content in the system be 50.00% by weight to 60.00% by weight, the heating temperature be 40°C to 60°C, and the cooling and filtration temperature be 10°C to 25°C. When recrystallization purification is performed, it is preferred that the above-described polymerization inhibitor be added at 7 mol% or less relative to AmSS.

[0118] Furthermore, the less the moisture, the more excellent the storage stability of the AmSS composition, and thus the water content of the AmSS composition can be reduced by washing the AmSS composition with the above-described water-soluble organic solvent. Furthermore, the AmSS composition can be dried using a tray vacuum dryer, a conical agitator-type dryer (Nauter mixer), a vacuum rotary dryer (conical dryer), a rotary kiln dryer, a spray dryer, a folder dryer, a double-layered cylindrical dryer filter, a vacuum vibration dryer, and the like. However, depending on the drying conditions such as the heating temperature, ammonia is sometimes volatilized and the degree of ammonia neutralization of the styrenesulfonic acid is reduced, and the storage stability of the AmSS composition is rather reduced, and thus it is good to maintain the degree of ammonia neutralization at 100% as much as possible.

[0119] As a result of detailed investigations by the present inventors, it was found that the commercially available NaSS is stabilized as a hemihydrate crystal, and the AmSS composition of the present invention is stabilized as an anhydrous salt crystal. That is, the moisture of the commercially available NaSS includes crystal water and attached water, and in order to remove them, a certain degree of high temperature and degree of reduced pressure are required, and the moisture of the AmSS composition is attached water, and thus even a lower temperature and degree of reduced pressure can remove them. For example, drying can be performed with a stream of dry air or inert gas at ordinary temperature. The drying temperature is preferably 20 to 70°C, and more preferably 20 to 40°C, taking into account the volatilization of the polymerization inhibitor and polymerization of the AmSS.

[0120] The AmSS composition of the present invention is soluble in water, and thus can be used for the production of an aqueous polymer emulsion, hollow polymer particles, an aqueous ammonium polystyrene sulfonate solution, and the like, and in addition, is soluble in a polar organic solvent, and thus is extremely useful for the production of a polymer electrolyte membrane (for example, U.S. Patent No. 6221248), surface modification of an organic material using graft polymerization (for example, Aikichi Saito, High Molecular Adsorbent Revolution Using Graft Polymerization, pp. 8-10, Maruzen Publishing, published in Heisei 26; NHV Corporation homepage https: / / www.nhv.jp / blog / post723 / ).

[0121] The powder X-ray diffraction (PXRD) pattern can be measured by a general procedure. As described above, the AmSS composition of the present invention is presumed to be stabilized as an anhydrous salt crystal, and the PXRD pattern is also presumed to be due to this.

[0122] The AmSS composition of the present invention has diffraction peaks at least at diffraction angles 2Θ of 8.1 ± 0.2°, 15.2 ± 0.2°, 15.4 ± 0.2°, 18.4 ± 0.2°, 20.1 ± 0.2°, 20.6 ± 0.2°, 20.8 ± 0.2°, 24.2 ± 0.2°, 25.8 ± 0.2°, 27.5 ± 0.2°, 30.5 ± 0.2°, 32.5 ± 0.2°, 37.5 ± 0.2°, 43.0 ± 0.2°, and 49.6° ± 0.2°, and in particular, strong diffraction peaks at diffraction angles 2Θ of 8.1 ± 0.2°, 15.2 ± 0.2°, 18.4 ± 0.2°, 20.6 ± 0.2°, 24.2 ± 0.2°, 32.5 ± 0.2°, and 43.0 ± 0.2°. This is a PXRD pattern that is clearly different from sodium styrene sulfonate stabilized as a hemihydrate crystal. The typical error in the peak position is ± 0.2°, and these slight errors can be caused by sample preparation, the measuring instrument, the operator, and the like. Note that, regarding the value of the diffraction peak, for example, “8.2 ± 0.2°” means that a diffraction peak exists at any position in the range of 8.0° to 8.4° (i.e., 8.0° ≤ 2Θ ≤ 8.4°).

[0123] Examples

[0124] The present application is further concretely explained by the following examples, but the present application is not limited by these examples at all.

[0125] <Use of the agent>

[0126] Sodium styrenesulfonate (NaSS): manufactured by TOSOH FINE CHEM Co., Ltd., purity 88.2%, sodium bromide 2.2% by weight, sodium hydroxide 0.40% by weight, sodium sulfate 0.50% by weight, moisture 7.2% by weight, polymer component 0.01% by weight, nitrous acid component 70 ppm.

[0127] Lithium styrenesulfonate (LiSS): manufactured by TOSOH FINE CHEM Co., Ltd., purity 85.3%, lithium bromide 2.5% by weight, lithium hydroxide 0.45% by weight, lithium sulfate 0.50% by weight, moisture 7.1% by weight, polymer component 0.04% by weight, nitrous acid component 60 ppm.

[0128] Ammonium chloride: manufactured by FUJIFILM Wako Pure Chemical Co., Ltd., special grade reagent.

[0129] Ammonium sulfate: manufactured by FUJIFILM Wako Pure Chemical Co., Ltd., special grade reagent.

[0130] Ammonium nitrate: manufactured by FUJIFILM Wako Pure Chemical Co., Ltd., special grade reagent.

[0131] Diammonium hydrogen phosphate: manufactured by FUJIFILM Wako Pure Chemical Co., Ltd., special grade reagent.

[0132] 4-Methoxyphenol: manufactured by FUJIFILM Wako Pure Chemical Co., Ltd., special grade reagent.

[0133] 2-Methoxyphenol: manufactured by FUJIFILM Wako Pure Chemical Co., Ltd., special grade reagent.

[0134] 4-Ethoxyphenol: manufactured by Tokyo Chemical Industry Co., Ltd., purity > 98%.

[0135] 2, 6-Dimethoxyphenol: manufactured by Tokyo Chemical Industry Co., Ltd., purity > 98%.

[0136] Methylhydroquinone: manufactured by Tokyo Chemical Industry Co., Ltd., purity > 98%.

[0137] 4-tert-Butylcatechol: manufactured by FUJIFILM Wako Pure Chemical Corporation, special grade reagent.

[0138] 4-Hydroxy-2, 2, 6, 6-tetramethylpiperidine-1-oxyl radical: manufactured by Tokyo Chemical Industry Co., Ltd., purity >98%.

[0139] Lithium nitrite: manufactured by Honjo Chemical Corporation, 40% by weight aqueous solution.

[0140] Phenolic antioxidant emulsion (Antage 3LX): Kawaguchi Chemicals Co., Ltd.

[0141] 2, 2'-Azobis (2-methylpropionamidine) dihydrochloride (V-50): manufactured by FUJIFILM Wako Pure Chemical Corporation, primary reagent.

[0142] Dimethyl sulfone: manufactured by FUJIFILM Wako Pure Chemical Corporation, special grade reagent.

[0143] N-Methylpyrrolidone: manufactured by FUJIFILM Wako Pure Chemical Corporation, special grade reagent.

[0144] <Quantification of moisture of AmSS>

[0145] Using an infrared moisture meter, the measurement was performed under the following conditions.

[0146] Apparatus: FD-720 manufactured by Kett Electric Laboratory Co., Ltd.

[0147] Conditions: About 5 g of the sample was taken and subjected to heating at 120°C for 20 minutes.

[0148] <Purity analysis of AmSS by redox titration>

[0149] The active double bond was quantified by the following redox titration method as the AmSS purity (i.e., including the ortho body, the meta body, in addition to the para body).

[0150] (1) Apparatus and device

[0151] 1) Volumetric flask: 50 mm in diameter, 70 mm in depth.

[0152] 2) 500 ml, 1000 ml volumetric flask.

[0153] 3) 500 ml stoppered Erlenmeyer flask.

[0154] 4) Electronic chemical balance.

[0155] (2) Reagent

[0156] 1) Bromine solution: Dissolve potassium bromide (KBr) 22.00 g and potassium bromate (KBrO3) 3.00 g in pure water to make 1000 ml.

[0157] 2) Aqueous sulfuric acid solution (volume ratio of concentrated sulfuric acid / pure water = 1 / 1).

[0158] 3) Aqueous potassium iodide solution (200 g / L).

[0159] 4) 0.1 mol / L aqueous sodium thiosulfate solution.

[0160] 5) Aqueous starch solution: Dissolve 6.00 g of starch in pure water to make 1000 ml.

[0161] (3) Operation

[0162] 1) Weigh 20 g of the sample into a weighing bottle with an accuracy of 0.1 mg.

[0163] 2) Wash with pure water and transfer to a 500-ml volumetric flask to make the liquid volume about 400 ml.

[0164] 3) Add a magnetic stirrer to dissolve the sample.

[0165] 4) Remove the stirrer, align it with the mark using pure water, and mix by shaking to prepare the test solution.

[0166] 5) Add 25 ml of bromine solution to a 500-ml stoppered flask containing 200 ml of pure water.

[0167] 6) After adding 5 ml of the test solution, add 10 ml of aqueous sulfuric acid and seal it for 20 minutes.

[0168] 7) Quickly add 10 ml of aqueous potassium iodide solution and let stand for 10 minutes.

[0169] 8) Titrate with aqueous sodium thiosulfate solution. After the yellow color of the solution fades, add 1 ml of starch solution as an indicator and titrate until the blue color of the iodine starch produced disappears.

[0170] 9) In addition, as a blank test, add 200 ml of pure water to a stoppered flask, add 25 ml of bromine solution, and quickly add 10 ml of aqueous potassium iodide solution and 10 ml of aqueous sulfuric acid, and perform the operation of 8).

[0171] (4) Calculation

[0172] The AmSS content is calculated by the following formula.

