Silicate mineral and method for producing same

Abstract

A silicate mineral having an average particle diameter of more than hundreds of nm and not containing impurities such as crystalline silica can be provided. The contents of the silicate mineral, the crystalline silica and the asbestos are all 0.1 wt% or less. The mineral preferably contains carbonate, and preferably has an average particle diameter of 100 nm or more. In addition, the minerals are suitably used in cosmetics, hygienic products, pharmaceuticals, and foods. A silicate mineral according to the present invention is obtained by subjecting a natural silicate mineral to warm water or hot water treatment or hydrothermal reaction treatment at a pH of 9.4 or less.

Description

Technical Field

[0001] This invention relates to silicate minerals and methods for their manufacture. Background Technology

[0002] Silicate compounds are abundant in minerals and widely used in cosmetics, food, pharmaceuticals, and industrial products. Deep underground, groundwater is heated by volcanic activity, becoming high-temperature, high-pressure hot water (subcritical / supercritical water), which dissolves rocks to form a supercritical aqueous solution. Near the surface, when depressurization and cooling occur, the solubility decreases, causing precipitation. This is the principle behind mineral vein formation. Observation of the composition of soil and sand on the ground reveals that silicate compounds are a major component. Silicate compounds include not only silicon dioxide (SiO2), but also calcium silicate, magnesium silicate, iron silicate, sodium silicate, and other minerals containing various metals such as Al, Ca, Fe, K, Na, and Mg, as well as minerals containing multiple metals, and their hydrates are also formed in large quantities.

[0003] Table 1 Classification of Silicate Minerals

[0004] Based on its precipitation principle, it naturally contains impurities. Among them, SiO2, a constituent component, is often included as an impurity.

[0005] The purpose of this invention is to remove impurities generated during the precipitation of silicate minerals, using aluminum silicate, calcium silicate, magnesium silicate, iron silicate, and their hydrates as examples. The following description uses hydrated magnesium silicate (also known as talc, etc.) as an example, but the principle is applicable to other silicate minerals as well.

[0006] Hydrous magnesium silicate is widely used in cosmetics, food, pharmaceuticals, and industrial products. However, as a natural mineral, it often contains impurities. In commercial applications, toxic substances and heavy metals are removed before reuse. Nevertheless, in many cases, materials like talc, a natural mineral, are prone to contamination with components such as SiO2, which are easily precipitated during mineral formation. These easily precipitated components often end up in the finished product. For example, small amounts of tremolite and chrysotile caused by asbestos are frequently present. Asbestos contamination is not only unacceptable in cosmetics, food, and pharmaceuticals but also in industrial products. Furthermore, the contamination of crystalline SiO2 (also known as crystalline silica, quartz, etc.) has recently become a problem.

[0007] However, the formation of minerals underground is a precipitation process influenced by temperature and pressure, and the composition of the precipitates varies depending on the mining location. Detailed investigation and selection of fractions virtually free of these impurities has always been the only solution, but even so, trace amounts of impurities are still common, particularly in applications such as medicine, food, and cosmetics, where this has become a significant problem.

[0008] Furthermore, if we focus on crystalline SiO2, since hydrated magnesium silicate and SiO2 have almost the same specific gravity and physical properties required for the separation of existing components, they cannot be separated by centrifugation, sedimentation, gravity separation, or adsorption operations such as chromatography.

[0009] Here, a method for artificially synthesizing microparticle-shaped talc using hydrothermal synthesis, including supercritical fields, has been proposed (see Patent Document 1).

[0010] Existing technical documents Patent documents Patent Document 1: Japanese Patent Publication No. 2014-520743 Summary of the Invention

[0011] However, the synthetic talc obtained by the method described in Patent Document 1 has a particle size as small as 20 nm to 100 nm. In practical applications of hydrated silica compounds such as talc, natural minerals are used after being crushed and sieved, resulting in particle sizes of tens of μm or larger, even in cases where the particle size is small, it is still above sub-μm. From the perspective of user safety (nanoscale risk), there is a desire to provide talc with larger particle sizes. In principle, particle size can be increased through hydrothermal methods, but artificial synthesis has problems in terms of manufacturing cost, production efficiency, and optimization of properties, making it practically impossible to use as an industrial method for producing particles larger than hundreds of nm.

[0012] Therefore, even when aiming to remove impurities from natural minerals, for crystalline silica, dissolving SiO2 impurities from a mixture of hydrated magnesium silicate and the impurity SiO2 means that setting alkaline conditions can dissolve the impurities, but simultaneously, the hydrated magnesium silicate will also dissolve. Therefore, the separation and removal of hydrated magnesium silicate while simultaneously dissolving and removing SiO2 impurities has not been studied. In principle, an industrial method requires conditions that dissolve only SiO2 without dissolving the hydrated magnesium silicate. However, considering that mineral formation in nature occurs simultaneously, and the mixing occurs precisely because the solubility is almost identical, exploring such conditions is extremely difficult.

[0013] Furthermore, asbestos is a type of serpentinite or amphibolite, which is generally not only heat-resistant but also stable to acids and alkalis. This means that under conditions where it can be dissolved and removed, other components, such as hydrated magnesium silicate, would also dissolve, making it extremely difficult to remove.

[0014] The present invention was made in view of the above-mentioned problems and is able to provide silicate minerals having an average particle size of more than several hundred nm and free from impurities such as crystalline silica.

[0015] Through repeated and in-depth research, the inventors discovered that by treating silicate minerals derived from natural minerals with warm or hot water or hydrothermal reaction at a pH below 9.4, toxic impurities such as crystalline silica or asbestos can be dissolved in water or removed through reaction modification, thus completing this invention. Specifically, this invention provides the following technical solution.

[0016] This invention relates to a method for manufacturing silicate mineral powder, comprising a step of treating silicate minerals derived from natural minerals with warm or hot water or hydrothermal reaction at a pH below 9.4. Furthermore, carbonic acid and other substances can coexist in the reaction environment, thereby controlling the pH to be low and simultaneously enabling the reaction modification and removal of impurities.

[0017] Hydrothermal reactions, exemplified by quartz, are widely used as a method for single-crystal growth of metal oxides. Under hydrothermal conditions, metal oxides repeatedly dissolve and precipitate, resulting in crystal growth. This crystal growth process is known as Ostwald ripening. Unstable microparticles and high-surface-energy tips dissolve more easily, allowing for single-crystal growth with more stable exposed surfaces. In fact, utilizing the mechanism and principles of Ostwald ripening to promote faster crystal growth has been industrially applied as a method for manufacturing large-size single crystals.

[0018] Since the solubility of metal oxides varies with temperature, faster crystal growth is typically achieved by creating a temperature distribution within the crystal grower to promote single crystal growth. Under subcritical hydrothermal and high-pressure supercritical conditions (high water density), a method is employed where the raw material is dissolved in a high-temperature field and the seed crystal grows in a low-temperature field. Conversely, under relatively low-pressure, low-density supercritical water conditions, precipitation occurs in a high-temperature (low water density) field, actively utilizing the readily occurring natural retention. This process typically takes only a few hours, generally several days to several weeks.

[0019] Considering the principle of Ostwald ripening, if talc and hydrated magnesium silicate of different particle sizes and shapes are subjected to hydrothermal ripening, both components will dissolve starting from tiny particles and pointed particles. This invention differs from crystal growth in that it does not focus on the growth of tremolite, chrysotile, or crystalline silica (quartz) that may be impurities, but rather on the dissolution or reactive modification of these impurities. While inhibiting the dissolution of silicate minerals, it selectively dissolves or reactively modifies impurities such as crystalline silica, thereby preparing silicate minerals whose main component is free of impurities represented by crystalline silica.

[0020] Furthermore, compared to the artificial synthesis of talc using hydrothermal synthesis, which can theoretically produce silicate minerals free of crystalline silica or chrysotile asbestos as impurities, this invention offers advantages in manufacturing costs. Additionally, since the raw material is a pulverized natural mineral, particles with diameters of several hundred nm or larger, in demand in the market, can be recovered.

[0021] Because it is a reaction site where Ostwald ripening occurs, the recovered silicate mineral particles have fewer particulates and are more rounded compared to typical natural mineral pulverizers. Additionally, the product surface has more hydroxyl groups.

[0022] The pH is below 9.4. While crystalline silica can dissolve at high pH, ​​silicate minerals also dissolve simultaneously. Normally, subcritical and supercritical hydrothermal synthesis (artificial synthesis) of silicate minerals is preferably performed at low pH. Since silicate minerals precipitate under these conditions, it is theoretically desirable to use conditions that dissolve only crystalline silica without dissolving silicate minerals.

[0023] This approach also applies to the removal of impurities such as chrysotile asbestos. Since chrysotile asbestos and other asbestos are alkaline minerals, it is theoretically possible to achieve this by setting conditions under hydrothermal conditions that do not result in a high pH, ​​allowing them to dissolve and silicate minerals to precipitate.

[0024] These impurities are particularly problematic when they are needle-shaped products, as they dissolve from their tips under hydrothermal conditions. Considering the dissolution rate and amount of a large quantity of silicate minerals, even if the same amount is dissolved, only a large quantity of existing silicate minerals will remain in the end.

[0025] To lower the pH, acids can coexist, or carbonic acid can be used as the acid. In this case, carbonates may sometimes form depending on the conditions. The following reaction is known as the mechanism of talc formation in the reaction field where minerals are formed deep underground.

[0026] This indicates that serpentine (chrysotile asbestos) reacts with CO2 under hydrothermal conditions to form talc. The magnesium in chrysotile asbestos precipitates as magnesium carbonate. However, since magnesium carbonate has a higher solubility under hydrothermal conditions than other products, it can also be removed by dissolving it through a semi-batch extraction process.

