JPS5964527A - Amorphous calcium carbonate, its preparation and material for releasing substance adsorbed to it at proper rate - Google Patents

Abstract

PURPOSE:To obtain stable amorphous calcium carbonate and a material having a controlled volatilization speed for various kinds of volatile substances using it as a base material, by carbonating a Ca compd. in or org. medium. CONSTITUTION:A calcium compound such as calcium carbonate, calcium hydroxide, etc. as a raw material is subjected to carbonation reaction (e.g., carried out by using carbon dioxide or carbonate compound) in an organic medium system (e.g., <=4C mono-, bi-, or trihydric alcohol, etc.), to give amorphous calcium carbonate having 1.6-2.5 true specific gravity, 1.45-1.57 refractive index, 20- 60DELTAm<2>/g specific surface area by BET method, and 6.0-8.0pH in aqueous solution of 10g/100ml, H2O, amorphous and stable to heating in an oven at 200 deg.C for 3hr. A substance to diffuse into atmosphere is adsorbed on the amorphous calcium carbonate as a base material to give a material to release it.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to amorphous calcium carbonate, a method for producing it, and a sustained release product containing the same.

P, 74 acid calcium is crystallized 17'i 7j J:'
Three types of allomorphism are well known: , hexagonal calcite, orthorhombic arabite, and pseudohexagonal vaterite. Among these, calcite crystals are the most stable, and vaterite and aragonite crystals are generally said to be transformed into calcite crystals by physical treatments such as heating and grinding. In addition to the above three types of crystalline forms, calcium carbonate has also been extremely rarely reported to form an amorphous form [Gypsum to Lime No. 94, p. 39 (19
J. App. Chem, Vol. 17, p. 185 (1967)]. In other words, these documents state that when calcite crystal calcium carbonate is ground, the crystal structure collapses and it becomes amorphous, and that when calcium hydroxide powder is carbonated in the gas phase with carbon dioxide gas in a low humidity environment, it becomes amorphous. It has been reported that amorphous calcium carbonate can be obtained.However, the amorphous calcium carbonate shown in these literatures is usually only produced temporarily and is unstable, quickly changing to calcite crystals and its It is difficult to confirm the generation, or it cannot be taken out stably. After the straining, calcium hydroxide is carbonated in an aqueous solution such as sucrose using carbon dioxide gas at a low temperature of 15°C or less, and the product is dehydrated by spray drying or centrifugation, and then dried under vacuum. A method was proposed for stably replenishing amorphous calcium carbonate by keeping the amount of chemically bound water constant and not removing it [JP-A-56-124].
Publication No. 868]. However, the calcium carbonate produced by this method is used as an agent for introducing carbonic acid components into carbonated drinks, and it itself contains sucrose and other substances and remains amorphous, and it also contains chemically bound water. 2-5%
However, it is not included in the scope of calcium carbonate specified in the Japanese Pharmacopoeia, the Japanese Food Additives Standard, etc.

On the other hand, calcium carbonate has a high degree of whiteness, is non-toxic, is relatively inexpensive, and can be easily produced in various particle sizes [1].
Rubber, fillers for plastics, paints, extender pigments for ink, fillers for paper printing, etc.
Pigments for paper coating, medicine)! Ah, they are widely used as additives for cosmetics, food, agriculture, etc., and are manufactured and marketed with particle sizes, shapes, surface properties, etc. according to each use. It is made of luzite crystal. Amorphous calcium carbonate is considered to be a precursor of nuclear calcite type and other crystalline calcium carbonates, but if it can be stably produced and collected,
In addition to the wide range of uses of calcium carbonate known to date, the uniqueness of amorphous calcium carbonate can be used effectively for new uses such as active adsorbents, fillers with low specific gravity, and transparent pigments. Development of J9J is awaited and requested.

In view of the current situation, the present inventors have conducted extensive research into the production and application technology of amorphous calcium carbonate, which is desired in various fields. Calcium carbonate can be easily and stably produced, and amorphous calcium, which can be produced by 1Iji < 1, has a unique 18' quality and 1 raw form, and by utilizing these properties, We have found that it is useful as a sustained-release base to control the rate of volatilization of various volatile substances.