[0173] A = 100 x [0.01006 x (a - b) x f] / (S x 5 / 500)

[0174] A: AmSS content (%).

[0175] a: Amount of aqueous sodium thiosulfate solution required for blank test (ml).

[0176] b: Amount of aqueous sodium thiosulfate solution required for this test (ml).

[0177] f: Titer of aqueous sodium thiosulfate solution.

[0178] S: Sample amount (g).

[0179] Elemental Analysis of AmSS

[0180] The carbon content, hydrogen content, and nitrogen content were quantified using an elemental analysis meter.

[0181] Apparatus: PerkinElmer Co., Ltd. 2400 II.

[0182] Quantification of Sulfur Content of AmSS

[0183] The combustion gas of the AmSS composition combusted by the oxygen bottle combustion method was absorbed into a hydrogen peroxide absorption solution to prepare an absorption solution. The concentration of sulfate ions in the absorption was then quantified by ion chromatography (under the measurement conditions described below), and converted to the sulfur content.

[0184] Quantification of Bromide Anion, Chloride Anion, Sulfate Anion, Nitrate Anion, and Nitrite Anion of AmSS

[0185] Quantification was performed using ion chromatography under the following conditions.

[0186] Apparatus: TOSOH Co., Ltd. IC-2010.

[0187] Column: TSKgel (registered trademark) guard column Super IC-AHS (4.6 mm I.D. x 1 cm) + TSKgel (registered trademark) Super IC-Anion HS (4.6 mm I.D. x 10 cm).

[0188] Column temperature: 40°C, injection volume: 30 μl, flow rate: 1.5 ml / min.

[0189] Eluent: Carbonate buffer (7.5 mM-NaHCO3+0.8 mM-Na2CO3).

[0190] Preparation of sample solution: The AmSS composition was dissolved in ultrapure water, diluted 10-fold, and passed through a pretreatment cartridge (TOYOPAK (registered trademark) ODSM) to prepare a measurement sample.

[0191] Calibration curve: Absolute calibration curve method using standard solution.

[0192] <Using proton nuclear magnetic resonance ( 1 Analysis of AmSS by H-NMR>

[0193] The molar ratio of ammonium cations to the AmSS component, water, and styrenesulfonic acid units was analyzed under the following conditions.

[0194] (1) Sample preparation

[0195] A sample for measurement was prepared by dissolving a sample in about 0.7 mL of dimethyl sulfoxide-d6 (99.5 wt %) containing about 0.05 wt % of tetramethylsilane as an internal standard substance.

[0196] (2) Measurement equipment / conditions

[0197] Model = Bruker AV-400M.

[0198] Cumulative number of times = 16.

[0199] Nuclide = 1H.

[0200] (3) Calculation of the molar ratio of ammonium cation (NH4) / styrene sulfonic acid unit (SS)

[0201] Use the following formula to calculate.

[0202] NH4 / SS=〔n / (nH)〕 / 〔s / (sH)〕

[0203] s: integrated value of the peak derived from vinyl groups in SS (peak position: δ 5.30 ppm, d).

[0204] n: integrated value of the peak derived from NH 4 (peak position: δ7.22 ppm, s, but sometimes split into three due to moisture).

[0205] sH: the number of hydrogen atoms in the peak of s (=1).

[0206] nH: the number of hydrogen atoms in the peak of n (=4).

[0207] Note that the peak positions are when dimethyl sulfoxide-d6 is used as a deuterated solvent, and the chemical shifts fluctuate slightly depending on the amount of impurities.

[0208] (4) Calculation of the molar ratio of water (H2O) / styrene sulfonic acid unit (SS)

[0209] The AmSS component in the AmSS composition was calculated using the following formula.

[0210] H2O / SS = [m / (mH)] / [s / (sH)]

[0211] s: integral value of the peak derived from the vinyl group of SS (peak position: δ 5.30 ppm, d).

[0212] m: integral value of the peak derived from H2O (peak position: δ 3.40 ppm, s).

[0213] sH: number of hydrogen of the peak of s (= 1).

[0214] mH: number of hydrogen of the peak of m (= 2).

[0215] Note that dimethyl sulfoxide-d6 sometimes contains moisture, and therefore the moisture in dimethyl sulfoxide-d6 was quantified in advance, and the integral value was corrected.

[0216] (5) Calculation of AmSS component

[0217] The AmSS component in the AmSS composition was calculated using the following formula.

[0218] AmSS component (wt%) = (B / Mb) x (a / aH) / (b / bH) x Ma / S x 100

[0219] a: integral value of the peak derived from the vinyl group of AmSS (peak position: δ 5.30 ppm, d).

[0220] b: integral value of the peak derived from the internal standard substance dimethyl sulfone (peak position: δ 3.00 ppm, s).

[0221] aH: number of hydrogen of the peak of a (= 1).

[0222] bH: number of hydrogen of the peak of b (= 6).

[0223] Ma: molecular weight of AmSS.

[0224] Mb: molecular weight of the internal standard substance.

[0225] B: amount of internal standard taken (g).

[0226] S: amount of sample taken (g).

[0227] <Analysis of alkali metal component of AmSS>

[0228] The sodium component and the lithium component were quantified using a high-frequency inductively coupled plasma emission spectrometer OPTIMA 8300 (manufactured by PerkinElmer) (hereinafter referred to as ICP-AES). The object sample was wetly decomposed using sulfuric acid and nitric acid, and the decomposed sample was heated and dried. Nitric acid was added to the dried sample, and the sample was heated and dissolved. After the sample was diluted to a predetermined amount, 1 ppm of scandium as an internal standard was added, and the sample was quantified.

[0229] <Analysis of the polymer component and the polymerization inhibitor of AmSS>

[0230] The analysis was performed using gel permeation chromatography (GPC) under the following conditions.

[0231] Apparatus: HLC-8320 (manufactured by TOSOH CORPORATION).

[0232] Column: TSKgel (registered trademark) guard column AW-H / TSKgel (registered trademark) AW-6000 / TSKgel (registered trademark) AW-3000 / TSKgel (registered trademark) AW-2500.

[0233] Eluent: 0.05 M sodium sulfate aqueous solution / acetonitrile = 65 / 35 (volume ratio) solution.

[0234] Sample: A 1 wt% solution of the AmSS composition (as is) was prepared using the above eluent.

[0235] Flow rate / injection amount / column temperature: 0.6 ml / min, injection amount: 10 μl, column temperature: 40°C.

[0236] Detector: UV detector (wavelength 230 nm).

[0237] Calibration curve: A calibration curve was prepared using sodium polystyrene sulfonate (3K, manufactured by KANTO CHEMICAL CO., INC.) and the above eluent. Note that all absorption peaks having an elution time of less than 13.00 minutes were regarded as the polymer component.

[0238] In addition, a calibration curve was prepared for the polymerization inhibitor by the same method.

[0239] <Measurement of the polymerization conversion rate and the molecular weight of AmSS during polymerization>

[0240] Determined by GPC under the same conditions as described above (wherein the sample concentration was 0.1% by weight). Note that the molecular weight was automatically calculated using internal software based on a calibration curve prepared from the peak top molecular weight and elution time of standard polystyrene sulfonic acid sodium salt (Creative Polymer, 3K, 15K, 41K, 300K, 1000K, 2350K, 5000K), and the polymerization conversion was calculated from the peak area of monomer (a) and the peak area of polymer (b) using the following equation.

[0241] Conversion (area %) = 100 x [1 - {a / (a+b)}]

[0242] <Confirmation of long-term storage stability of AmSS>

[0243] The AmSS was sealed in a glass sample bottle, and after aging in an oven at 60°C for a prescribed period of time, the sample was allowed to return to room temperature, and the APHA value and polymer content were determined. The APHA value was determined under the same conditions as described below, and the polymer content was determined using the same GPC as described above (sample concentration: 1% by weight).

[0244] <Analysis of hue of AmSS>

[0245] The APHA value was determined as follows. After turning on the power of a color difference meter (ZE-6000, Nippon Denshoku Industries Co., Ltd.) and allowing it to stabilize for 30 minutes, the measurement method was set to transmission, and the light source / viewing field setting was set to C / 2. After adding water to a square cuvette (cell length: 36 mm) and performing standard calibration, an AmSS aqueous solution prepared at 10% by weight (as-is reference) was moved to the square cuvette and set, and the APHA value was determined.

[0246] <Determination of median particle diameter of AmSS>

[0247] Using a Microtrac particle size analyzer (MT-3300EXII, Nikkiso Co., Ltd.), determination was performed under the following conditions. About 0.5 g of the AmSS composition was put into 200 ml of hexane to prepare a sample liquid, laser light was irradiated to the sample liquid, and the particle size was determined from the diffraction (scattering). Note that in preparing the sample liquid, no ultrasonic treatment or the like was performed, and the determination was performed under the following conditions: particle transmission = transmission, particle shape = non-spherical, particle refractive index = 1.81, and solvent refractive index = 1.38. Furthermore, in the case where the moisture content of the AmSS composition exceeded 10% by weight, the dispersibility in hexane was reduced, so the moisture content of the AmSS composition was dried to 10% by weight or less using a rotary evaporator in advance for sample preparation.

[0248] <Determination of the amount of electric charge (air transport method) of AmSS>

[0249] The sample was put into the powder supply part of the charging tube, and after 10 minutes, the sample was transported using air with a flow rate of 130 L / min, and the amount of charge on the charging tube side was calculated from the voltage value obtained from the Faraday cage and the current value obtained from the charging tube.

[0250] Electrometer: Model 6514 (manufactured by KEITHLEY).

[0251] Charging tube: SUS 24.6φ x 500 mm.

[0252] Measurement temperature: 25 to 26°C (humidity 20 to 30%).

[0253] Sample amount: about 0.50 g.

