JP6437846B2 - Calcium carbonate complex - Google Patents

Description

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

Limestone (calcium carbonate) is one of the few resources produced in the country, used as limestone, calcined and used as quick lime (calcium oxide), used as slaked lime (calcium hydroxide) obtained by reacting quick lime with water, and Utilization is made as calcium carbonate obtained by reacting slaked lime emulsion with carbon dioxide gas.
In addition to sintering with clay to make cement, the limestone can be crushed into crushed stones or fillers (fillers) that can be used as fillers for paper and plastics.
As quicklime (calcium oxide), it is used for industrial applications such as soil improvers and iron and paper making, and as slaked lime (calcium hydroxide), it is used as a neutralizer and fertilizer.

  Calcium carbonate obtained by reacting a calcium hydroxide aqueous suspension with carbon dioxide gas is used as an industrial filler for plastics, rubber, sealants, etc., and is called calcium carbonate, just like crushed limestone. It is used. Therefore, in order to distinguish between them, calcium carbonate obtained by pulverizing limestone is called heavy calcium carbonate, and calcium carbonate obtained by reacting a calcium hydroxide aqueous suspension with carbon dioxide gas is called light calcium carbonate. It is common.

  However, there is a great difference in properties between heavy calcium carbonate and light calcium carbonate. Heavy calcium carbonate is pulverized limestone, so the particle size is at most micron order and the particle size distribution is wide. Also, the shape is non-uniform and the surface is angular. Therefore, heavy calcium carbonate is often used as a filler as a filler.

  On the other hand, light calcium carbonate changes the various conditions of carbonation reaction between a calcium hydroxide aqueous suspension and carbon dioxide gas, for example, reaction temperature and reaction time, thereby changing the spherical shape, cubic shape, spindle shape, needle Various shapes such as a plate shape and a plate shape are obtained, and characteristics such as dispersibility, fluidity, glitter and orientation can be obtained depending on the shape. Further, the particle size can be controlled widely from several tens of nm to several tens of μm, the particle size distribution width can be made very small, and the whiteness is also high. Light calcium carbonate is industrially used as a functional filler unlike heavy calcium carbonate.

  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. Further, since calcium carbonate has no 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 | suction performance and inferior to bioactivity.

  Under such circumstances, there has been proposed a composite technology for coating the surface of calcium carbonate with hydroxyapatite (see, for example, Patent Documents 1, 2, and 3).

  The complex in which the surface of calcium carbonate is coated with hydroxyapatite can enhance the adsorption performance and enhance the living activity by the functional group of hydroxyapatite. As a result, when added to an industrial product such as resin or paper, the adsorptivity with other substances at the time of mixing increases, and the durability and workability of the manufactured industrial product can be improved. Alternatively, when added to cosmetics, the adsorbability by functional groups and the increase in daily activity improve the familiarity with the skin and have the effect of reducing various adverse effects on the skin.

  Thus, by coating the surface of calcium carbonate with hydroxyapatite, which is calcium phosphate, the surface characteristics of calcium carbonate can be changed, and the reactivity and affinity not obtained with conventional calcium carbonate can be limited. It also leads to high added value of a certain resource.

JP 2006-44966 A JP-A-11-180705 JP 09-183617 A

  As described above, in the case of an additive 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 Documents 1 to 3 disclose a composite of calcium carbonate and hydroxyapatite.

  However, any of the composites of calcium carbonate and hydroxyapatite in any of Patent Documents 1 to 3 has little examination and consideration on the oil absorption. The composite of calcium carbonate and hydroxyapatite is mixed with industrial products such as resin and paper as described above. In such industrial products, oil is added as one of the mixtures.

  The manufactured industrial product may cause a problem such that the added oil component oozes out after manufacturing. Such oil leakage is required to be reduced by the composite of calcium carbonate and hydroxyapatite to be mixed. However, none of the composites of Patent Documents 1 to 3 disclose or consider a technique for improving the oil absorption. For this reason, there exists a problem which cannot prevent the leakage of the oil content of such manufactured industrial products.

  In addition, when the amount of oil absorption of the complex of calcium carbonate and hydroxyapatite is small, when this complex is mixed with cosmetics, the sebum from the skin is not sufficiently adsorbed and the familiarity with the skin is weak. In addition, sebum that could not be adsorbed also causes malodor. If the amount of oil absorption of the cosmetic is large, sebum is adsorbed from the skin, so that familiarity with the skin is maintained, and malodor due to excess sebum is reduced. However, since the composites of Patent Documents 1 to 3 do not have sufficient consideration for the oil absorption amount or are insufficient, such problems cannot be solved even if they are mixed with cosmetics.

  Patent Document 1 introduces a technique in which carbon dioxide gas is introduced into a calcium hydroxide aqueous suspension and phosphoric acid is mixed from the beginning of introduction of carbon dioxide gas until the end of carbonation at which the suspension reaches pH 7-8. Disclose. By starting the mixing of phosphoric acid, a method for producing composite particles of hydroxyapatite and calcium carbonate is disclosed.

  The technique disclosed in Patent Document 1 does not consider an increase in oil absorption. The (0006) stage of Patent Document 1 targets a composite of about 10 μm that is excellent in handling such as dehydration, drying, and powdering. Thus, in the composite which has a median diameter of about 10 micrometers, in the SEM photograph disclosed by patent document 7, the scale-like particle | grains of hydroxyapatite are not seen on the surface. Moreover, the slaked lime used has a particle size of 0.5 to 2 mm obtained by granulating slaked lime, and is not the use of powdery slaked lime that should be natural. Thus, since the composite has a large particle size and the hydroxyapatite formed on the surface is not scaly, the surface area per volume is small and the gap for taking in the oil is small.

  That is, the composite disclosed in Patent Document 1 is in a state where the amount of oil absorption is small, and has the problem of being a composite having a small amount of oil absorption as described above.

  Patent Document 2 discloses a method for producing a solid substance having at least a porous hydroxyapatite in which a calcium-containing solid substance is brought into contact with an aqueous solution containing phosphate ions and having a pH of 7.0 or higher.

  However, limestone, shells, sea urchin shells, corals, and the like are used as a calcium carbonate source as a calcium-containing solid substance, and the particle size of calcium carbonate serving as the core of the composite becomes extremely large. When the particle size is large, the surface area per volume becomes small as in Patent Document 1, and the oil absorption becomes small.

  Moreover, in the SEM photograph observed from the Example of patent document 2, the hydroxyapatite layer formed on the surface is a plate-like crystal having a thickness of 0.2 to 0.3 μm and a width of 4 to 6 μm, and has a surface area. There are also few gaps for taking in oil. Also in this point, the composite in Patent Document 2 remains in a state where the oil absorption amount is small.

  Patent Document 3 discloses a porous calcium carbonate compound composed of particles satisfying a plurality of parameters and relational expressions. Here, the oil absorption is 50 ml to 300 ml per 100 g of the composite. Patent Document 3 differs from Patent Documents 1 and 2 in that there are references and considerations regarding the amount of oil absorption. However, the amount of oil absorption per 100 g is not sufficient as a composite to be mixed with industrial products and cosmetics when the amount of oil absorption is about the above level. .

  In particular, Patent Document 3 considers only use development for cosmetics, and cannot fully cope with a case where a complex is mixed with an industrial product that does not cause oil leakage.

  For example, when mixing with industrial products, higher oil absorption is required to prevent oil leakage. The technique disclosed in Patent Document 3 does not consider this point.

  In addition, the compound disclosed in Patent Document 3 is a calcium carbonate compound in which parameters such as dispersibility and particle size distribution width are combined. In the (0008) stage of Patent Document 3, it is described that when the reaction amount of the phosphoric acid compound is increased beyond a certain level, an inflection point is generated and the BET specific surface area is not further increased.

  Since there is a linear relationship between the BET specific surface area and the oil absorption amount, even if the reaction amount with the phosphoric acid compound is increased, useful phosphorus cannot be linked to an increase in the oil absorption amount. Therefore, the compound of Patent Document 3 has an oil absorption amount of 200 ml / 100 g at the maximum based on the examples described in the document, and the oil absorption amount per 1 g of phosphorus calculated from the amount of phosphoric acid used is 13 ml / below g. At this level, there is a problem that it is difficult to say that the amount of oil absorption is sufficient for both industrial products and cosmetics.

  In particular, phosphorus is an expensive and scarce resource. When the oil absorption amount relative to the unit amount of phosphorus is low, a large amount of expensive and rare phosphorus is used in producing a composite having a sufficient oil absorption amount. This naturally has the problem of making the manufactured composite expensive. Furthermore, moreover, it is necessary to use a large amount of phosphorus, which is not preferable for the global environment and scarce resources.