The present invention was completed based on these new findings.

That is, the present invention has a true specific gravity of 1.6 to 25 and a refractive index of 145 to 1.
．． 57, Specific surface area 20-600 ηg and l Of / l 00 ml H20 aqueous solution M) pH 6 by BET method
,0~8.0'f: has, is amorphous, and has a temperature of 200°C1
The present invention relates to an amorphous calcium carbonate characterized by being stable when heated in an oven for 8 hours, a method for manufacturing the same, and a sustained release product containing the same.

The amorphous calcium carbonate of the present invention did not show any peaks as a result of X-ray diffraction analysis, and showed a medium refractive index in the range of 1.45 to 1.57, indicating that it is amorphous. If we compare the physical properties of trinuclear amorphous calcium carbonate, which is its biggest feature, with the known crystalline calcium carbonate, we can see that it has the curvature shown in Table 1 below, and clearly (
It turns out that there are 11 differences.

However, each of the items in Table 1 was measured using the following method.
It's the same as Rainbow II.

True specific gravity: Liquid t? using a bignometer (ratio 0 bottle).
It was determined by the t-set method.

Refractive index: m, ll 5; · was determined by immersing a body with a known refractive index in r+l;

pH: fl, 1 (lfi'): 100
ml of hard + (47 Erlenmeyer flask, Ih L <
%,'! 1 made 1. ．． Replace pure water 1 fl Or
Add J, shake vigorously for 10 seconds, leave for 1 hour, and mix (Ijl, 5 Light < Jr, Stir).
Volume: 1'iil (Transferred to a 10 ml beaker and added using a glass polarized pH meter. B ET specific surface area: Micromeritics q+!
! JB ET ratio table 1rriid by N2 gas adsorption method! iia fllllllllll main device IllI was established.

Shape: Observed using a microscope (magnification: 2,000 to 20,000 times).

t 7'c Amorphous carbonate calcilla of the present invention" td
, amorphous μm and 1%+ fl for a long period of time (at least 1 month) when stored under sealed subcutaneous conditions at room temperature and low humidity.
l] Properties Overall properties [7] This stability is qualitatively 4 negative even after heating at 200°C for 13 hours in an air oven.
1% or less) or the presence of water causes crystalline calcium carbonate to dissolve.

In the history of the present invention), calcium oxide is a volatile substance that sublimates into the atmosphere under the conditions of ``6□'', for example, as a substance commonly used in fragrance powder 1. : A trade in which the substance that has been absorbed is released at an appropriate release rate according to the conditions other than those mentioned above. KER1iii.

Therefore, it is useful as a sustained release agent for the trade of volatile materials, and the present invention also provides such a sustained release agent. The manufacturing method is described below.

The present invention produces H4 by carbonating the raw calcium compound in an organic medium system.

Calcium compounds used as Ii'l) include calcium oxide, calcium hydroxide, calcium metal, calcium hydride, calcium chloride, calcium bromide, calcium iodide and calcium arsenate. The 1% sintered medium is used for monovalent, divalent, and trivalent alcohols having carbon atoms of 4 or more F. Especially good among these〕［
Examples include methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, ethylene glycol, and glycerin. These can be used alone or in combination of two or more. The above-mentioned medium may also contain 5% by volume of water, and when such a water-containing alcohol is used, the amorphous calcium carbonate desired in the present invention can be similarly obtained.