[0254] X-ray Diffraction (XRD) Measurement of AmSS

[0255] The composition obtained in the example was pulverized using a mortar, and XRD was measured by the following method. All sample preparation and measurement were performed under an air atmosphere, and the measurement data were analyzed using HighScore Plus XRD analysis software.

[0256] Apparatus: X-ray analysis device Aeris manufactured by Malvern Panalytical.

[0257] X-ray source: Cu Kα1 Cu Kα2 Kα2 / Kα1 ratio = 0.5.

[0258] Output: 40 kV and 7.5 mA.

[0259] Geometry: Bragg-Brentano method, sample horizontal type (θ-θ).

[0260] Step size: 0.02° 2θ.

[0261] Scan step time: 148.9 s.

[0262] Scan range: continuous scan from 2θ = 4° (start) to 2θ = 80° (end).

[0263] Production of AmSS using NaSS and ammonium sulfate (1)

[0264] A 2L cylindrical glass separable flask equipped with a reflux condenser was charged with 290.00g of NaSS powder, 3.17g of 4-methoxyphenol, 185.04g of ammonium sulfate, and 719.30g of ion-exchanged water. A cation exchange reaction was performed while stirring at an internal temperature of 45°C for 60 minutes using a stirrer. The mixture was then cooled to 25°C over 4 hours and aged for 2 hours, yielding a white slurry.

[0265] Next, the slurry was centrifuged (600G×15 minutes, room temperature) to obtain plate-shaped wet crystals ( Figure 3 The slurry had good deliquescence properties, and the moisture content of the wet crystals determined using an infrared moisture analyzer was 8.00 wt%.

[0266] The sodium content of the wet crystals determined by ICP was 0.27 wt% (the theoretical Na content in pure NaSS is 11.1 wt%), the nitrogen content determined by elemental analysis was 6.7 wt% (the theoretical nitrogen content in pure AmSS is 7.0 wt%), and the 1 The molar ratio of ammonium cation to styrenesulfonic acid unit determined by H-NMR was 1.00 ( Figure 2 ) (the theoretical molar ratio of ammonium cations to styrenesulfonic acid units in pure AmSS is 1.00), and therefore the wet crystals were judged to be the target AmSS composition.

[0267] The AmSS content, i.e., the purity, of the AmSS composition determined by redox titration was 90.6% by weight (the yield based on the molar basis of the raw material NaSS was 74%). The reaction formula and results are summarized in Table 1.

[0268] It was found that the alkali metal component, halogen component, and polymer component in the AmSS composition were smaller than those in Comparative Examples 1 to 2, 4 to 6, 7, and 11 (Tables 5 and 7) described later, and were of high purity.

[0269] Furthermore, the median particle size of the AmSS was 420 μm, which was much larger than 11 μm shown in Comparative Example 11 (Table 7). Therefore, it can be expected that the dust generation property is lower than that of Comparative Example 11.

[0270] Furthermore, it was found that the AmSS composition had a low water content and contained 460 ppm of 4-methoxyphenol, resulting in superior storage stability compared to Comparative Example 3 (Table 5). Furthermore, it was found that the AmSS composition contained low amounts of lithium and nitrous acid, resulting in less coloration compared to Comparative Examples 8 to 10 (Table 6).

[0271] Further, the charged electric quantity per unit mass of the AmSS composition was 0.083 μC / g, which was slightly lower than 0.110 μC / g of the Comparative Example 11 (Table 7) having less moisture.

[0272] [Table 1]

[0273]

[0274] * AmSS composition (as is) 10 wt% aqueous solution

[0275] Example 2: Production of AmSS using NaSS and ammonium sulfate (2)

[0276] A cylindrical 2 L separable glass flask equipped with a reflux condenser was charged with NaSS powder 290.00 g, 4-methoxyphenol 7.00 g, ammonium sulfate 230.00 g, and ion exchange water 750.00 g, and a cation exchange reaction was performed using a stirrer while stirring at an internal temperature of 45°C for 60 minutes. Then, the temperature was cooled to 35°C over 30 minutes, and after maintaining the temperature for 10 minutes, the temperature was again increased to an internal temperature of 45°C. The heating was stopped when the internal temperature reached 45°C, and the temperature was cooled to 25°C over 4 hours, and the temperature was maintained for 2 hours for maturation, and a white slurry was obtained.

[0277] Next, the slurry was subjected to centrifugal filtration under the same conditions as in Example 1, and a wet crystal in the form of a plate was obtained in an amount of 195.36 g. The slurry was well dewatered, and the moisture content was 7.86 wt% as measured using an infrared moisture meter.

[0278] The sodium content of the wet crystal was 0.27 wt% as measured using ICP (the theoretical Na content in pure NaSS was 11.1 wt%), the nitrogen content was 6.7 wt% as measured by elemental analysis (the theoretical nitrogen content in pure AmSS was 7.0 wt%), and the ammonium cation content was 1.01 as measured by H-NMR (the theoretical molar ratio of the ammonium cation to the styrene sulfonic acid unit in pure AmSS was 1.00), and thus the wet crystal was determined to be the AmSS composition as the target product. 1 The molar ratio of the ammonium cation to the styrene sulfonic acid unit in the AmSS composition was 1.01 as measured by H-NMR (the theoretical molar ratio of the ammonium cation to the styrene sulfonic acid unit in pure AmSS was 1.00), and thus the wet crystal was determined to be the AmSS composition as the target product.

[0279] The AmSS content, i.e., the purity, of the AmSS composition was 90.8 wt% as measured by redox titration (the yield on a NaSS raw material molar basis was 71%). The reaction formula and the results are summarized in Table 1. It was confirmed that the alkali metal content, the halogen content, and the polymer content in the AmSS composition were less than those in Comparative Examples 1 to 2, Comparative Examples 4 to 6, Comparative Example 7, and Comparative Example 11 (Tables 5 and 7), and the purity was high.

[0280] Further, the median particle diameter of the AmSS was 349 μm, which was much larger than 11 μm shown in Comparative Example 11 (Table 7), and thus it was expected that the dust raising property was lower than that of Comparative Example 11.

[0281] Further, it was confirmed that the AmSS composition contained 356 ppm of 4-methoxyphenol, and thus the storage stability was excellent compared to Comparative Example 3 (Table 5). Further, it was confirmed that the lithium component and the nitrous acid component were small, and thus the coloring was less likely to occur compared to Comparative Examples 8 to 10 (Table 6).

[0282] Further, the charged electric quantity per unit mass of the AmSS composition was 0.082 μC / g, which was slightly lower than that of Comparative Example 11 (Table 7) which was low in moisture content.

[0283] <Example 3> Production of AmSS using NaSS and ammonium sulfate (3)

[0284] Synthesis of AmSS

[0285] In Example 1, the composition and the temperature conditions were changed to those shown in Table 1, and a wet crystal in the shape of a plate which was presumed to be an AmSS was obtained by the same operation as in Example 1.

[0286] From the analysis results shown in Table 1, it was judged that the above wet crystal was an AmSS composition. It was confirmed that the alkali metal component, the halogen component, and the polymer component in the AmSS composition were small compared to Comparative Examples 1 to 2, Comparative Examples 4 to 6, Comparative Example 7, and Comparative Example 11 (Tables 5 and 7), and thus the purity was high.

[0287] Further, the median particle diameter of the AmSS was 374 μm, which was much larger than 11 μm shown in Comparative Example 11 (Table 7), and thus it was expected that the dust raising property was lower than that of Comparative Example 11.

[0288] Further, it was confirmed that the AmSS composition contained 356 ppm of 4-methoxyphenol, and thus the storage stability was excellent compared to Comparative Example 3 (Table 5). Further, it was confirmed that the lithium component and the nitrous acid component were small, and thus the coloring was less likely to occur compared to Comparative Examples 8 to 10 (Table 6).

[0289] Further, the charged electric quantity per unit mass of the AmSS composition was 0.082 μC / g, which was slightly lower than that of Comparative Example 11 (Table 7) which was low in moisture content.

[0290] Polymerization of AmSS

[0291] It was confirmed that the AmSS composition had radical polymerizability.

[0292] In a 300 ml three-neck flask reactor equipped with a condenser tube, a magnetic induction type stirrer, and a nitrogen introduction tube, 10.00 g of the AmSS wet crystal obtained above, 1.00 g of an aqueous solution of a polymerization initiator (1.85 wt% aqueous solution of V-50), and 80.00 g of ion exchange water were repeatedly subjected to reduced pressure using an aspirator and nitrogen introduction to perform deoxidation. Then, the reactor was immersed in a 60°C bath, and polymerization was initiated while stirring. Samples were taken at regular intervals, and the polymerization conversion rate and molecular weight were measured using GPC. According to the results shown in Table 2, it was confirmed that there was no significant difference in the polymerization rate and molecular weight compared to Example 2, 4, and Comparative Example 3 in which the amount of methoxyphenol was small.

[0293] [Table 2]

[0294]

[0295] Manufacture of AmSS using NaSS and ammonium sulfate (4)

[0296] Synthesis of AmSS

[0297] A cylindrical 2 L separable glass flask equipped with a reflux condenser tube was charged with NaSS powder 290.00 g, 4-methoxyphenol 1.58 g, ammonium sulfate 184.55 g, and ion exchange water 1450.00 g, and a cation exchange reaction was performed using a stirrer while stirring at an internal temperature of 45°C for 30 minutes. Then, it was cooled to an internal temperature of 30°C over 30 minutes, and after slurry was formed, AmSS composition obtained in Example 1 was added as a seed crystal 52.73 g, and stirring was continued for 10 minutes (ammonium cation derived from ammonium sulfate was 2.25 equivalents with respect to the charged amount of NaSS, and the total solid content was 25.46 wt%). Then, it was cooled to 10°C over 3 hours, and aging was performed for 2 hours while maintaining this state, and a white slurry liquid was obtained. Then, the slurry liquid was centrifugally filtered in the same manner as in Example 1, and thus a plate-shaped wet crystal 239.12 g was obtained.