The complex of hydroxyapatite and calcium carbonate of the prior art has a problem that the amount of oil absorption is small even if there is no consideration or examination for the amount of oil absorption. When the oil absorption amount is small, there is a problem that leakage of oil from the industrial product produced when mixed with the industrial product occurs. Alternatively, there is a problem that the familiarity of the cosmetics produced when mixed with the cosmetics is insufficient.
In view of these problems, an object of the present invention is to provide a calcium carbonate composite having an improved oil absorption per gram of phosphorus.

In view of the above problems, the calcium carbonate composite of the present invention includes calcium carbonate,
Consisting of a hydroxyapatite layer formed on the outer periphery of calcium carbonate,
The molar ratio of calcium and phosphorus (Ca / P) is 1.67-20,
Oil absorption state, and are more phosphorus 1g per 15ml / g,
Calcium carbonate has a crystallite size measured by X-ray diffraction of 0.04 μm or less,
The hydroxyapatite layer is scaly.

  The calcium carbonate composite of the present invention can increase the surface area per volume by making the particle size small and constant. Furthermore, since it can form as a layer which made the hydroxyapatite scaly, many gaps containing an oil component (total volume can be enlarged) can be performed. Together, the calcium carbonate composite of the present invention can realize a high oil absorption.

  Due to this high oil absorption, even when the calcium carbonate composite is mixed with an industrial product, the oil adsorbing power after production is high and leakage of the oil can be reduced. Moreover, when it mixes with cosmetics, the adsorption power of sebum is high and the familiarity to skin becomes high.

  In addition, by forming a hydroxyapatite layer having a functional group on the surface layer of the calcium carbonate composite, the adsorbing ability and the biological activity are increased, and the optimum utilization as various mixtures becomes possible. Further, it is possible to impart high oil absorption, and it is possible to effectively use expensive phosphorus.

  Thereby, even when a calcium carbonate composite is mixed with an industrial product, the oil content adsorption power after manufacture is high, and the leakage of an oil content can be reduced. Moreover, when it mixes with cosmetics, the adsorption power of sebum is high and the familiarity to skin becomes high.

  In addition, by forming a hydroxyapatite layer having a functional group on the surface layer of the calcium carbonate composite, the adsorbing ability and the biological activity are increased, and the optimum utilization as various mixtures becomes possible.

It is process drawing of the manufacturing process of the calcium carbonate complex in Embodiment 1 of this invention. It is a schematic diagram of the calcium carbonate composite in Embodiment 1 of this invention. It is a graph which shows the relationship between Ca / P and the oil absorption of a calcium carbonate complex. It is a graph which shows the confirmation result in the X-ray diffraction of the obtained powder in Embodiment 2 of this invention. It is an electron micrograph which shows the scale-like hydroxyapatite layer in the Example in Embodiment 2 of this invention. It is an electron micrograph which shows the scale-like hydroxyapatite layer in the Example in Embodiment 2 of this invention. 4 is an electron micrograph of a calcium carbonate composite in a comparative example in Embodiment 2.

The calcium carbonate composite according to the first aspect of the present invention includes calcium carbonate,
Consisting of a hydroxyapatite layer formed on the outer periphery of calcium carbonate,
The molar ratio of calcium and phosphorus (Ca / P) is 1.67-20,
The oil absorption is 15 ml / g or more per gram of phosphorus.

  With this configuration, it is possible to realize a calcium carbonate composite that improves the oil absorption amount in phosphorus, which is an expensive and rare substance, and provides merit by storing the oil when mixed with industrial products and cosmetics.

  In the calcium carbonate composite according to the second aspect of the present invention, in addition to the first aspect, calcium carbonate has a crystallite size of 0.04 μm or less as measured by X-ray diffraction.

  With this configuration, the calcium carbonate composite of the present invention can increase the surface area relative to the volume, and can increase the amount of oil absorption per gram of phosphorus.

  In the calcium carbonate composite according to the third invention of the present invention, in addition to the first or second invention, the calcium carbonate partially includes a carbonation step of adding carbon dioxide gas to the calcium hydroxide aqueous suspension. It is manufactured in the manufacturing process included.

  With this configuration, a suspension containing calcium carbonate can be produced from a calcium hydroxide aqueous suspension.

  In the calcium carbonate composite according to the fourth invention of the present invention, in addition to the third invention, the process control temperature of the calcium hydroxide suspension when adding carbon dioxide gas to the calcium hydroxide aqueous suspension. Is less than 30 ° C.

  With this configuration, the crystallite size in X-ray diffraction of calcium carbonate constituting the calcium carbonate composite can be made 0.04 μm or less. As a result, the oil absorption of the calcium carbonate composite can be improved.

  In the calcium carbonate composite according to the fifth invention of the present invention, in addition to the third or fourth invention, at least before introducing carbon dioxide gas and introducing carbon dioxide gas, the carbonation rate is at least within 50%. On the other hand, it is produced in a production process further comprising a condensed phosphoric acid addition step of adding condensed phosphoric acid.

  With this configuration, the crystallite size in X-ray diffraction of calcium carbonate constituting the calcium carbonate composite can be made 0.04 μm or less. As a result, the oil absorption of the calcium carbonate composite can be improved.

  In the calcium carbonate composite according to the sixth aspect of the present invention, in addition to the fifth aspect, the condensed phosphoric acid added in the condensed phosphoric acid addition step is calcium hydroxide contained in a calcium hydroxide aqueous suspension. On the other hand, it is 0.1 wt%-5.0 wt%.

  With this configuration, the oil absorption of the calcium carbonate complex can be 15 ml / g or more per gram of phosphorus. In particular, the amount of phosphorus contained in the finally obtained calcium carbonate complex can be relatively reduced, and the amount of oil absorption per gram of phosphorus can be improved.

  In the calcium carbonate composite according to the seventh aspect of the present invention, in addition to any of the third to sixth aspects of the invention, the calcium carbonate aqueous suspension after the carbonation step and the condensed phosphoric acid addition step contains phosphorus. It is manufactured in a manufacturing process further comprising a phosphoric acid addition process for adding an acid.

  With this configuration, a hydroxyapatite layer can be formed.

  In the calcium carbonate complex according to the eighth invention of the present invention, in addition to the seventh invention, a heating step of heating the calcium carbonate aqueous suspension to 60 ° C. to 80 ° C. before the phosphoric acid addition step. It is manufactured in a manufacturing process further comprising

  With this configuration, the formed hydroxyapatite layer can be scaled.

  In the calcium carbonate composite according to the ninth aspect of the present invention, in addition to the seventh aspect, before the phosphoric acid addition step, the calcium carbonate aqueous suspension is dehydrated and dried to be powdered, and then again water-soluble. It is manufactured in a manufacturing process further comprising a re-watering process to obtain a calcium carbonate aqueous suspension.

  With this configuration, the oil absorption of the obtained calcium carbonate composite can be further improved.

  In the calcium carbonate composite according to the tenth aspect of the present invention, in addition to any one of the first to ninth aspects, the hydroxyapatite layer is scaly.

  With this configuration, a large number of fine spaces for storing oil can be formed, and as a total, a large amount of oil can be stored to improve the amount of oil absorption.

  In the calcium carbonate composite according to the eleventh aspect of the present invention, in addition to the tenth aspect, the management temperature of the calcium carbonate aqueous suspension in the phosphoric acid addition step is set to 60 ° C to 80 ° C.

With this configuration, the oil absorption of the calcium carbonate composite can be improved.
(Embodiment 1)

  Embodiment 1 will be described.

(Overview)
The calcium carbonate composite in Embodiment 1 is composed of calcium carbonate and a hydroxyapatite layer formed on the outer periphery of the calcium carbonate. At this time, Ca / P which is the molar ratio of calcium (Ca) and phosphorus (P) is 1.67-20. Furthermore, the oil absorption is 15 ml / g or more per 1 g of phosphorus (P). By having an oil absorption of 15 ml / g or more per gram of phosphorus, the calcium carbonate composite in Embodiment 1 has a high oil adsorbing power after production and reduces oil leakage even when mixed with industrial products. it can. Moreover, when it mixes with cosmetics, the adsorption power of sebum is high and the familiarity to skin becomes high.

(Outline of manufacturing process)
The calcium carbonate composite in the first embodiment is manufactured by the following outline of the manufacturing process. FIG. 1 is a process diagram of a manufacturing process of a calcium carbonate composite according to Embodiment 1 of the present invention. Below, the outline | summary of a manufacturing process is demonstrated using FIG. In addition, the details of each step will be additionally described as necessary when explaining the positive influence on the oil absorption amount of the calcium carbonate composite of the present invention.