[0027] Furthermore, recent studies have reported the formation of carbonates from the reaction of calcium silicate and other compounds with CO2. Beyond the study of mineral formation mechanisms, research and development are underway to address CO2 issues, including solidification through carbonation of calcium silicate compounds (Goto et al., Inorganic Materials, Vol. 5, Jan. 22-27 (1998)), CO2 absorption in concrete (CO2-SUICOM process), and the synthesis of artificial marble by Professor Richard Riman of Rutgers University using a hydrothermal reaction with calcium silicate in the presence of CO2. These advancements represent practical applications of research and technology development aimed at solving CO2 problems. In other words, carbonate formation occurs under hydrothermal conditions in the presence of CO2.

[0028] On the other hand, in the field of geophysics, another known mechanism for the formation of underground talc is as follows.

[0029] The reaction mechanism involves the formation of talc under hydrothermal conditions through the coexistence of silica and silicon dioxide. As described above, this suggests that talc can be modified by reacting carbonates with silica.

[0030] That is, the tremolite mixed in as a trace component is Ca2(Mg,Fe)5Si8O 22 When trace amounts of tremolite are mixed into (OH)2 (where Mg / (Mg+Fe)=1.0-0.9), under hydrothermal conditions, it not only dissolves and is removed, but also undergoes carbonation in the presence of CO2. At the same time, silica, which also exists as an impurity, dissolves and reacts, thus being modified into talc.

[0031] Furthermore, in this invention, warm water or hot water treatment or hydrothermal reaction treatment is preferably carried out in the presence of Mg ions. When the mineral contains crystalline silica, etc., from an equilibrium perspective, the coexistence of Mg may also promote the formation of magnesium silicate. Simply put, a reaction of SiO2 and Mg complexation also exists. However, although in reality, the dissolution of silica and magnesium silicate allows Mg ions to coexist with Si ions, if magnesium ions are supplied, the dissolution equilibrium of silica and magnesium silicate can be shifted towards a direction where the dissolution of silica becomes dominant.

[0032] Silicate minerals, derived from natural minerals, are provided by crushing natural minerals. Therefore, it is difficult to achieve an average particle size of less than 200 nm, and even for products treated with hydrothermal reaction, the average particle size reaches more than 200 nm.

[0033] Therefore, according to the present invention, it is possible to provide talc with an average particle size greater than 100 nm and free from impurities such as crystalline silica or asbestos.

[0034] In addition, in this invention, it is preferred that the temperature in the warm water or hot water treatment or the hydrothermal reaction treatment is above 70°C and below 370°C, and the pressure is above the saturated vapor pressure of water.

[0035] According to the present invention, impurities such as crystalline silica or asbestos can be dissolved / reacted and removed using low-temperature thermal energy at temperatures below 370°C (preferably below 300°C, more preferably below 250°C, even more preferably below 200°C, and particularly preferably below 150°C), thus offering a greater advantage in terms of manufacturing costs. As for the low-temperature thermal energy, not only thermal energy from heat source devices can be considered, but also the reuse of waste heat within the factory.

[0036] This invention can be applied to any of the intermittent devices, semi-intermittent devices, and flow-through devices, but it is preferred to use a semi-intermittent device or a flow-through device for warm water or hot water treatment or hydrothermal reaction treatment, and even more preferably to use a semi-intermittent device for warm water or hot water treatment or hydrothermal reaction treatment.

[0037] The solubility of silica relative to pure water has been reported. However, in the hydrothermal treatment of this system containing minerals with other ions, the dissolution of these minerals also occurs, thus differing from the solubility of silica in high-temperature, high-pressure water. Typically, the solubility of a specific component or the concentration of dissolved chemical species in the presence of other minerals can be solved by simultaneously applying the dissolution equilibrium of all substances, and consequently the dissociation equilibrium of water and the charge balance. The required chemical equilibrium can be predicted with high accuracy using the HKF (Helgeson Kirkham Flouer) model or a modified HKF model developed by Sue et al., including the supercritical region.

[0038] (Sue, K., Hakuta, Y., Smith, RL, Adschiri, T., & Arai, K. (1999). Solubility of lead(II) oxide and copper(II) oxide in subcritical and supercritical water. Journal of Chemical & Engineering Data, 44(6), 1422-1426. https: / / doi.org / 10.1021 / je9901029) For example, the saturated solubility is further increased by adding alkalis or coexisting ions. Furthermore, it is evident that during the precipitation of minerals underground, when silica precipitates as an impurity, the precipitated minerals have low solubility and a high precipitation rate. This suggests that silica is readily soluble not only from the aforementioned equilibrium theory but also from a kinetic perspective. Although this has been experimentally verified, it sufficiently demonstrates that a dissolution rate more than 10 times faster can be achieved not only from equilibrium theory but also from a kinetic standpoint.

[0039] As a reaction system, the optimal value of the water flow rate during operation is determined by this equilibrium theory and dynamics.

[0040] By using a semi-batch system, heat recovery and preheating can also be performed in warm / hot water treatment or hydrothermal reaction processes, thus offering a cost advantage. Furthermore, since impurities such as extracted crystalline silica or asbestos can be removed from the system, contamination caused by their redeposition can be prevented.

[0041] When the reaction apparatus is a semi-batch system, the amount of aqueous solvent supplied to the semi-batch system is preferably at least 0.1 times the theoretical amount required to saturate the crystalline silica contained in the silicate minerals used as raw materials in the reaction field to the reaction solution containing coexisting ions. Alternatively, the amount of crystalline silica contained in the silicate minerals used as raw materials fed into the semi-batch system is preferably at least 10 times the theoretical amount required to saturate the reaction solution containing coexisting ions in the reaction field.

[0042] In a flow-through system, silicate minerals are supplied to water in a suspended state for warm or hot water treatment or hydrothermal reaction. Heat can be recovered at the outlet and used as preheating for the raw material. Unlike semi-batch systems, heat loss during heating and cooling of the extraction tank is eliminated, thus increasing the heat recovery rate. However, silica dissolved in the cooling section may reprecipitate in the subsequent cooling section. To avoid this, sufficient dissolution of crystalline silica and rapid cooling suppress the Ostwald ripening and recrystallization of residual silica. It should be noted that this condition can be studied through small-scale batch experiments.

[0043] Furthermore, the concentration of the silicate mineral slurry supplied to the flow-through device is preferably at least 0.1 times the theoretical amount of crystalline silica contained in the aforementioned silicate minerals as raw materials that is saturated and dissolved in the reaction solution containing coexisting ions in the reaction field.

[0044] According to the present invention, silicate minerals with an average particle size greater than several hundred nm and free from impurities such as crystalline silica can be provided. Attached Figure Description

[0045] Figure 1 This is a schematic diagram of the manufacturing apparatus 1 according to this embodiment.

[0046] Figure 2 The results are from X-ray diffraction tests of natural talc before hydrothermal reaction treatment.

[0047] Figure 3 The results are from X-ray diffraction tests on natural talc after hydrothermal reaction treatment. Detailed Implementation

[0048] The following describes specific embodiments of the present invention in detail. However, the present invention is not limited to any of the following embodiments. Within the scope of the present invention, appropriate modifications can be made to implement it.

[0049] <Apparatus for manufacturing hydrated magnesium silicate powder> Figure 1 This is a schematic diagram of apparatus 1 for manufacturing hydrated magnesium silicate powder.

[0050] The manufacturing apparatus 1 includes an extraction unit 10 and a cooling unit 20 as needed.

[0051] [Extraction Unit 10] Extraction unit 10 is an apparatus that brings the raw material liquid into contact with an aqueous material to treat the raw material with warm or hot water or to perform a hydrothermal reaction. Extraction unit 10 can be any of a batch, semi-batch, or continuous apparatus. However, it is preferable to use a batch or semi-batch apparatus for hydrothermal reaction treatments, which allows for lower temperatures and utilizes both heat from a heat source and waste heat from the plant, thus offering advantages in manufacturing cost. From this perspective, extraction unit 10 is preferably a batch or semi-batch apparatus, and more preferably a semi-batch apparatus for warm or hot water treatment or hydrothermal reaction treatment.

[0052] By using a semi-batch system, heat recovery and preheating can be performed in warm / hot water treatment or hydrothermal reaction processes, resulting in a cost advantage. Furthermore, since impurities such as extracted crystalline silica or asbestos can be removed from the system, contamination caused by their redeposition can be prevented.

[0053] Alternatively, the extraction unit 10 can also be a continuous process (flow-through process). When using a flow-through process, silicate minerals are supplied to water in a suspended state for warm or hot water treatment or hydrothermal reaction treatment. Heat can be recovered at the outlet and used as preheating of the raw material. Unlike semi-batch processes, heat loss during heating and cooling of the extraction tank is eliminated, thus increasing the heat recovery rate. However, silica dissolved in the cooling section may reprecipitate in the subsequent cooling section. To avoid this, sufficient dissolution of crystalline silica and rapid cooling suppress the Ostwald ripening and recrystallization of residual silica. It should be noted that this condition study can be conducted through small-scale batch experiments.

[0054] Unless otherwise specified, the following description will use extraction unit 10 as a semi-intermittent device, but it is not limited to this.

[0055] [raw material] The raw material fed into the extraction unit 10 is a silicate mineral, which can be from natural minerals or synthetic minerals, but is preferably a silicate mineral from natural minerals.

[0056] There are no particular limitations on the types of metals that make up silicate minerals. Besides alkali metals and alkaline earth metals, aluminum, iron, and other metals can also be listed. Specific examples of silicate minerals include aluminum silicate, magnesium silicate, calcium silicate, iron silicate, or silicate minerals containing multiple of these metals. Furthermore, silicate minerals can also be hydrated silicate minerals that are their hydrates.