[0298] According to the analysis results shown in Table 1, the wet crystal above was determined to be an AmSS composition. It was confirmed that 156 ppm of 4-methoxyphenol was contained in the AmSS composition, and thus the storage stability was excellent compared to Comparative Example 3 (Table 5). Furthermore, it was confirmed that the lithium component and the nitrous acid component were small, and thus coloring was less likely to occur compared to Comparative Examples 8 to 10 (Table 6).

[0299] In addition, the median particle diameter of the AmSS was 356 μm, which was much larger than 11 μm shown in Comparative Example 11 (Table 7), and thus it was expected that the dust raising property would be lower than that of Comparative Example 11. Furthermore, the charge capacity per unit mass of the AmSS composition was 0.077 μC / g, which was slightly lower than that of Comparative Example 11 in which the water content was small (Table 7).

[0300] Polymerization of AmSS composition

[0301] The radical polymerizability of the AmSS composition was confirmed under the same conditions as in Example 3. According to the results shown in Table 2, it was clear that there was no significant difference in the polymerization rate and molecular weight compared with Example 2, 3, and Comparative Example 3 in which the amount of 4-methoxyphenol was small.

[0302] <Example 5> Production of AmSS using NaSS and ammonium sulfate (5)

[0303] Into a cylindrical 2L separable flask equipped with a reflux condenser, 423.79 g of NaSS powder, 4.65 g of 4-methoxyphenol, 269.90 g of ammonium sulfate, and 1048.89 g of ion exchange water were charged, and a cation exchange reaction was performed using a stirrer while stirring at an internal temperature of 45°C for 60 minutes. Then, it was cooled to 15°C over 5 hours, and kept in this state for 2 hours for maturation, and a white slurry liquid was obtained.

[0304] Next, the slurry liquid was subjected to centrifugal filtration (600 G x 20 minutes, room temperature), and thereby a plate-shaped wet crystal 320.66 g was obtained. The slurry had good dewatering properties, and the moisture content of the wet crystal was 5.10% by weight as measured by an infrared moisture meter.

[0305] The wet crystal was dried using a rotary evaporator at 40°C for 30 minutes (pressure 660 Pa), and a dried crystal 293.35 g was obtained.

[0306] The sodium content of the AmSS was 0.21% by weight as measured by ICP, the nitrogen content was 6.8% by weight as measured by elemental analysis, and the ammonium cation content was 1.00 mole per mole of styrene sulfonic acid unit as measured by H-NMR, and thus it was judged that the dried crystal was the AmSS composition as the target product. 1 H-NMR, and thus it was judged that the dried crystal was the AmSS composition as the target product.

[0307] The AmSS content, i.e., the purity, of the dried crystal was 98.4% by weight (yield of 82% based on the raw material NaSS) as measured by redox titration. The reaction formula and results are summarized in Table 3.

[0308] Further, the wet crystal was good in drying property, and the moisture content was reduced to 0.27% by weight after drying by a rotary evaporator. The drying property was not changed even when the wet crystal was stored in a closed container at normal temperature for 6 months. On the other hand, NaSS used as a raw material was dried under the same conditions, and the moisture content was 3.69% by weight. That is, it was found that the moisture content of the wet crystal of the above AmSS was attached water, and the drying property was completely different from that of the crystal water contained in the raw material NaSS. That is, it is considered that the AmSS composition of the present application is stabilized as an anhydrous salt crystal.

[0309] It was confirmed that the alkali metal component, the halogen component, and the polymer component in the AmSS composition were less than those of Comparative Examples 1 to 2, Comparative Examples 4 to 6, Comparative Example 7, and Comparative Example 11 (Tables 5 and 7) to be described later, and were of high purity.

[0310] Further, the median particle diameter of the AmSS was 367 μm, which was much larger than 11 μm shown in Comparative Example 11 (Table 7), and thus it was expected that the dust raising property was lower than that of Comparative Example 11.

[0311] Further, it was confirmed that the moisture content of the AmSS composition was small, and that 4-methoxyphenol was contained at 289 ppm, and thus the storage stability was excellent compared to Comparative Example 3 (Table 4). Further, it was confirmed that the lithium component and the nitrous acid component were small, and thus the coloring was not likely to occur compared to Comparative Examples 8 to 10 (Table 6). Note that the polymer component after the 60°C storage stability test was extended to at least 210 days was 0.03% by weight, and the stability was extremely high.

[0312] Further, the electric charge amount per unit mass of the AmSS composition was 0.093 μC / g, which was higher than those of Examples 1 to 4, but was slightly lower than that of Comparative Example 11 (Table 7) having a small particle diameter.

[0313] Further, the PXRD patterns of the wet AmSS, the dried AmSS, and NaSS used as a raw material obtained in this example were compared, and as a result Figures 7-12 ), the diffraction patterns of the AmSS and NaSS were significantly different. It is considered that the reason is largely due to the difference between NaSS stabilized as a hemihydrate salt crystal and AmSS stabilized as an anhydrous salt crystal.

[0314] [Table 3]

[0315]

[0316] * AmSS composition (as is) 10% by weight aqueous solution

[0317] <Example 6> Purification of AmSS composition

[0318] A 0.5 L cylindrical separable glass flask equipped with a reflux condenser was charged with the AmSS composition 132.90 g obtained in Example 1, 4-methoxyphenol 0.74 g, and ion exchange water 85.00 g, and stirred for 60 minutes at an internal temperature of 55°C using a stirrer. Then, after cooling to an internal temperature of 35°C over 60 minutes, the temperature was again raised to 45°C. The heating was stopped when the internal temperature reached 45°C, and the temperature was allowed to cool to 25°C over 4 hours. After maintaining this state for 2 hours to allow maturation, the slurry liquid was centrifugally filtered in the same manner as in Example 1, thereby obtaining an AmSS composition 95.43 g.

[0319] As shown in Table 4, it was confirmed that the purity was further increased as compared with Examples 1 to 4, and the storage stability was excellent as compared with Comparative Example 3 (Table 5). Furthermore, it was confirmed that the lithium component and the nitrous acid component were small, and thus the composition was not easily colored as compared with Comparative Examples 8 to 10 (Table 6).

[0320] Furthermore, it was confirmed that the median particle diameter was 278 μm, which was much larger than 11 μm shown in Comparative Example 11 (Table 7), and thus the dusting property was low.

[0321] Furthermore, the above AmSS composition was dried for 30 minutes at 40°C using a rotary evaporator (pressure 665 Pa), and as a result, the drying property was good, the moisture content was reduced to 0.31 wt%, and the purity was increased to 99.3%.

[0322] The dried AmSS composition was taken to a glass dish, and after being left in a constant temperature and humidity chamber at 30°C and a relative humidity of 75% for 24 hours, the moisture content was 0.52 wt%. On the other hand, the same operation was performed using NaSS having a moisture content of 0.15 wt% prepared by vacuum drying at 60°C for 12 hours, and as a result, the moisture content was increased to 4.95 wt%. Thus, it was considered that the NaSS was stabilized as a hemihydrate crystal, and in contrast, the AmSS composition of the present application was stabilized as an anhydrous salt crystal.

[0323] The above dried AmSS composition was crushed for 10 seconds at room temperature at 4000 rpm using a small bench-top dynamic mill (Showa Chemical Machinery Works Co., Ltd., P-02S), and as a result, the median particle diameter was reduced to 56 μm. In the same manner as above, the crushed product was taken to a glass dish, and left in a constant temperature and humidity chamber at 30°C and a relative humidity of 75% for 24 hours. As a result, although the median particle diameter was greatly reduced, the moisture content was only increased to 0.58 wt%. The reason for this is that the AmSS composition was stabilized as an anhydrous salt crystal.

[0324] [Table 4]

[0325]

[0326] *AmSS composition (as is) 10 wt% aqueous solution

[0327] <Comparative Example 1> Production of AmSS using NaSS and ammonium sulfate (6)

[0328] In Example 4, the loading composition and temperature conditions were changed to those shown in Table 5, and production of AmSS was attempted. From the analysis results of the sodium and nitrogen contents in the obtained wet crystals (Table 5), it was judged that the wet crystals were an AmSS composition, but the dewatering property of the slurry was poor, and therefore the moisture content of the composition was as much as 18.90 wt%, and the purity was as low as 77.2%, which was significantly lower than in Examples 1 to 4.

[0329] The storage stability was significantly poorer than in Examples 1 to 4, despite the presence of 169 ppm of 4-methoxyphenol. The reason for this is that the moisture content was high, and it is thought that the moisture content increased because the total solid content during the reaction was too low.

[0330] <Comparative Example 2> Production of AmSS using NaSS and ammonium sulfate (7)

[0331] In Example 4, the loading composition and temperature conditions were changed to those shown in Table 5, and production of AmSS was attempted. From the analysis results of the sodium and nitrogen contents in the obtained wet crystals (Table 5), it was judged that the wet crystals were an AmSS composition, but the dewatering property of the slurry was poor, and therefore the moisture content of the composition was as much as 21.00 wt%, and the purity was as low as 75.2%, which was significantly lower than in Examples 1 to 4.

[0332] The storage stability was significantly poorer than in Examples 1 to 4, despite the presence of 174 ppm of 4-methoxyphenol. The reason for this is that the moisture content was high, and it is thought that the moisture content increased because the amount of added ammonium sulfate relative to NaSS during the reaction was too high.