  First, a calcium hydroxide aqueous suspension is prepared. As the calcium hydroxide aqueous suspension, a commercially available slaked lime slurry may be used, or quick calcium lime may be mixed with water to obtain a calcium hydroxide aqueous suspension through a digestion step.

  Next, a carbonation step of adding carbon dioxide gas to the calcium hydroxide aqueous suspension is performed. Furthermore, before adding the carbon dioxide gas to the calcium hydroxide aqueous suspension that is the carbonation step, the condensed phosphoric acid is added to start the carbonation step and add condensed phosphoric acid at least at a carbonation rate of 50% or less. An addition step is performed. In FIG. 1, the condensed phosphoric acid addition step is depicted at two locations. This is because the condensed phosphoric acid has a carbonation rate of at least 50% or less before the addition of carbon dioxide gas. It shows that the addition step is performed.

  By this carbonation step and condensed phosphoric acid addition step, calcite-type calcium carbonate particles are generated in the calcium hydroxide aqueous suspension. After the completion of these steps, the suspension is in a state where granular calcite-type calcium carbonate is contained.

  Next, a heating step of heating the aqueous suspension containing the generated calcite-type calcium carbonate (hereinafter referred to as “calcium carbonate”) is performed. Or it replaces with a heating process, and after carrying out dehydration drying of the calcium carbonate water suspension and making it into powder, the re-water-solution process of obtaining the calcium carbonate water suspension which was made water again is implemented.

  A phosphoric acid addition step in which phosphoric acid is added to the calcium carbonate aqueous suspension that has undergone any of the steps is performed. By this phosphoric acid addition step, a hydroxyapatite layer is formed on the outer periphery of the granular calcium carbonate.

  Finally, by dehydrating and drying, a calcium carbonate composite having a hydroxyapatite layer formed on the outer periphery is obtained.

  Next, in the calcium carbonate composite of the present invention, various configurations in which the oil absorption amount per gram of phosphorus is 15 ml / g or more will be described.

  In addition, by having this oil absorption amount of 15 ml / g or more, when a calcium carbonate composite is mixed with an industrial product, the oil adsorption force after manufacture is high and it becomes a level which can reduce the leakage of an oil component. When the oil absorption is lower than this, the oil leakage cannot be sufficiently prevented. Or when a calcium carbonate complex is mixed with cosmetics, the adsorption power of sebum is high and the familiarity to skin becomes high. When the amount of oil absorption is lower than this, the amount of oil absorption is small, so that the adsorptive power to sebum becomes insufficient and the familiarity with the skin becomes weak.

  For this reason, the amount of oil absorption per gram of phosphorus is 15 ml / g or more, and the calcium carbonate composite is mixed with industrial products and cosmetics, thereby exhibiting a higher mixing effect while solving various problems. It is a level that can be done.

(Calcium carbonate crystallite size)
In order to realize the above oil absorption, the crystallite size of calcium carbonate constituting the calcium carbonate composite is preferably 0.04 μm or less as a result of measurement by X-ray diffraction.

  FIG. 2 is a schematic diagram of the calcium carbonate composite according to Embodiment 1 of the present invention. As shown in FIG. 2, the calcium carbonate complex 1 includes granular calcium carbonate 2 and a hydroxyapatite layer 3 formed on the outer periphery.

  The crystallite size of the calcium carbonate 2 shown in FIG. 2 is preferably 0.04 μm or less as a result of measurement by X-ray diffraction. Calcium carbonate is not preferred if the crystallite size measured by X-ray diffraction exceeds 0.04 μm because the amount of oil absorption per gram of phosphorus of the calcium carbonate complex is less than 15 ml / g.

  Here, in order to make the crystallite size of the calcium carbonate 2 in the calcium carbonate complex 1 0.04 μm or less, the calcium hydroxide water in the carbonation step of adding carbon dioxide gas to the calcium hydroxide aqueous suspension described above. The process control temperature, which is the temperature of the suspension, is set to less than 30 ° C.

  If process control temperature is less than 30 degreeC, the crystallite size of the calcium carbonate 2 obtained can be 0.04 micrometer. Conversely, if the process control temperature is 30 ° C. or higher, the crystallite size of the obtained calcium carbonate 2 will exceed 0.04 μm.

  If the crystallite size of the calcium carbonate 2 exceeds 0.04 μm, the oil absorption amount per 1 g of phosphorus of the calcium carbonate complex 1 becomes less than 15 ml / g as will be described later.

(Condensed phosphoric acid addition step)
In the condensed phosphoric acid addition step, the amount of oil absorption per gram of phosphorus of the calcium carbonate complex 1 is increased to 15 ml / g or more by the condensed phosphoric acid addition step of adding condensed phosphoric acid or a salt thereof to the calcium hydroxide aqueous suspension. it can.

  In the condensed phosphoric acid addition step, before adding carbon dioxide gas to the calcium hydroxide aqueous suspension, which is the carbonation step, and at least one in which the carbonation rate of carbonation by adding carbon dioxide gas is within 50%, Condensed phosphoric acid is mixed into the aqueous calcium hydroxide suspension.

  By this condensed phosphoric acid addition step, the optimum calcium carbonate 2 can be obtained for the calcium carbonate complex 1 having an oil absorption amount of 15 ml / g or more per gram of phosphorus. In particular, the process control temperature of the calcium hydroxide aqueous suspension in the carbonation step described above is coupled with the temperature being less than 30 ° C., and the crystallite size of calcium carbonate 2 is 0.04 μm or less by the condensed phosphoric acid addition step. Become.

  As a result, the calcium carbonate complex 1 finally produced in the production process of FIG. 1 can have an oil absorption amount of 15 ml / g or more per gram of phosphorus.

  For example, a calcium carbonate aqueous suspension obtained by carbonation reaction at 15 ° C. as a process control temperature is set to a molar ratio Ca / P of calcium and phosphorus of 3, and after each step of FIG. 1 excluding the condensed phosphoric acid addition step. In the obtained calcium carbonate complex 1, the oil absorption amount per 1 g of phosphorus is 18.4 ml / g (the oil absorption amount of the complex is 185 ml / 100 g).

  On the other hand, before the carbonation step under the same conditions, 2% by weight of sodium metametaphosphate, which is one of condensed phosphoric acids, is added to calcium hydroxide, and the calcium carbonate composite obtained through each step of FIG. The oil absorption per gram of phosphorus is 20.5 ml / g (the oil absorption of the composite is 215 ml / 100 g). That is, by adding the condensed phosphoric acid addition step to the carbonation step, it is possible to further increase the oil absorption amount per gram of phosphorus in the finally produced calcium carbonate composite.

  An example of the condensed phosphoric acid is sodium hexametaphosphate. Further, not the condensed phosphoric acid itself but its salt may be added in the condensed phosphoric acid addition step.

(Addition ratio of condensed phosphoric acid)
In the condensed phosphoric acid addition step, the amount of condensed phosphoric acid or salt thereof added is preferably 0.1 to 5 wt% with respect to calcium hydroxide. If it exceeds 5 wt%, the oil absorption per gram of phosphorus in the composite cannot be 15 ml / g or more. This is probably because some calcium phosphate is generated on the surface of calcium carbonate, so that the coating of the apatite layer with phosphoric acid does not penetrate into the inside.

  Similarly, if the amount of condensed phosphoric acid or salt thereof added is less than 0.1 wt% with respect to calcium hydroxide in the calcium hydroxide aqueous suspension, the effect of adding condensed phosphoric acid Is hardly obtained, and is equivalent to obtaining calcium carbonate 2 only by the carbonation step. In this case, there is a problem that the oil absorption amount of the finally obtained calcium carbonate composite 1 becomes low.

  From the above, the condensed phosphoric acid (and its salt) added in the condensed phosphoric acid addition step is 0.1 wt% to 5.0 wt% with respect to calcium hydroxide in the calcium hydroxide aqueous suspension. It is preferable that the oil absorption amount of the finally obtained calcium carbonate composite 1 is increased to a predetermined level or more.

(Phosphoric acid addition process)
As described in FIG. 1, the calcium carbonate composite 1 of the present invention (the oil absorption amount per gram of phosphorus is 15 ml / g or more) is added with phosphoric acid after the carbonation step and the condensed phosphoric acid addition step. It is manufactured through a phosphoric acid addition step.

  A calcium carbonate aqueous suspension obtained through the carbonation step and the condensed phosphoric acid addition step is obtained. As described above, the calcium carbonate contained in this calcium carbonate aqueous suspension has a crystallite size measured by X-ray diffraction of 0.04 μm or less.