In 1. of the present invention, the oxidation reaction is carried out using carbon dioxide or a carbonate compound. The carbon dioxide used does not need to be a gas, and may be solid (dry ice). In general, for example, carbon dioxide gas with a concentration of about 30% can be conveniently obtained from the waste gas generated during greystone firing. Carbonate compounds %4+ include, for example, sl/lium carbonate, sodium bicarbonate, potassium carbonate, anthonium carbonate, etc. - Ammonium t'1 ammonium hydrate can be shown. The carbonation reaction is carried out by adding 1 liter of calcium, 1 liter of calcium, and 1 liter of the compound in an organic medium.Bubbling carbon dioxide into the solution or adding the carbonate compound with stirring or stirring after addition. This is done by mixing. In the case of blowing carbon dioxide, the inside of the reaction system may be made sufficiently uniform by stirring the gas alone, but it is usually preferable to employ a mechanical stirring operation. The temperature of the carbonation reaction is not particularly limited as long as it is below the boiling point of the organic medium in which J++ is present, but is usually about 45°C or below, preferably 0 to 45°C.
The raw calcium compound, which is considered to be pronated, is present ((Use of camellia medium and carbonating agent ν (11) can be determined as appropriate. Usually 4 medium 1. / raw calcium compound It is desirable to use less than about 4 moles of carbonate, generally from about 0.05 to 4 moles, and to use at least a reasonable amount of the carbonated shavings feedstock.

・Also, the carbonation reaction according to the present invention:,7;,',l':F
,,ammonium nitrate, ammonium acetate in the reaction system,
The presence of ammonium chloride or the like may sometimes promote the reaction. The reagents used as secondary reaction accelerators can be present in the reaction system in an amount of about 0.05 to 2 (l j 11%) of the compound (11).

When carbon dioxide is used as the carbonating agent, the end point of the oxidation reaction is determined by suspending a sample of the carbonation reaction system in water and determining its J and IH. Usually the p of the above suspension (as lnF/100ml water)
The point where H is approximately 6 to 7 is the end point. In addition, when a carbonate compound is used as a carbonating agent, the end point of the reaction is
It is preferable to set the time at which the reaction product no longer precipitates in the system. In this way, the organic medium containing the amorphous calcium hydroxide of the present invention can be dissolved.

The amorphous calcium carbonate of the present invention can be used for desired purposes in the form of a suspension in 1. or in the form of a base by appropriately converting it into a paste. The organic medium is removed, and the suspension is heated and pulverized according to a conventional method, or the suspension is dried with oil, whereby a powder product is isolated and collected.

Depending on the carbonation conditions, by-products may be produced in addition to the desired amorphous calcium carbonate, but these by-products can be removed by performing normal cleaning operations as necessary. The present invention provides a sustained release material containing amorphous calcium carbonate in the form of a suspension, paste, or powder that can be applied as described above, and the like as a base. Substances adsorbed and retained on the amorphous calcium carbonate base constituting the sustained-release body of the present invention are substances that volatilize or sublimate in the atmosphere under normal conditions, or substances that diffuse to the outside of the sustained-release body through moisture or heat. These substances include common fragrances, dyes, agricultural chemicals, medicines, taste substances, antifungal agents, and the like. Specific examples of secondary substances (hereinafter referred to as "active substances") include the following compounds.

(1) Fragrance 7-tc) Ethyl M'fiate, 7-netol, amyl cinnamic aldehyde, ethyl isovalerate, undecalactone, phosphorus, ethylene fluoride. Sylate, eugenol, ethyl caprylate, allyl caproate, ethyl caproate, l-carvone, cumin aldehyde, cinnamic alcohol, geraniol, dimethylbenzylcarbinyl acetate, silal, citronellol, dihydrojasmone, dimethylbenzylcarbinol, Tetrahydrolinalool, te/l/hineol, β-naphthyl ethyl ether, nonalactone, hydroxycitronellal, β-
Phenyl ethyl alcohol, ethyl phenylacetate, benzyl alcohol, maltol, musk, methyl n-methylenthionylate, menthol, ionone, linalool, limonene, etc. (2) Dyes methylene blue, methyl violet, sulfur black, indigo, Congo red, Kotsu ton brown,
Loxerin, orange l.

