JP2016030708A - Calcium carbonate composite - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite consisting of spherocrystal calcite-type calcium carbonate and hydroxy-apatite.SOLUTION: A calcium carbonate composite 1 consists of a calcite-type calcium carbonate 2 having a spherocrystal structure and hydroxy-apatite layer 3 formed on the outer periphery of the calcite-type calcium carbonate. A production method of the calcium carbonate composite 1 includes: a carbonation step of adding carbon dioxide gas to an aqueous suspension of calcium hydroxide; and a dripping step of dripping phosphoric acid or a phosphate solution to a slurry solution of the calcite-type calcium carbonate 2 that is obtained in the carbonation step and has the spherocrystal structure. The hydroxy-apatite layer 3 is formed on the outer periphery of the calcite-type calcium carbonate 2 having the spherocrystal structure.EFFECT: The calcite-type calcium carbonate is high in slipperiness owing to the structure in which the hydroxy-apatite layer covers the calcite-type calcium carbonate having the spherocrystal structure and facilitates imparting dry and moist feelings when added to e.g. cosmetics.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a composition comprising calcite calcium carbonate having spherulites and hydroxyapatite among calcium carbonates.

  Calcium carbonate is an inorganic material widely used in industrial fields such as rubber, plastic, paper, and paint. Calcium carbonate includes heavy calcium carbonate obtained by physically pulverizing limestone and chemically produced light calcium carbonate. Light calcium carbonate that can control particle size and particle shape is reinforcing and white. Since it can be expected to have effects such as glitter, it is widely used industrially.

  For example, calcium carbonate has characteristics such as reinforcement, whiteness, and luster as described above, and is therefore used as an additive to rubber, plastic, paper, paint, and the like. When used as an additive in these industrial products, they can play a role of increasing the amount without adversely affecting the characteristics of the industrial product, enhancing whiteness, and increasing the luminance.

  Calcium carbonate is used as an additive for cosmetics due to the above-described whiteness. This is because the brightness (improving whiteness) of cosmetics used on the skin such as basic cosmetics and applied cosmetics can be realized.

  Under such circumstances, the spherical shape of light calcium carbonate has attracted attention because of its fluidity and light scattering properties. Spherical calcium carbonate usually has a vaterite crystal structure, and a method of introducing carbon dioxide gas by incorporating monoethanolamine into an aqueous suspension of calcium hydroxide (see, for example, Patent Document 1) By a manufacturing method disclosed in a method of adding a sulfonated polymer to water-soluble calcium (for example, see Patent Document 2), a method of adding a divalent cation to water-soluble calcium (for example, see Patent Document 3), etc. It has been proposed to have

  However, vaterite-type calcium carbonate has a problem that it easily changes to a calcite-type crystal structure by the presence of water or heat, and the spherical shape also collapses.

  In contrast, as described above, calcite-type calcium carbonate has a stable crystal form, and as a result, is stable in terms of physical properties and durability. In this stability, calcite-type calcium carbonate is superior to vaterite-type calcium carbonate, and can be optimally used for additives, extenders, and the like. On the other hand, when manufactured through a general manufacturing method, calcite-type calcium carbonate tends to have a cubic shape or a spindle shape. As a result, it is very difficult to obtain a calcite-type calcium carbonate having a spherical shape.

In such a situation, a technique for realizing a spherical calcite-type calcium carbonate has been proposed (see, for example, Patent Documents 4, 5, and 6).
However, as will be described later, the calcite-type calcium carbonate obtained by the techniques of Patent Documents 4, 5, and 6 has a problem in that it has problems in use for industrial products, cosmetics, beauty products, and the like.

  On the other hand, calcium carbonate has a problem that it is irritating to the skin and human body because it is weakly alkaline rather than neutral. For this reason, as described above, when calcium carbonate is used as an additive for industrial products, cosmetics, beauty products, etc., there is a problem that application applications are limited in order to avoid irritation. Or since calcium carbonate does not have a functional group on the surface, interaction with other substances such as hydrogen bonds cannot be expected. For this reason, it has the problem that it is inferior to adsorption performance and inferior to bioactivity.

  Under such circumstances, a technique of a composite that covers the surface of calcium carbonate with apatite has been proposed (see, for example, Patent Documents 7, 8, 9, and 10).

JP-A-1-301511 JP 62-91416 A JP-A-57-92520 JP-A 61-168524 Japanese Patent Laid-Open No. 7-33433 Japanese Patent Application Laid-Open No. 11-079740 Japanese Patent Laid-Open No. 07-118011 JP 09-081514 A JP 09-183617 A JP 2000-203815 A

  Patent Document 4 describes a spherical carbon solution by a method of introducing a carbon dioxide gas by adding a polyphosphate to an aqueous suspension of calcium hydroxide or a production method of introducing carbon dioxide gas to an aqueous suspension of calcium hydroxide. A technique for obtaining site-type calcium carbonate is disclosed.

  However, the calcite-type calcium carbonate obtained by Patent Document 4 has only a spherical outer shape of the resulting calcium carbonate, and the spherical shape does not necessarily have a spherulite (the predetermined point (one point). However, the present invention is not limited to a single point), so that a plurality of crystals do not necessarily form a polycrystalline body grown in a plurality of directions (preferably radially). For example, there may be a case where cubic or spindle-shaped fine particles are aggregated in a round shape and just look spherical. In the case of a sphere that does not have such a spherulite structure, stability as a spherical particle is poor, and naturally, durability and weakness are also produced. If the durability and strength are weak, when mixed as an additive or a bulking agent, it is deformed or destroyed, which adversely affects tactile sensation and durability.

  If it is just a spherical shape that is not a spherulite, it is inferior in strength (especially strength corresponding to external pressure) and durability, and even when added to industrial products, cosmetics, beauty products, etc. In the process (manufacturing process), the spherical calcium carbonate is deformed or destroyed. Alternatively, spherical calcium carbonate is deformed or destroyed at the stage of use (for example, it is applied to the skin if it is a cosmetic product).

  If such deformation or destruction occurs, the feeling of use becomes worse or the touch becomes worse. Of course, there is a problem that the whiteness and color developability level of calcium carbonate added as an additive is also lowered, and the purpose of addition cannot be sufficiently achieved.

  In addition, the technique disclosed in Patent Document 4 has a problem that the strength as a spherical particle is weak because it is spherical as a result of crystal growth from the center, but is spherical as an outer shape. ing. For the same reason, there is also a problem that the particle size of the spherical particles cannot be controlled and the particle size of the calcite-type calcium carbonate to be produced is dispersed.

  Patent Document 5 describes a solution obtained by adding a oxyacid salt of phosphorus or a polymer or copolymer salt of an unsaturated carboxylic acid to a solution in the middle of the reaction to cause a carbonation reaction, and an aqueous suspension of calcium hydroxide. Disclosed is a technique for producing spherical calcite-type calcium carbonate by a production method in which liquid b in the course of introduction of carbon dioxide gas is mixed (a + b) and further carbonated.

  Similarly to Patent Document 4, Patent Document 5 has various problems such as weak particle strength, difficulty in controlling the particle size, increased variation, and poor productivity.

  Patent Document 6 discloses a technique for producing spherical calcite-type calcium carbonate by a production method in which a suspension of primary particles obtained by introducing carbon dioxide gas into an aqueous suspension of calcium hydroxide is spray-dried. Is disclosed.

  Similarly to Patent Document 5, Patent Document 6 also has various problems such as weak particle strength, difficulty in controlling the particle size, increasing variation, and increasing the number of processes and poor productivity.

  The reason why the productivity is poor is that, in Patent Document 5, the manufacturing process is complicated. In Patent Document 5, the productivity of calcite-type calcium carbonate has deteriorated due to the large amount of labor and number of reaction steps in the production process. In patent document 6, since a large-scale apparatus such as a spraying apparatus such as a spray dryer is required, the production cost is high.

  Further, since the spherical particles have a spherical surface, they are slippery and may be easy to use when used as additives or extenders.

  As described above, all of Patent Documents 1 to 6 disclose the production of calcium carbonate and calcite-type calcium carbonate, but only calcium carbonate to the extent that the appearance is not spherulite and can be simply spherical can be achieved. . In addition to the problems of poor strength, particle size, uniformity, and productivity, there are problems that the purpose as an additive to industrial products, cosmetics, beauty products, etc. cannot be achieved.

  In addition, in the case of these additives consisting of calcium carbonate alone, since calcium carbonate is weakly alkaline rather than neutral, there is a problem that its application is limited due to problems such as irritation to the human body. Or there exists a problem in which the addition amount and addition method as an additive are restrict | limited. Furthermore, since calcium carbonate alone has no functional group on the surface, it cannot be expected to interact with other substances such as hydrogen bonds. For this reason, there exists a problem which is inferior to adsorption performance and inferior to bioactivity.

  Patent Document 7 discloses a composite in which the surface of light calcium carbonate is coated with apatite. By reacting the light calcium carbonate with a phosphoric acid aqueous solution, the surface of the light calcium carbonate is coated with apatite, and the purpose is to lower the pH.

  However, light calcium carbonate coated with apatite in the composite disclosed in Patent Document 7 is merely spherical in appearance as in Patent Documents 4 to 6 and has no spherulites. Since it does not have spherulites, even if it is a composite coated with apatite, it has problems such as strength, durability, uniform particle size, and poor productivity, as in Patent Documents 4-6. ing.

  If strength and durability are low, even if added to cosmetics or beauty products, the composite may be deformed or destroyed in the manufacturing process or use stage, and the objectives such as whiteness and high brightness cannot be achieved. In the case of destruction, the light calcium carbonate inside is exposed from the surface apatite, leading to the inability to solve the problem due to weak alkalinity.

  Further, in Patent Document 7, in order to uniformly form an apatite coating, it is necessary to react an aqueous phosphoric acid solution at 80 ° C. for 24 hours with spherical light calcium carbonate having a diameter of 7 μm. It is necessary to carry out a reaction for a very long time, resulting in poor productivity and problems such as cost and yield reliability.

  Patent Document 8 discloses a composite composed of plate-like or needle-like crystals of calcium carbonate and a calcium phosphate compound covering its outer surface. Patent Document 8 obtains the complex by reacting calcium carbonate having a diameter of 0.1 μm to 100 μm with an aqueous phosphoric acid solution at a Ca / P ratio of 1.5 to 3.5.

  However, the composite in Patent Document 8 is premised on a shell shape or heavy calcium carbonate. For this reason, shapes vary, and there is a problem that the feeling of use in added industrial products, cosmetics, beauty products, etc. is poor due to the lack of smoothness of the shapes. As a result, not only the manufacturing effort and the manufacturing cost but also the problem that the field of application as an additive is limited or its effect is difficult to occur.

  Patent Document 9 discloses a porous calcium carbonate compound for cosmetics which is a reaction product of calcium carbonate and a phosphoric acid compound and satisfies the following conditions.