  Phosphoric acid is added to this calcium carbonate aqueous suspension. This is the phosphoric acid addition step. By adding phosphoric acid in this phosphoric acid addition step, the hydroxyapatite layer 3 is formed on the outer periphery of the calcium carbonate 2. The formation of the hydroxyapatite layer 3 can realize the merit of the functional group and the improvement of the oil absorption.

  In the phosphoric acid addition step, the phosphoric acid aqueous solution may be added to the calcium carbonate aqueous suspension while dropping. By the dropwise addition, a hydroxyapatite layer is reliably and accurately formed on the outer periphery of the granular calcium carbonate 2 contained in the calcium carbonate aqueous suspension.

(Heating process)
It is preferable to further include a heating step of heating the calcium carbonate aqueous suspension to 60 ° C. to 80 ° C. before the phosphoric acid addition step.

  Without passing through this heating step, the aqueous calcium carbonate suspension obtained after the condensed phosphoric acid addition step has a temperature of around 30 ° C. because the process control temperature of the carbonation step is less than 30 ° C. . That is, the calcium carbonate aqueous suspension obtained after the condensed phosphoric acid addition step is less than 60 ° C.

However, when the temperature of the calcium carbonate aqueous suspension before the phosphoric acid addition step is less than 60 ° C., coarse calcium hydrogen phosphate (brassite) CaHPO ₄ .2H ₂ O plate crystals are generated. . That is, coarse plate-like particles are newly generated in the liquid instead of the surface of calcium carbonate, so that the hydroxyapatite layer 3 on the outer periphery of the calcium carbonate composite 1 shown in FIG.

  Therefore, the number of hydroxyapatite crystals formed on the outer periphery of the calcium carbonate 2 is reduced.

  As a result, in the calcium carbonate composite finally produced, the oil absorption per gram of phosphorus cannot be 15 ml / g or more.

  On the other hand, when the temperature of the calcium carbonate aqueous suspension before the phosphoric acid addition step (at the time of the phosphoric acid addition step) exceeds 80 ° C., the hydroxyapatite layer 3 formed on the outer periphery of the calcium carbonate 2 Then, the scale-like crystals are reduced. The small number of scaly crystals means that, like the plate-like hydroxyapatite layer 3, the space in which oil can be stored is small as a total volume.

  Also in this case, as a result, in the calcium carbonate composite finally produced, the oil absorption amount per gram of phosphorus cannot be 15 ml / g or more.

  Thus, the calcium carbonate aqueous suspension before the phosphoric acid addition step is preferably 60 ° C to 80 ° C. As described above, since the process control temperature in the carbonation step is less than 30 ° C., the calcium carbonate aqueous suspension after the carbonation step and the condensed phosphoric acid addition step is heated to 60 ° C. to 80 ° C. It is preferred that a warming step is performed.

  A heating process is implement | achieved by connecting a heating apparatus to the container which accommodates calcium carbonate aqueous suspension, and heating the calcium carbonate aqueous suspension in a container to 60 to 80 degreeC. That's fine. Of course, it may be realized by heating by other means.

  It is preferable that 60 ° C. to 80 ° C. heated in the heating step is maintained as a process control temperature in the phosphoric acid addition step.

(Re-watering process)
A phosphoric acid addition process is implemented through a heating process. At this time, the heating step may heat the calcium carbonate aqueous suspension itself obtained through the carbonation step and the condensed phosphoric acid addition step.

  On the other hand, after the calcium carbonate aqueous suspension obtained through the carbonation step and the condensed phosphoric acid addition step is dehydrated and dried to be powdered, the aqueous calcium carbonate suspension is re-watered in the heating step. It may be warmed. The step of re-watering from this dehydration drying is a re-water-solubility step.

  The above-mentioned heating process is given to the calcium carbonate aqueous suspension obtained in this re-watering process. By this heating step, the calcium carbonate aqueous suspension is heated to 60 ° C to 80 ° C. The merit by this heating process is as above-mentioned. By adding phosphoric acid to the calcium carbonate aqueous suspension in this temperature range, the hydroxyapatite layer 3 having scale-like crystals is formed. By forming the hydroxyapatite layer 3 having such scaly crystals, many spaces and enclosed gaps in which oil can be stored are formed. As a result, these spaces and gaps can absorb a large amount of oil, and a calcium carbonate composite having a desired oil absorption per gram of phosphorus of 15 ml / g or more can be realized.

  Here, the calcium carbonate complex produced through the re-watering process has a higher oil absorption than the calcium carbonate complex produced without going through the re-watering process (both heating processes are carried out). realizable.

  For example, the process control temperature of the carbonation step is set to 15 ° C., and the condensed phosphoric acid addition step of adding 2 wt% sodium hexametaphosphate, which is condensed phosphoric acid, with respect to calcium hydroxide is performed before the carbonation step. Thereafter, a calcium carbonate aqueous suspension is obtained through a carbonation step. At this time, the molar ratio Ca / P of calcium and phosphorus is set to 3.0.

  Under these conditions, the amount of oil absorption per gram of phosphorus of the calcium carbonate composite finally produced without undergoing the re-watering step is 20.5 ml / g (the oil absorption of the composite is 215 ml / 100 g).

  On the other hand, the oil absorption per gram of phosphorus of the calcium carbonate composite finally produced through the re-watering step is 23.1 ml / g (the oil absorption of the composite is 242 ml / 100 g). That is, if other conditions are the same, the amount of oil absorption per gram of phosphorus of the calcium carbonate composite produced increases through the re-watering step. For this reason, the amount of oil absorption can be increased by appropriately including the re-watering process in the manufacturing process.

(Crystal shape of the hydroxyapatite layer)
It is preferable that the hydroxyapatite layer 3 on the outer periphery of the calcium carbonate 2 formed in the phosphoric acid addition step is scaly. That is, the hydroxyapatite layer 3 is preferably in a state where scaly crystals are aggregated.

  By being scale-like, the hydroxyapatite layer 3 can form fine spaces in many places. This space is surrounded by a portion of the surroundings with scaly hydroxyapatite crystals, and is not completely closed, but is surrounded. For this reason, it is a form which is easy to store oil.

  Moreover, this fine space is formed in many places. For this reason, in one calcium carbonate complex 1, many enclosed fine spaces are formed. Thus, the enclosed fine space is a large number of spaces that can store oil.

  Since the hydroxyapatite layer 3 is scaly, a large number of spaces where oil can be easily stored are formed. As a result, the calcium carbonate complex 1 having the hydroxyapatite layer 3 can increase the oil absorption amount per gram of phosphorus (15 ml / g or more).

  Further, when the calcium carbonate 2 has a crystallite size measured by X-ray diffraction of 0.04 μm or less, the outer hydroxyapatite layer 3 also easily forms finer scaly crystals. In addition, since the crystallite size of the calcium carbonate 2 is small, the surface area (including the surface area formed by the scale-like hydroxyapatite layer 3) and the scale-like hydroxyapatite with respect to the volume of the calcium carbonate complex 1 The total volume of the space for storing the oil component formed by the layer 3 becomes relatively large.

  Since the surface area and the oil storage space ratio with respect to the volume of the calcium carbonate composite 1 are high, the oil absorption amount of the calcium carbonate composite 1 to be manufactured is naturally high.

(Molar ratio)
It is also preferable that the calcium carbonate complex has a calcium / phosphorus (Ca / P) molar ratio of 1.67 to 20. If Ca / P is 1.67 or more, the oil absorption amount per gram of phosphorus of the calcium carbonate complex can be secured at 15 ml / g or more, but if it is less than 1.67, it is preferable because coarse particles of brushite are mixed. Absent.

  FIG. 3 is a graph showing the relationship between Ca / P and the oil absorption of the calcium carbonate complex. When Ca / P is in the range of 1.67 to 20, when the Ca / P molar ratio increases (that is, when the amount of phosphorus decreases), the oil absorption of the calcium carbonate complex decreases.

  On the other hand, when the ratio of Ca / P exceeds 20, the oil absorption amount of the calcium carbonate composite tends to be constant at about 120 ml / 100 g. For this reason, if the amount of phosphorus is further reduced, there is no effect of phosphorus in that region, so the apparent oil absorption per gram of phosphorus increases, but the oil absorption of the complex does not increase, so Ca / P itself Makes no sense.

  From these, it is also suitable that the molar ratio of calcium / phosphorus (Ca / P) of the calcium carbonate complex is 1.67 to 20.

  By setting the molar ratio within a predetermined range, it is possible to realize a calcium carbonate complex having an oil absorption amount of 15 ml / g or more per 1 g of phosphorus, which cannot be realized by the prior art in consideration of cost and environmental load. .