Nigrosine, rhodamine, etc. (3) Pesticides dimethyl fugate, 2-ethyl-t, a-hexanediol, indalone, dimethyl carbamate, irgavirin, PO2 agent (pentachlorpheno-)v), MEP
agent (dimethylthiophosphate), ECP agent (diethyldichlorophenylthiophosphate), chloropicrin, schizophrenia, naphthalene, paradichlorobenzene, metaldehyde (4) Pharmaceutical vitamin A, vitamin D, vitamin E1 vitamin and 1 phenolsulfone acid, phenylbentol, diflucortolon valerate, flumethacin bivalate, exalamide,
Cyclovirox olamine, cytucanin (5) Taste substances citric acid, lactic acid, malic acid, saccharin, stevioside, sorbitol, brucine, quinine, caffeine (6) Anti-mold agents - dichlorodiphenylmethane, ortho-phenylphenol, diphenyl, thiabendazole ( 7) Other volatile rust preventives: trimethylsulfonium nitrite, diisopropylammonium nitrite, 1,2.8 benzotriazole pesticides: isobrothiolane agents, carpendazole agents Plant growth regulators: Bee agent (6- (N-benzyl)aminopurine], gibberellin, lilabone agent, N,N,NL)dimethyl-1-methyl-8-(2,6,6-drimethyl)L/-2-cyclohexen-1-yl) -2-propenylammonium food preservative: sodium dehydroacetate, sodium propionate, lauryltrimethylammonium-2,4°5-trichlorophenoxide antioxidant: 4A-thiobis-(3-methyl-6-butylphenol), Dilauryl thiodipropionate, pentaerythrityl tetrokis(8-(8,5-di-kushabutyl-4-hydroxyphenol)propionate) UV absorber: 2,4-dihydroxybenzophenone,
Phenylsalicylate, 2-(2-hydroxy-57-melpheny7+/)-bensotriazole rat repellent: β-(2-(8,5-dimethyl-2-O
XO・cyclohexyl)-2-hydroxyethyl]glutarimide Liquid blowing agent: hala・toluene・sulfonyl azide The sustained release material of the present invention which adsorbs and retains the above-mentioned various agents η can be used simultaneously with the production of the amorphous calcium carbonate of the present invention. Alternatively, it can be produced by previously producing the calcium carbonate and then adsorbing the active substance thereto. Representative examples of the method include the following.

(]) When producing the amorphous lucium acetate of the present invention, a desired active substance is added and present in the organic medium used,
The carbonation reaction described above is carried out.

(2) Adding the desired active substance to the organic medium suspension containing the amorphous calcium carbonate obtained by the carbonation reaction described above.

(3) The amorphous calcium carbonate powder product of the present invention is sprayed with a liquid of the active substance previously dissolved in a suitable solvent, or the powder product and the active substance are immersed in a suitable solvent, and then the solvent Remove (dry).

When using any of the above methods, the amount of the active substance to be used depends on the type of the active substance, the desired use of the sustained-release material to be rubbed, and the volatilization rate (duration time) of the active substance from the sustained-release material.
The saturation absorption fi of the amorphous calcium carbonate of the present invention is appropriately determined according to the following. With M as the upper limit, the active substance commonly used in j18 is almost completely adsorbed and retained. Generally, the adsorption/retention strength is preferably 0.001 to 20 times as heavy (tW) using amorphous calcium carbonate as the base material. In addition, examples of the solvent used in the method shown in (3) above include methanol, ethanol, acetone, ff
+ethyl acid, butyl cellosolve, toluene, hecan,
Examples include tetrachloride disease and chloroform. As a drying means, heating to the boiling point of each solvent or a temperature higher than that,
It is possible to employ methods such as hot air drying under reduced pressure or ventilation drying with dry air.

Thus, the sustained release product of the present invention can prevent alteration, deterioration, etc. of the active substance over a long period of time, and one can easily release and supply the active substance at an appropriate release rate. The original action of the active substance 'H can be maintained for a long period of time.

The present invention will be explained in detail below by giving Examples and Comparative Examples.