(A) 0.5 ≦ Dx ≦ 20 (μm) (b) 1 ≦ α ≦ 3
(C) 0 ≦ β ≦ 3 (d) 50 ≦ Sw ≦ 300 (m ² / g)
(E) 50 ≦ x ≦ 300 (f) 50 ≦ y ≦ 300
dx: average particle diameter measured from SEM
α: Dispersion coefficient α = d50 / dx
d50: Average particle diameter measured by a particle size distribution meter
β: (d90−d10) / d50
d90: 90% diameter measured by particle size distribution meter d10: 10% diameter measured by particle size distribution meter Sw: BET specific surface area
x: Oil absorption y: Water absorption Tm2: 200 ° C of the composite Tm2: 200 ° C of the carrier

  However, Patent Document 9 also presupposes calcium carbonate that is not spherulite, as in Patent Documents 7 and 8. For this reason, even if the coating with apatite occurs under these conditions, there are the same problems of strength, shape, and feeling of use as in Patent Documents 7 and 8. Even when added to cosmetics, the feeling of use is poor, and in addition to the poor feeling of use, the merits of whiteness and brightness cannot be fully exhibited.

  In Patent Document 10, a calcium phosphate-based carrier is prepared from a 0.1 μm calcium carbonate slurry with a phosphoric acid aqueous solution. A calcium carbonate slurry and a phosphoric acid aqueous solution are separately dropped onto this carrier to obtain a composite.

  However, also in Patent Document 10, the calcium carbonate coated as in other documents is not spherulite. The shape may be a sphere or another shape, and a constant shape cannot be maintained. As a result, there are problems inferior in strength, durability, feeling of use and the like.

  Further, the composite of Patent Document 10 has a problem that the BET specific surface area is small. If the BET specific surface area is small, the porosity is weak and the strength and durability are also poor. In addition, the degree of whiteness is inferior, and the achievement of the purpose of adding to cosmetics and beauty products is weak.

  As described above, the calcium carbonate of the composite covered with the apatite of the prior art is not a spherulite (or it is not a sphere or a uniform shape), so that strength, durability, production There is a bad problem. Due to these problems, there has been a problem that even when added to industrial products, cosmetics, beauty products, etc., whiteness, brightness, gloss, etc. cannot be sufficiently improved. Or there was a problem that addition application to these products was difficult.

  An object of this invention is to provide the composite_body | complex which consists of calcite type | mold calcium carbonate and a hydroxyapatite which are spherulites in view of the said subject.

In view of the above problems, the calcium carbonate composite of the present invention includes a calcite-type calcium carbonate having a spherulite structure,
And a hydroxyapatite layer formed on the outer periphery of the calcite-type calcium carbonate.

  The composite of the present invention has a spherulite structure, which is a polycrystalline body in which a large number of crystals grow radially from a certain point by producing them under predetermined conditions, so that the outer shape is spherical or approximate to a sphere. However, it has sufficient strength. Of course, since it has a spherical shape or a shape close to a spherical shape, it is optimal as an additive to an article whose gloss is to be suppressed or as a bulking agent for a material to be increased.

  In particular, the calcite-type calcium carbonate with spherulites is used as an additive or extender to achieve the purpose of luster suppression and increase in weight, while maintaining the durability and strength of the added article or material. Will not be adversely affected.

  In addition, the invention makes it easy to control the particle size of the spherulite calcite-type calcium carbonate to be produced, and variations in particle size can be suppressed.

  The outer periphery of calcite-type calcium carbonate, which is such a spherulite, has a hydroxyapatite layer, so that it can be close to neutrality, weakening irritation to the living body, cosmetics and beauty products, etc. Addition application to products used directly in living bodies is also facilitated.

It is a schematic diagram of the calcium carbonate composite in Embodiment 1 of this invention. It is an electron micrograph of the calcite type | mold calcium carbonate 2 used as the foundation of the calcium carbonate complex 1 in Embodiment 1 of this invention. It is an electron micrograph of the calcite type calcium carbonate in Embodiment 1 of this invention. It is an electron micrograph which shows the calcium carbonate complex manufactured in this way. It is a manufacturing process flowchart which shows the manufacturing process of the calcium carbonate complex in Embodiment 1 of this invention. It is a polarizing microscope photograph of the calcite type | mold calcium carbonate of Example 1 shown by FIG. 2 is an electron micrograph of a fracture surface of calcite-type calcium carbonate obtained in Example 1. FIG. FIG. 8 is a polarization micrograph of FIG. 7. 2 is an electron micrograph of calcium carbonate of Comparative Example 1 described in Table 1. 2 is an electron micrograph of calcium carbonate of Example 2 described in Table 1. It is an electron micrograph of the calcium carbonate of Example 3 described in Table 1. It is an electron micrograph of the calcium carbonate of Example 4 described in Table 1. It is an electron micrograph of the calcium carbonate of Example 5 described in Table 1. 2 is an electron micrograph of calcium carbonate of Comparative Example 2 described in Table 1. 4 is an electron micrograph of calcium carbonate obtained in Example 6. 2 is an electron micrograph of calcium carbonate obtained in Example 7. 2 is an electron micrograph of calcium carbonate obtained in Example 8. 2 is an electron micrograph of calcium carbonate obtained in Example 9. 4 is an electron micrograph obtained in Comparative Example 3. 4 is an electron micrograph of calcium carbonate obtained in Comparative Example 4. 2 is an electron micrograph of calcium carbonate obtained in Example 10. 2 is an electron micrograph of calcium carbonate obtained in Example 11. It is an electron micrograph of calcium carbonate obtained in Example 12. 6 is an electron micrograph obtained in Comparative Example 5. 7 is an electron micrograph of calcium carbonate obtained in Comparative Example 6. 2 is an electron micrograph of calcium carbonate obtained in Example 13. 2 is an electron micrograph of calcium carbonate obtained in Example 14. 2 is an electron micrograph of calcium carbonate obtained in Example 15. It is an electron micrograph of a calcium carbonate composite in which a hydroxyapatite layer is not formed (the above production conditions 1 to 3 are not satisfied). 4 is an electron micrograph of a calcium carbonate composite having a granular hydroxyapatite layer produced under the production conditions 2 and 3. FIG. It is an electron micrograph of the calcium carbonate composite which satisfy | fills manufacturing conditions 1 and 3 and has a scaly hydroxyapatite layer. It is an electron micrograph of the aggregate of a calcium carbonate complex.

  The calcium carbonate composite according to the first aspect of the present invention comprises a calcite type calcium carbonate having a spherulite structure and a hydroxyapatite layer formed on the outer periphery of the calcite type calcium carbonate.

  With this configuration, when the strength and durability are high due to the spherulite structure, a synergistic effect of providing an outer layer of a hydroxyapatite layer that is neutral and less irritating occurs in calcite-type calcium carbonate. As a result, it can be optimally used as an additive in various compositions.

  In the calcium carbonate composite according to the second invention of the present invention, in addition to the first invention, the calcite-type calcium carbonate having a spherulite structure is a carbonic acid in which carbon dioxide gas is added to a calcium hydroxide aqueous suspension. Each of the plurality of crystals is a polycrystalline body grown in a plurality of directions from a single position or a plurality of positions.

  With this configuration, a polycrystal of calcite-type calcium carbonate grown from a predetermined position can be obtained.

  In the calcium carbonate composite according to the third invention of the present invention, in addition to the second invention, the process control temperature in the carbonation process in which carbon dioxide gas is added to the calcium hydroxide aqueous suspension is 18 ° C. ~ 65 ° C.

  With this configuration, the obtained calcite-type calcium carbonate has spherulites.

  In the calcium carbonate composite according to the fourth invention of the present invention, in addition to the second invention, in the carbonation step, when the carbonation rate of the calcium hydroxide aqueous suspension is less than 10%, the process control temperature is 20 ° C to 55 ° C, more preferably 25 ° C to 35 ° C.

  With this configuration, the obtained calcite-type calcium carbonate has a spherulite and has a uniform outer shape and particle size.

  In the calcium carbonate composite according to the fifth aspect of the present invention, in addition to the third or fourth aspect, in the carbonation step, when the carbonation rate of the calcium hydroxide aqueous suspension is 10% or more, the step The management temperature is 20 ° C to 60 ° C, more preferably 20 ° C to 40 ° C.

  With this configuration, the obtained calcite-type calcium carbonate has a spherulite and has a uniform outer shape and particle size. In particular, the outer shape tends to be substantially spherical.

  In the calcium carbonate complex according to the sixth invention of the present invention, in addition to any of the third to fifth inventions, in the carbonation step, the reaction rate of the carbonation rate of 1 to 5% is 2 mol% / The reaction rate when the carbonation rate is 5 to 10% is 0.16 mol% / min to 0.24 mol% / min, and the reaction rate after the carbonation rate is 10% or less is 1.1 mol / min or less.

  With this configuration, the obtained calcite-type calcium carbonate has spherulites, has a uniform outer shape and particle size, and has an advantage that the average particle size can be arbitrarily controlled.

  In the calcium carbonate composite according to the seventh invention of the present invention, in addition to any of the second to sixth inventions, the condensed phosphoric acid or its phosphoric acid may be added before or during the carbonation step. When the alkali metal salt is in the range of 0.03% to 1.5% by weight of phosphorus contained in the condensed phosphoric acid or the alkali metal salt with respect to the calcium hydroxide in the calcium hydroxide aqueous suspension. In order to be in the range, the production is further performed by further including a step of adding one or more times.

  With this configuration, the obtained calcite-type calcium carbonate has spherulites and has the merit that the outer shape and the uniform particle size are improved. Also, the outer shape tends to be substantially spherical.

  In the calcium carbonate composite according to the eighth aspect of the present invention, in addition to any of the second to seventh aspects, each of the plurality of crystals grows radially from one position to substantially the same length. It becomes a crystal and has a substantially spherical shape on the outer shape.

  With this configuration, the calcium carbonate composite becomes spherulite and has a substantially spherical outer shape, and is easily mixed with various articles.

  In the calcium carbonate composite according to the ninth aspect of the present invention, in addition to any of the first to eighth aspects, a calcite-type calcium carbonate slurry solution having a spherulite structure obtained after the carbonation step In addition, a hydroxyapatite layer is formed in a dropping step in which phosphoric acid or a phosphate solution is dropped.

  With this configuration, a hydroxyapatite layer is formed on the outer periphery of the spherulite calcite-type calcium carbonate.

  In the calcium carbonate composite according to the tenth aspect of the present invention, in addition to the ninth aspect, the solution temperature of the slurry solution is controlled to 50 ° C. to 80 ° C. in the dropping step.

  With this configuration, the formed hydroxyapatite layer tends to have a scale shape. By being scale-like, it is easy to contain an oil component, and when a calcium carbonate complex is added to cosmetics, makeup collapse is reduced.