  The calcium carbonate composite having a hydroxyapatite layer in the prior art has not sufficiently considered the crystallite size of calcium carbonate, the shape of the hydroxyapatite layer, the relationship between calcium carbonate and the hydroxyapatite layer, and the like. It was. There was no disclosure of the shape and configuration of these, and the disclosure of the process for realizing it. For this reason, the calcium carbonate composite of the prior art has either no consideration for the oil absorption amount or is insufficient.

  On the other hand, the calcium carbonate composite of the present invention has an oil absorption amount that is sufficient when added to industrial products and cosmetics due to the shape, configuration, relationship, and the like as described above. 15 ml / g or more can be realized. In particular, since the amount of oil absorption per unit weight of phosphorus, which is expensive as a substance and important for the global environment, can be improved, cost and environmental load can be suppressed.

  (Embodiment 2)

  Next, a second embodiment will be described. In the second embodiment, examples and the like by the inventors in the calcium carbonate composite described in the first embodiment will be described.

  First, each experiment (crystallite size, the amount of oil absorption of the calcium carbonate complex, the amount of oil absorption per gram of phosphorus) for confirming the results of the manufactured examples will be described.

(Method for confirming crystallite size)
In Embodiment 1, it has been described that the crystallite size of calcium carbonate of the calcium carbonate complex is preferably 0.04 μm or less after being measured by X-ray diffraction. As described in Embodiment 1, calcium carbonate is obtained in a carbonation step of adding carbon dioxide gas to a calcium hydroxide aqueous suspension. At this time, the crystallite size of calcium carbonate can be made 0.04 μm or less by setting the process control temperature, which is the temperature of the calcium hydroxide aqueous suspension when adding carbon dioxide gas, to less than 30 ° C.

  The crystallite size of this calcium carbonate (which is calcite-type calcium carbonate) was measured using JADE by (104) plane reflection. The measurement conditions using the Rigaku X-ray diffractometer MultiFlex are shown below.

Tube: Cu
Monochromatic: Monochromator (Kα line)
Voltage: 40 kV
Current: 30mA
(104) Surface reflection: 10000 counts or more of peak top

(Measurement method of oil absorption of calcium carbonate complex)
The amount of oil absorption of the calcium carbonate composite is an important factor of the calcium carbonate composite of the present invention. This oil absorption was measured under the following conditions.

  According to JIS K5101, 2 g of sample was precisely weighed, the amount of boiled linseed oil added was read to two decimal places, and the amount of oil absorption in 100 g of sample was calculated.

(Oil absorption per gram of phosphorus of calcium carbonate complex)
The calcium carbonate composite of the present invention realizes an increase in oil absorption per gram of phosphorus (15 ml / g or more), which is an expensive and rare substance. For this reason, it is necessary to measure the amount of oil absorption per gram of phosphorus, and the measurement was performed under the following conditions.

  After the reaction with phosphoric acid, the absence of phosphorus in the filtrate was confirmed with an ICP emission spectrometer, the weight percent of phosphorus in the complex was calculated from the amount of phosphorus used, and the oil absorption of the complex was calculated. Determined by dividing by the weight percent of phosphorus.

  Hereinafter, the Example etc. which actually manufactured the calcium carbonate composite demonstrated in Embodiment 1 while changing conditions are demonstrated. In any case, in the first embodiment, while conducting each experiment according to the conditions in the case of obtaining a calcium carbonate composite having a high oil absorption amount, the examples were manufactured and confirmed.

  (Experiment 1: Confirmation of difference due to crystallite size of calcium carbonate)

Example 1
(1) Production of calcium hydroxide aqueous suspension Water was added to slaked lime made in-house to produce a calcium hydroxide aqueous suspension.
(2) Condensed phosphoric acid addition step

  Subsequently, the condensed phosphoric acid addition process which adds 2 weight% sodium hexametaphosphate with respect to calcium hydroxide to this calcium hydroxide aqueous suspension was implemented. Thus, 400 g of a 6 wt% calcium hydroxide aqueous suspension with a process control temperature of the calcium hydroxide aqueous suspension of 15 ° C. was produced.

(3) Carbonation step Next, carbon dioxide gas was introduced into this calcium hydroxide aqueous suspension, and a carbonation step in 40 minutes was carried out. By this carbonation step, a calcium carbonate aqueous suspension was obtained.

(4) Warming process The heating process which heats the obtained calcium carbonate aqueous suspension to 65 degreeC was implemented. The temperature of the calcium carbonate aqueous suspension produced | generated at the carbonation process was adjusted to 65 degreeC by the heating process.

(5) Phosphoric acid addition step 300 ml of 85% phosphoric acid diluted so that Ca / P is 3, including the phosphorus content of sodium hexametaphosphate added during the carbonation reaction, is added over 30 minutes using a dropping pump. Added. The temperature of the calcium carbonate aqueous suspension during the addition of phosphoric acid was maintained at 65 ° C. After completion of the addition, it was dehydrated and dried to obtain a white powder.

(Confirmation result of Example 1)
It was confirmed by X-ray diffraction that the obtained white powder was a calcium carbonate composite of calcium carbonate and a hydroxyapatite layer. The confirmation by X-ray diffraction is as shown in FIG. FIG. 4 is a graph showing the results of confirmation by X-ray diffraction of the obtained powder in Embodiment 2 of the present invention.

  It was confirmed by the scanning electron microscope that a scaly hydroxyapatite layer was formed on the surface as shown in FIGS. FIG. 5 is an electron micrograph showing a scaly hydroxyapatite layer in the example of Embodiment 2 of the present invention. FIG. 6 is an electron micrograph showing a scaly hydroxyapatite layer in the example of Embodiment 2 of the present invention.

  In the calcium carbonate composite produced in Example 1, as shown in the electron micrographs of FIGS. 5 and 6, the hydroxyapatite layer formed on the outer periphery of the calcium carbonate has a scaly shape. As described in Embodiment 1, the scale-like shape increases the total volume of the space for storing oil and increases the oil absorption.

  The oil absorption of the calcium carbonate composite of Example 1 was measured and found to be 215 ml / 100 g. The value obtained by calculating the weight% of phosphorus in the complex from the amount of phosphorus used and dividing the oil absorption by the weight% of phosphorus, that is, the oil absorption per gram of phosphorus of the complex was 20.5 ml. As a result, it was confirmed that the oil absorption amount per gram of phosphorus was 15 ml / g or more.

  In addition, when the filtrate at the time of dehydration after adding phosphoric acid was collected and the concentration of phosphorus in the filtrate was measured, there was no phosphorus in the filtrate, and most of the used phosphorus was contained in the complex. Was confirmed.

  The crystallite size of the calcium carbonate after the carbonation reaction was again subjected to the carbonation reaction under the same conditions, and the dehydrated and dried calcium carbonate was measured. As a result, the crystallite size was 0.0278 μm. This is a result of measurement by X-ray diffraction.

  As will be described later, for Examples 1 to 3 and Comparative Example 1 related to Experiment 1, Table 1 shows a list of results and the like.

(Example 2)
(Manufacturing process)
The calcium carbonate composite of Example 2 had the same conditions as Example 1 except that the process control temperature of the carbonation process was 12.5 ° C. (temperature of the calcium hydroxide aqueous suspension before the carbonation process). Produced in the process.

(Confirmation result of Example 2)
From the X-ray diffraction shown in FIG. 4 and the observation with the scanning electron microscope of FIGS. 5 and 6, it was confirmed to be a calcium carbonate composite composed of calcium carbonate and a hydroxyapatite layer. Moreover, it was confirmed from the electron micrographs of FIGS. 5 and 6 that the hydroxyapatite layer is scaly.

  The oil absorption was 208 ml / 100 g, and the oil absorption of 1 g of phosphorus in the calcium carbonate complex was 19.8 ml / g. The crystallite size of calcium carbonate was 0.0208 μm.

  As in Example 1, when the crystallite size of calcium carbonate is 0.04 μm or less, the oil absorption amount of the calcium carbonate complex and the oil absorption amount per gram of phosphorus are sufficiently higher than the standard values. It was confirmed that it is optimal for mixing into products.

    Example 3

(Manufacturing process)
The calcium carbonate composite of Example 3 has the same conditions and steps as in Example 1 except that the process control temperature of the carbonation step (temperature of the calcium hydroxide aqueous suspension before the carbonation step) was 25 ° C. Produced.

(Confirmation result of Example 3)
From the X-ray diffraction shown in FIG. 4 and the observation with the scanning electron microscope of FIGS. 5 and 6, it was confirmed to be a calcium carbonate composite composed of calcium carbonate and a hydroxyapatite layer. Further, from the electron micrographs of FIGS. 5 and 6, it was confirmed that the hydroxyapatite layer was scaly.