[0057] For example, when silicate minerals are natural minerals such as talc (hydrated magnesium silicate), the asbestos (tremolite, chrysotile, etc.) content in natural minerals is specified to be 0.1% or less according to the Enforcement Ordinance of the Occupational Safety and Health Law (Showa 47 Government Ordinance No. 318) and the Asbestos Hazard Prevention Regulations (Heisei 17 Ministry of Health, Labour and Welfare Ordinance No. 21). Therefore, silicate minerals with a content of 0.1% or less are preferred as raw materials.

[0058] In addition, as a method for determining the asbestos content in talc using X-ray diffraction, the "Analytical Method for Asbestos Content in Natural Minerals" in Annex to Kian Chemical Development Document No. 0828001 is adopted. In this method, a general-purpose X-ray diffraction apparatus (XRD apparatus) is used, and the measurement conditions are as follows ("Analytical Method for Asbestos Content in Talc," Asbestos Analysis Handbook Based on Prior Survey of Asbestos Regulations, March 2013, Ministry of Health, Labour and Welfare): Tube voltage: 40kV and above Tube current: 30mA and above For cathode: Cu Monochromaticization: Graphite monochromator or Ni filter Detectors: scintillation counters, proportional counters, Geiger counters, semiconductor detectors, etc. Slit system: Light-receiving slit 0.3mm or 0.2mm Diverging slit: 1° Scattering slit: 1° Goniometer scanning speed: less than 1 / 8° per minute Time constant: Use an appropriate time constant.

[0059] Full scale of the chromatogram: Determine the intensity of the diffraction lines and calculate the net peak area after subtracting the background. Select the diffraction lines on the recording chart as the appropriate full scale for confirming the chromatographic peak.

[0060] Typically, in the determination of trace components, the chromatographic peak is sometimes masked by baseline noise, requiring an extended integration time to improve the signal-to-noise ratio. Therefore, trace detection is theoretically possible even without a powerful radiation source.

[0061] However, if the evaluation is performed within the measurement time typically used in crystal structure analysis, the integration time is insufficient to adequately detect the chromatographic peaks, potentially leading to the asbestos content being determined to be below 0.1% by weight, which is considered a safety benchmark.

[0062] In the invention described in this embodiment, long-term measurements are conducted with full consideration of this aspect, and the results are analyzed using a standard curve based on a precise baseline evaluation. Asbestos is removed through reactive modification, bringing the asbestos content to a true level of 0.1% by weight or less, as specified in Annex No. 0828001 of the Chemical Industry and Information Technology Department of Anhui Province. Based on the results determined by a widely used X-ray diffraction apparatus, and using precise analytical methods, it is confirmed with sufficiently high accuracy that the safety standards in that annex have been met.

[0063] [Dispersion medium] In addition, the dispersion medium for the dispersed raw materials is an aqueous material. Aqueous materials refer to water, polar organic solvents, or mixtures of water and polar organic solvents. Examples of aqueous materials include: water, alcohols, carboxylic acids, ketones, ethers, esters, amides, amines, sulfur compounds, and mixtures thereof.

[0064] Examples of alcohols include methanol, ethanol, isopropanol, tert-butanol, propylene glycol, and phenol.

[0065] As carboxylic acids, examples include: formic acid, acetic acid, propionic acid, butyric acid, valeric acid, hexanoic acid, and other lower carboxylic acids.

[0066] Examples of ketones include acetone, methyl ethyl ketone, and methyl isobutyl ketone.

[0067] Examples of ethers include: ethylene glycol monobutyl ether, ethylene glycol monoethyl ether, tetrahydrofuran, dioxane, and methyl cellosolve, etc.

[0068] Examples of esters include ethyl acetate and butyl acetate.

[0069] Examples of amides include: formamide, dimethylformamide, acetamide, dimethylacetamide, nitromethane, and acetonitrile.

[0070] Examples of amines include: methylamine, ethylamine, trimethylamine, triethylamine, monoethanolamine, diethanolamine, triethanolamine, pyridine, ethylenediamine, hexamethylenediamine, etc.

[0071] Examples of sulfur compounds include dimethyl sulfoxide.

[0072] For ease of operation, the water-based material preferably contains one or more of water, alcohols, and carboxylic acids, and more preferably water.

[0073] In addition, pH adjusters and oxidizing / reducing agents can be added to the aqueous materials to control the reaction field.

[0074] Examples of pH adjusters include: hydrochloric acid, nitric acid, acetic acid, sulfuric acid, carbonic acid or their ammonium salts as acids, and potassium hydroxide, sodium hydroxide, calcium hydroxide, magnesium hydroxide, aluminum hydroxide or ammonia as bases.

[0075] Examples of oxidizing / reducing agents include: hydrogen peroxide, oxygen, nitric acid, formic acid, hydrazine, hydrogen, ammonia, ethanol, and formaldehyde.

[0076] These substances are not only related to the solubility of the target impurity, but can also function as reactive substances.

[0077] For example, carbonates can be generated by coexisting carbonic acid or CO2 in aqueous materials, and further modification from toxic impurity minerals to non-toxic carbonated minerals or talc can sometimes occur through reaction with silica.

[0078] Furthermore, it is preferable to add Mg ions to the water-based materials. Therefore, subsequent warm or hot water treatment or hydrothermal reaction treatment can be carried out in the presence of Mg ions.

[0079] When minerals contain crystalline silica, the coexistence of Mg and other elements can theoretically promote the formation of magnesium silicate. In simpler terms, a reaction involving the recombination of SiO2 and Mg also occurs. However, while the dissolution of silica and magnesium silicate allows Mg and Si ions to coexist, the supply of magnesium ions can shift the dissolution equilibrium between silica and magnesium silicate towards a predominance of silica dissolution. Therefore, the addition of Mg ions to aqueous materials is preferred.

[0080] [Raw Material Solution] In this embodiment, a raw material liquid prepared by dispersing the raw materials using a dispersion medium is fed into the extraction unit 10. The raw material liquid can be fed in the form of a powder or a flowing fluid. There are no particular limitations as long as it is flowing; examples include aqueous solutions, slurries, pastes, or suspensions containing the raw material components.

[0081] In addition, when it is difficult to prepare an aqueous slurry, the raw materials can be dispersed in an aqueous material such as ethanol to form a slurry.

[0082] When the reaction apparatus is a semi-batch system, the amount of aqueous solvent supplied to the semi-batch system is preferably 0.1 times or more, more preferably 0.3 times or more, even more preferably 0.5 times or more, and even more preferably 0.8 times or more, relative to the theoretical amount of crystalline silica contained in the silicate minerals used as raw materials for saturation dissolution in the reaction solution containing coexisting ions in the reaction field. Alternatively, the amount of crystalline silica contained in the silicate minerals used as raw materials fed into the semi-batch system is preferably 10 times or less, more preferably 3.5 times or less, even more preferably 2 times or less, and even more preferably 1.3 times or less, relative to the theoretical amount of crystalline silica contained in the reaction solution containing coexisting ions in the reaction field for saturation dissolution.

[0083] In this specification, the amount of crystalline silica is preferably at least 0.1 times the theoretical amount required for saturation dissolution in a reaction solution containing coexisting ions in the reaction field. From a purely chemical equilibrium perspective, a suitable amount of crystalline silica exceeding the theoretical amount of water for saturation dissolution offers limited flexibility. However, in this invention, reaction kinetics play a more dominant role than chemical equilibrium, taking advantage of silica's greater solubility than talc. For example, the chemical equilibrium changes upon the addition of a base or Mg ions. Furthermore, since crystalline silica dissolves faster than other minerals such as talc, it is kinetically advantageous in semi-batch, flow-through processes, or short-duration batch processes; therefore, a smaller amount of crystalline silica than the theoretical amount of water for saturation dissolution is acceptable. Thus, the amount of crystalline silica is highly flexible, requiring only at least 0.1 times the theoretical amount.

[0084] When the extraction unit 10 is a flow-through device, the concentration of the silicate mineral slurry supplied to the flow-through device is preferably 0.1 times or more the theoretical amount of crystalline silica contained in the silicate mineral as raw material to be saturated and dissolved in the reaction solution containing coexisting ions in the reaction field. More preferably, it is 0.3 times or more, even more preferably 0.5 times or more, and even more preferably 0.8 times or more.

[0085] Furthermore, in this invention, the theoretical amount of saturated dissolution of the reaction solution containing coexisting ions relative to the reaction field can be determined using the HKF (Helgeson Kirkham Flouer) model. The solubility evaluation method is as described above.

[0086] The pH of the feed solution fed into the extraction unit should be below 9.4. If the pH exceeds 9.4, even if hydrothermal treatment is carried out using hydrated magnesium silicate from natural minerals as a feedstock, it may not be possible to fully dissolve the crystalline silica that may be present in the feedstock, so this is not preferred.

[0087] To better dissolve impurities in the solvent, the upper limit of pH is preferably 7 or less. Furthermore, from the viewpoint of modifying the aqueous material by causing the coexistence of carbonic acid or CO2, resulting in the formation of talc from impurity minerals, pH is more preferably 6 or less, and even more preferably 5 or less.

[0088] The lower limit of pH is not particularly limited, but from the viewpoint of suppressing corrosion of the apparatus, which is mainly composed of extraction unit 10, the lower limit of pH is preferably 1 or more, and more preferably 2 or more. Furthermore, from the viewpoint of modifying the formation of talc from impurity minerals by allowing the coexistence of carbonic acid or CO2 in the aqueous material, pH is more preferably 3 or more, and even more preferably 4 or more.