  In the calcium carbonate composite according to the eleventh aspect of the present invention, in addition to the ninth aspect, the solution temperature of the slurry solution is controlled to 10 ° C. to 50 ° C. or 80 ° C. to 100 ° C. in the dropping step.

  With this configuration, the formed hydroxyapatite layer tends to have granularity. By being granular, slipperiness is increased, and when a calcium carbonate complex is added to cosmetics, a feeling of smoothness can be obtained while being smooth.

  In the calcium carbonate composite according to the twelfth aspect of the present invention, in addition to any of the ninth to eleventh aspects, the Ca / P which is the molar ratio of calcite-type calcium carbonate to phosphorus is 1.8. ~ 100.

  With this configuration, the hydroxyapatite layer is reliably formed.

  In the calcium carbonate composite according to the thirteenth aspect of the present invention, in addition to any one of the first to twelfth aspects, the hydroxyapatite layer has a scaly shape.

  By this structure, it is a scale-like, it is easy to contain an oil component, and when a calcium carbonate composite is added to cosmetics, makeup collapse decreases.

  In the calcium carbonate composite according to the fourteenth aspect of the present invention, in addition to any one of the first to twelfth aspects, the hydroxyapatite layer has a granular shape.

  Due to this configuration, the granularity increases the slipperiness, and when the calcium carbonate complex is added to cosmetics or the like, it is easy to produce a smooth and moist feeling.

  (Embodiment 1)

  Embodiment 1 will be described.

(Overview of the substance)
First, the outline | summary of the calcium carbonate complex in Embodiment 1 is demonstrated. FIG. 1 is a schematic diagram of a calcium carbonate complex according to Embodiment 1 of the present invention. In order to understand the structure, the inside can be seen through.

  As shown in FIG. 1, the calcium carbonate complex 1 in Embodiment 1 is formed on the outer periphery of a calcite type calcium carbonate 2 having a spherulite structure and a calcite type calcium carbonate 2 having this spherulite structure. Hydroxyapatite layer 3. As shown in FIG. 1, the hydroxyapatite layer 3 covers a calcite-type calcium carbonate 2 having a spherulite structure. Unlike the prior art, the object covered by the hydroxyapatite layer 3 is different in that it has a spherulite structure and calcite-type calcium carbonate having a spherulite structure.

(Calcite-type calcium carbonate with spherulite structure)
Here, the spherulite is defined as “a polycrystalline body in which a large number of crystals are grown in a plurality of directions (particularly in a radial manner) from a certain point (not strictly limited to a single point)”.

  The calcite-type calcium carbonate 2 that is the basis of the calcium carbonate composite in Embodiment 1 is formed of a polycrystalline body obtained by growing each of a plurality of crystals in a plurality of directions from a single or a plurality of positions. By being a polycrystalline body (spherulite as described above) in which each of a plurality of crystals grows in a plurality of directions from a single position or a plurality of positions, it has a structure excellent in strength and durability.

  Each of the plurality of crystals grows in a plurality of directions from a single position (that is, one point), so that each of the plurality of crystals to be grown (here, each of the plurality of crystals is usually a single crystal). ) Grows so as to spread from one point, so that the outer shape of the calcite-type calcium carbonate 2 obtained in addition to the stabilization of the bulk polycrystalline body shows a certain shape.

  In particular, when each of a plurality of crystals grows radially from a certain point, the calcite-type calcium carbonate 2 is a spherulite. In particular, at this time, each of the plurality of crystals grows to have substantially the same length, so that the calcite-type calcium carbonate 2 has a spherulite and has a substantially spherical outer shape. That is, when the outer shape is substantially spherical, it can be easily mixed with various materials as a filler, and having a spherulite has sufficient strength and durability.

  Conversely, when each of the plurality of crystals grows in a plurality of different directions other than the radial direction or grows with non-identical lengths, the calcite type calcium carbonate 2 has a non-spherical outer shape. For example, it may have a spindle shape or a substantially square shape.

  Here, each of the plurality of crystals is basically a single crystal, but is not limited to being strictly a single crystal.

  The calcite-type calcium carbonate 2 of the calcium carbonate complex 1 of Embodiment 1 is manufactured in a manufacturing process that includes a carbonation process in which carbon dioxide gas is added to a calcium hydroxide aqueous suspension. By this carbonation step, each of the plurality of crystals grows in a plurality of directions from a predetermined position to form a polycrystalline body. This polycrystal is calcite-type calcium carbonate 2.

  Further, not only a polycrystal but also a composite is included as an example of calcite-type calcium carbonate in Embodiment 1. A composite refers to a material in which two or more phases come into contact and become a bulk. The calcite type calcium carbonate 2 in Embodiment 1 is obtained in a production process including a carbonation process in which carbon dioxide gas is added to a calcium hydroxide aqueous suspension. For this reason, many calcite type calcium carbonate 2 is produced | generated in the calcium hydroxide aqueous suspension used as a raw material.

  FIG. 2 is an electron micrograph of calcite-type calcium carbonate 2 which is the basis of calcium carbonate complex 1 in Embodiment 1 of the present invention. As is clear from the photograph in FIG. 2, in the calcite-type calcium carbonate 2, each of a plurality of crystals grows in a plurality of directions from a certain predetermined position. A polycrystal obtained by a collection of a plurality of crystals growing in a plurality of directions or a complex thereof is calcite-type calcium carbonate 2 produced in a production process including the carbonation process in part.

  Here, spherulites are not synonymous with spheres. The spherical shape only needs to have a spherical outer shape regardless of the internal structure of the polycrystalline body. For example, even if the microcrystals that are the primary particles are simply assembled in a round shape, it becomes spherical.

  In this way, regardless of the internal structure, when it is only spherical in shape (appearance), its strength and durability are weak, and the obtained substance (calcium carbonate, etc.) is mixed with other substances. When it is used, the problem that the spherical shape cannot be maintained is generated. If the spherical shape cannot be maintained, naturally various problems occur.

  In contrast, in the calcite-type calcium carbonate 2 having a spherulite structure, a plurality of crystals grow in a plurality of directions from a predetermined position as shown in the photograph of FIG. At this time, if the growth direction of the plurality of crystals 1 is radial, the outer shape of the obtained calcite-type calcium carbonate is close to a substantially spherical shape or a substantially elliptical sphere. In particular, if it is radial and each of the plurality of crystals grows with substantially the same length, it has a spherical outer shape.

  At this time, even if it has a spherical shape or an elliptical sphere shape, the basis for forming this is a spherulite (each of a plurality of crystals grows in a plurality of directions from a predetermined position), so that the bulk density is High, excellent in strength and durability. For this reason, the calcite-type calcium carbonate 2 that is the basis of the calcium carbonate composite 1 in Embodiment 1 solves the problem of the simple spherical calcium carbonate on the outer shape in the prior art.

  Here, for spherulites, the meanings of spherulites in calcite-type calcium carbonate are described in “Journal of Crystal Growth 193 (1998) 374-381” and “Journal of Crystal Growth 193 (1998) 382-388”. Is described. As described above, this document discloses that a spherulite is a polycrystal obtained by growing a plurality of crystals in a plurality of directions from a certain position.

  Further, a substance having a spherulite shows a mode in which a light-emitting portion is generated in a unique circular shape when a photograph is taken with a polarizing microscope (for example, FIG. 7B of Japanese Patent Application Laid-Open No. 2010-151679). On the other hand, when a photograph of a simple spherical substance is taken with a polarizing microscope, such a mode is not shown, but only a mode as a circular variation is shown. Thus, as is clear from this document, mere spheres and spherulites have different physical properties.

  The calcite-type calcium carbonate that has become spherulites has the shape shown in FIG. FIG. 3 is an electron micrograph of calcite-type calcium carbonate in Embodiment 1 of the present invention. Unlike the photograph of FIG. 2, the entire outer shape as a spherulite is a sphere. The calcite-type calcium carbonate 2 which is a spherulite has such a shape.

(Hydroxyapatite layer)
As shown in FIG. 1, in the calcium carbonate composite 1 in Embodiment 1, the hydroxyapatite layer 3 is an outer layer that covers the outer periphery of the calcite-type calcium carbonate 2 that is a spherulite. The hydroxyapatite layer 3 covers the outer periphery of the calcite-type calcium carbonate 2 so that the calcium carbonate composite 1 becomes neutral. It is neutral and less irritating.

  Further, the hydroxyapatite layer 3 is bioactive, and also in this respect, the hydroxyapatite layer 3 has good affinity with the human body (surface or internal penetration), and is excellent in application to the human body. For example, even when the calcium carbonate composite 1 of the first embodiment is mixed in various fields of application such as cosmetics, skin creams, and skin coating agents that may be applied to the living body, it can be applied to the human body. There are few adverse effects.

  In addition, the hydroxyapatite layer 3 has a functional group of a hydroxyl group on the surface thereof, and also has a characteristic of high organic substance adsorption ability. Due to this characteristic, even if it is used for the human body or used for other purposes, the affinity for the object to be used is increased by increasing the adsorption ability of organic matter. Has merit.

  The hydroxyapatite layer 3 covers the outer periphery of the calcite-type calcium carbonate 2 that is a spherulite. At this time, the whole may be covered or a part may be insufficient. Strictly and physically, it does not require that the whole is covered, but may be in a state where it can be grasped that the whole is covered.

  Hydroxyapatite layer 3 is formed by adding phosphoric acid to a slurry solution of calcite-type calcium carbonate 2 having a spherulite structure obtained after the above-mentioned carbonation step, which is a step of producing spherulite calcite-type calcium carbonate 2. Or it forms by the dripping process in which a phosphate solution is dripped. By this dropping step, a calcium carbonate composite in which the hydroxyapatite layer 3 is formed on the outer periphery of the calcite-type calcium carbonate 2 having a spherulite structure as shown in FIG. 1 is manufactured.

  FIG. 4 is an electron micrograph showing the calcium carbonate composite produced as described above. As can be seen from the photograph in FIG. 4, the calcium carbonate composite 1 whose outer periphery is covered with hydroxyapatite is manufactured.

(Manufacturing process of calcium carbonate composite)
FIG. 5 is a manufacturing process flow chart showing the manufacturing process of the calcium carbonate composite according to Embodiment 1 of the present invention. The parts considered necessary for the explanation are selected and displayed.

  First, the collected limestone is prepared. The limestone is baked into quick lime. At this time, carbon dioxide gas is generated. This firing is a firing step. If quick lime is obtained through a baking process, water will be added to this quick lime and a digestion process will be performed. By this digestion process, quick lime becomes what is called slaked lime. This slaked lime is a calcium hydroxide aqueous suspension.

  A carbonation step of adding carbon dioxide gas to the calcium hydroxide aqueous suspension is performed. By the carbonation step, the spherulites shown in FIGS. 2 and 3 grow inside the calcium hydroxide aqueous suspension, and calcite-type calcium carbonate 2 having a spherulite structure is produced. In order to form a composite, phosphoric acid or a phosphate solution is dropped into the slurry in a state where calcite-type calcium carbonate having a spherulite structure is firmly formed and reacted as described below. By this reaction, a hydroxyapatite layer that does not peel off from the surface of the calcite-type calcium carbonate is formed.