[0333] <Comparative Example 3> Production of AmSS using NaSS and ammonium chloride (1)

[0334] In Example 4, the inorganic ammonium salt species, the loading composition, and the temperature conditions were changed to those shown in Table 5, and production of AmSS was attempted. From the analysis results of the sodium and nitrogen contents in the obtained wet crystals (Table 5), it was judged that the wet crystals were an AmSS composition. The dewatering property of the slurry was good, the moisture content of the AmSS composition was as little as 7.54 wt%, and although the halogen content was slightly high, the purity was 90.1%, which was equivalent to that in Examples 1 to 4.

[0335] However, the storage stability was significantly poorer than in Examples 1 to 4. It is thought that the reason for this is that, although the moisture content was low, the 4-methoxyphenol content was as little as 16 ppm, which was too low.

[0336] <Comparative Example 4> Production of AmSS using NaSS and ammonium chloride (2)

[0337] In Example 1, the inorganic ammonium salt species, the loading composition, and the temperature conditions were changed to those shown in Table 5, and the production of AmSS was attempted. From the results of analysis of the sodium and nitrogen contents in the obtained wet crystal (Table 5), it was determined that the wet crystal was an AmSS composition, but the dewatering property of the slurry was poor, and therefore the moisture content of the composition was 17.30 wt%, the halogen content was as high as 2.01 wt%, and the purity was as low as 80.1%, which was significantly lower than in Examples 1 to 4. It is believed that the reason for this is that the reaction temperature was too low.

[0338] In addition, although the 4-methoxyphenol content in the above AmSS composition was 78 ppm, the storage stability was also significantly poorer than in Examples 1 to 4. It is believed that the reason for this is that the moisture content was high.

[0339] <Comparative Example 5> Production of AmSS using NaSS and ammonium chloride (3)

[0340] In Example 1, the inorganic ammonium salt species, the loading composition, and the temperature conditions were changed to those shown in Table 5, and the production of AmSS was attempted. From the results of analysis of the sodium and nitrogen contents in the obtained wet crystal (Table 5), it was determined that the sodium content was as high as 6.47 wt%, which was very high, and the cation exchange rate was less than 50%. It is believed that the reason for this is that the molar ratio of the added ammonium cation to NaSS was 0.96 equivalents, which was too low.

[0341] <Comparative Example 6> Production of AmSS using NaSS and ammonium sulfate (8)

[0342] Synthesis of AmSS

[0343] In Example 4, the loading composition and the temperature conditions were changed to those shown in Table 5, and the production of AmSS was attempted. From the results of analysis of the sodium and nitrogen contents in the obtained wet crystal (Table 5), it was determined that the wet crystal was an AmSS composition. The dewatering property of the slurry was good, the moisture content of the AmSS composition was as low as 7.75 wt%, the halogen content was as low as 0.02 wt%, and the purity was as high as 90.4%, which was equivalent to that in Example 4.

[0344] However, the amount of added 4-methoxyphenol during the reaction was increased, and therefore the 4-methoxyphenol content in the above AmSS composition was increased to 2204 ppm. Therefore, the spontaneous polymerization property at the time of storage at 60°C was suppressed as in Examples 1 to 3, but the APHA value increased, and, as shown in Table 2 and below, an adverse effect on the polymerization property at the time of polymer production was observed.

[0345] Polymerization of AmSS

[0346] The polymerizability of the above AmSS composition was confirmed under the same conditions as in Example 3. As a result, it was confirmed that the polymerization speed was significantly slower and the molecular weight was lower than in Comparative Example 3 in which the amount of 4-methoxyphenol was small (Table 2).

[0347] <Comparative Example 7> Production of AmSS using NaSS and ammonium sulfate (9)

[0348] In Example 3, the reaction temperature was changed from 60°C to 85°C, and the production of AmSS was attempted. According to the analysis results of the sodium content and nitrogen content of the obtained wet crystal, it was judged that the wet crystal was an AmSS composition (Table 5). However, the dewatering property of the slurry was poor, the moisture of the AmSS composition was as high as 13.70% by weight, and thus the purity was as low as 84.3% by weight, which was significantly worse than in Examples 1 to 4. It is considered that the reason for this is that the reaction temperature was too high, and thus a high-quality crystal was not produced, and the reason is that the amount of polymer produced increased, and the dewatering property decreased.

[0349] Furthermore, although the 4-methoxyphenol content in the above AmSS composition was 394 ppm, the moisture was high, and thus the storage stability was significantly worse than in Examples 1 to 4.

[0350] [Table 5]

[0351]

[0352] * AmSS composition (as is) 10% by weight aqueous solution

[0353] <Comparative Example 8> Production of AmSS using LiSS and ammonium chloride (1)

[0354] A cylindrical 2L separable flask equipped with a reflux condenser was charged with LiSS powder 541.54 g, lithium nitrite (40% by weight aqueous solution) 1.20 g, ammonium chloride 150.18 g, and ion exchange water 1135.09 g, and a cation exchange reaction was performed using a stirrer while stirring at an internal temperature of 35°C for 60 minutes. Then, it was cooled to 5°C over 5 hours, and the internal temperature was cooled to 5°C. This state was maintained for 2 hours of maturation, and a white slurry liquid was obtained. Subsequently, the above slurry liquid was subjected to centrifugal filtration under the same conditions as in Example 1, and thus a wet crystal 423.65 g in the shape of a rhombic plate was obtained. The dewatering property of the slurry was good, and the moisture content was 9.62% by weight as measured using an infrared moisture meter.

[0355] The lithium content of the above wet crystal was 0.13% by weight (the theoretical lithium content in pure LiSS was 3.65% by weight) and the sodium content was 5 ppm by ICP. The nitrogen content of the AmSS composition was 6.3% by weight (the theoretical nitrogen content in pure AmSS was 7.0% by weight) by elemental analysis, and the AmSS content, i.e., the purity, of the above AmSS composition was 89.2% by redox titration (the yield based on the raw material LiSS was 77%). 1 The molar ratio of the ammonium cation to the styrenesulfonic acid unit was 1.01 by H-NMR (the theoretical molar ratio of the ammonium cation to the styrenesulfonic acid unit in pure AmSS was 1.00), and thus it was judged that the wet crystal was the AmSS composition as the target.

[0356] The AmSS content, i.e., the purity, of the above AmSS composition was 89.2% by redox titration (the yield based on the raw material LiSS was 77%). As summarized in Table 6, the purity of the AmSS composition was equivalent to that of Examples 1 to 4 (Table 1), but did not contain 4-methoxyphenol, and thus the storage stability was significantly inferior to that of Examples 1 to 4.

[0357] <Comparative Example 9> Production of AmSS using LiSS and ammonium sulfate (2)

[0358] In Comparative Example 9, the inorganic ammonium salt species, the charge, and the temperature conditions were changed to those shown in Table 6, and 4-methoxyphenol was added, and the production of AmSS was performed. According to the analysis results of the lithium content of the wet crystal, it was judged that the wet crystal was the AmSS composition. The dewatering property of the slurry was good, the moisture content of the AmSS composition was as low as 6.82% by weight, the halogen content was as low as 0.09% by weight, and the purity was as high as 92.5%, which was equivalent to that of Examples 1 to 4.

[0359] The 4-methoxyphenol content in the above AmSS composition was 805 ppm, and the spontaneous polymerization at the time of storage at 60°C was suppressed as in Examples 1 to 4, but the APHA value increased. The reason was not clear, but it was presumed to be related to some kind of interaction with the lithium cation and 4-methoxyphenol.

[0360] <Comparative Example 10> Production of AmSS using LiSS and ammonium sulfate (3)

[0361] In Comparative Example 10, the species and the amount of the polymerization inhibitor were changed to those shown in Table 6, and the production of AmSS was performed. According to the analysis results of the lithium content of the wet crystal, it was judged that the wet crystal was the AmSS composition. The dewatering property of the slurry was good, the moisture content of the AmSS composition was as low as 6.91% by weight, the halogen content was as low as 0.08% by weight, and the purity was as high as 92.6%, which was equivalent to that of Examples 1 to 4.

[0362] The methoxyphenol content in the above AmSS composition was 420 ppm, and the nitrous acid content was 72 ppm. The natural polymerizability at 60°C was inhibited as in Examples 1 to 4, but the APHA value increased. The reason is not clear, but it is presumed to be related to some interaction of lithium cations, 4-methoxyphenol, and nitrous acid anions.

[0363] [Table 6]

[0364]

[0365] * AmSS composition (as is) 10 wt% aqueous solution

[0366] Comparative Example 11 Example 1 of Japanese Patent Application Publication No. 50-149642

[0367] In a 1 L four-necked flask equipped with a condenser, methanol 500.00 g, NaSS powder 25.01 g, and ammonium sulfate 25.02 g were charged, and heated in a bath at 65°C for 3 hours with stirring by a magnetic stirrer. The system was in a slightly turbid state, and the raw materials were substantially dissolved (the charge ratio of ammonium cations to NaSS was 3.54 equivalents, and the total solid content was 8.79 wt%). Then, when cooled to 30°C, a solid which was considered to be sodium sulfate was precipitated. The reaction solution was suction-filtered using a circulating aspirator, and the precipitate was filtered out. The filtrate was concentrated to dryness using a rotary evaporator at 50°C for 2 hours, and thus 21.53 g of a dry powder (AmSS) was obtained. Figure 6 The moisture content was 0.50 wt%.

[0368] Next, the active vinyl group of the above dry powder was quantified by redox titration. As a result, the purity was 98.0% assuming that the dry powder was AmSS. However, the sodium content calculated by ICP was 5.3 wt% (the theoretical Na content in pure NaSS was 11.1 wt%), the nitrogen content calculated by elemental analysis was 3.4 wt% (the theoretical nitrogen content in pure AmSS was 7.0 wt%), and the molar ratio of ammonium cations to styrene sulfonic acid units calculated by H-NMR was 0.54 (the theoretical molar ratio of ammonium cations to styrene sulfonic acid units in pure AmSS was 1.00 ( 1 H-NMR was 0.54 (the theoretical molar ratio of ammonium cations to styrene sulfonic acid units in pure AmSS was 1.00 ( Figure 5 Thus, about 50% of the above dry powder was NaSS, and the cation exchange rate was calculated to be about 50%.