[0089] There is no particular limitation on the timing of the coexistence of acid and alkali, as long as the raw material liquid is in an acid-alkali coexistence state before contact with the aqueous material in the extraction unit 10. However, in order to simplify the structure of the manufacturing apparatus 1, it is preferable to supply acid or alkali during the raw material conditioning stage to make the raw material liquid acidic or alkaline.

[0090] While not strictly necessary, the feed liquid is preferably a degassed feed liquid. Examples of degassed devices for the feed liquid include: degassed devices using ultrasound, degassed devices that reduce pressure, degassed devices that introduce rare gases into the feed liquid, degassed devices using permeable membranes, and other existing degassed devices, as well as degassed devices combining these existing degassed devices. Degasting the feed liquid suppresses corrosion of the extraction unit 10 and cooling unit 20 caused by dissolved oxygen.

[0091] [Supply of Water System Materials] Next, the water-based materials continuously supplied to the extraction unit 10 will be described.

[0092] As types of water-based materials, the materials described above as dispersion media can be listed.

[0093] While not strictly necessary, the aqueous material is preferably a degassed aqueous material. Examples of degassed aqueous materials include the apparatus described previously for degasing raw materials. Degasting the aqueous material suppresses fluctuations in its supply caused by bubbles generated from dissolved gases. Furthermore, it suppresses corrosion of the extraction unit 10 and cooling unit 20 caused by dissolved oxygen. In addition, dissolved oxygen affects the redox state of the hydrothermal treatment reaction field, and the presence of gases such as CO2, which significantly influence the modification reaction under hydrothermal conditions, is also a crucial factor for controlled processing.

[0094] The aqueous material is under pressure by a booster pump or similar means. By pressurizing and further heating the aqueous material to bring it to a subcritical state, the aqueous material can be continuously supplied to the extraction unit 10.

[0095] The pressurized aqueous material is preferably hot water or a subcritical aqueous material. When the aqueous material is water, subcritical water has a high solubility for silica. Therefore, pressurized liquid water (liquid phase) is preferred, or water containing a liquid phase as the main phase. However, even water in the gaseous phase or in the state of water vapor (or steam) sometimes forms a condensed phase between particles due to capillary forces, exhibiting the same behavior as liquid water, so these states of water are also included. In addition, if the aqueous material is supercritical, high density is required to exhibit high solubility, which requires pressures above the critical pressure, which is not ideal for large-scale industrial production. Furthermore, compared to the pre-critical state, the amount of hydroxyl groups generated on the surface of the raw material is less, affecting the dissolution of crystalline silica or asbestos that may be present in the raw material.

[0096] In this invention, "warm water conditions, hot water conditions, or hydrothermal conditions" are defined as water coexistence conditions of a liquid with a reaction temperature of 70°C or higher and 370°C or lower. However, when particles are used as the object, since there is also a reaction and dissolution in the condensation state caused by capillary forces between particles, in this special case, the supply system can also be a water coexistence condition in the gas phase, referred to as water vapor (or steam).

[0097] The pressure of the pressurized aqueous material should be above the saturated vapor pressure. If it is below the saturated vapor pressure, even if the raw material liquid is brought into contact with the pressurized aqueous material, it may not be possible to fully dissolve or react and remove impurities such as crystalline silica or asbestos that may be present in the raw material, so it is not preferred.

[0098] However, as a special case, small particle sizes, where capillary forces between particles play a role, sometimes exhibit the same dissolving effect even on water in a state below saturated vapor pressure, which is known as water vapor (or steam).

[0099] To more effectively remove impurities such as crystalline silica or asbestos that may be present in the raw materials, the pressure of the pressurized aqueous material is preferably above the saturated vapor pressure at the treatment temperature. For example, it is 0.2 MPa or higher at a treatment temperature of 120°C, and 0.8 MPa or higher at 170°C. The pressure is lower at low temperatures and higher at high temperatures, reaching 22.1 MPa or higher at the critical point of 374°C. The pressure of the pressurized aqueous material is preferably 0.2 MPa or higher, more preferably 0.5 MPa or higher, and even more preferably 1 MPa or higher. Even at lower temperatures, such as 70°C, solubility decreases, thus reducing treatment efficiency and speed, but the same removal effect can theoretically be expected. In this case, since it is 0.03 MPa, below atmospheric pressure, warm water treatment can be performed even when operating at normal pressure.

[0100] Furthermore, the pressure of the pressurized aqueous material is below 40 MPa in the supercritical region, more preferably below 20 MPa, and even more preferably below 10 MPa. However, a liquid phase is formed essentially above the saturated vapor pressure, and even if the pressure is increased above this level, the water density hardly changes, so an increase in solubility cannot be expected. Therefore, a pressure a few atmospheres higher than the saturated vapor pressure is sufficient to achieve adequate dissolution. Conversely, if the pressure of the aqueous material is too high, the cost of improving the pressure resistance of the manufacturing apparatus 1 will increase significantly, and the extraction unit 10 is also prone to deterioration, which is therefore undesirable.

[0101] There are no particular limitations on the types of heating devices for heating water-based materials. Examples of such heating devices include: heating devices that irradiate water-based materials with microwaves, and heating devices that heat water-based materials through heat conduction from a heating element such as a heater. By heating pressurized water-based materials, they can be brought to a subcritical state.

[0102] High-temperature steam can sometimes be used. Pressurized water can also be produced by adding this steam to a heat exchanger, or in conjunction with the aforementioned heating device. When clean, impurity-free heated steam at a temperature higher than the processing temperature is available, it can be directly introduced. By controlling the pressure with a pressure control valve to make the steam a liquid phase, heated water for extraction can be obtained.

[0103] Crystalline silica can be extracted from raw materials at temperatures above 70°C. Furthermore, the saturated vapor pressure of water at 70°C is approximately 0.03 MPa, at 100°C it is approximately 0.1 MPa, at 120°C it is approximately 0.2 MPa, and at 170°C it is approximately 0.8 MPa.

[0104] The temperature of the heated aqueous material should be above 70°C. If it is below 70°C, even if the raw material liquid comes into contact with the pressurized aqueous material, it may not be possible to fully dissolve or react and remove impurities such as crystalline silica or asbestos that may be present in the raw material, so it is not preferred.

[0105] In order to more effectively dissolve or react and remove impurities such as crystalline silica or asbestos that may be present in the raw materials, the temperature of the heated aqueous material is preferably above 100°C, more preferably above 120°C, and even more preferably above 150°C.

[0106] Furthermore, the temperature of the heated aqueous material is below 370°C, preferably below 300°C, more preferably below 250°C, and even more preferably below 200°C. If the temperature of the aqueous material is too high, the amount of hydroxyl groups on the surface of the raw material will decrease, which is therefore not preferred.

[0107] According to this embodiment, impurities such as crystalline silica or asbestos can be dissolved / reacted and removed using heat at a low temperature of 370°C or below (preferably 300°C or below, more preferably 250°C or below, even more preferably 200°C or below, and particularly preferably 150°C or below), thus offering a greater advantage in terms of manufacturing costs. The low-temperature heat can be considered not only from heat source devices but also from the reuse of waste heat within the factory.

[0108] [Contact between raw material solution and aqueous materials] A raw material liquid is introduced into the extraction unit 10, followed by a continuous supply of an aqueous material, thereby bringing the raw material liquid into contact with the aqueous material. The raw material liquid is instantly heated to a subcritical temperature by the heat retained by the aqueous material, initiating a reaction between the raw material liquid and the aqueous material. This reaction triggers the extraction or modification of any crystalline silica or asbestos that may be present in the raw material into the aqueous material.

[0109] The shape of the extraction unit 10 is not particularly limited as long as it can maintain the extraction conditions (i.e., subcritical state) of crystalline silica into the aqueous material for a specified time. Examples of the shape of the extraction unit 10 include: a spiral tube wound multiple times inside the heating cylinder, a molten salt bath jacket, a flowing sand bath, and other reactors covered by a constant temperature layer.

[0110] By shaping the extraction unit 10 into a spiral tube wound multiple times inside the heating cylinder or a reactor covered by a constant temperature layer, temperature changes and uneven temperatures in the mixture of raw material liquid and aqueous material caused by heat conduction through the device wall can be prevented, thereby enabling precise temperature control required for impurity extraction under subcritical conditions.

[0111] A high-temperature, high-pressure fluid containing impurities such as crystalline silica or asbestos dissolved in the extractor flows out from the outlet of the extractor unit 10. Because the solubility (solution concentration) is low, and the temperature and pressure are relatively low, these impurities can also be removed directly. After extraction, the extractor unit 10 contains a high-temperature, high-pressure fluid of hydrated magnesium silicate from natural minerals, with impurities removed.

[0112] From the viewpoint of properly removing impurities such as crystalline silica or asbestos, the hydrothermal reaction treatment time in the extraction unit 10 is preferably 1 minute or more, more preferably 5 minutes or more, and even more preferably 10 minutes or more.

[0113] On the other hand, from the viewpoint of production efficiency or to suppress the deterioration of the extraction unit 10, in order to reduce the effect of impurity crystal growth caused by Ostwald ripening, the hydrothermal reaction treatment time is preferably 10 hours or less, more preferably 5 hours or less, and even more preferably 2 hours or less.

[0114] [Cooling Unit 20] The cooling unit 20 is not mandatory. It can be configured as needed. Under relatively high temperature and pressure conditions, or when the dissolution concentration is high, cooling before the pressure control valve may cause damage due to the redeposition of dissolved impurities. In such cases, by installing the cooling unit 20, the dissolved impurities are redepositioned and removed, thereby reducing the load on the downstream pressure control valve.