  That is, a slurry solution is generated after the carbonation step.

  A dropping step in which phosphoric acid or a phosphate solution is dropped into the slurry solution is performed. By this dropping step, a hydroxyapatite layer 3 is formed on the outer periphery of the spherulite-structured calcite-type calcium carbonate 2 produced in the slurry solution. By forming this hydroxyapatite layer, the desired calcium carbonate composite 1 can be produced.

  As described above, the calcium carbonate composite 1 produced in this way has the advantage of having neutrality and low irritation and having a functional group of a hydroxyl group, and is added to various substances. To produce a composition. For example, the composition produced by addition is at least one of a pigment, a cosmetic, a beauty agent, a dentifrice, a paint, an abrasive and a polishing aid. Even when added to these, there is an effect that there is little irritation to the human body or the like, or the affinity to the application object is high.

  (Embodiment 2)

  Next, a second embodiment will be described. In the second embodiment, the efficiency in the production of calcite-type calcium carbonate 2 having a spherulite structure and the formation of the hydroxyapatite layer 3 will be described.

  First, the production of Example 1 using calcite-type calcium carbonate 2 will be described.

Example 1
Example 1 which is an actual manufacturing example and its result will be described. Example 1 is an example included in the scope of the present invention.

  In Example 1, 120 g of quicklime is added to 800 ml of tap water in a beaker at a stretch and digested, and then a calcium hydroxide aqueous suspension from which the residue is removed with a sieve is obtained. Subsequently, the calcium hydroxide concentration of this calcium hydroxide aqueous suspension is adjusted to 12% by weight, and an amount of 800 ml is taken out. Further, 1 wt% sodium hexametaphosphate (0.3 wt% in terms of phosphorus) is added to this 800 ml calcium hydroxide aqueous suspension with respect to calcium hydroxide. This calcium hydroxide aqueous suspension in the added state is used as a reaction initiation liquid.

  After maintaining the reaction initiation liquid at 30 ° C., 20 Vol% carbon dioxide gas is blown at a rate of 300 ml / min, and the carbonation step is performed while stirring. When the carbonation rate is 10%, the blowing rate of carbon dioxide gas is increased to 1500 ml / min. The temperature in this carbonation step is controlled within 30 ° C. ± 1 ° C. The reaction rate by this treatment is 0.2 mol% / min from the start of the reaction to the carbonation rate of 10%, and 0.8 mol% / min after the carbonation rate of 10%.

  The reacted solution obtained by the production procedure of Example 1 is filtered, washed with alcohol, and dried at 120 ° C. for 16 hours. As a result, 110 g of calcite-type calcium carbonate powder is obtained.

  FIG. 3 is an electron micrograph of the calcite-type calcium carbonate of Example 1 as described in Embodiment 1. As apparent from the photograph of FIG. 3, the outer shape of the obtained calcite-type calcium carbonate of Example 1 is substantially spherical. Moreover, it turns out that the particle size is 10 micrometers on average. FIG. 6 is a polarization micrograph of the calcite-type calcium carbonate of Example 1 shown in FIG. As is apparent from the photograph of FIG. 6, an embodiment in which a light emitting portion is generated in a unique circle, as illustrated in FIG. 7B of JP2010-151679 A, is shown.

  As is apparent from this polarized light micrograph, it is confirmed that the calcite type calcium carbonate obtained in Example 1 is a spherulite by having a unique circular light emitting portion. That is, the calcite type calcium carbonate of Embodiment 1 of the present invention is a spherulite. In the calcite-type calcium carbonate obtained in Example 1, each of a plurality of crystals constituting the spherulite grows radially from one position to have substantially the same length. As a result, the outer shape is substantially spherical. The almost spherical shape is optimal for use as various fillers.

  FIG. 7 is an electron micrograph of a fracture surface of calcite-type calcium carbonate obtained in Example 1. FIG. 7 shows the inside of FIG. As can be seen from the electron micrograph of FIG. 7, a plurality of crystals grow in a plurality of directions. Further, it can be seen that the crystal grows in a plurality of directions and at the same time in a radial pattern and substantially the same length. Also from the photograph of FIG. 7, it is confirmed that the calcite type calcium carbonate obtained in Example 1 has spherulites. FIG. 8 is a polarization micrograph of FIG. FIG. 8 has a unique circular light emitting portion. Also from this point, it turns out that the calcite type calcium carbonate obtained in Example 1 is a spherulite.

  Thus, the calcite-type calcium carbonate produced by the procedure of Example 1 is a spherulite and has a substantially spherical outer shape.

  As described above, the calcite-type calcium carbonate 2 obtained in a part of the carbonation step of adding carbon dioxide gas to the calcium hydroxide aqueous suspension is not a mere sphere but a spherulite. That is confirmed. The merit of being a spherulite is as described above, and has many advantages over a simple sphere.

  The calcite-type calcium carbonate 2 having a spherulite structure described in Example 1 is manufactured by the manufacturing process of FIG. In each of the manufacturing steps, when manufacturing calcite-type calcium carbonate having a spherulite structure, the device in each step produces calcite-type calcium carbonate 2 having a spherulite structure with more certainty and high accuracy. be able to. This will be described below.

(Part 1: Process control temperature of carbonation process)
In the carbonation step, the temperature in the carbonation step is controlled. At this time, it is preferable that the process control temperature in a carbonation process is 18 to 65 degreeC over the whole carbonation process.

  Table 1 is a table | surface at the time of changing process control temperature throughout the carbonation process variously.

  Table 1 shows the results of Comparative Examples 1 and 2 and Examples 1 to 5. 9 to 14 are electron micrographs of calcium carbonate obtained in the examples and comparative examples shown in Table 1. The examples were manufactured as calcite-type calcium carbonate, but the comparative examples were calcite-type calcium carbonate that did not produce spherulites or calcium carbonate that could not be converted to calcite-type. Or For this reason, in description of drawing, although it may only describe as calcium carbonate, it is not the description which intends that it is not calcite type calcium carbonate.

  FIG. 9 is an electron micrograph of calcium carbonate of Comparative Example 1 described in Table 1. FIG. 10 is an electron micrograph of calcium carbonate of Example 2 shown in Table 1. FIG. 11 is an electron micrograph of calcium carbonate of Example 3 described in Table 1. FIG. 12 is an electron micrograph of the calcium carbonate of Example 4 described in Table 1. FIG. 13 is an electron micrograph of calcium carbonate of Example 5 shown in Table 1. FIG. 14 is an electron micrograph of calcium carbonate of Comparative Example 2 described in Table 1.

  The manufacturing steps and results of Comparative Examples 1 and 2 and Examples 1 to 5 will be described.

(Comparative Example 1)
The amount of calcium hydroxide aqueous suspension used, the amount of carbon dioxide gas used in the carbonation step, and the reaction rate are the same as those described in Example 1. The only difference from Example 1 is that the process control temperature is 15 ° C. ± 1 ° C.

  As is clear from Table 1 and FIG. 9, Comparative Example 1 does not produce spherulites. That is, when the process control temperature is 15 ° C., which is less than 18 ° C., it is clear from experiments that calcite-type calcium carbonate having spherulites cannot be obtained. In other words, in the calcium carbonate of Comparative Example 1, the shape of the primary particles becomes cubic. Here, the shape and arrangement of the primary particles in Table 1 indicate the internal structure.

(Example 2)
In Example 2, the amount of calcium hydroxide aqueous suspension used, the amount of carbon dioxide gas used in the carbonation step, and the reaction rate are the same as those described in Example 1. Only the process control temperature is set to 18 ° C. ± 1 ° C. is different from Example 1.

  In Example 2, as is clear from Table 1 and FIG. 10, a plurality of plate-like crystals are grown radially. Although it is plate-like, it is in a state showing spherulites. That is, it is understood that the lower limit of the process control temperature is preferably 18 ° C.

Example 1
Example 1 is as described in Example 1, and shows a spherulite in which a plurality of crystals are grown in a plurality of directions (particularly in a radial shape). In addition, the outer shape also has a substantially spherical shape, and it can be seen from a certain position that a plurality of crystals are spherulites radially grown to substantially the same length and have a substantially spherical shape.

  For this reason, it is understood that the process control temperature of 30 ° C. is a temperature suitable for obtaining spherulite and substantially spherical calcite type calcium carbonate.

(Example 3)
In Example 3, the amount of calcium hydroxide aqueous suspension used, the amount of carbon dioxide gas used in the carbonation step, and the reaction rate are the same as those described in Example 1. The only difference from Example 1 is that the process control temperature is only 40 ° C. ± 1 ° C.

  As is apparent from Table 1 and FIG. 11, the calcite-type calcium carbonate obtained in Example 3 has spherulites. In addition, the outer shape has a substantially spherical shape. From this, it is understood that the process control temperature of 40 ° C. is a temperature suitable for obtaining spherulite and substantially spherical calcite type calcium carbonate.

Example 4
In Example 4, the amount of calcium hydroxide aqueous suspension used, the amount of carbon dioxide gas used in the carbonation step, and the reaction rate are the same as those described in Example 1. The only difference from Example 1 is that the process control temperature is only 50 ° C. ± 1 ° C.

  As is clear from Table 1 and FIG. 12, in the internal structure of calcite-type calcium carbonate obtained at a process control temperature of 50 ° C., a plurality of crystals grow radially from a certain position. That is, the calcite type calcium carbonate of Example 5 has spherulites.

(Example 5)
In Example 5, the amount of calcium hydroxide aqueous suspension used, the amount of carbon dioxide gas used in the carbonation step, and the reaction rate are the same as those described in Example 1. The only difference from Example 1 is that the process control temperature is set to 60 ° C. ± 1 ° C.

  The calcite type calcium carbonate of Example 5 shows a radial polycrystal as is apparent from Table 1 and FIG. Since it is a radial polycrystal, it has a part of spherulite as its structure. However, the growth orientation and length of the plurality of crystals are non-uniform, and the outer shape shows a spindle shape.

(Comparative Example 2)
In Comparative Example 2, the amount of calcium hydroxide aqueous suspension used, the amount of carbon dioxide gas used in the carbonation step, and the reaction rate are the same as those described in Example 1. The only difference from Example 1 is that the process control temperature is set to 70 ° C. ± 1 ° C.

  In the calcium carbonate of Comparative Example 2, spherulites are not shown, and acicular crystals are precipitated. In addition, in the calcium carbonate obtained at a process control temperature of 70 ° C., needle-like crystals are randomly grown in addition to spindle-shaped aggregates. This acicular crystal was confirmed to be an aragonite phase.

  In this respect, when a process control temperature of 70 ° C. is reached, the obtained calcium carbonate cannot produce a radial polycrystal. As can be seen from the experimental results in Table 1 above, in order to obtain calcite-type calcium carbonate having a radial polycrystal in a production process including a carbonation process, the process control temperature throughout the carbonation process is: It is preferable that it is 18 to 65 degreeC.