[0369] As a reason why the cation exchange rate is low even though 3.54 equivalents of excess ammonium cations are added relative to the raw material NaSS, it is considered that the cause lies in the fact that the degree of ion dissociation of each salt in methanol is not sufficient, and the solubility of each salt in methanol is not so different. Furthermore, in this method, even if the impurity NaBr in NaSS is converted to ammonium bromide by cation exchange, the ammonium bromide dissolves in methanol, and thus the bromine cannot be removed. In fact, it was confirmed that the halogen component in the above-described dried powder was 1.27% by weight, which was more than 15 times as much as in Examples 1 to 4.

[0370] Although the above-described dried powder has little moisture, it does not contain 4-methoxyphenol, and thus the storage stability is poorer than in Examples 1 to 4.

[0371] Furthermore, the median particle diameter of the above-described dried powder is 11 μm, which is very small, and the dusting property is significantly strong compared to Examples 1 to 4.

[0372] Furthermore, the charged electric quantity per unit mass of this dried powder is 0.110 μC / g, which is larger than in Examples 1 to 5, and thus it is considered that the flying property is high, and the risk of dust explosion is also high.

[0373] [Table 7]

[0374]

[0375] AmSS composition (as is) 10% by weight aqueous solution

[0376] <Example 7> Production of AmSS using NaSS and ammonium sulfate (10) ETPE

[0377] Into a cylindrical 0.5 L separable glass flask equipped with a reflux condenser, 73.01 g of ammonium sulfate and 255.00 g of ion exchange water were charged, and dissolved while heating to an internal temperature of 40°C with stirring. After confirming the dissolution of the ammonium sulfate, 115.03 g of NaSS powder and 0.70 g of 4-ethoxyphenol were added to the reactor, and a cation exchange reaction was performed while stirring at an internal temperature of 48°C for 60 minutes. Then, it was cooled to 25°C over 5 hours, and left in this state for 2 hours for maturation, and a white slurry liquid was obtained.

[0378] Next, the above-described slurry liquid was subjected to centrifugal filtration (600 G x 20 minutes, room temperature), and thus a plate-shaped wet crystal 82.85 g was obtained. The dewatering property of the slurry was good, and the moisture of this wet crystal was 5.97% by weight as measured using an infrared moisture meter.

[0379] The above-described wet crystal was dried using a rotary evaporator at 40°C for 30 minutes (pressure 660 Pa), and a dried crystal 77.82 g (moisture 0.41% by weight) was obtained.

[0380] From the results of analysis of the sodium and nitrogen contents in the dried crystal (Table 8), it was determined that the dried crystal was the AmSS composition as the target.

[0381] The AmSS content, i.e., the purity, of the above dried crystal was 97.9% by weight (yield: 77% on a raw material NaSS molar basis) as determined by redox titration.

[0382] It was confirmed that the alkali metal component, the halogen component, and the polymer component in the AmSS composition were less than those in Comparative Examples 1 to 2, Comparative Examples 4 to 5, Comparative Example 7, and Comparative Example 11 (Tables 5 and 7), and that the purity was high.

[0383] In addition, the median particle diameter of the AmSS was 362 μm, which was much larger than 11 μm shown in Comparative Example 11 (Table 7), and thus it was expected that the dust raising property was lower than that of Comparative Example 11.

[0384] In addition, it was confirmed that the AmSS composition had less moisture and contained 169 ppm of 4-ethoxyphenol, and thus had excellent storage stability as compared with Comparative Examples 1 to 4 and Comparative Examples 6 to 7 (Table 5). It was also confirmed that the lithium component and the nitrous acid component were less, and thus the AmSS composition was less likely to be colored as compared with Comparative Examples 8 to 10 (Table 6).

[0385] In addition, the charged electric quantity per unit mass of the AmSS composition was 0.090 μC / g, which was slightly lower than that of Comparative Example 11 (Table 7) having a small particle diameter.

[0386]

[0387] The polymerization inhibitor was changed to 4-tert-butylcatechol, and the amount of addition was reduced, and otherwise, the AmSS was produced under the same conditions as in Example 7, and as a result, a wet crystal 83.83 g in a plate shape was obtained. The dewatering property of the slurry was good, and the moisture of the wet crystal was 7.16% by weight as determined by an infrared moisture meter. The wet crystal was dried using a rotary evaporator, and a dried crystal 77.9 g (moisture: 0.37% by weight) was obtained.

[0388] From the results of analysis of the sodium and nitrogen contents in the dried crystal (Table 8), it was determined that the dried crystal was the AmSS composition as the target.

[0389] The AmSS content, i.e., the purity, of the above dried crystal was 97.9% by weight (yield: 77% on a raw material NaSS molar basis) as determined by redox titration.

[0390] ​It was confirmed that the alkali metal component, the halogen component, and the polymer component in the AmSS composition were less than those in Comparative Examples 1 to 6, Comparative Example 7, and Comparative Example 11 (Tables 5 and 7), and that the AmSS composition was of high purity.

[0391] Further, the median particle diameter of the AmSS was 345 μm, which was much larger than 11 μm shown in Comparative Example 11 (Table 7), and thus it was expected that the dust raising property was lower than that of Comparative Example 11.

[0392] Further, it was confirmed that the AmSS composition had less moisture and contained 38 ppm of 4-tert-butylcatechol, and thus had excellent storage stability compared to Comparative Examples 8 to 10 (Table 6). It was also confirmed that the lithium component and the nitrous acid component were less, and the content of 4-tert-butylcatechol, which easily causes discoloration, was low, and thus the AmSS composition was less likely to be discolored compared to Comparative Examples 8 to 10 (Table 6).

[0393] Further, the electric charge amount per unit mass of the AmSS composition was 0.091 μC / g, which was slightly lower than that of Comparative Example 11 (Table 7) having a small particle diameter.

[0394] <Example 9> Production of AmSS using NaSS and ammonium sulfate (12) H-TEMPO

[0395] The polymerization inhibitor was changed to 4-hydroxy-2, 2, 6, 6-tetramethylpiperidine-1-oxyl radical, and otherwise, the AmSS was produced under the same conditions as in Example 8, and as a result, a plate-like wet crystal 85.74 g was obtained. The dewatering property of the slurry was good, and the moisture content of the wet crystal was 7.91% by weight as measured by an infrared moisture meter. The wet crystal was dried using a rotary evaporator, and a dried crystal 79.28 g (moisture content: 0.40% by weight) was obtained.

[0396] From the results of analysis of the sodium and nitrogen contents in the dried crystal (Table 8), it was determined that the dried crystal was the AmSS composition as the target product.

[0397] The AmSS content, i.e., the purity of the dried crystal was 97.8% by weight as measured by oxidation-reduction titration (yield: 78% on a raw material NaSS molar basis).

[0398] It was confirmed that the alkali metal component, the halogen component, and the polymer component in the AmSS composition were less than those in Comparative Examples 1 to 2, Comparative Examples 4 to 5, Comparative Example 7, and Comparative Example 11 (Tables 5 and 7), and that the AmSS composition was of high purity.

[0399] Further, the median particle diameter of the AmSS was 345 μm, which was much larger than 11 μm shown in Comparative Example 11 (Table 7), and thus it was expected that the dust raising property was lower than that of Comparative Example 11.

[0400] Further, it was confirmed that the AmSS composition had a small amount of water and contained 4-hydroxy-2, 2, 6, 6-tetramethylpiperidine-1-oxyl radical having a high polymerization inhibition ability of 43 ppm, and thus had excellent storage stability compared to Comparative Examples 1 to 4 and Comparative Examples 6 to 7 (Table 5). Further, it was confirmed that the AmSS composition had a small amount of lithium component and nitrous acid component, and had a low content of 4-hydroxy-2, 2, 6, 6-tetramethylpiperidine-1-oxyl radical that is colored, and thus was less likely to be colored compared to Comparative Examples 8 to 10 (Table 6).

[0401] Further, the AmSS composition had a charge amount of 0.091 μC / g per unit mass, which was slightly lower than that of Comparative Example 11 (Table 7) having a small particle size.

[0402] [Table 8]

[0403]

[0404] * ETPE: 4-ethoxyphenol, TBC: 4-tert-butylcatechol

[0405] H-TEMPO: 4-hydroxy-2, 2, 6, 6-tetramethylpiperidine-1-oxyl radical

[0406] ** AmSS composition (as is) 10 wt% aqueous solution

[0407] Example 10: Production of AmSS using NaSS and ammonium nitrate (1) H-TEMPO

[0408] A 0.5 L cylindrical separable glass flask equipped with a reflux condenser was charged with 89.00 g of ammonium nitrate and 285.00 g of ion exchange water, and the ammonium nitrate was dissolved while heating to an internal temperature of 40°C with stirring. After confirming dissolution of the ammonium nitrate, 115.04 g of NaSS powder and 0.25 g of 4-hydroxy-2, 2, 6, 6-tetramethylpiperidine-1-oxyl radical were added to the reactor, and a cation exchange reaction was performed while stirring at an internal temperature of 50°C for 30 minutes. Then, the temperature was allowed to cool to 20°C over 5 hours, and the slurry was allowed to stand for 2 hours for maturation, and a white slurry was obtained.

[0409] Next, the slurry was subjected to centrifugal filtration (600 G x 20 minutes, room temperature), and a wet crystal in the form of a plate was obtained in an amount of 81.75 g. The slurry was well dehydrated, and the moisture content of the wet crystal was 6.55 wt% as measured using an infrared moisture meter.