Example 1 Glass container equipped with a stirrer and gas introduction tube (container 44)
800 f of calcium hydroxide powder and 2 l of 1/2 liter of calcium hydroxide powder were added to the mixture, and at 18°C (i.e. temperature), 3°% by volume of carbon dioxide gas was injected under pressure to carry out the carbonation reaction. The collected sample was suspended in water by rambling as needed, and the reaction (maximum intensity (27"C) was completed when the pH of the 10% suspension reached 7).

The entire product obtained was filtered with suction to remove methanol, then dried in an air circulation heated dryer at 110°C for 5 hours, and the dried product was pulverized to produce the amorphous calcium carbonate powder of the present invention 880! /wo・i1(ta.

The X-ray diffraction analysis diagram (Oukα, N1 filter) of this powder is as shown in FIG. 1, and no peaks are observed, indicating that it is amorphous. Furthermore, this powder was tested in accordance with the Japanese Pharmacopoeia's calcium carbonate confirmation test method and was confirmed to be calcium carbonate. its physical nature
7 is shown in Table 2.

Furthermore, this powder was kept in an oven at 200° C. for 3 hours and then similarly subjected to X-ray diffraction analysis. The results are as shown in FIG. 2, and the powder was stable with no peaks observed. The X-ray diffraction pattern after baking at 400°C for 3 hours in an oven is as shown in Figure 8, confirming that it has changed to calcite.

Further, FIG. 4 shows a differential heat/thermobalance measurement diagram of the amorphous carbonate calcyano powder obtained above. 400° from the original drawing
It can be seen that the loss on heating in C'l: is 1.0% or less. The measurement conditions in the figure are as follows, and in the figure (
1) is the differential thermal curve (DTA), and (2) is the heating loss interval f.
a (T O), and (3) shows the temperature curve (°C).

Sample collector: l1mF! Heating rate: 10'c/min Differential thermal sensitivity: ±100μ■ Standard sample: α-AN20s Example 2 Glass container equipped with a stirrer and gas inlet tube (capacity:
Calcium oxide powder (200 mesh pass product) 28
Add y and 500 ml of methanol, and stir for 25 minutes.
Carbonation reaction (maximum temperature 82°C) was carried out at 'C (room temperature) by passing carbon dioxide gas whose concentration had been adjusted to 80% by volume with air in advance, and the end point of the reaction was determined by the same method as in Example 1. .

Methanol was removed from the thus crushed product by suction filtration, and the residue was dried in a dryer at 110°C for 8 hours and ground to obtain the amorphous calcium carbonate powder 45 of the present invention.
Got FI.

As a result of X-ray diffraction analysis, no peaks were observed in the powdered powder as shown in Figure 1, and it was confirmed to be calcium carbonate by the Japanese Pharmacopoeia's calcium carbonate confirmation test method.

Even after being kept in an oven at 200°C for 8 hours, no peaks were observed in X-ray diffraction analysis, and the product was stable. The physical sex tag for this item is as shown in Table 2.

Comparative Example 1 Into the same reaction vessel as in Example, 250 ml of calcium hydroxide aqueous suspension (milk of lime slurry) with a concentration of 4 (ljijid%) was added.
Add g and methanol LN (the relative humidity of calcium hydroxide to methanol in this system is 27 l/l methanol, and the water content in methanol is 10% by volume), and add 30 vol. Carbonation reaction was carried out using carbon dioxide gas of 5%, and the completion of the carbonation reaction was determined by the same method as in Example 1. When the obtained product was suction-filtered, almost all of it was I passed through the door paper. 6) Regarding the shattered product (methanol suspension), the powder obtained by volatilizing methanol was found to be crystalline tt (Patellai L-type) calcium carbonate as a result of X-ray diffraction analysis. The physical properties lPd of the fish are shown in Table 2.