[0115] Cooling is achieved by mixing the high-temperature, high-pressure fluid supplied from the extraction unit 10 with a low-temperature, high-pressure aqueous material that has been pressurized by a pressure pump or similar means. By mixing the high-temperature, high-pressure fluid with the low-temperature, high-pressure fluid, heat resulting from changes in fluid state—equivalent to the latent heat of vaporization—can be rapidly removed, ensuring safe and stable operation. Furthermore, if the high-temperature, high-pressure fluid is cooled below its critical temperature through this mixing, the rapid cooling of the fluid allows the reaction that generates the particles to stop almost instantaneously. Therefore, the particles generated are adjusted to a substantially uniform particle size.

[0116] This cooling method can be used when operating at low temperatures, but from an energy utilization perspective, heat recovery is sometimes required when operating at relatively high temperatures. In this case, cooling pipes are installed for indirect cooling, i.e., heat exchange, and the recovered heat is used to preheat the raw materials or circulating water.

[0117] Regarding particle recovery from the extraction tank, when powder is added to the container, it is recovered directly. When recovered in slurry form, the fluid containing the product particles is separated from the fluid by passing it through a filter. There are no particular limitations on the type of filter; for example, an inline filter can be listed. The filter can capture and remove impurities from hydrated magnesium silicate from natural minerals.

[0118] In semi-batch operation, the cooling operation of extraction unit 10 is not important because impurities are dissolved and removed. However, when the system is operated in batch mode, the dissolved impurities precipitate onto the silicate minerals used as the product through cooling. In this case, if the cooling rate is slow, crystalline components may sometimes redefine, thus making the cooling operation of the entire apparatus important.

[0119] <Silicate minerals> The average particle size of the silicate minerals obtained as products is preferably 100 nm or more. When the raw material is natural mineral, the silicate mineral is provided by crushing the natural mineral. Therefore, it is difficult to make the average particle size less than 100 nm. However, for products after hydrothermal reaction treatment, the average particle size also reaches 100 nm or more.

[0120] From the perspective of talc users' safety, the average particle size is preferably 200 nm or more, more preferably 500 nm or more, further preferably 1 μm or more, and especially preferably 5 μm or more.

[0121] Typically, when using natural talc minerals, they are often crushed and classified using sieves. In this case, the particle size further increases, reaching tens of μm or more. For even finer particles, gas-phase fractionation is used, which usually also results in particles around several μm. As a special case, sub-μm particles may also be recovered.

[0122] In this invention, the average particle size refers to the median diameter D50 determined by centrifugal sedimentation according to JIS R1619.

[0123] Furthermore, from the viewpoint of industrial production efficiency, the lower limit of the treatment concentration of silicate minerals is preferably 1% by weight or more, more preferably 3% by weight or more. The upper limit of the treatment concentration of silicate minerals is preferably 30% by weight or less, more preferably 20% by weight or less. From the viewpoint of being able to appropriately treat impurities (crystalline silica or asbestos) even when the concentration of impurities in the silicate minerals is relatively high, the upper limit of the treatment concentration of silicate minerals is further preferably 10% by weight or less, particularly preferably 5% by weight or less.

[0124] In addition, the content of crystalline silica in the silicate mineral obtained as the product is 0.1% by weight or less, preferably 0.08% by weight or less, more preferably 0.05% by weight or less, and even more preferably below the detection limit.

[0125] In addition, the asbestos content in the silicate mineral powder obtained as a product is 0.1% by weight or less, preferably 0.08% by weight or less, more preferably 0.05% by weight or less, and even more preferably below the detection limit.

[0126] In this embodiment, the contents of crystalline silica and asbestos are determined using an X-ray diffraction apparatus. The conditions of the X-ray diffraction apparatus are as follows.

[0127] Tube voltage: 45kV Tube current: 200mA For cathode: Cu Monochromaticization: Graphite Monochromator Detector: Scintillation Counter SC-70S Slit system: Light-receiving slit box 1 1.000mm Light-receiving slit box 2 1.125mm 1.000mm slit box for incident light Longitudinal slit limit 15mm Goniometer scanning speed: 0.10° per minute Full scale of the chromatogram: Determine the intensity of the diffraction lines and calculate the net peak area after subtracting the background. Select the diffraction lines on the recording chart as the appropriate full scale for confirming the chromatographic peak.

[0128] If the X-ray diffraction device is, for example, SmartLab 9MTP (manufactured by Rigaku Corporation), this condition can be set.

[0129] In crystalline silica, the quartz content was determined using a standard curve obtained from a standard quartz sample based on the peak intensity at a diffraction angle (2θ) of 26.6° in powder X-ray diffraction. Similarly, the cristobalite content was determined using a standard curve obtained from a standard cristobalite sample based on the peak intensity at a diffraction angle (2θ) of 22.0° in powder X-ray diffraction. Furthermore, the tridymite content was determined using standard curves obtained from a standard tridymite sample based on the peak intensities at diffraction angles (2θ) of 20.5° and 21.6° in powder X-ray diffraction.

[0130] The tremolite content in asbestos was determined using a standard curve obtained from a standard tremolite sample, based on the peak intensity at a diffraction angle (2θ) of 10.4° in powder X-ray diffraction. Similarly, the chrysotile content was determined using a standard curve obtained from a standard chrysotile sample, based on the peak intensities at diffraction angles (2θ) of 12.1° and 24.3° in powder X-ray diffraction.

[0131] Other methods were conducted in accordance with the Asbestos Analysis Manual [Version 1.20] based on prior investigations of the Asbestos Rules, in March 2016, under the Ministry of Health, Labour and Welfare, “8.4.3.1. Analytical Method for Asbestos Content in Talc”.

[0132] Typically, in the determination of trace components, the chromatographic peak is sometimes masked by baseline noise, requiring an extended integration time to improve the signal-to-noise ratio. Therefore, even without a powerful X-ray source, trace detection is theoretically possible using a standard XRD analysis apparatus. In the invention described in this embodiment, a long-term measurement is performed with this fully considered, and the results are analyzed using a standard curve based on a precise baseline evaluation. This allows for the dissolution and removal of crystalline silica or asbestos in aqueous materials, ensuring that the asbestos content truly reaches 0.1% by weight or less, as specified in Annex No. 0828001 of the Chemical Industry and Information Technology Department of Japan. Furthermore, based on the determination results obtained using a general-purpose X-ray diffraction apparatus, and employing precise analytical methods, it is confirmed with sufficiently high accuracy that the safety standards specified in that annex have been met.

[0133] In addition, whether the product is a silicate mineral powder is determined by the diffraction peaks in powder X-ray diffraction. For example, whether the product is hydrated magnesium silicate powder (talc powder) is determined by whether there are diffraction peaks at diffraction angles (2θ) of 9.45°, 18.97°, and 28.62° in the powder X-ray diffraction of the aforementioned precise analytical method.

[0134] In addition, the amount of NaOH aqueous solution (0.01M) required in the following method (Sears method) is preferably 180 μl or more, and more preferably 200 μl or more.

[0135] (1) Disperse 0.1g of silicate mineral powder in 10ml of water.

[0136] (2) After adding 2g of NaCl, adjust the pH to below 4 with dilute hydrochloric acid (0.12M).

[0137] (3) Add NaOH aqueous solution (0.01M) to make the pH 4, and then determine the amount of NaOH aqueous solution (0.01M) required from that point to pH 9.

[0138] Hydrothermal treatment of natural talc increases the amount of OH groups on its surface. Furthermore, the amount of OH groups increases with increasing hydrothermal temperature. The presence or absence of hydrothermal treatment also affects wettability. Hydrothermal treatment of natural talc reduces the contact angle, indicating improved wettability, i.e., increased hydrophilicity. Therefore, it can be said that hydrothermal treatment of silicate minerals improves their affinity with polar solvents used in cosmetics, thus enhancing their compatibility.

[0139] When the silicate mineral obtained according to the present invention is hydrated magnesium silicate powder, the hydrated magnesium silicate powder can be applied in the following fields: plastics (filler materials (improving rigidity, heat resistance, and dimensional stability), crystal nucleating agents), papermaking (fillers, resin control agents, coating agents), coatings (extender pigments (adjusting viscosity and gloss), powder coatings), electronic components (laminates, molded products, anti-corrosion inks, adhesives), ceramics (ceramic glazes, honeycomb ceramic raw materials), rubber (filler materials (improving heat resistance, reinforcement, etc.), mold release agents), cosmetics (foundation, body powder, baby powder, eyeshadow, lipstick), hygiene products (baby powder; prevention of prickly heat, rashes, etc.), pharmaceuticals (excipients for tablets, lubricants, slip agents adhering to medical rubber gloves), food (glue bases, manufacturing aids (anti-blocking)), and agriculture (anti-caking agents for fertilizers, pesticide carriers), etc. In particular, due to its high level of safety comparable to that of synthetic talc, the hydrated magnesium silicate powder obtained according to the present invention is preferably used in the fields of cosmetics, hygiene products, pharmaceuticals and / or food.

[0140] For example, when applied in the cosmetics field, the cosmetic composition may, in addition to the silicate minerals of the present invention, contain various exemplified ingredients such as colorants, extender pigments, brighteners, oily components, moisturizers, surfactants, thickeners, preservatives, ultraviolet scattering agents, antioxidants, and chelating agents, as needed.

[0141] Examples of colorants include, but are not limited to, inorganic pigments, organic pigments, dyes, and natural pigments.