(Part 2: Process control temperature: Part 1 based on carbonation rate)
In the carbonation step, not only the temperature range throughout the carbonation step is regulated, but also the relationship between the carbonation rate of the calcium hydroxide aqueous suspension in the carbonation step and the process control temperature can be controlled. It is suitable for the production of calcite-type calcium carbonate having the above-mentioned average particle diameter while having a spherulite structure.

  First, in the carbonation step, when the carbonation rate of the calcium hydroxide aqueous suspension is less than 10%, the process control temperature is 20 ° C to 55 ° C, and more preferably 25 ° C to 35 ° C. . Table 2 is a table | surface which shows the result of the calcite type | mold calcium carbonate manufactured when this carbonation rate is less than 10%.

  Table 2 shows the results of Examples 6 to 9 and Comparative Example 3 in the case where the process control temperature when the carbonation rate was less than 10% was variously changed. FIG. 15 is an electron micrograph of calcium carbonate obtained in Example 6. FIG. 16 is an electron micrograph of calcium carbonate obtained in Example 7. FIG. 17 is an electron micrograph of calcium carbonate obtained in Example 8. 18 is an electron micrograph of calcium carbonate obtained in Example 9. FIG. FIG. 19 is an electron micrograph obtained in Comparative Example 3.

  The production steps and results of Examples 6 to 9 and Comparative Example 3 shown in Table 2 will be described.

(Example 6)
In Example 6, the amount of calcium hydroxide aqueous suspension used, the amount of carbon dioxide gas used in the carbonation step, and the reaction rate are the same as those described in Example 1. In Example 6, the start temperature of the carbonation process was set to 20 ° C. ± 1 ° C., and this process control temperature was maintained up to a carbonation rate of 10%. After the carbonation rate exceeded 10%, the process control temperature was set to 30%. It is a calcite-type calcium carbonate produced by setting the temperature to ± 1 ° C.

  The calcite-type calcium carbonate of Example 6 obtained in this way has a plate-like radial shape as apparent from Table 2 and FIG. Since it is a plate-like radial shape, it can be seen that it shows spherulites. As a result, it can be seen that the process control temperature at a carbonation rate of less than 10% may be 20 ° C. or higher.

(Example 7)
In Example 7, the amount of calcium hydroxide aqueous suspension used, the amount of carbon dioxide gas used in the carbonation step, and the reaction rate are the same as those described in Example 1. In Example 7, the start temperature of the carbonation process was set to 25 ° C. ± 1 ° C., and this process control temperature was maintained up to a carbonation rate of 10%. After the carbonation rate exceeded 10%, the process control temperature was set to 30 It is a calcite-type calcium carbonate produced by setting the temperature to ± 1 ° C.

  As is apparent from Table 2 and FIG. 16, the calcite-type calcium carbonate obtained in Example 7 shows spherulites. In addition, the outer shape is also substantially spherical. From this result, it can be seen from the experimental results of Example 7 that the process control temperature at a carbonation rate of less than 10% is more preferably 25 ° C. to 35 ° C.

(Example 8)
In Example 8, the amount of calcium hydroxide aqueous suspension used, the amount of carbon dioxide gas used in the carbonation step, and the reaction rate are the same as those described in Example 1. In Example 8, the start temperature of the carbonation process is 40 ° C. ± 1 ° C., this process control temperature is maintained up to a carbonation rate of 10%, and after the carbonation rate exceeds 10%, the process control temperature is set to 30%. It is a calcite-type calcium carbonate produced by setting the temperature to ± 1 ° C.

  As is apparent from Table 2 and FIG. 17, spherulites are shown. Although the outer shape is almost spherical, the shape of the substantially spherical shape is not perfect, and in order to obtain calcite-type calcium carbonate showing spherulites, the carbonation rate is less than 10%. It can be seen that the process control temperature is preferably 20 ° C to 55 ° C, more preferably 25 ° C to 35 ° C.

Example 9
In Example 6, the amount of calcium hydroxide aqueous suspension used, the amount of carbon dioxide gas used in the carbonation step, and the reaction rate are the same as those described in Example 1. In Example 6, the start temperature of the carbonation process was 55 ° C. ± 1 ° C., and this process control temperature was maintained up to a carbonation rate of 10%. After the carbonation rate exceeded 10%, the process control temperature was 30 It is a calcite-type calcium carbonate produced by setting the temperature to ± 1 ° C.

  As is apparent from Table 2 and FIG. 18, the calcite-type calcium carbonate of Example 9 produces spherulites. Moreover, the external shape also shows a substantially spherical shape or a shape close thereto. However, the particle size varies. However, in any case, it can be seen that the process control temperature at a carbonation rate of less than 10% is preferably 20 ° C to 55 ° C, more preferably 25 ° C to 35 ° C.

(Comparative Example 3)
In Comparative Example 3, the amount of calcium hydroxide aqueous suspension used, the amount of carbon dioxide gas used in the carbonation step, and the reaction rate are the same as those described in Example 1. In Comparative Example 3, the start temperature of the carbonation process was set to 60 ° C. ± 1 ° C., this process control temperature was maintained up to a carbonation rate of 10%, and after the carbonation rate exceeded 10%, the process control temperature was set to 30 It is a calcite-type calcium carbonate produced by setting the temperature to ± 1 ° C.

  As is clear from Table 2 and FIG. 19, the calcium carbonate obtained in Comparative Example 3 is not spherulite. This also shows that the process control temperature is preferably 20 ° C to 55 ° C, and more preferably 25 ° C to 35 ° C when the carbonation rate is less than 10%.

  In particular, when it is required that the particle diameters are uniform and the outer shape is substantially spherical, the difference between Example 7 and Example 8 is shown in FIGS. It can be seen from the 17 results. In this respect, the upper limit temperature of the process control temperature is appropriately 55 ° C. if only the spherulite is required, and the upper limit temperature is 35 ° C. considering the substantially spherical outer shape and the uniform particle size. Is appropriate.

(Process control temperature: 2 by carbonation rate)
On the other hand, in the carbonation step, it is also preferred that the process control temperature is controlled when the carbonation rate of the calcium hydroxide aqueous suspension is 10% or more. When the carbonation rate of the calcium hydroxide aqueous suspension is 10% or more, the process control temperature is 20 ° C to 60 ° C, and more preferably 20 ° C to 40 ° C. Table 3 is a table | surface which shows the result of the calcite type | mold calcium carbonate manufactured when this carbonation rate is 10% or more.

  Table 3 shows the results of Examples 10 to 12 and Comparative Examples 4 and 5 in the case where the process control temperature when the carbonation rate is 10% or later is variously changed. FIG. 20 is an electron micrograph of calcium carbonate obtained in Comparative Example 4. FIG. 21 is an electron micrograph of calcium carbonate obtained in Example 10. FIG. 22 is an electron micrograph of calcium carbonate obtained in Example 11. 23 is an electron micrograph of calcium carbonate obtained in Example 12. FIG. FIG. 24 is an electron micrograph obtained in Comparative Example 5.

  In this experiment, calcium carbonate in each of the examples and comparative examples was manufactured, and the optimum value of the process control temperature condition at a carbonation rate of 10% or more was confirmed.

(Comparative Example 4)
In Comparative Example 4, the amount of calcium hydroxide aqueous suspension used, the amount of carbon dioxide gas used in the carbonation step, and the reaction rate are the same as those described in Example 1. In Comparative Example 4, the start temperature of the carbonation process was set to 30 ° C. ± 1 ° C., and this process control temperature was maintained up to a carbonation rate of 10%. After the carbonation rate exceeded 10%, the process control temperature was set to 18%. It is calcium carbonate manufactured by setting it to +/- 1 degreeC.

  As is apparent from Table 3 and FIG. 20, the calcium carbonate obtained in Comparative Example 4 is an aggregate of plate-like crystals, and is only an aggregate of plate-like primary particles. For this reason, the calcium carbonate in Comparative Example 4 does not have spherulites. For this reason, if the process control temperature at a carbonation rate of 10% or more is less than 20 ° C., it is insufficient for obtaining calcite-type calcium carbonate having spherulites.

(Example 10)
In Example 10, the amount of calcium hydroxide aqueous suspension used, the amount of carbon dioxide gas used in the carbonation step, and the reaction rate are the same as those described in Example 1. In Example 10, the start temperature of the carbonation process was set to 30 ° C. ± 1 ° C., and this process control temperature was maintained up to a carbonation rate of 10%. After the carbonation rate exceeded 10%, the process control temperature was set to 20%. It is calcium carbonate manufactured by setting it to +/- 1 degreeC.

  The calcite type calcium carbonate obtained in Example 10 shows spherulites as is apparent from Table 3 and FIG. Further, although the particle diameter varies, the outer shape is also substantially spherical. As a result, a process control temperature of 20 ° C. or higher at a carbonation rate of 10% or more is suitable for obtaining calcite-type calcium carbonate having spherulites and substantially spherical shapes.

(Example 11)
In Example 11, the amount of calcium hydroxide aqueous suspension used, the amount of carbon dioxide gas used in the carbonation step, and the reaction rate are the same as those described in Example 1. In Example 11, the start temperature of the carbonation process is set to 30 ° C. ± 1 ° C., and this process control temperature is maintained up to a carbonation rate of 10%. After the carbonation rate exceeds 10%, the process control temperature is set to 40%. It is calcium carbonate manufactured by setting it to +/- 1 degreeC.

  The calcite type calcium carbonate obtained in Example 11 shows spherulites as is apparent from Table 3 and FIG. Further, the outer shape also shows a substantially spherical shape, and it can be seen that this process control temperature is suitable for obtaining calcite-type calcium carbonate which is spherulite and is substantially spherical.

(Example 12)
In Example 12, the amount of calcium hydroxide aqueous suspension used, the amount of carbon dioxide gas used in the carbonation step, and the reaction rate are the same as those described in Example 1. In Example 12, the start temperature of the carbonation process is set to 30 ° C. ± 1 ° C., and this process control temperature is maintained up to a carbonation rate of 10%. After the carbonation rate exceeds 10%, the process control temperature is set to 60 ° C. It is calcium carbonate manufactured by setting it to +/- 1 degreeC.

  The calcite type calcium carbonate obtained in Example 12 shows spherulites as is apparent from Table 3 and FIG. Further, the outer shape also shows a substantially spherical shape, and it can be seen that this process control temperature is suitable for obtaining calcite-type calcium carbonate which is spherulite and is substantially spherical. However, variation occurs in the particle size and the like. For this reason, it is considered that the upper limit of the process control temperature at a carbonation rate of 10% or more is preferably 60 ° C.