  The oil absorption of the calcium carbonate composite was 185 ml / 100 g, and the oil absorption of 1 g of phosphorus was 17.7 ml / g. The crystallite size of calcium carbonate was 0.0353 μm.

  As in Example 1, when the crystallite size of calcium carbonate is 0.04 μm or less, the oil absorption amount of the calcium carbonate complex and the oil absorption amount per gram of phosphorus are sufficiently higher than the standard values. It was confirmed that it is optimal for mixing into products.

    (Comparative Example 1)

(Manufacturing process)
It was manufactured under the same conditions and steps as in Example 1 except that the process control temperature of the carbonation step (the temperature of the calcium hydroxide aqueous suspension before the carbonation step) was 30 ° C.

(Confirmation result of Comparative Example 1)
From the X-ray diffraction, it was confirmed that a brushite peak appeared in addition to calcium carbonate and hydroxyapatite, and the calcium carbonate composite was not sufficient.

  Furthermore, in the scanning electron microscope shown in FIG. 7, smooth coarse particles having a surface of 10 μm or more were observed. FIG. 7 is an electron micrograph of the powder obtained in the comparative example in the second embodiment. It was also confirmed from the electron micrograph that the formation of a complex of calcium carbonate and hydroxyapatite was inhibited.

  The oil absorption amount of Comparative Example 1 was 80 ml / 100 g, and the oil absorption amount per gram of phosphorus was 7.6 ml / g. The crystallite size of calcium carbonate was 0.0402 μm.

  By including the coarse particles of the plate-like brushite, the volume of the space for storing oil is reduced. Moreover, the crystallite size of calcium carbonate exceeds 0.04 μm, and the total surface area of the calcium carbonate volume and the total volume of the space for storing the oil content are relatively smaller than those of Examples 1 to 3. As a result, the oil absorption amount of Comparative Example 1 is at an insufficient level.

  From the results of Examples 1 to 3, the crystallite size in the X-ray diffraction of the calcium carbonate constituting the calcium carbonate composite is 0.04 μm or less by setting the process control temperature in the carbonation step to be less than 30 ° C. It becomes. By combining the conditions in the other steps with this (the hydroxyapatite layer becomes scaly), a calcium carbonate complex that achieves a high oil absorption amount of 15 ml / g or more per gram of phosphorus can be obtained. Was confirmed from Experiment 1.

  That is, from Examples 1 to 3 and Comparative Example 1, when the crystallite size of calcium carbonate exceeds 0.04 μm, the oil absorption amount of the calcium carbonate composite is reduced, and the oil absorption amount per gram of phosphorus is also reduced. It was confirmed that

  (Experiment 2: Amount of condensed phosphoric acid added in the condensed phosphoric acid step)

    (Example 4)

(Manufacturing process)
Before the carbonation step, 0.1 wt% of sodium metametaphosphate, which is condensed phosphoric acid, was added to the calcium hydroxide aqueous suspension with respect to calcium hydroxide. That is, in the condensed phosphoric acid addition step, 0.1 wt% condensed phosphoric acid was added to calcium hydroxide. Except for this, the calcium carbonate composite of Example 4 was produced under the same conditions as in Example 1.

(Confirmation result of Example 4)
In the calcium carbonate composite of Example 4, the total oil absorption was 188 ml / 100 g, and the oil absorption per gram of the calcium carbonate composite was 18.7 ml / g.

  In the condensed phosphoric acid addition step, 0.1 wt% condensed phosphoric acid is added to calcium hydroxide, so that the oil absorption amount per 1 g of phosphorus sufficiently exceeds the standard value of 15 ml / g. confirmed.

  In addition, in the calcium carbonate composite of the present invention, an oil absorption amount exceeding the standard value of 15 ml / g can be obtained even when condensed phosphoric acid is not added in the condensed phosphoric acid addition step. For example, it was confirmed that the calcium carbonate composite produced by the same manufacturing method as in Example 1 with the addition amount of condensed phosphoric acid being zero had an oil absorption of 18.4 ml / g per gram of phosphorus. In addition, by adding condensed phosphoric acid, the oil absorption per gram of phosphorus can be further increased as in Examples 4 to 5.

    (Example 5)

(Manufacturing process)
Before the carbonation step, 0.5 wt% of sodium metametaphosphate, which is condensed phosphoric acid, was added to the calcium hydroxide aqueous suspension with respect to calcium hydroxide. That is, in the condensed phosphoric acid addition step, 0.5 wt% condensed phosphoric acid was added to calcium hydroxide. Except for this, a calcium carbonate composite was produced under the same conditions as in Example 1.

(Confirmation result of Example 5)
The oil absorption amount of the whole calcium carbonate composite of Example 5 was 205 ml / 100 g, and the oil absorption amount per 1 g of phosphorus was 20.4 ml / g.

  In the condensed phosphoric acid addition step, 0.5 wt% of condensed phosphoric acid is added to calcium hydroxide, so that the oil absorption amount per 1 g of phosphorus sufficiently exceeds the standard value of 15 ml / g. confirmed.

    (Example 6)

(Manufacturing process)
Before the carbonation step, 5 wt% of sodium metametaphosphate, which is condensed phosphoric acid, was added to the calcium hydroxide aqueous suspension with respect to the calcium hydroxide. That is, in the condensed phosphoric acid addition step, 5 wt% condensed phosphoric acid was added to calcium hydroxide. Except for this, a calcium carbonate composite was produced under the same conditions as in Example 1.

(Confirmation result of Example 6)
The oil absorption amount of the whole calcium carbonate composite of Example 6 was 168 ml / 100 g, and the oil absorption amount per 1 g of phosphorus was 15.0 ml / g.

  In the condensed phosphoric acid addition step, it was confirmed that the amount of oil absorption per gram of phosphorus sufficiently exceeded the standard value of 15 ml / g by adding 5 wt% condensed phosphoric acid to calcium hydroxide. It was.

    (Comparative Example 2)

(Manufacturing process)
Before the carbonation step, 10 wt% of sodium metametaphosphate, which is condensed phosphoric acid, was added to the calcium hydroxide aqueous suspension with respect to calcium hydroxide. That is, in the condensed phosphoric acid addition step, 10 wt% condensed phosphoric acid was added to calcium hydroxide. Except for this, a calcium carbonate composite was produced under the same conditions as in Example 1.

(Confirmation result of Comparative Example 2)
The oil absorption amount of the whole calcium carbonate composite of Comparative Example 2 was 70 ml / 100 g, and the oil absorption amount per gram of phosphorus was 5.66 ml / g.

  When the condensed phosphoric acid added in the condensed phosphoric acid addition step is 0.1 wt% to 5.0 wt% with respect to calcium hydroxide, the oil absorption of the produced calcium carbonate composite is 1 g of phosphorus. It was confirmed in these experiments 2 that the standard of 15 ml / g or more was sufficiently exceeded. On the other hand, when condensed phosphoric acid exceeded 5 wt%, it was confirmed that the amount of oil absorption of the calcium carbonate composite produced decreases and becomes insufficient.

  Table 2 shows the experimental results obtained by adding Example 1 to Examples 4 to 6 and combining it with Comparative Example 2.

  (Experiment 3: Timing of condensed phosphoric acid process)

    (Example 7)

(Manufacturing process)
Addition of sodium hexametaphosphate, which is condensed phosphoric acid, was carried out at a carbonation rate of 28% (50% or less) in the carbonation step. Except for this, a calcium carbonate composite was produced under the same conditions as in Example 1.

(Confirmation result of Example 7)
The oil absorption of the calcium carbonate composite of Example 7 was 200 ml / 100 g, and the oil absorption per 1 g of phosphorus was 19.2 ml / g. The calcium carbonate composite produced by carrying out the condensed phosphoric acid addition step with a carbonation rate of 50% or less has an oil absorption amount of 15 ml / g or more per gram of phosphorus, which is a reference value, and has a high result. This was confirmed from Example 7.

    (Example 8)

(Manufacturing process)
Addition of sodium hexametaphosphate, which is a condensed phosphoric acid, was carried out at a carbonation rate of 45.2% (50% or less) in the carbonation step. Except for this, a calcium carbonate composite was produced under the same conditions as in Example 1.

(Confirmation result of Example 8)
The oil absorption of the calcium carbonate composite of Example 8 was 180 ml / 100 g, and the oil absorption per gram of phosphorus was 17.3 ml / g. The calcium carbonate composite produced by carrying out the condensed phosphoric acid addition step with a carbonation rate of 50% or less has an oil absorption amount of 15 ml / g or more per gram of phosphorus, which is a reference value, and has a high result. This was confirmed from Example 8.