[0142] Examples of extender pigments include, but are not limited to, inorganic powders such as silica, mica, synthetic fluorophlogopite, glass powder, barium sulfate, kaolin, bentonite, lithium saponite, zeolite, bismuth oxychloride, zirconium oxide, magnesium oxide, aluminum oxide, calcium sulfate, barium sulfate, magnesium sulfate, calcium carbonate, magnesium carbonate, and talc. Other examples include, but are not limited to, organic powders such as nylon, polyethylene, cross-linked polymers (vinyl dimethylsiloxane / polymethylsiloxane silsesquioxane), polymethyl methacrylate, lauroyl lysine, silk powder, cellulose powder, polyvalent metal salts of long-chain fatty acids, and various wax powders.

[0143] Examples of brightening agents include: materials made by coating the surface of plate-shaped powders such as mica, synthetic fluorophlogopite, glass, silica, and alumina with colorants such as titanium oxide, iron oxide, silica, ultramarine, chromium oxide, tin oxide, chromium hydroxide, gold, silver, carmine, red 202, and yellow 4; and materials made by cutting thin film substrates such as polyethylene terephthalate / polymethyl methacrylate laminated powder, polyethylene terephthalate / aluminum vapor-deposited powder, and polyethylene terephthalate / gold vapor-deposited laminated powder into arbitrary shapes, but not limited to these.

[0144] As an oily component, it can be made from hydrocarbon oils, ester oils, waxes, higher alcohols, and animal and vegetable oils. Examples of hydrocarbon oils include squalane, dodecane, tetradecane, and hexadecane; examples of ester oils include phytosterol macadamia fatty acid esters, octyl dodecyl myristate, triglycerides (caprylic / capric), stearate, methyl heptyl isostearate, hexyl laurate, isoamyl laurate, (caprylic / capric) cocoyl ester, isocetyl myristate, isostearate, etc.; examples of waxes include beeswax, wood wax, carnauba wax, rice bran wax, sunflower seed wax, candelilla wax, ceresin wax, and lignite wax; examples of higher alcohols (monohydrins with 6 or more carbon atoms) include... Examples include: cetyl alcohol, stearyl alcohol, isostearyl alcohol, lauryl alcohol, behenyl alcohol, etc.; as animal and vegetable oils, examples include: avocado oil, flaxseed oil, almond oil, olive oil, cocoa butter, sesame oil, wheat germ oil, safflower oil, jojoba oil, phytosterol macadamia fatty acid esters, shea butter, turtle oil, camellia oil, peach kernel oil, castor oil, grapeseed oil, macadamia oil, coconut oil, rosehip oil, soybean oil, egg yolk oil, hydrogenated castor oil, hydrogenated coconut oil, hydrogenated cocoa butter, hydrogenated turtle oil, hydrogenated mink oil, tallow, mink oil, lanolin, and oily components extracted from these ingredients, but not limited to these.

[0145] Examples of moisturizers include: polyols such as glycerin, 1,3-butanediol, propylene glycol, polyethylene glycol, and diglyceride trehalose; high molecular weight compounds such as sodium hyaluronate, heparin analogues, sodium chondroitin sulfate, collagen, elastin, keratin, chitin, and chitosan; amino acids such as glycine, aspartic acid, and arginine; natural moisturizing factors such as sodium lactate, urea, and sodium pyrrolidone carboxylate; lipids such as ceramides, cholesterol, and phospholipids; and plant extracts such as chamomile extract, witch hazel extract, tea extract, and perilla extract, but are not limited to these.

[0146] As surfactants, anionic surfactants, cationic surfactants, nonionic surfactants, and amphoteric surfactants can be used. Examples include: polyoxyethylene alkyl ethers selected from polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, monocetylated glyceryl ether, polyoxyethylene stearyl ether, polyoxyethylene oil-based ether, etc.; polyoxyethylene derivatives such as polyoxyethylene alkyl allyl ether, polyoxyethylene stilbene phenyl ether, polyoxyethylene hydrogenated castor oil, polyoxyethylene lanolin, etc.; and sorbitan monolaurate, sorbitan monooleate, sorbitan sesquioleate, sorbitan monostearate, etc. Sorbitol fatty acid esters; polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate, etc.; polyoxyethylene sorbitan tetraoleate, etc.; polyethylene glycol fatty acid esters such as polyethylene glycol monolaurate and polyethylene glycol monooleate; alkyl glycerol ethers such as isostearyl glycerol ether; glyceryl monosorbate, etc., and one or more of the following glycerol fatty acid esters: sorbitan monosorbate. Examples include: anionic surfactants selected from fatty acid monocarboxylate salts, polyoxyethylene alkyl ether acetates, alkyl sulfonyl carboxylate salts, α-olefin sulfonates, polyoxyethylene alkyl sulfates, alkyl phosphates, polyoxyethylene alkyl ether phosphates, stearoyl methyl taurine and their salts; and amphoteric surfactants selected from fatty acid amamidopropyl betaine, alkyl imidazolium betaine, alkyl dimethyl aminoacetic acid betaine, alkyl dimethyl sulfonyl betaine, alkyl dimethyl amine oxide, alkyl hydroxy sulfonyl betaine, etc., but not limited to these.

[0147] Examples of thickeners include, but are not limited to, guar gum, locust bean gum, carrageenan, xanthan gum, carboxymethyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, hydrophobic hydroxypropyl methyl cellulose, polyvinyl alcohol, polyvinylpyrrolidone, carbomer, acrylic acid / alkyl methacrylate copolymer, polyethylene glycol, bentonite, (hydroxyethyl acrylate / sodium acryloyl dimethyl taurate) copolymer, (ammonium acryloyl dimethyl taurate / vinylpyrrolidone) copolymer, etc.

[0148] Examples of preservatives include: benzoic acid, sodium benzoate, dehydroacetic acid, sodium dehydroacetate, isobutylparaben, isopropylparaben, butylparaben, ethylparaben, propylparaben, benzylparaben, methylparaben, phenoxyethanol, chlorobutanol, chlorhexidine, salicylic acid, benzalkonium chloride, cetrimonium bromide, acridine yellow, benzalkonium chloride, cresol, gluconic acid and its derivatives, povidone-iodine, potassium iodide, iodine, isopropyl methylphenol, triclocarban, triclosan, photosensitive agent 101, photosensitive agent 201, parabens, phenoxyethanol, 1,2-pentanediol, alkyl diaminoglycine hydrochloride, piroctone ketone ethanolamine salt, miconazole, etc., but are not limited to these.

[0149] Examples of UV absorbers include: p-aminobenzoic acid, glyceryl p-aminobenzoate, ethyl dihydroxypropyl p-aminobenzoate, octyl dimethyl p-aminobenzoate, p-dimethylaminobenzoate, diethylaminohydroxybenzoyl benzoate, methyl anthranilate, humosalidinyl ester, 2-ethylhexyl salicylate, triethanolamine salicylate, 2-ethylhexyl p-methoxycinnamic acid, and di-2-methoxycinnamic acid mono-2- Glyceryl ethylhexanoate, methyl 2,5-diisopropylcinnamate, methyl bis(trimethylsiloxy)silyl isoamyl trimethoxycinnamate, isopropyl p-methoxycinnamate, a mixture of isopropyl p-methoxycinnamate / diisopropylcinnamate, 2-ethoxyethyl p-methoxycinnamate, diethanolamine p-methoxycinnamate, 4-isopropyl dibenzoylmethane, 4-tert-butyl-4'-methoxydibenzoylmethane, 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine, 2,4-bis-[{4-(2-ethylhexyloxy)-2-hydroxy}-phenyl]-6-(4-methoxyphenyl)-1,3,5-triazine, 2,4-dihydroxy Benzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 4-(2-β-pyranoglycoloxy)propoxy-2-hydroxybenzophenone, 2-hydroxy-4-n-octyloxybenzophenone, 2-ethylhexyl dimethoxybenzyldioxazolidinyl propionate, octocrylene, sinoxalate, phenylbenzimidazole sulfonic acid, 1-(3,4-dimethoxyphenyl)-4,4-dimethyl-1,3-pentanedione, 3-(4-methylbenzyl)camphor, methylenebisbenzotriazolyltetramethylbutylphenol, etc., but not limited to these.

[0150] Examples of ultraviolet scattering agents include, but are not limited to, titanium oxide, zinc oxide, and cerium oxide.

[0151] Antioxidants include, but are not limited to, natural vitamin E, tocopherol, butylated hydroxytoluene, butylated hydroxyanisole, sorbic acid, sodium sulfite, ascorbic acid, isoascorbic acid, L-cysteine ​​hydrochloride, etc.

[0152] Examples of pH adjusters include: inorganic acids (hydrochloric acid, sulfuric acid, phosphoric acid, polyphosphoric acid, boric acid, etc.), organic acids (lactic acid, acetic acid, citric acid, sodium citrate, tartaric acid, malic acid, succinic acid, sodium succinate, oxalic acid, gluconic acid, fumaric acid, propionic acid, acetic acid, aspartic acid, ε-aminocaproic acid, glutamic acid, aminoethylsulfonic acid, etc.), gluconolactone, ammonium acetate, inorganic bases (sodium bicarbonate, sodium carbonate, potassium hydroxide, sodium hydroxide, calcium hydroxide, magnesium hydroxide, etc.), and organic bases (monoethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, lysine, etc.), but are not limited to these.

[0153] Examples of chelating agents include: ethylenediaminetetraacetic acid (EDTA), ethylenediaminetetraacetic acid salts (sodium salts such as sodium EDTA (Japanese Pharmacopoeia, EDTA-2Na, etc.), potassium salts, etc.), phytic acid, gluconic acid, polyphosphoric acid, metaphosphoric acid, etc., but not limited to these.