[0410] The wet crystal was dried using a rotary evaporator at 40°C for 30 minutes (pressure 660 Pa), and a dried crystal was obtained in an amount of 76.60 g (moisture content 0.85 wt%).

[0411] From the results of the analysis of the sodium and nitrogen contents in the dried crystals (Table 9), it was determined that the dried crystals were the AmSS composition as the target.

[0412] The AmSS content, i.e., the purity, of the above dried crystals was 96.5% by weight (yield: 75% on a raw material NaSS molar basis) as determined by oxidation-reduction titration.

[0413] It was confirmed that the alkali metal component, the halogen component, and the polymer component in the AmSS composition were less than those in Comparative Examples 1 to 2, Comparative Examples 4 to 5, Comparative Example 7, and Comparative Example 11 (Tables 5 and 7), and that the purity was high.

[0414] In addition, the median particle diameter of the AmSS was 374 μm, which was much larger than 11 μm shown in Comparative Example 11 (Table 7), and thus it was expected that the dust raising property was lower than that of Comparative Example 11.

[0415] In addition, it was confirmed that the moisture content of the AmSS composition was low, and that the 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl radical, which has a high polymerization inhibition ability, was contained at 49 ppm, and thus the storage stability was excellent as compared with Comparative Examples 1 to 4 and Comparative Examples 6 to 7 (Table 5). It was also confirmed that the lithium component and the nitrous acid component were less, and thus the coloring was less likely to occur as compared with Comparative Examples 8 to 10 (Table 6).

[0416] In addition, the charge amount per unit mass of the AmSS composition was 0.088 μC / g, which was slightly lower than that of Comparative Example 11 (Table 7) in which the particle diameter was small.

[0417] <Example 11> Production of AmSS using NaSS and ammonium nitrate (2) MEPE

[0418] Into a cylindrical 0.5 L separable glass flask equipped with a reflux condenser, ammonium nitrate 89.00 g and ion exchange water 239.70 g were charged, and dissolved with stirring while heating to an internal temperature of 40°C. After confirming the dissolution of the ammonium nitrate, NaSS powder 115.04 g and 4-methoxyphenol 1.20 g were added to the reactor, and a cation exchange reaction was performed with stirring at an internal temperature of 55°C for 30 minutes. Then, it was cooled to 20°C over 5 hours, and left to stand for 2 hours for maturation, and a white slurry liquid was obtained.

[0419] Next, the above slurry liquid was subjected to centrifugal filtration (600 G x 20 minutes, room temperature), and thus a wet crystal 91.32 g in the form of a plate was obtained. The slurry had good dewatering properties, and the moisture content of the wet crystal was 5.83% by weight as determined using an infrared moisture meter.

[0420] The above wet crystals were dried for 30 minutes at 40°C using a rotary evaporator (pressure 660 Pa) to obtain dried crystals 86.30 g (moisture content 0.88 wt%).

[0421] From the results of analysis of the sodium and nitrogen contents in the dried crystals (Table 9), it was determined that the dried crystals were an AmSS composition as the target.

[0422] The AmSS content, i.e., purity, of the above dried crystals was 96.7 wt% (yield 84% on a raw material NaSS molar basis) as determined by oxidation-reduction titration.

[0423] It was confirmed that the alkali metal component, halogen component, and polymer component in the AmSS composition were less than those in Comparative Examples 1 to 2, Comparative Examples 4 to 5, Comparative Example 7, and Comparative Example 11 (Tables 5 and 7) and were of high purity.

[0424] In addition, the median particle diameter of the AmSS was 341 μm, which was much larger than 11 μm shown in Comparative Example 11 (Table 7), and thus it was expected that the dust raising property would be lower than that of Comparative Example 11.

[0425] In addition, it was confirmed that the moisture content of the AmSS composition was low and that the composition contained 223 ppm of 4-methoxyphenol, and thus the storage stability was excellent compared to Comparative Examples 1 to 4 and Comparative Examples 6 to 7 (Table 5). It was also confirmed that the lithium component and nitrous acid component were low, and thus the composition was less likely to be colored than Comparative Examples 8 to 10 (Table 6).

[0426] In addition, the chargeable electric quantity per unit mass of the AmSS composition was 0.088 μC / g, which was slightly lower than that of Comparative Example 11 (Table 7) in which the particle diameter was small.

[0427] <Manufacture of AmSS using NaSS and ammonium nitrate (3) MEPE>

[0428] Into a cylindrical 0.5 L glass separable flask equipped with a reflux condenser, NaSS powder 103.00 g and 4-methoxyphenol 0.44 g and ion exchange water 142.00 g were charged, and slurrying was performed while heating to an internal temperature of 40°C with stirring. To the reactor, an ammonium nitrate aqueous solution (obtained by dissolving ammonium nitrate 105.00 g in ion exchange water 150.00 g) warmed to 40°C was added, and a cation exchange reaction was performed while stirring at an internal temperature of 51°C for 30 minutes. Then, it was cooled to 20°C over 5 hours, and aging was performed for 2 hours while maintaining the state, to obtain a white slurry solution.

[0429] Next, the slurry solution was centrifugally filtered (600 G x 20 minutes, normal temperature) to obtain a plate-like wet crystal 82.11 g. The slurry was well dewatered, and the moisture content of the wet crystal was 7.75% by weight as measured by an infrared moisture meter.

[0430] The wet crystal was dried at 40°C for 30 minutes (pressure 660 Pa) using a rotary evaporator to obtain a dried crystal 76.41 g (moisture content 1.62% by weight).

[0431] From the results of analysis of the sodium and nitrogen contents in the dried crystal (Table 9), it was determined that the dried crystal was an AmSS composition as the target.

[0432] The AmSS content, i.e., the purity of the dried crystal, as measured by redox titration was 94.5% by weight (yield 81% on a raw material NaSS molar basis).

[0433] It was confirmed that the alkali metal component, the halogen component, and the polymer component in the AmSS composition were less than those in Comparative Examples 1 to 2, Comparative Examples 4 to 5, Comparative Example 7, and Comparative Example 11 (Tables 5 and 7), and that the AmSS composition was of high purity.

[0434] Further, the median particle diameter of the AmSS was 390 μm, which was much larger than 11 μm shown in Comparative Example 11 (Table 7), and thus it was expected that the dust raising property would be lower than that of Comparative Example 11.

[0435] Further, it was confirmed that the AmSS composition had a low moisture content and contained 280 ppm of 4-methoxyphenol, and thus had excellent storage stability as compared with Comparative Examples 1 to 4 and Comparative Examples 6 to 7 (Table 5). It was also confirmed that the lithium component and the nitrous acid component were less, and thus the AmSS composition was less likely to be colored as compared with Comparative Examples 8 to 10 (Table 6).

[0436] Further, the charge amount per unit mass of the AmSS composition was 0.084 μC / g, which was slightly lower than that of Comparative Example 11 (Table 7) having a small particle diameter.

[0437] <Example 13> Production of AmSS using NaSS and ammonium nitrate (4) MEPE

[0438] A 0.5 L cylindrical glass separable flask equipped with a reflux condenser was charged with NaSS powder 115.04.00 g, 4-methoxyphenol 0.49 g, and ion exchange water 115.00 g, and slurry was performed under stirring while heating to an internal temperature of 40°C. To the reactor was added an ammonium nitrate aqueous solution (obtained by dissolving ammonium nitrate 89.00 g in ion exchange water 90 g) warmed to 40°C, and a cation exchange reaction was performed under stirring at an internal temperature of 60°C for 60 minutes. Then, it was cooled to 20°C over 5 hours, and left to stand for 2 hours for maturation, to obtain a white slurry liquid.

[0439] Next, the slurry liquid was subjected to centrifugal filtration (600 G x 20 minutes, room temperature), to obtain a plate-shaped wet crystal 99.74 g. The slurry was well dehydrated, and the moisture content of the wet crystal was 7.45% by weight as measured by an infrared moisture meter.

[0440] The wet crystal was dried using a rotary evaporator at 40°C for 30 minutes (pressure 660 Pa), to obtain a dried crystal 93.48 g (moisture content 1.31% by weight).

[0441] From the results of analysis of the sodium and nitrogen contents in the dried crystal (Table 9), it was determined that the dried crystal was an AmSS composition as the target.

[0442] The AmSS content, i.e., the purity of the dried crystal, was 95.3% by weight as measured by redox titration (yield 90% on a raw material NaSS molar basis).

[0443] It was confirmed that the alkali metal component, the halogen component, and the polymer component in the AmSS composition were less than those in Comparative Examples 1 to 2, Comparative Examples 4 to 5, Comparative Examples 6 to 7, and Comparative Example 11 (Tables 5 and 7), and that the purity was high.

[0444] In addition, the median particle diameter of the AmSS was 386 μm, which was much larger than 11 μm shown in Comparative Example 11 (Table 7), and thus it was expected that the dust raising property was lower than that of Comparative Example 11.

[0445] In addition, it was confirmed that the moisture content of the AmSS composition was low, and that 4-methoxyphenol was contained at 412 ppm, and thus the storage stability was excellent compared to Comparative Examples 1 to 4 and Comparative Examples 6 to 7 (Table 5). In addition, it was confirmed that the lithium component and the nitrous acid component were low, and thus the AmSS composition was less likely to be colored than Comparative Examples 8 to 10 (Table 6).

[0446] In addition, the charge amount per unit mass of the AmSS composition was 0.079 μC / g, which was slightly lower than that of Comparative Example 11 (Table 7) in which the particle diameter was small.

[0447] (5) MEPE

[0448] Into a cylindrical 0.5 L separable flask equipped with a reflux condenser, 115.01 g of NaSS powder, 1.20 g of 4-methoxyphenol, 89.00 g of ammonium nitrate, and 165.00 g of ion exchange water were charged, and a cation exchange reaction was performed while stirring at an internal temperature of 60°C for 60 minutes. Then, it was cooled to 20°C over 5 hours, and left to stand for 2 hours for maturation, to obtain a white slurry liquid.