    (Comparative Example 3)

(Manufacturing process)
Addition of sodium hexametaphosphate, which is a condensed phosphoric acid, was carried out at a carbonation rate of 53.4% (50% or more) in the carbonation step. Except for this, a calcium carbonate composite was produced under the same conditions as in Example 1.

(Confirmation result of Comparative Example 3)
The oil absorption of the calcium carbonate composite of Comparative Example 3 was 115 ml / 100 g, and the oil absorption per 1 g of phosphorus was 11.0 ml / g. It was below the standard value of 15 ml / g of oil absorption per gram of phosphorus, which was confirmed to be insufficient.

  About Example 7-Comparative Example 3, including Example 1, the result is shown in Table 3. From the results of Table 3, it was confirmed that the condensed phosphoric acid addition step is preferably performed at least one of the carbonation rate before and at the carbonation step is 50% or less.

(Experiment 4: Process control temperature of phosphoric acid addition process)
In Experiment 4, the difference in the oil absorption amount of the obtained calcium carbonate composite was confirmed by the difference in the process control temperature of the calcium carbonate aqueous suspension in the phosphoric acid addition step.

    Example 9

(Manufacturing process)
The addition of phosphoric acid in the phosphoric acid addition step maintains a process control temperature at 60 ° C., which is the temperature of the calcium carbonate aqueous suspension to which phosphoric acid is added (obtained through the carbonation step and the condensed phosphoric acid step). ,It was conducted. Except for this, a calcium carbonate composite was produced under the same conditions as in Example 1.

(Confirmation result of Example 9)
The oil absorption of the calcium carbonate composite of Example 9 was 243 ml / 100 g, and the oil absorption per gram of phosphorus was 23.1 ml / g. When the process control temperature of the calcium carbonate aqueous suspension when the phosphoric acid addition step is performed is in the range of 60 ° C. to 80 ° C., the oil absorption per gram of phosphorus, which is the reference value, is 15 ml / g or more. Thus, it was confirmed from Example 9 that a high result was shown.

    (Example 10)

(Manufacturing process)
The addition of phosphoric acid in the phosphoric acid addition step maintains a process control temperature at 70 ° C., which is the temperature of the calcium carbonate aqueous suspension to which phosphoric acid is added (obtained through the carbonation step and the condensed phosphoric acid step). ,It was conducted. Except for this, a calcium carbonate composite was produced under the same conditions as in Example 1.

(Confirmation result of Example 10)
The oil absorption of the calcium carbonate composite of Example 10 was 223 ml / 100 g, and the oil absorption per 1 g of phosphorus was 21.3 ml / g. When the process control temperature of the calcium carbonate aqueous suspension when the phosphoric acid addition step is performed is 70 ° C. within the range of 60 ° C. to 80 ° C., the oil absorption amount per 1 g of phosphorus as a reference value is 15 ml / g It was confirmed from Example 10 that it was the above and showed a high result.

    (Example 11)

(Manufacturing process)
The addition of phosphoric acid in the phosphoric acid addition process is maintained at a process control temperature of 80 ° C., which is the temperature of the calcium carbonate aqueous suspension to which phosphoric acid is added (obtained through the carbonation process and the condensed phosphoric acid process). ,It was conducted. Except for this, a calcium carbonate composite was produced under the same conditions as in Example 1.

(Confirmation result of Example 11)
The oil absorption of the calcium carbonate composite of Example 11 was 179 ml / 100 g, and the oil absorption per 1 g of phosphorus was 17.1 ml / g. When the process control temperature of the calcium carbonate aqueous suspension when the phosphoric acid addition step is performed is 80 ° C. within the range of 60 ° C. to 80 ° C., the oil absorption amount per 1 g of phosphorus as a reference value is 15 ml / g. It was confirmed from Example 11 that it was the above and showed a high result.

    (Comparative Example 4)

(Manufacturing process)
The addition of phosphoric acid in the phosphoric acid addition step maintains a process control temperature at 30 ° C., which is the temperature of the calcium carbonate aqueous suspension to which phosphoric acid is added (obtained through the carbonation step and the condensed phosphoric acid step). ,It was conducted. Except for this, a calcium carbonate composite was produced under the same conditions as in Example 1.

(Confirmation result of Comparative Example 4)
The oil absorption of the calcium carbonate composite of Comparative Example 4 was 110 ml / 100 g, and the oil absorption per 1 g of phosphorus was 10.5 ml / g. When the process control temperature of the calcium carbonate aqueous suspension when the phosphoric acid addition step is performed is 30 ° C., which is outside the range of 60 ° C. to 80 ° C., the oil absorption amount per 1 g of phosphorus which is the reference value is 15 ml / g A result less than 1 was confirmed from Comparative Example 4.

    (Comparative Example 5)

(Manufacturing process)
The addition of phosphoric acid in the phosphoric acid addition step maintains the process control temperature at 55 ° C., which is the temperature of the calcium carbonate aqueous suspension to which phosphoric acid is added (obtained through the carbonation step and the condensed phosphoric acid step). ,It was conducted. Except for this, a calcium carbonate composite was produced under the same conditions as in Example 1.

(Confirmation result of Comparative Example 5)
The oil absorption of the calcium carbonate composite of Comparative Example 5 was 102 ml / 100 g, and the oil absorption per gram of phosphorus was 9.7 ml / g. When the process control temperature of the calcium carbonate aqueous suspension when the phosphoric acid addition step is performed is 55 ° C. outside the range of 60 ° C. to 80 ° C., the oil absorption amount per 1 g of phosphorus, which is the reference value, is 15 ml / g. A result of less than 5 was confirmed from Comparative Example 5.

    (Comparative Example 6)

(Manufacturing process)
The addition of phosphoric acid in the phosphoric acid addition step maintains a process control temperature at 90 ° C., which is the temperature of the calcium carbonate aqueous suspension to which phosphoric acid is added (obtained through the carbonation step and the condensed phosphoric acid step). ,It was conducted. Except for this, a calcium carbonate composite was produced under the same conditions as in Example 1.

(Confirmation result of Comparative Example 6)
The oil absorption of the calcium carbonate composite of Comparative Example 6 was 120 ml / 100 g, and the oil absorption per gram of phosphorus was 11.5 ml / g. When the process control temperature of the calcium carbonate aqueous suspension when the phosphoric acid addition step is performed is 90 ° C., which is outside the range of 60 ° C. to 80 ° C., the oil absorption amount per 1 g of phosphorus, which is the reference value, is 15 ml / g. A result of less than 1 was confirmed from Comparative Example 6.

  The results of Example 9 to Comparative Example 6 are shown in Table 4.

  As is clear from the results in Table 4, the process control temperature of the calcium carbonate aqueous suspension in the phosphoric acid addition step of adding phosphoric acid to the calcium carbonate aqueous suspension is preferably 60 ° C to 80 ° C. Was confirmed. In other words, it was confirmed that a heating step of heating the calcium carbonate aqueous suspension obtained after the carbonation step and the condensed phosphoric acid addition step to 60 ° C. to 80 ° C. is preferably performed.

  (Experiment 5: Origin of calcium hydroxide aqueous suspension)

    (Example 12)

(Manufacturing process)
A calcium hydroxide aqueous suspension prepared by adding 30 g of quicklime produced in-house to 400 g of water at 50 ° C. was adjusted in concentration and weight, and the carbonation reaction was performed in the same scale as in Example 1 as in Example 1. And the reaction with phosphoric acid was carried out to produce the calcium carbonate composite of Example 12.

(Confirmation result of Example 12)
The oil absorption of the calcium carbonate composite of Example 12 was 205 ml / 100 g, and the oil absorption per 1 g of phosphorus was 19.6 ml / g. Together with Example 1, the results of Example 12 are shown in Table 5.

  From the results of Example 12 and Example 1 in Table 5, the calcium hydroxide aqueous suspension is usually adjusted with slaked lime, but there is no problem even if the calcium hydroxide aqueous suspension is adjusted from quick lime. Was confirmed.

(Experiment 6: Confirmation of the difference in the re-watering process)
In Experiment 6, the difference in the oil absorption amount of the obtained calcium carbonate composite was confirmed through the re-watering process.

    (Example 13)

(Manufacturing process)
The carbonic acid solution of Example 13 was added to the calcium carbonate aqueous suspension obtained through the carbonation step and the condensed phosphoric acid addition step under the same conditions as in Example 1 by dehydrating and drying to re-water the solution. A calcium complex was produced.

  In the re-watering step, white powder mainly containing calcium carbonate is obtained by dehydration and drying. This white powder was lightly crushed and passed through a 0.3 mm sieve, and water was added to make the total amount 400 g to prepare a calcium carbonate aqueous suspension.