[0154] The aforementioned colorants and extender pigments can be used after surface treatment with a surface treatment agent as needed. As a surface treatment agent, for example, surface treatment can be performed using fluorine compound treatment, organosilicon treatment, organosilicon resin treatment, side chain treatment, silane coupling agent treatment, titanium coupling agent treatment, oil treatment, metal soap treatment, N-acylated lysine treatment, polyethylene glycol treatment, PVA treatment, polyacrylic acid treatment, hyaluronic acid treatment, alginate treatment, inorganic compound treatment, polyurethane crosslinking polymer treatment, plasma treatment, mechanochemical treatment, etc., but is not limited to these. Among these, metal soap treatment and polyurethane crosslinking polymer treatment are preferred. For metal soap treatment, aluminum dimyristate treatment, aluminum stearate treatment, and aluminum distearate treatment are preferred. For polyurethane crosslinking polymer treatment, (HDI / trimethylolhexyl lactone) crosslinking polymer treatment is preferred.

[0155] Furthermore, until now, the formation of underground minerals has been a precipitation process influenced by temperature and pressure, and the composition of the precipitates varies depending on the mining location. Detailed investigation and selection of fractions virtually free of the aforementioned impurities has been the only solution. However, according to the present invention, even raw materials containing impurities exceeding specified values ​​can have their impurity content reduced below the specified values. In this respect, the present invention offers a significant advantage to silicate mineral processing and sales companies.

[0156] In this invention, "product containing silicate minerals" means both cases where silicate minerals are included in a composition and cases where silicate minerals are attached to an article. For example, "pharmaceutical containing silicate minerals" means both cases where silicate mineral powder is included in a pharmaceutical composition as an excipient or lubricant for tablets and cases where silicate mineral powder is attached to a medical rubber glove.

[0157] Example The present invention will be specifically described below through embodiments, but the present invention is not limited to these embodiments.

[0158] Table 2

[0159] Table 3

[0160] <Experimental Example 1> Hydrothermal Reaction Treatment of Natural Talc Containing Quartz [Hydrothermal reaction treatment of natural talc] The experiment was conducted using an intermittent testing machine (device name: vibrating reactor heating and stirring device, manufactured by AKICO Co., Ltd.). In a 5 ml container made of Inconel nickel alloy, 0.45 g of natural talc (concentration: 10% by weight) with an average particle size of 5 μm and containing quartz as an impurity, and 4 ml of H₂O were added. After thorough mixing, the mixture was subjected to a hydrothermal reaction for 10 minutes under the conditions described in Table 2 using the intermittent testing machine. After cooling, the mixture was thoroughly washed with water to obtain processed talc.

[0161] [evaluate] Touching the processed talc after hydrothermal reaction treatment reveals the same smoothness as the natural talc before hydrothermal reaction treatment.

[0162] The average particle size was measured for the hydrothermal treated talc. The results showed that the average particle size was 5 μm in all examples.

[0163] In addition, powder X-ray diffraction was performed on natural talc before hydrothermal reaction treatment and on processed talc after hydrothermal reaction treatment. Figure 2 It is the result of natural talc before hydrothermal reaction treatment. Figure 3 This is the result of processing talc after hydrothermal reaction treatment in Examples 1-1. Additionally, Table 3 shows the changes in impurity content before and after hydrothermal reaction treatment in each example and comparative example. Figure 2 and Figure 3In powder X-ray diffraction, diffraction peaks were observed at diffraction angles (2θ) of 9.45°, 18.97°, and 28.62°. Therefore, this indicates that the substance after hydrothermal treatment is talc.

[0164] On the other hand, a chromatographic peak originating from quartz (crystalline silica) appeared near 2θ = 26.6° before the hydrothermal treatment. The standard curve obtained using a standard quartz sample showed that the talc before the hydrothermal treatment contained 0.11% by weight of quartz. Furthermore, no denaturation occurred after the hydrothermal treatment, and the chromatographic peak from quartz disappeared. Therefore, in Examples 1-1, it can be confirmed that quartz can be sufficiently removed.

[0165] Similarly, in Examples 1-2 to 1-13, it was confirmed that quartz could be sufficiently removed from natural talc. In particular, in Examples 1-10 to 1-13, it was confirmed that even natural talc with a relatively high impurity content could be sufficiently removed from it. Furthermore, in Examples 1-6 and 1-7, it was confirmed that even when the concentration of natural talc in the hydrothermal reaction treatment was set to a relatively high level, quartz could be sufficiently removed from it.

[0166] <Experimental Example 2> Hydrothermal Reaction Treatment of Natural Talc Containing Quartz (pH Dependence) The pH was adjusted to 1.4 (Example 2-1), 2.5 (Example 2-2), 6.4 (Example 2-3), and 12.0 (Comparative Example 2) during hydrothermal treatment using nitric acid and sodium hydroxide. Otherwise, processed talc was obtained by the same method as in Example 1-1.

[0167] Evaluation by XRD showed that the chromatographic peaks originating from quartz were reduced or disappeared in the products obtained after hydrothermal treatment at pH 1.4, 2.5, and 6.4. However, the chromatographic peaks originating from quartz remained in the products obtained after hydrothermal treatment at pH 12.0. Since the pH in Example 1-1 was 9.4, it was confirmed that quartz could be removed under conditions below this pH, while it could not be removed at excessively high pH levels.

[0168] It should be noted that for the products obtained at pH 1.4, 2.5 and 6.4, the average particle size of the particles was measured once and the result was 5 μm.

[0169] <Experimental Example 3> Hydrothermal reaction treatment of natural talc containing quartz (addition of Mg ions) 0.06 g of natural talc (concentration: 1.5 wt%), 3 mg of MgCl2 (concentration: 0.075 wt%), and 4 ml of H2O were added to an Inconel nickel alloy container. The hydrothermal reaction time was set to 240 minutes. Otherwise, processed talc was obtained by the same method as in Example 1-1.

[0170] The results of XRD evaluation confirmed a reduction in chromatographic peaks from quartz. Even with natural talc, which has a relatively high impurity content similar to that in Examples 1-5, the same amount of quartz was reduced at a hydrothermal reaction temperature of 150°C.

[0171] <Experimental Example 4> Hydrothermal Reaction Treatment of Natural Talc Containing Impurities Different from Quartz [Example 4-1] Hydrothermal reaction treatment of natural talc containing cristobalite As a raw material, natural talc containing 0.12% by weight of cristobalite, a type of crystalline silica, was used. Otherwise, processed talc was obtained by the same method as in Examples 1-1.

[0172] The XRD results showed that the chromatographic peak at a diffraction angle (2θ) of 22.0° from cristobalite disappeared, thus confirming that the content of cristobalite could be reduced to below 0.1% by weight through hydrothermal treatment.

[0173] [Example 4-2] Hydrothermal reaction treatment of natural talc containing tridymite As a raw material, natural talc containing 0.12% by weight of cristobalite, a type of crystalline silica, was used. Otherwise, processed talc was obtained by the same method as in Examples 1-1.

[0174] The XRD results showed that the chromatographic peaks at diffraction angles (2θ) of 20.5° and 21.6° from tricrite disappeared, thus confirming that hydrothermal treatment can reduce the content of tricrite to below 0.1% by weight.

[0175] [Examples 4-3 to 4-5] Hydrothermal reaction treatment of natural talc containing chrysotile asbestos Natural talc containing 0.15% by weight of chrysotile asbestos was used to perform hydrothermal treatment at 250°C for 10 minutes, 40 minutes, and 120 minutes. Otherwise, processed talc was obtained by the same method as in Examples 1-1.

[0176] The results of XRD evaluation showed that the chrysotile content was 0.075% by weight (processing time 10 minutes), 0.03% by weight (processing time 40 minutes), and below the detection limit (processing time 120 minutes), confirming that hydrothermal treatment can reduce the chrysotile content to below 0.1% by weight.

[0177] Generally, chrysotile asbestos is a stable substance, but under hydrothermal conditions, it dissolves more readily from the tips of needle-like minerals compared to ordinary minerals. However, even if it dissolves, talc dissolution may also occur; therefore, the dissolution rate, the ratio of dissolved amount to talc dissolved amount, and the amount remaining as a result are important. Considering the dissolution rate and amount of a large number of silicate minerals, even if the same amount is dissolved, only magnesium silicate may ultimately remain. These results demonstrate a significant dissolution and removal effect on chrysotile asbestos, showing that it is possible to remove asbestos components from talc.

[0178] <Experimental Example 5> Hydrothermal Reaction Treatment of Silicate Minerals Different from Natural Talc [Example 5-1] Hydrothermal reaction treatment of magnesium aluminum silicate containing quartz As a raw material, magnesium aluminum silicate containing 0.12% by weight of quartz was used, otherwise the processed mineral was obtained by the same method as in Examples 1-1.

[0179] The results of XRD evaluation showed a reduction in diffraction peaks from quartz, thus confirming that the quartz content could be reduced to 0.04% by weight through hydrothermal treatment.

[0180] [Example 5-2] Hydrothermal treatment of calcium silicate containing quartz As a raw material, calcium silicate containing 0.12% by weight of quartz was used, otherwise the processed mineral was obtained by the same method as in Examples 1-1.

[0181] The results of XRD evaluation showed a reduction in diffraction peaks from quartz, thus confirming that the quartz content could be reduced to 0.04% by weight through hydrothermal treatment.

[0182] [Examples 5-3 to 5-4] Hydrothermal reaction treatment of magnesium silicate containing quartz Magnesium silicate containing 0.12% by weight of quartz was used as the raw material. Otherwise, the processed minerals were obtained by the same method as in Examples 1-1 (processing times of 10 minutes and 40 minutes).

[0183] The XRD results showed that the diffraction peaks from quartz disappeared, thus confirming that hydrothermal treatment could reduce the quartz content to 0.01% by weight (10 minutes) and below the detection limit (120 minutes).