Example 3 Glass container equipped with a stirrer and gas introduction tube (capacity 1 g)
To, calcium hydroxide powder 747 and O methanol 500
, mβ was added, and the carbonation reaction was carried out by stirring (30% by volume of carbon dioxide gas at a rate of 51/min) and the selective oxidation reaction was completed as determined by the same method as in Example 1. At this point (about 15 hours later), the methanol suspension of the product was removed by suction filtration to separate the methanol, and the residue was dried in a dryer at 110°C for 2 hours to obtain a powder of 91f.
4 Nosha 2 The result of the analysis was that it was amorphous, showing no peaks at all, as shown in Figure 1, and as a result of the test according to the Japanese Pharmacopoeia, it was confirmed that it was calcium carbonate. Even after being held at 200°C for 13 hours in an open state, it was stable and showed no peaks in X-ray diffraction analysis.

The physical properties of this product are shown in Table 2.

Example 4 In Example 8, 500 ml of methanol was
-1490m1 and LOml of water! (Mep)-rv), carbonation reaction was carried out in the same manner to obtain amorphous calcium carbonate powder 849 of the present invention. This product is stable (heated in an oven at 200°C for 3 hours) and its physical properties are shown in Table 2.

Comparative Example 2 In Example 8, methanol/L/500 ml was mixed with methanol 1v450m4 and water 50ml1lC mepnow
The carbonation reaction was carried out in the same manner, except that the carbonation reaction was carried out in the same manner, and the time point at which the reaction ended was determined in the same manner. Since the product at the end of the reaction passed through P paper during suction filtration and it was impossible to separate the P solution, the P liquid was heated and dried to volatilize the methanol, but during the drying process it was already crystalline () (tellite type). ) It was confirmed by X-ray diffraction analysis that it was calcium carbonate. The physical properties of this are shown in Table 2. Example 5 A glass container (capacity 150
0 m4) of metallic calcium lOf and methanol 25
0m/, and without stirring, at 25'C (room temperature), carry out the carbonation reaction by passing carbon dioxide gas whose concentration was adjusted to 80% by volume in advance in the same manner as in Example 1. The time point at which the reaction ended was determined.

Methanol was removed from the resulting product by suction filtration, and the residue was dried in a drier at 110°C for 8 hours to obtain amorphous calcium carbonate powder 20FI of the present invention.

As a result of X-ray diffraction analysis, no peak was observed in the obtained powder as shown in FIG. 1, and it was confirmed to be calcium carbonate according to the Japanese Pharmacopoeia's calcium carbonate confirmation test method.

Further, even after being kept in an oven at 200°C for 8 hours, no peaks were observed in X-ray diffraction analysis, and the product was stable. The physical properties of this product are shown in Table 2.

Example 6 In Example 3, methanol 500m/? The carbonation reaction was carried out in the same manner as in Example 1, except that 1,500 ml of n-propyl alcohol/I was used, and the time to complete the reaction was determined. It took about 6 hours. The amorphous calcium carbonate powder 9Of of the present invention was obtained by processing in the same manner as in Example 8. The physical properties of this powder are shown in Table 2.

Example 7 In Example 3, methanol 6110 mJl? t-n
-propyl alcohol-/I 1500 mN, and ammonium chloride 0.4f as a reaction accelerator in the medical oxidation reaction system.
was added, a carbonation reaction was carried out in the same manner, and the time when the reaction was completed was determined to be approximately 1.5 hours. Table 2 shows the physical properties of amorphous calcium carbonate powder (yield: 91 g) obtained by treating the obtained product in the same manner.

Example 8 In Example 3, carbonation reaction was carried out in the same manner as in Example 3 using 500 mβ of n-butyl alcohol instead of 50 ml of methanol, the end point of the reaction was determined, and the product at this point (n-butyl alcohol suspension ) was dried by heating to obtain amorphous calcium carbonate powder 829 of the present invention.

This product is stable (open heating at 200°C for 18 hours) and its physical properties are as shown in Table 2.

Example 9 In Example 8, 500 mg of ethylene glycol was used in place of 5 oomJf' of methanol, and the ethylene glycol suspension was then heated and dried in the same manner as in Example 8 to obtain amorphous calcium carbonate powder 909 of the present invention. This product is stable (open heating at 20°C for 8 hours), and its off-shore fishing properties are as shown in Table 2.