(Comparative Example 5)
In Comparative Example 5, the amount of calcium hydroxide aqueous suspension used, the amount of carbon dioxide gas used in the carbonation step, and the reaction rate are the same as those described in Example 1. In Comparative Example 5, the start temperature of the carbonation process was set to 30 ° C. ± 1 ° C., and this process control temperature was maintained up to a carbonation rate of 10%. After the carbonation rate exceeded 10%, the process control temperature was set to 65 It is calcium carbonate manufactured by setting it to +/- 1 degreeC.

  As is apparent from Table 3 and FIG. 24, Comparative Example 5 is a spindle-shaped aggregate and does not form spherulites. That is, it becomes an aggregate of primary particles. For this reason, when the process control temperature after the carbonation rate of 10% exceeds 60 ° C., calcite-type calcium carbonate having spherulites cannot be obtained.

  From the above experimental results, it can be seen that the process control temperature at a carbonation rate of 10% or more is 20 ° C. to 60 ° C., more preferably 20 ° C. to 40 ° C.

  In particular, in view of obtaining a substantially spherical shape from FIGS. 23, 24, etc., it is particularly preferably 20 to 40 ° C.

      (Part 3: Reaction rate management)

  In the above, the process control temperature control has been described.

  In addition to the process control temperature, it is also preferable to control the reaction rate in order to obtain a calcite-type calcium carbonate having a crystal structure as a spherulite and having an outer shape that is nearly spherical and also has a uniform particle size. .

  In the carbonation step, the reaction rate when the carbonation rate is 1% to 5% is 2 mol% / min or less, and the reaction rate when the carbonation rate is 5 to 10% is 0.16 mol% / min to 0.24 mol% / It is preferable that the reaction rate after the carbonation rate of 10% or less is 1.1 mol / min or less.

  Here, in the calcite type calcium carbonate, an embryo which is a source of stable nuclei of spherulites is first formed by a step including a carbonation step of adding carbon dioxide gas to a calcium hydroxide aqueous suspension. Here, the number of embryos is preferably controlled. Next, as the carbonation process proceeds, the embryo grows into stable nuclei. As the carbonation process proceeds further, stable nuclei grow further. At this time, it is preferable to control so that only stable nuclei grow.

  Here, Embryo is formed at a carbonation rate of 1% to 5%, particularly at a carbonation rate of 2% to 3%. For this reason, in order to control the number of embryos, it is important to control the reaction rate within this carbonation rate range.

  Stable nuclei grow in the carbonation rate range of 5% to 10%. In order to allow stable nuclei to grow properly, it is important to control the reaction rate at this carbonation rate. It is important to control the reaction rate so that no new nucleation occurs even when the carbonation rate is 10% or more.

  In order to obtain calcite-type calcium carbonate having spherulites by such crystal growth, it is preferable to control the reaction rate in accordance with the progress of the carbonation rate. As an example, the control according to the following procedure described above is preferable.

(Range 1) When the carbonation rate is 1% to 5% In this range, the reaction rate is preferably controlled to 2 mol% / min or less. This is because the number of embryos from which stable nuclei are derived is controlled by this reaction rate.

(Range 2) Carbonation rate of 5% to 10% In this range, the reaction rate is preferably controlled to 0.16 mol% / min to 0.24 mol% / min. This is because, by this reaction rate, only stable nuclei can be grown while growing Embrio into stable nuclei.

(Range 3) When the carbonation rate is 10% or more In this range, the reaction rate is preferably controlled to 1.1 mol% / min or less. This is because, by this reaction rate, only stable nuclei can be sufficiently grown to obtain spherulites.

  As described above, controlling the reaction rate according to the carbonation rate makes it possible to produce calcite-type calcium carbonate having stable spherulites and having a uniform particle size.

  Here, the experimental result regarding the control of the reaction rate described above is shown. The inventor has confirmed that the control of the reaction rate is appropriate by changing the reaction rate depending on the difference in carbonation rate. The results of the experiment are shown in Table 4.

  In Table 4, it describes so that a carbonation rate and reaction rate may respond | correspond. The numerical value described in the lower column (in particular) of the carbonation rate indicates the reaction rate (unit: mol% / min).

  Table 4 shows the results of Comparative Example 6 and Examples 13 to 15 in which this reaction rate was varied. FIG. 25 is an electron micrograph of calcium carbonate obtained in Comparative Example 6. FIG. 26 is an electron micrograph of calcium carbonate obtained in Example 13. FIG. 27 is an electron micrograph of calcium carbonate obtained in Example 14. 28 is an electron micrograph of calcium carbonate obtained in Example 15. FIG.

  The manufacturing process and results in Comparative Example 6 and Examples 13 to 15 are shown below.

(Comparative Example 6)
In Comparative Example 6, the mixed gas blowing speed from the reaction start to the carbonation rate of 5% was 3800 ml / min, the mixed gas blowing speed from the carbonation rate of 5% to the carbonation rate of 10% was 220 ml / min, Calcium carbonate obtained in the same production process as in Example 1 except that the mixed gas blowing speed at a rate of 10% or more was 1950 ml / min. According to the mixed gas blowing speed, in Comparative Example 6, the reaction rate when the carbonation rate is 1% to 5% (range 1) is 2.5 mol% / min, and the carbonation rate is 5% to 10%. % (Range 2) is 0.15 mol% / min, and when the carbonation rate is 10% or more (range 3), the reaction rate is calcium carbonate obtained at 1.15 mol% / min.

  As is apparent from Table 4 and FIG. 25, the calcium carbonate of Comparative Example 6 becomes a fine particle aggregate and does not show spherulites. For this reason, it turns out that the calcite type | mold calcium carbonate which has a spherulite cannot be obtained when reaction rate remove | deviates from the range mentioned above.

(Example 13)
In Example 13, the mixed gas blowing speed from the start of the reaction to the carbonation rate of 5% was 3000 ml / min, the mixed gas blowing speed from the carbonation rate of 5% to the carbonation rate of 10% was 350 ml / min, and the carbonation. This is a calcite-type calcium carbonate obtained in the same process as in Example 1 except that the mixed gas blowing speed at a rate of 10% or more was 1800 ml / min.

  With such blowing speed, the reaction rate at a carbonation rate of 1% to 5% (range 1) is 2 mol% / min, and the reaction rate at a carbonation rate of 5% to 10% (range 2) is 0.00. The reaction rate when the carbonation rate is 23 mol% / min and the carbonation rate is 10% or more (range 3) is 1.1 mol% / min, and the results of the produced calcite-type calcium carbonate are shown. This condition is within the range of the optimum value described above in each of the ranges 1 to 3.

  The calcite type calcium carbonate obtained in Example 13 is a spherulite having an average particle diameter of 5 μm, as is apparent from Table 4 and FIG. Further, the outer shape is almost spherical, and it can be seen that it is a calcite-type calcium carbonate that can be ideally used as a filler.

(Example 14)
In Example 14, the mixed gas blowing rate from the start of the reaction to the carbonation rate of 5% was 15 ml / min, the mixed gas blowing rate from the carbonation rate of 5% to the carbonation rate of 10% was 240 ml / min, A calcite-type calcium carbonate obtained in the same process as in Example 1 except that Example 1 was used except that the mixed gas blowing speed after a rate of 10% was 1500 ml / min.

  With such blowing speed, Example 14 had a carbonation rate of 1% to 5% (range 1), a reaction rate of 0.22 mol% / min, and a carbonation rate of 5% to 10% (range 2). The reaction rate at 0.2 mol% / min and the reaction rate at a carbonation rate of 10% or more (range 3) is 0.9 mol% / min. is there. This condition is within the range of the optimum value described above in each of the ranges 1 to 3.

  The calcite type calcium carbonate obtained in Example 14 is a spherulite having an average particle diameter of 10 μm, as is apparent from Table 4 and FIG. Further, the outer shape is almost spherical, and it can be seen that it is a calcite type calcium carbonate that can be ideally used as a filler.

(Example 15)
In Example 15, the reaction rate was 0.005 mol% / min when the carbonation rate was 1% to 5% (range 1), and the reaction rate when the carbonation rate was 5% to 10% (range 2) was 0.00. The reaction rate at 16 mol% / min and a carbonation rate of 10% or more (range 3) is 0.9 mol% / min. The result of the produced calcite calcium carbonate is shown. This fourth stage condition is within the range of the optimum value described above in each of the ranges 1 to 3.

  The calcite-type calcium carbonate obtained in Example 15 is spherulite and has a substantially spherical outer shape, as is apparent from Table 4 and FIG. At this time, the average particle diameter is 40 μm. By processing at a reaction rate falling within the above range, calcite-type calcium carbonate that is spherulite is obtained.

  Thus, by controlling the reaction rate according to the carbonation rate, it is possible to obtain calcite-type calcium carbonate that is spherulite and has a substantially spherical outer shape. In particular, the particle size can be adjusted.

(Addition of condensed phosphoric acid)
Next, in order to grow spherulites more efficiently, a case will be described in which a step of adding condensed phosphoric acid or an alkali metal salt thereof is added before or during the carbonation step. At any time before or during the carbonation step, the condensed phosphoric acid or its alkali metal salt is added once or more in the range of 0.03% to 1.5% by weight with respect to the calcium hydroxide charged. The step of adding is further included to produce calcite-type calcium carbonate.

  The process of adding condensed phosphoric acid or an alkali metal salt thereof has advantages that the growth of spherulites is promoted and the particle diameters are easily made uniform. Here, the condensed phosphoric acid or the alkali metal salt thereof is suitably added at least at any point before or during the carbonation step, but when the carbonation rate is less than 25%, 1 It is more appropriate to add only once. By adding only once at this stage, in the growth of the spherulites, each of the plurality of crystals grows almost identically in a plurality of radial directions, and the outer shape tends to be more spherical.

  (Embodiment 3)

Next, a third embodiment will be described.
In the third embodiment, a device for the dropping step for forming the hydroxyapatite layer 3 will be described. As described in the first embodiment, the outer periphery of the calcite-type calcium carbonate 2 having a spherulite structure can be covered with the hydroxyapatite layer 3 by the dropping step.

  At this time, the formation mode of the hydroxyapatite layer 3 can be changed according to the solution temperature of the slurry solution in the dropping step. Alternatively, by controlling the molar ratio between calcite-type calcium carbonate 2 and phosphorus such as phosphoric acid used in the dropping step, the formation mode of the hydroxyapatite layer 3 can also be changed.

  The suitability of the calcium carbonate composite 1 for use can be variously adjusted by changing the formation mode of the hydroxyapatite layer 3.

(Production condition 1: Solution temperature range 1 in the dropping step)
It is preferable that the solution temperature of the slurry solution (slurry solution containing spherulite-structured calcite-type calcium carbonate 2 in FIG. 5) when the dropping step is executed is controlled to 50 ° C. to 80 ° C. By controlling the temperature of the slurry solution at 50 ° C. to 80 ° C., the hydroxyapatite layer 3 covering the outer periphery of the calcite-type calcium 2 having a spherulite structure has a scaly shape. (It will be described later together with other variations).