[0449] Next, the slurry liquid was subjected to centrifugal filtration (600 G x 20 minutes, room temperature), to obtain 110.00 g of a plate-shaped wet crystal, but the slurry had poor dewatering properties, and the moisture content of the wet crystal was 15.50% by weight as measured by an infrared moisture meter.

[0450] The wet crystal was dried at 40°C for 30 minutes using a rotary evaporator (pressure 660 Pa), to obtain 92.67 g of a dried crystal (moisture content 1.98% by weight).

[0451] The AmSS content, i.e., the purity of the dried crystal was 92.7% by weight (yield 95% on a raw material NaSS molar basis) as measured by redox titration, and the sodium content was 0.65% by weight as measured by ICP, which was significantly more than in Example 13. The reason for this is that the total solid content was too high at the time of the reaction.

[0452] Furthermore, the charged electric amount per unit mass of the AmSS composition was 0.078 μC / g, which was slightly lower than in Comparative Example 11 (Table 7) in which the particle size was small.

[0453] [Table 9]

[0454]

[0455] H-TEMPO: 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl

[0456] MEPE: 4-methoxyphenol

[0457] **AmSS composition (as is) 10% by weight aqueous solution

[0458] In a 100-ml stoppered Erlenmeyer flask, the AmSS composition obtained in Example 1, 3, 10 and Comparative Example 11 above and N-methylpyrrolidone were taken in the compositions shown in Table 10, and the AmSS composition was dissolved with a magnetic stirrer while being immersed in a hot water bath at 35°C. After confirming dissolution visually, the solution was immediately filtered using a Buchner funnel (ADVANTEC TOYO Co., Ltd. quantitative filter paper No. 5A, diameter 70 mm, operating pressure 3.0 kPa), and the filtration time at that time was measured.

[0459] As shown in Table 10, it was clear that the less the sodium component, the shorter the filtration time. That is, the less the metal component such as sodium, the more preferable in electronic material applications, and also advantageous in terms of filtration properties.

[0460] [Table 10]

[0461]

Claims

1. An ammonium styrene sulfonate composition having the following characteristics of 1 to 6, 1: The content of ammonium styrene sulfonate in the composition is 88.0% by weight or more; 2: The content of water in the composition is 10.00% by weight or less; 3: The content of alkali metal in the composition is 0.50% by weight or less; 4: The content of halogen in the composition is 1.00% by weight or less; 5: The content of polymer in the composition is 0.20% by weight or less; and 6: The content of polymerization inhibitor in the composition is 2000 ppm or less.

2. The ammonium styrene sulfonate composition according to claim 1, wherein, 1: The content of ammonium styrene sulfonate in the composition is 88.0% by weight or more; 2: The content of water in the composition is 0.10 to 10.00% by weight; 3: The content of alkali metal in the composition is 0.50% by weight or less; 4: The content of halogen in the composition is 1.00% by weight or less; 5: The content of polymer in the composition is 0.20% by weight or less; and 6: The content of polymerization inhibitor in the composition is 20 to 2000 ppm.

3. The ammonium styrene sulfonate composition according to claim 1, wherein, 1: The content of ammonium styrene sulfonate in the composition is 94.00% by weight or more; 2: The content of water in the composition is 0.10 to 6.00% by weight; 3: The content of alkali metal in the composition is 0.50% by weight or less; 4: The content of halogen in the composition is 0.10% by weight or less; 5: The content of polymer in the composition is 0.20% by weight or less; and 6: The content of polymerization inhibitor in the composition is 20 to 1000 ppm.

4. The ammonium styrene sulfonate composition according to any one of claims 1 to 3, wherein, The polymerization inhibitor is at least one selected from the group consisting of 2-methoxyphenol, 3-methoxyphenol, 4-methoxyphenol, 4-ethoxyphenol, 4-cyanophenol, 4-butoxyphenol, 3-ethoxyphenol, 2,5-dimethoxyphenol, 2,6-dimethoxyphenol, 2,6-di-tert-butylphenol, 2,4-di-tert-butylphenol, 2,6-di-tert-butyl-4-methylphenol, 4-tert-butylcatechol, hydroquinone, methylhydroquinone, 2-methoxyhydroquinone, tert-butylhydroquinone, N-nitrosophenylhydroxylamine ammonium salt, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl, 4-(2-hydroxypropoxy-3-(2-hydroxyethoxy))-2,2,6,6-tetramethylpiperidine-1-ol, 4-(3-hydroxypropoxy-2-(2-hydroxyethoxy))-2,2,6,6-tetramethylpiperidine-1-ol, and salicylic acid hydrazide.

5. The ammonium styrene sulfonate composition according to any one of claims 1 to 3, wherein, The polymerization inhibitor is at least one phenolic compound selected from the group consisting of 2-methoxyphenol, 3-methoxyphenol, 4-methoxyphenol, 4-ethoxyphenol, 4-cyanophenol, 4-butoxyphenol, 3-ethoxyphenol, 2,5-dimethoxyphenol, and 2,6-dimethoxyphenol.

6. The ammonium styrene sulfonate composition according to any one of claims 1 to 3, wherein, The amount of electric charge per unit mass is 0.020 μC / g to 0.200 μC / g.

7. The ammonium styrenesulfonate composition according to any one of claims 1 to 3, wherein The median particle size of the crystals in the composition is 30 μm to 700 μm.

8. The ammonium styrenesulfonate composition according to any one of claims 1 to 3, wherein The median particle size of the crystals in the composition is 30 μm to 500 μm.

9. The ammonium styrenesulfonate composition according to any one of claims 1 to 3, wherein When the composition was stored in a sealed state at 60° C. for 60 days, the polymer content in the composition was 0.20% by weight or less.

10. The ammonium styrenesulfonate composition according to any one of claims 1 to 3, wherein The powder X-ray diffraction pattern measured by irradiation with copper Kα X-rays has diffraction peaks at least at diffraction angles 2θ=8.1±0.2°, 15.2±0.2°, 18.4±0.2°, 20.6±0.2°, 24.2±0.2°, 32.5±0.2°, and 43.0±0.2°.

11. The ammonium styrenesulfonate composition according to any one of claims 1 to 3, wherein In the powder X-ray diffraction pattern measured by irradiation with copper Kα X-rays, there are diffraction peaks at least at diffraction angles 2θ = 8.1±0.2°, 15.2±0.2°, 15.4±0.2°, 18.4±0.2°, 20.1±0.2°, 20.6±0.2°, 20.8±0.2°, 24.2±0.2°, 25.8±0.2°, 27.5±0.2°, 30.5±0.2°, 32.5±0.2°, 37.5±0.2°, 43.0±0.2° and 49.6±0.2°.

12. A method for producing an ammonium styrenesulfonate composition, which is the method for producing an ammonium styrenesulfonate composition according to any one of claims 1 to 3, wherein: In the presence of a polymerization inhibitor in an amount of 7 mol % or less relative to the amount of sodium styrene sulfonate or potassium styrene sulfonate, sodium styrene sulfonate or potassium styrene sulfonate is brought into contact with an inorganic ammonium salt in water to carry out a cation exchange reaction, followed by cooling to precipitate crystals of ammonium styrene sulfonate, and filtering the crystals, wherein: The charging ratio of ammonium cation to styrene sulfonic acid alkali metal salt is 1.50 equivalents to 3.00 equivalents, The total solid content in the reaction system is 25.00 wt% to 50.00 wt%, The temperature at which sodium styrene sulfonate or potassium styrene sulfonate is brought into contact with the inorganic ammonium salt is 30° C. to 80° C., and The temperature for filtering out the precipitated crystals is 5°C to 30°C.

13. The method for producing the ammonium styrenesulfonate composition according to claim 12, wherein: In the presence of a polymerization inhibitor in an amount of 7 mol % or less relative to the amount of sodium styrene sulfonate or potassium styrene sulfonate, sodium styrene sulfonate or potassium styrene sulfonate is brought into contact with an inorganic ammonium salt in water to carry out a cation exchange reaction, followed by cooling to precipitate crystals of ammonium styrene sulfonate, and filtering the crystals, wherein: the loading ratio of the ammonium cation relative to the alkali metal styrene sulfonate is 1.50 equivalents to 3.00 equivalents, the total solid content in the reaction system is 25.00% by weight to 45.00% by weight, the temperature at which the sodium or potassium styrene sulfonate is contacted with the inorganic ammonium salt is 30°C to 80°C, and the temperature at which the precipitated crystals are filtered is 5°C to 30°C.

14. The method for producing an ammonium styrene sulfonate composition according to claim 12, wherein after the cation exchange reaction is performed by contacting the sodium or potassium styrene sulfonate with the inorganic ammonium salt in water in the presence of a polymerization inhibitor in an amount of 5% by mole or less relative to the amount of the sodium or potassium styrene sulfonate, the crystals of the ammonium styrene sulfonate are precipitated by cooling, and the crystals are filtered out, wherein the loading ratio of the ammonium cation relative to the alkali metal styrene sulfonate is 2.00 equivalents to 2.50 equivalents, the total solid content in the reaction system is 35.00% by weight to 45.00% by weight, the temperature at which the sodium or potassium styrene sulfonate is contacted with the inorganic ammonium salt is 40°C to 60°C, and the temperature at which the precipitated crystals are filtered is 15°C to 25°C.

15. The method for producing an ammonium styrene sulfonate composition according to claim 12, wherein the inorganic ammonium salt is at least one compound selected from the group consisting of ammonium chloride, ammonium sulfate, ammonium nitrate, and ammonium acetate.

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