  The phosphoric acid addition step was carried out in the same manner as in Example 1 except that the calcium carbonate aqueous suspension obtained through this re-watering step was heated to 65 ° C. to make Ca / P 1.67. It was.

(Confirmation result of Example 13)
The oil absorption of the calcium carbonate composite of Example 13 was 271 ml / 100 g, and the oil absorption per 1 g of phosphorus was 15.1 ml / g. Even after the re-watering step, it was confirmed that the oil absorption amount of the produced calcium carbonate composite exceeded the reference value when other conditions were satisfied.

    (Example 14)

(Manufacturing process)
Example 14 was produced under the same conditions as Example 13 except that the reaction with phosphoric acid was 1.9 Ca / P.

(Confirmation result of Example 14)
The oil absorption of the calcium carbonate composite of Example 14 was 296 ml / 100 g, and the oil absorption per 1 g of phosphorus was 20.4 ml / g.

    (Example 15)

(Manufacturing process)
Example 15 was produced under the same conditions as Example 13 except that the reaction with phosphoric acid was changed to Ca / P of 2.4.

(Confirmation result of Example 15)
The oil absorption of the calcium carbonate composite of Example 15 was 263 ml / 100 g, and the oil absorption per 1 g of phosphorus was 17.3 ml / g.

    (Example 16)

(Manufacturing process)
Example 16 was produced under the same conditions as Example 13 except that the reaction with phosphoric acid was changed to 3 for Ca / P.

(Confirmation result of Example 16)
The oil absorption of the calcium carbonate composite of Example 16 was 242 ml / 100 g, and the oil absorption per 1 g of phosphorus was 23.1 ml / g. As can be seen from the comparison with Example 1, in Example 1 in which the rewatering process was not performed and in Example 16 in which the rewatering process was performed (processes and conditions other than the rewatering process were the same), It was confirmed that the oil absorption amount of Example 16 was higher than the oil absorption amount of Example 1. That is, it was confirmed that if the other conditions are the same, it is suitable to improve the oil absorption amount through the re-watering step.

    (Example 17)

(Manufacturing process)
Example 17 was produced under the same conditions as Example 13 except that the reaction with phosphoric acid was changed to Ca / P of 3.8.

(Confirmation result of Example 17)
The oil absorption of the calcium carbonate composite of Example 17 was 187 ml / 100 g, and the oil absorption per 1 g of phosphorus was 23.4 ml / g.

    (Example 18)

(Manufacturing process)
Example 18 was produced under the same conditions as Example 13 except that the reaction with phosphoric acid was changed to Ca / P of 4.6.

(Confirmation result of Example 18)
The oil absorption of the calcium carbonate composite of Example 18 was 185 ml / 100 g, and the oil absorption per 1 g of phosphorus was 28.6 ml / g.

    (Example 19)

(Manufacturing process)
Example 19 was produced under the same conditions as Example 13 except that the reaction with phosphoric acid was changed to 8.7 for Ca / P.

(Confirmation result of Example 19)
The oil absorption of the calcium carbonate composite of Example 19 was 166 ml / 100 g, and the oil absorption per 1 g of phosphorus was 48.0 ml / g.

    (Example 20)

(Manufacturing process)
Example 20 was produced under the same conditions as in Example 13 except that the reaction with phosphoric acid was changed to 12 for Ca / P.

(Confirmation result of Example 20)
The oil absorption of the calcium carbonate composite of Example 20 was 140 ml / 100 g, and the oil absorption per gram of phosphorus was 56.7 ml / g.

    (Example 21)

(Manufacturing process)
Example 21 was produced under the same conditions as Example 13 except that the reaction with phosphoric acid was changed to Ca / P = 20.

(Confirmation result of Example 21)
The oil absorption of the calcium carbonate composite of Example 21 was 150 ml / 100 g, and the oil absorption per gram of phosphorus was 102 ml / g.

    (Comparative Example 7)

(Manufacturing process)
Comparative Example 7 was produced under the same conditions as Example 13 except that the reaction with phosphoric acid was changed to Ca / P of 1.5.

(Confirmation result of Comparative Example 7)
The oil absorption of the calcium carbonate composite of Comparative Example 7 was 261 ml / 100 g, and the oil absorption per 1 g of phosphorus was 10.5 ml / g. In Comparative Example 7, even when the water-resolving step is performed, if Ca / P, which is the molar ratio of calcium and phosphorus, is not included in 1.67 to 20, the oil absorption amount per 1 g of phosphorus is the reference value. It was confirmed that it did not reach.

    (Comparative Example 8)

(Manufacturing process)
Comparative Example 8 was produced under the same conditions as Example 14 except that the reaction with phosphoric acid was changed to 28 for Ca / P.

(Confirmation result of Comparative Example 8)
The oil absorption of the calcium carbonate composite of Comparative Example 8 was 120 ml / 100 g, and the oil absorption per gram of phosphorus was 112 ml / g. In Comparative Example 8, even when the water re-watering step has been performed, if Ca / P, which is the molar ratio of calcium and phosphorus, is not included in 1.67 to 20 as in Comparative Example 7, Although the amount of oil absorption exceeds the reference value, the amount of oil absorption of the composite itself decreases, which is not preferable.

  The results of Example 13 to Comparative Example 8 are shown in Table 6.

  As shown in Table 6, in the reaction with phosphoric acid, it was confirmed that the molar ratio of calcium to phosphorus was between 1.67 and 20 in terms of Ca / P.

  In addition, according to Example 1 and Example 17, the calcium carbonate composite satisfying the criteria of the present invention is obtained through a re-watering step in which the calcium carbonate aqueous suspension is dehydrated and dried to be powdered and then re-watered. It was also confirmed that it was obtained. In particular, under the same conditions, it was confirmed that the amount of oil absorption was improved through the re-watering step.

  In addition, the calcium carbonate composite demonstrated by Embodiment 1-2 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 Calcium carbonate 3 Hydroxyapatite layer

Claims (9)

With calcium carbonate,
A hydroxyapatite layer formed on the outer periphery of the calcium carbonate,
The molar ratio of calcium and phosphorus (Ca / P) is 1.67-20,
Oil absorption state, and are more phosphorus 1g per 15ml / g,
The calcium carbonate has a crystallite size measured by X-ray diffraction of 0.04 μm or less,
The hydroxyapatite layer is a scale-like calcium carbonate composite. A composition to which the calcium carbonate complex according to claim 1 is added. The composition according to claim 2, wherein the composition is any one of a pigment, a cosmetic, a beauty agent, a dentifrice, a paint, an abrasive and a polishing aid. With calcium carbonate,
A method for producing a calcium carbonate composite comprising a hydroxyapatite layer formed on the outer periphery of the calcium carbonate,
A carbonation step of adding carbon dioxide gas to a calcium hydroxide aqueous suspension to form the calcium carbonate;
A condensed phosphoric acid addition step of adding condensed phosphoric acid before introducing the carbon dioxide gas and at least one of introducing the carbon dioxide gas and having a carbonation rate within 50%;
A phosphoric acid addition step of adding phosphoric acid to the aqueous calcium carbonate suspension after the carbonation step and after the condensed phosphoric acid addition step,
The calcium carbonate complex is
The molar ratio of calcium and phosphorus (Ca / P) is 1.67-20,
Oil absorption is 15 ml / g or more per gram of phosphorus,
The calcium carbonate has a crystallite size measured by X-ray diffraction of 0.04 μm or less,
The method for producing a calcium carbonate complex, wherein the hydroxyapatite layer is scaly. The manufacturing method of the calcium carbonate complex of Claim 4 whose process control temperature of the said calcium hydroxide suspension is less than 30 degreeC at the time of adding the said carbon dioxide gas to the said calcium hydroxide aqueous suspension . The condensed phosphoric acid added in the condensed phosphoric acid addition step, to calcium hydroxide contained in the calcium hydroxide aqueous suspension is 0.1 wt% 5.0 wt%, claim 4 or 6. A method for producing a calcium carbonate composite according to 5 . Before the phosphoric acid addition step, the further Ru comprising a heating step of heating the calcium water suspension carbonate 60 ° C. to 80 ° C., the production of calcium carbonate complex according to any of claims 4 6 Method. Before the phosphoric acid addition step, after the calcium carbonate aqueous suspension is pulverized by dehydration and drying, further comprising a re-aqueous process for the calcium carbonate aqueous suspension obtained by water again, from the claims 4 8. The method for producing a calcium carbonate composite according to any one of 7 above . The manufacturing method of the complex of the calcium carbonate complex in any one of Claim 4 to 8 which makes the management temperature of the said calcium carbonate aqueous suspension in the said phosphoric acid addition process 60-60 degreeC.