  By forming the scale-like hydroxyapatite layer 3, the surface area of the entire hydroxyapatite layer 3 is increased. In addition, since the hydroxyapatite layer 3 is covered with many shapes such as scales due to the scale shape, a lot of scales and gaps may be generated.

  As a result of such a scale-like shape, the hydroxyapatite layer 3 tends to contain oil. For example, when the calcium carbonate complex 1 is used in cosmetics or a skin cream, it becomes easy to contain oil, so that the skin is well-adapted and the adsorptivity to the skin is improved. Increased, resulting in a merit that the makeup is not easily broken.

  Of course, even when the calcium carbonate composite 1 is used for pigments, paints, etc., the hydroxyapatite layer 3 is scaly, so that the oil content is improved and the coating performance and durability after coating are improved. There is.

(Production condition 2: Solution temperature range 2 in the dropping step)
The solution temperature of the slurry solution (slurry solution containing the calcite-type calcium carbonate 2 having a spherulite structure in FIG. 5) when the dropping step is executed is controlled to 10 ° C. to 50 ° C. or 80 ° C. to 100 ° C. It is preferable. The hydroxide apatite layer 3 covering the outer periphery of the calcite-type calcium 2 having a spherulite structure has a granular shape by controlling the solution temperature of the slurry solution to 10 ° C. to 50 ° C. or 80 ° C. to 100 ° C. It becomes like this.

  By being the granular hydroxyapatite layer 3, the surface of the hydroxyapatite layer 3 becomes smooth. Unlike the scale shape, if it is granular, the surface of the hydroxyapatite layer 3 is covered with fine elements. As a result, naturally, the surface of the hydroxyapatite layer 3 becomes smoother and a moist feeling is obtained.

  In the case of the calcium carbonate composite 1 having such a granular hydroxyapatite layer 3 having a smooth surface, the slipperiness is increased. For this reason, when this calcium carbonate complex 1 is added to cosmetics, skin creams, etc., the slipperiness becomes high, and a smooth and moist feel is generated.

  Alternatively, when it is added to a pigment or paint, it becomes smooth and smooth as well. As a result, it is possible to achieve a composition that gives priority to smoothness and smoothness as a whole.

(Production condition 3: Adjustment of the ratio of calcium and phosphorus)
It is preferable that Ca / P which is a molar ratio of calcite type calcium carbonate 2 and phosphorus, such as phosphoric acid dripped at a dripping process, is 1.8-100.

  This is because when the ratio is within this range, the hydroxyapatite layer 3 has a scale-like shape or a calcium carbonate aggregate in which calcium carbonate complexes are aggregated. In any case, it is suitable for addition to compositions such as pigments, cosmetics, cosmetics, dentifrices, paints, abrasives and polishing aids.

  On the other hand, when it is out of the above range, the calcium carbonate composite produced may not have the hydroxyapatite layer 3 formed or may have a different heterogeneous phase that is not desired to occur.

  As a result, the calcium carbonate composite 1 having a spherulite structure in which the target hydroxyapatite layer 3 covers the outer periphery cannot be produced. For this reason, it is preferable that Ca / P which is a molar ratio of calcite type | mold calcium carbonate 2 and phosphorus, such as phosphoric acid dripped at a dripping process, is 1.8-100.

    (Experimental result)

The experimental results for the above manufacturing conditions 1 to 3 will be described. Table 5 summarizes production conditions 1 to 3 of the experiment described in the third embodiment. In Table 5, Comparative Examples 10-12 and Examples 20-34 are shown. About each of a comparative example and an Example, only the typical thing is shown as a photograph.

(Comparative Example 10)
In Comparative Example 10, Ca / P is 27, the solution temperature of the slurry solution (hereinafter referred to as “solution temperature”) is 10 ° C. ± 1 ° C., and the dropping time in the dropping step (hereinafter referred to as “dropping time”) is It is a calcium carbonate composite manufactured under the condition of 30 minutes.
In Comparative Example 10, the hydroxyapatite layer is granular and can be used as a calcium carbonate composite, but due to the short dropping time, a portion where the growth of the hydroxyapatite layer seems to be insufficient was also generated. Comparative Example 10 is not a suitable manufacturing example due to the low energy efficiency of 10 ° C. or lower.

  FIG. 29 shows a photograph of a calcium carbonate composite in which a hydroxyapatite layer is not formed as in Comparative Example 10. FIG. 29 is an electron micrograph of a calcium carbonate composite in which a hydroxyapatite layer is not formed (the above production conditions 1 to 3 are not satisfied).

(Example 20)
Example 20 is a calcium carbonate composite having a Ca / P of 27, a solution temperature of 15 ° C. ± 1 ° C., and a dropping time of 120 minutes. Each of the manufacturing conditions of Example 20 satisfies the manufacturing conditions 2 and 3 described above.

  As a result, the calcium carbonate composite of Example 20 has a granular hydroxyapatite layer and is a calcium carbonate composite that can be used as an additive to various target compositions. In particular, since the hydroxyapatite layer is granular, the cosmetic product to which the calcium carbonate composite of Example 20 is added has a merit that it is smooth and moist.

(Example 21)
Example 21 is a calcium carbonate composite having a Ca / P of 27, a solution temperature of 20 ° C. ± 1 ° C., and a dropping time of 120 minutes. Each of the manufacturing conditions of Example 20 satisfies the manufacturing conditions 2 and 3 described above.

  As a result, the calcium carbonate composite of Example 21 has a granular hydroxyapatite layer and is a calcium carbonate composite that can be used as an additive to various target compositions. In particular, since the hydroxyapatite layer is granular, the cosmetic product to which the calcium carbonate composite of Example 21 is added has a merit that it is smooth and moist.

  FIG. 30 shows a calcium carbonate composite in which a granular hydroxyapatite layer such as Examples 20 and 21 is formed. FIG. 30 is an electron micrograph of a calcium carbonate composite having a granular hydroxyapatite layer produced by satisfying production conditions 2 and 3.

(Example 22)
Example 22 is a calcium carbonate composite having a Ca / P of 27, a solution temperature of 30 ° C. ± 1 ° C., and a dropping time of 120 minutes. Each of the manufacturing conditions of Example 20 satisfies the manufacturing conditions 2 and 3 described above.

  As a result, the calcium carbonate composite of Example 22 has a granular hydroxyapatite layer and is a calcium carbonate composite that can be used as an additive to various target compositions. In particular, since the hydroxyapatite layer is granular, the cosmetic product to which the calcium carbonate composite of Example 22 is added has the advantage that it is smooth and moist.

(Example 23)
Example 23 is a calcium carbonate composite having a Ca / P of 27, a solution temperature of 50 ° C. ± 1 ° C., and a dropping time of 120 minutes. Each of the manufacturing conditions of Example 23 satisfies the manufacturing conditions 2 and 3 described above.

  As a result, the calcium carbonate composite of Example 23 has a scaly hydroxyapatite layer and is a calcium carbonate composite that can be used as an additive to various target compositions. In particular, since the hydroxyapatite layer is scaly, the cosmetic product to which the calcium carbonate composite of Example 23 is added has an advantage that makeup collapse is unlikely to occur.

(Example 24)
Example 24 is a calcium carbonate composite having a Ca / P of 27, a solution temperature of 60 ° C. ± 1 ° C., and a dropping time of 120 minutes. Each of the manufacturing conditions of Example 24 satisfies the manufacturing conditions 1 and the manufacturing conditions 3 described above.

  As a result, the calcium carbonate composite of Example 20 has a scaly hydroxyapatite layer and is a calcium carbonate composite that can be used as an additive to various target compositions. Since the acid apatite layer is scaly, the cosmetic to which the calcium carbonate composite of Example 24 is added has an advantage that makeup collapse is unlikely to occur.

(Example 25)
Example 25 is a calcium carbonate composite having a Ca / P of 27, a solution temperature of 70 ° C. ± 1 ° C., and a dropping time of 120 minutes. Each of the manufacturing conditions of Example 25 satisfies the manufacturing conditions 1 and the manufacturing conditions 3 described above.

  As a result, the calcium carbonate composite of Example 25 has a scaly hydroxyapatite layer and is a calcium carbonate composite that can be used as an additive to various target compositions. In particular, since the hydroxyapatite layer is scaly, the cosmetic to which the calcium carbonate composite of Example 25 is added has a merit that makeup collapse is unlikely to occur.

  FIG. 31 shows a calcium carbonate composite having a scaly hydroxyapatite layer produced in Examples 23 to 25 and the like. FIG. 31 is an electron micrograph of a calcium carbonate composite that satisfies production conditions 1 and 3 and has a scaly hydroxyapatite layer.

(Example 26)
Example 26 is a calcium carbonate composite having a Ca / P of 27, a solution temperature of 80 ° C. ± 1 ° C., and a dropping time of 120 minutes. Each of the manufacturing conditions of Example 26 satisfies the manufacturing conditions 2 and 3 described above.

  As a result, the calcium carbonate composite of Example 26 has a granular hydroxyapatite layer and is a calcium carbonate composite that can be used as an additive to various target compositions. In particular, since the hydroxyapatite layer is granular, the cosmetic product to which the calcium carbonate composite of Example 26 is added has a merit that it is smooth and moist.

(Example 27)
Example 27 is a calcium carbonate composite having a Ca / P of 27, a solution temperature of 90 ° C. ± 1 ° C., and a dropping time of 120 minutes. Each of the manufacturing conditions of Example 26 satisfies the manufacturing conditions 2 and 3 described above.

  As a result, the calcium carbonate composite of Example 27 has a granular hydroxyapatite layer and is a calcium carbonate composite that can be used as an additive to various target compositions. In particular, since the hydroxyapatite layer is granular, the cosmetic product to which the calcium carbonate composite of Example 27 is added has a merit that it is smooth and moist.

(Example 28)
Example 28 is a calcium carbonate composite having a Ca / P of 27, a solution temperature of 95 ° C. ± 1 ° C., and a dropping time of 120 minutes. Each of the manufacturing conditions of Example 28 satisfies the above-described manufacturing condition 2 and manufacturing condition 3.

  As a result, the calcium carbonate composite of Example 28 has a granular hydroxyapatite layer and is a calcium carbonate composite that can be used as an additive to various target compositions. In particular, since the hydroxyapatite layer is granular, the cosmetic product to which the calcium carbonate composite of Example 28 is added has a merit that it is smooth and moist.

(Comparative Example 11)
Comparative Example 11 is a calcium carbonate composite having a Ca / P of 150, a solution temperature of 70 ° C. ± 1 ° C., and a dropping time of 30 minutes. The manufacturing condition 3 described above is not satisfied. As a result, the calcium carbonate composite obtained in Comparative Example 11 could not confirm the hydroxyapatite layer.

(Example 29)
Example 29 is a calcium carbonate composite manufactured under the conditions that Ca / P is 80, the solution temperature is 70 ° C. ± 1 ° C., and the dropping time is 30 minutes. Each of the manufacturing conditions of Example 29 satisfies the manufacturing conditions 1 and 3.