[0184] <Experimental Example 6> Relationship between hydrothermal treatment temperature and the amount of OH groups and wettability on the talc surface Table 4 The samples in each embodiment and comparative example, and the conditions of the hydrothermal reaction treatment.

[0185] Table 5

[0186] Except for the conditions described in Table 4, the processed minerals were obtained by the same method as in Examples 1-1.

[0187] [Amount of OH groups on the surface of talc] The Sears method was used to evaluate the amount of OH groups on the surface of talc. The specific steps are as follows.

[0188] (1) Disperse 0.1g of the processed mineral in 10ml of water. (2) Add 2g of NaCl and adjust the pH to below 4 with dilute hydrochloric acid (0.12M). (3) Add NaOH aqueous solution (0.01M), and after the pH reaches 4, determine the amount required from that point to reach pH 9.

[0189] The results are shown in Table 5. It can be confirmed that hydrothermal treatment of natural talc increases the amount of OH groups on the surface, and the amount of OH groups increases with increasing hydrothermal temperature.

[0190] [Wetting properties] For Examples 6-2 and Comparative Example 6, talc was uniformly loaded onto an X-ray diffraction sample holder. Then, a drop of water (10 μl) was added, and the contact angle was observed.

[0191] The results are shown in Table 5. It can be confirmed that the contact angle decreases slightly after hydrothermal treatment of natural talc. This means that the wettability is improved, i.e., the hydrophilicity is enhanced. Therefore, it can be said that hydrothermal treatment of silicate minerals improves their affinity with polar solvents used in cosmetics and enhances their compatibility.

[0192] <Experimental Example 7> Application in Color Cosmetics [Experimental Example 7-1] Application in Foundation Foundation powder was prepared according to the formulation shown in Table 6. In Example 7-1, the hydrothermally treated talc obtained in Example 1-1 was used as talc. In Comparative Example 7-1, natural talc before hydrothermal treatment in Example 1-1 was used as talc.

[0193] Table 6

[0194] (※) Example 7-1: Talc = Hydrothermally treated talc obtained in Example 1-1 Comparative Example 7-1: Talc = Natural talc before hydrothermal treatment in Example 1-1 For the obtained foundation, the slurry state, hardness, drop strength, and powder yield were evaluated. The results confirmed that the foundation using hydrothermally treated talc had the same quality as the foundation using untreated natural talc.

[0195] [Experimental Example 7-2] Application in loose powder The powder was prepared according to the formulation shown in Table 7. In Examples 7-2, the hydrothermally treated talc obtained in Example 7-1 was used as the talc. In Comparative Example 7-2, the natural talc before hydrothermal treatment in Example 1-1 was used as the talc.

[0196] Table 7

[0197] (※) Example 7-2: Talc = Hydrothermally treated talc obtained in Example 1-1 Comparative Example 7-2: Talc = Natural talc before hydrothermal treatment in Example 1-1 The obtained loose powder was evaluated for its slurry state, hardness, drop strength, and yield. The results confirmed that loose powder made from hydrothermally treated talc had the same quality as loose powder made from untreated natural talc.

[0198] [Experimental Example 7-3] Application in eyebrow pencils Two types of eyebrow pencils were prepared according to the formulations shown in Table 8. In Examples 7-3-1 and 7-3-2, the hydrothermally treated talc obtained in Example 1-1 was used as the talc. In Comparative Examples 7-3-1 and 7-3-2, the natural talc before undergoing the hydrothermal treatment in Example 1-1 was used as the talc.

[0199] Table 8

[0200] (※) Example 7-3-1: Talc = Hydrothermally treated talc obtained in Example 1-1 Prescription = Prescription recorded in Experimental Example 7-3-1 Example 7-3-2: Talc = Hydrothermally treated talc obtained in Example 1-1 Prescription = Prescription described in Experimental Example 7-3-2 Comparative Example 7-3-1: Talc = Natural talc before hydrothermal treatment in Example 1-1 Prescription = Prescription recorded in Experimental Example 7-3-1 Comparative Example 7-3-2: Talc = Natural talc before hydrothermal treatment in Example 1-1 Prescription = Prescription described in Experimental Example 7-3-2 The resulting eyebrow pencils were evaluated for their paste consistency and drop strength. The results confirmed that eyebrow pencils made with hydrothermally treated talc were of equivalent quality to those made with untreated natural talc.

[0201] <Experimental Example 8> Application in skincare and cosmetic products [Experimental Example 8-1] Application in Summer Body Lotion Summer body lotion was prepared according to the formulation shown in Table 9. In Example 8-1, the hydrothermally treated talc obtained in Example 1-1 was used as the talc. In Comparative Example 8-1, the natural talc before hydrothermal treatment in Example 1-1 was used as the talc.

[0202] Table 9

[0203] (※) Example 8-1: Talc = Hydrothermally treated talc obtained in Example 1-1 Comparative Example 8-1: Talc = Natural talc before hydrothermal treatment in Example 1-1 The slurry condition of the obtained summer body lotion was evaluated. The results confirmed that the summer body lotion using hydrothermally treated talc had the same quality as the summer body lotion using untreated natural talc.

[0204] [Experimental Example 8-2] Application in Pore-Covering Emulsions Pore-concealing emulsions were prepared according to the formulations shown in Table 10. In Examples 8-2, the hydrothermally treated talc obtained in Examples 1-1 was used as the talc. In Comparative Examples 8-2, natural talc before hydrothermal treatment in Examples 1-1 was used as the talc.

[0205] Table 10

[0206] (※) Example 8-2: Talc = Hydrothermally treated talc obtained in Example 1-1 Comparative Example 8-2: Talc = Natural talc before hydrothermal treatment in Example 1-1 The slurry condition of the obtained pore-covering emulsion was evaluated. The results confirmed that the pore-covering emulsion using hydrothermally treated talc had the same quality as the pore-covering emulsion using untreated natural talc.

[0207] [Experimental Example 8-3] Application in cleansing powder Cleansing powder was prepared according to the formulation shown in Table 11. In Examples 8-3, the hydrothermally treated talc obtained in Examples 1-1 was used as talc. In Comparative Examples 8-3, natural talc before hydrothermal treatment in Examples 1-1 was used as talc.

[0208] Table 11

[0209] (※) Example 8-3: Talc = Hydrothermally treated talc obtained in Example 1-1 Comparative Example 8-3: Talc = Natural talc before hydrothermal treatment in Example 1-1 The slurry condition of the obtained facial cleansing powder was evaluated. The results confirmed that facial cleansing powder made with hydrothermally treated talc had the same quality as facial cleansing powder made with untreated natural talc.

[0210] Explanation of icon numbers 1 Manufacturing apparatus 10 Extraction Units 20 Cooling Units.

Claims

1. A silicate mineral, wherein, The content of both crystalline silica and asbestos is less than 0.1% by weight.

2. The silicate mineral according to claim 1, wherein it contains carbonate.

3. The silicate mineral powder according to claim 1, wherein, The average particle size of primary particles is over 100 nm.

4. The silicate mineral powder according to claim 1, wherein, The following method requires a minimum of 180 μl of 0.01 M NaOH aqueous solution, and the method includes: (1) Disperse 0.1g of silicate mineral powder in 10ml of water. (2) After adding 2g of NaCl, adjust the pH to below 4 using 0.12M dilute hydrochloric acid. (3) Add 0.01M NaOH aqueous solution to make the pH 4, and then determine the amount of 0.01M NaOH aqueous solution required from that point to pH 9.

5. A cosmetic product containing any one of the silicate minerals according to claims 1 to 4.

6. A hygiene product comprising any one of claims 1 to 4 silicate minerals.

7. A pharmaceutical product comprising any one of the silicate minerals according to claims 1 to 4.

8. A food product containing any one of the silicate minerals according to claims 1 to 4.

9. A method for manufacturing silicate minerals, wherein, This includes processes such as treating silicate minerals derived from natural minerals with warm or hot water or hydrothermal reaction at a pH below 9.

4.

10. The method according to claim 9, wherein, The warm water or hot water treatment or the hydrothermal reaction treatment is carried out in the presence of carbonic acid or CO2.

11. The method according to claim 9, wherein, The warm water or hot water treatment or the hydrothermal reaction treatment is carried out in the presence of Mg ions.

12. The method according to claim 9, wherein, The temperature in the warm water or hot water treatment or the hydrothermal reaction treatment is above 70°C and below 370°C, and the pressure is above the saturated vapor pressure of water.

13. The method according to claim 9, wherein, The time for the warm water or hot water treatment or the hydrothermal reaction treatment is more than 1 minute.

14. The method according to claim 9, wherein, The warm water or hot water treatment or the hydrothermal reaction treatment is carried out using an intermittent or semi-intermittent device.

15. The method according to claim 14, wherein, The reaction device is the semi-batch device mentioned above. The amount of aqueous solvent supplied to the semi-intermittent device is at least 0.1 times the theoretical amount required to saturate the crystalline silica contained in the silicate minerals used as raw materials in the reaction solution containing coexisting ions in the reaction field.

16. The method of claim 14, wherein, The reaction device is the semi-batch device mentioned above. The amount of crystalline silica contained in the silicate minerals used as raw materials in the semi-intermittent apparatus is less than 10 times the theoretical amount required for saturation dissolution relative to the reaction solution containing coexisting ions in the reaction field.

17. The method according to claim 9, wherein, Using a flow-through device, the silicate minerals are supplied to water in a suspended state for the warm water treatment, the hot water treatment, or the hydrothermal reaction treatment.

18. The method according to claim 17, wherein, The concentration of the silicate mineral slurry supplied to the flow-through device is at least 0.1 times the theoretical amount required to saturate the crystalline silica contained in the silicate minerals used as raw materials in a reaction solution containing coexisting ions in the reaction field.

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