  As a result, the calcium carbonate composite of Example 29 has a scaly hydroxyapatite layer and is a calcium carbonate composite that can be used as an additive to various target compositions. In particular, since the hydroxyapatite layer is scaly, the cosmetic to which the calcium carbonate composite of Example 29 is added has an advantage that makeup collapse is unlikely to occur.

(Example 30)
Example 30 is a calcium carbonate composite manufactured under the conditions that Ca / P is 50, the solution temperature is 70 ° C. ± 1 ° C., and the dropping time is 30 minutes. Each of the manufacturing conditions of Example 30 satisfies the manufacturing conditions 1 and 3.

  As a result, the calcium carbonate composite of Example 30 is a calcium carbonate composite that has a scaly hydroxyapatite layer and can be used as an additive to various target compositions. In particular, since the hydroxyapatite layer is scaly, the cosmetic to which the calcium carbonate composite of Example 30 is added has a merit that makeup collapse is unlikely to occur.

(Example 31)
Example 31 is a calcium carbonate composite having a Ca / P of 27, a solution temperature of 70 ° C. ± 1 ° C., and a dropping time of 30 minutes. Each of the manufacturing conditions of Example 31 satisfies the manufacturing conditions 1 and 3.

  As a result, the calcium carbonate composite of Example 31 has a scaly hydroxyapatite layer and is a calcium carbonate composite that can be used as an additive to various target compositions. In particular, since the hydroxyapatite layer is scaly, the cosmetic product to which the calcium carbonate composite of Example 31 is added has the advantage that makeup collapse is unlikely to occur.

(Example 32)
Example 32 is a calcium carbonate composite having a Ca / P of 13, a solution temperature of 70 ° C. ± 1 ° C., and a dropping time of 30 minutes. Each of the manufacturing conditions of Example 32 satisfies manufacturing conditions 1 and 3.

  As a result, the calcium carbonate composite of Example 32 has a scaly hydroxyapatite layer and is a calcium carbonate composite that can be used as an additive to various target compositions. In particular, since the hydroxyapatite layer is scaly, the cosmetic product to which the calcium carbonate composite of Example 32 is added has an advantage that makeup collapse is unlikely to occur.

(Example 33)
Example 33 is a calcium carbonate composite manufactured under the conditions that Ca / P is 2, the solution temperature is 70 ° C. ± 1 ° C., and the dropping time is 30 minutes. Each of the manufacturing conditions of Example 33 satisfies the manufacturing condition 1 but is close to the limit value of the manufacturing condition 3.

  The calcium carbonate composite of Example 33 is an aggregate in which a plurality of single calcium carbonate composites are aggregated with each other. That is, a calcium carbonate aggregate in which a plurality of calcium carbonate complexes are aggregated is obtained.

  By becoming a calcium carbonate aggregate, the single size becomes larger when used as an additive, and variations in suitable usage are expanded.

(Example 34)
Example 34 is a calcium carbonate composite having a Ca / P of 1.8, a solution temperature of 70 ° C. ± 1 ° C., and a dropping time of 30 minutes. Each of the manufacturing conditions of Example 34 satisfies the manufacturing condition 1 but is a limit value of the manufacturing condition 3.

  The calcium carbonate composite of Example 34 is an aggregate in which a plurality of single calcium carbonate composites are aggregated with each other. That is, a calcium carbonate aggregate in which a plurality of calcium carbonate complexes are aggregated is obtained.

  By becoming a calcium carbonate aggregate, the single size becomes larger when used as an additive, and variations in suitable usage are expanded.

  The calcium carbonate aggregate obtained in Examples 33 and 34 is shown in FIG. FIG. 32 is an electron micrograph of calcium carbonate aggregates.

(Comparative Example 12)
Comparative Example 12 is a calcium carbonate composite having Ca / P of 165, a solution temperature of 70 ° C. ± 1 ° C., and a dropping time of 30 minutes. It does not meet part 3 of the manufacturing conditions.

  As a result, in Comparative Example 12, a heterogeneous phase was precipitated, and the target calcium carbonate composite was not obtained.

  From the experimental results in Table 5 above, it was confirmed that production conditions 1 to 3 were necessary in order to form an optimal hydroxyapatite layer.

  (Embodiment 4)

  Next, a fifth embodiment will be described.

  In the fourth embodiment, utilization of the calcium carbonate composite obtained in the first to third embodiments will be described. Since the calcium carbonate composite 1 blurs glossiness, it is used for various articles that require soft focus. Moreover, since it is a spherulite and an external shape becomes a substantially spherical shape or a substantially ellipsoidal shape, and its particle size is small, it is easy to mix with various articles | goods. In addition to being easily mixed, the calcium carbonate complex 1 is less likely to be broken or damaged in the mixing step or after mixing. For this reason, the utility is very high.

  For this reason, the calcium carbonate composite 1 is used as a filler of various materials. In other words, various materials including the calcium carbonate composite 1 described in the first to third embodiments as a filler have an advantage of improving the respective physical properties.

  Based on this glossiness (including strength and durability, of course), the calcium carbonate composite 1 obtained in Embodiments 1 and 2 may be mixed with a pigment. Or you may mix with cosmetics. This is because suppressing the gloss of any article increases the commercial value.

  Thus, the pigment and cosmetics containing the calcium carbonate composite 1 obtained in Embodiments 1 to 3 are excellent in suppressing gloss.

  The calcium carbonate composite 1 obtained in the first to third embodiments is also suitable for use as a substance for increasing the amount. Since there is a large amount of lime that is the basic raw material of the calcium carbonate composite 1, the calcium carbonate composite 1 manufactured by the manufacturing process described in the first to third embodiments can be manufactured in large quantities. is there.

  For example, it can be used as a filler. The filler can increase the volume of a material such as resin or rubber without changing the properties thereof. Since the calcium carbonate composite 1 obtained in Embodiments 1 to 3 has a spherulite and has an outer shape that is substantially spherical or substantially elliptical, it does not adversely affect the tactile sensation of the mixed material. Moreover, since it is a spherulite, since the calcium carbonate composite 1 is not destroyed or damaged after a mixing process or mixing, its availability is high. Thus, the filler containing the calcium carbonate composite 1 obtained in Embodiments 1 to 3 has high utility.

  As described above, the calcium carbonate composite 1 obtained in the first to third embodiments uses both the durability and the usability of the outer shape, which are characteristics of a substantially spherical shape while being spherulites, and the glossiness. Thus, it can be used for various articles. In addition, as described in the first embodiment, the presence of the hydroxyapatite layer 3 can reduce irritation to the human body and improve the affinity for the application target.

  As mentioned above, the calcium carbonate composite demonstrated in Embodiment 1-4 is an example explaining the meaning of this invention, and includes the deformation | transformation and remodeling in the range which does not deviate from the meaning of this invention.

1 Calcium carbonate composite 2 Calcite type calcium carbonate 3 Hydroxyapatite layer

Claims (18)

Calcite-type calcium carbonate having a spherulite structure;
A calcium carbonate composite comprising a hydroxyapatite layer formed on the outer periphery of the calcite-type calcium carbonate. The calcite type calcium carbonate having the spherulite structure is
Produced in a manufacturing process that includes a carbonation process in which carbon dioxide gas is added to a calcium hydroxide aqueous suspension,
The calcium carbonate composite according to claim 1, wherein each of the plurality of crystals is a polycrystalline body grown in a plurality of directions from a single position or a plurality of positions.   The calcium carbonate composite according to claim 2, wherein a process control temperature in the carbonation step of adding carbon dioxide gas to the calcium hydroxide aqueous suspension is 18 ° C to 65 ° C.   In the carbonation step, when the carbonation rate of the calcium hydroxide aqueous suspension is less than 10%, the process control temperature is 20 ° C to 55 ° C, more preferably 25 ° C to 35 ° C. The calcium carbonate complex according to claim 3.   In the carbonation step, when the carbonation rate of the calcium hydroxide aqueous suspension is 10% or more, the process control temperature is 20 ° C to 60 ° C, more preferably 20 ° C to 40 ° C. The calcium carbonate complex according to claim 3 or 4.   In the carbonation step, the reaction rate at a carbonation rate of 1 to 5% is 2 mol% / min or less, and the reaction rate at a carbonation rate of 5 to 10% is 0.16 mol% / min to 0.24 mol% / min. The calcium carbonate complex according to any one of claims 3 to 5, wherein the reaction rate at a carbonation rate of 10% or less is 1.1 mol / min or less.   At least at any point during or during the carbonation step, the condensed phosphoric acid or alkali metal salt thereof is added to the calcium hydroxide in the calcium hydroxide aqueous suspension with respect to the condensed phosphoric acid or alkali thereof. 7. The method of claim 2, further comprising the step of adding one or more times such that the phosphorus content in the metal salt is in the range of 0.03% to 1.5% by weight. Any one of the calcium carbonate composites.   The calcium carbonate complex according to any one of claims 2 to 7, wherein each of the plurality of crystals grows radially from one position to substantially the same length to form a spherulite and has a substantially spherical shape on the outer shape.   The hydroxyapatite layer is formed in a dropping step in which phosphoric acid or a phosphate solution is dropped into a slurry solution of calcite-type calcium carbonate having a spherulite structure obtained after the carbonation step. Item 9. A calcium carbonate complex according to any one of Items 1 to 8.   The calcium carbonate complex according to claim 9, wherein in the dropping step, a solution temperature of the slurry solution is controlled to 50 ° C. to 80 ° C.   The calcium carbonate composite according to claim 9, wherein in the dropping step, the solution temperature of the slurry solution is controlled to 10 ° C. to 50 ° C. or 80 ° C. to 100 ° C.   The calcium carbonate complex according to any one of claims 9 to 11, wherein Ca / P, which is a molar ratio between the calcite-type calcium carbonate and the phosphorus, is 1.8 to 100.   The calcium carbonate complex according to any one of claims 1 to 12, wherein the hydroxyapatite layer has a scale shape.   The calcium carbonate composite according to any one of claims 1 to 12, wherein the hydroxyapatite layer has a granular shape.   A calcium carbonate aggregate in which a plurality of the calcium carbonate complexes according to claim 1 are aggregated and bonded.   A composition to which the calcium carbonate complex according to any one of claims 1 to 14 is added.   The composition according to claim 16, wherein the composition is any one of a pigment, a cosmetic, a beauty agent, a dentifrice, a paint, an abrasive and a polishing aid. A carbonation step of adding carbon dioxide gas to the calcium hydroxide aqueous suspension;
A dropping step in which phosphoric acid or a phosphate solution is dropped into a slurry solution of calcite-type calcium carbonate having a spherulite structure obtained after the carbonation step, and
A method for producing a calcium carbonate composite in which a hydroxyapatite layer is formed on the outer periphery of the calcite-type calcium carbonate having a spherulite structure.