Example 10 In Example 3, 111 g of calcium hydroxide powder was used, and 500 m of glycerin was used instead of 500 m of methanol.
Using 1j, carbonation reaction was carried out in the same manner to obtain a product as a glycerin suspension, which was directly analyzed by X-ray diffraction.It was found to be amorphous with no peaks observed, and the results of the test according to the Japanese Pharmacopoeia were It was recognized as calcium carbonate.

This product can be used as a base for the sustained release product of the present invention in the form of a paste or by concentrating it into a paste form.

Example 11 Put 500 ml of ethyl alcohol into a glass container (volume 111) equipped with a stirrer, and add calcium chloride (Ca04).
56 Add Fl, stir to dissolve, and continue stirring to add sodium carbonate (Na2Co3・H2O)61
F/ was added to precipitate the reaction product.

The IJium chloride produced as a by-product during this reaction was washed away, followed by suction filtration and heat drying to obtain a powder of 42f.

The obtained powder showed no peaks in X-ray diffraction analysis and was amorphous, and was found to be calcium carbonate by 4irr when tested according to the confirmation test method of the Japanese Pharmacopoeia. This product showed no peaks in X-ray analysis and was stable even after being kept at 2flO'C for 3 hours in the open. Its physical properties are shown in Table 2.

Example L2 Put 500 ml of ethyl alcohol into a glass container equipped with a stirrer (capacity IJI?), add 89 nitric acid (Ca(No3), 4H20), and stir to dissolve. While continuing to stir, add hydrogen carbonate to
Ammonium nitrate (NH4HCOs) 4 (l f) was added to precipitate the reaction product. Ammonium nitrate produced as a by-product during this reaction was washed away, and then filtered with suction and dried by heating to form a powder of υ39y. I got it.

This powder showed no peaks in X-ray diffraction analysis and was amorphous, and was confirmed to be calcium carbonate in a test using the confirmation test method of the Japanese Pharmacopoeia. This material showed no peaks in X-ray analysis and was stable even after being kept in an oven for 20 (18 hours). Its physical properties are shown in Table 2.

Example 13 In a glass container (volume: lg) equipped with a stirrer,
Add 500 md of ethyl alcohol, add 74 f of calcium hydroxide (Ca(OH)), and add 4 s of sodium hydrogen carbonate (Nanco, ) while stirring.
y was added to precipitate the reaction product. After washing away the hydroxide (hydroxide) produced as a by-product during this reaction,
A powder of #)88f was obtained by suction f1 filtration and heat drying.

This powder showed no peaks in X-ray diffraction analysis and was amorphous, and was determined to be calcium carbonate by a small sample according to the confirmation test method of the Japanese Pharmacopoeia. This product showed no peaks at all in X-ray analysis and was stable even after being kept at 200°C for 13 hours in the open. Its physical properties are shown in Table 2.

The physical properties of the amorphous calcium carbonate of the present invention are shown in Table 2 below, along with the raw material calcium compound, the type and amount of organic medium used, and the carbonation reaction method for each of the above-mentioned sides.

[*1] in Table 2 indicates the reaction accelerator (3
The ratio of ammonium nitride to the raw material calcium compound is approximately 0.
．． Indicates that 5 times and 80% were added.

Example 14 In Example I, a carbonation reaction was carried out using 800 g of calcium hydroxide powder, 3 g of menthol, and 2 e of methanol to obtain a powder product (sustained release) of about 3807 g. Regarding this sustained release material, the fragrance release paper test results were as shown in Table 3.

Example 15 After completing the carbonation reaction in Example 1, 3 g of menthol was added and the reaction was continued for about 15 minutes. Stirring was continued for 30 minutes, followed by suction filtration and drying to obtain a powder product (sustained release) of about 3801. Regarding this sustained release product, the fragrance release test results were as shown in Table 3 and were disappointing.

Example 16 The powdered product 380% obtained according to Example 1 was placed in a solution of 37% Men I-1 in 16% methanol, left to stand for 30 minutes, and then dried under suction to about 380%
G's celiac product (sustained release) is given. The release test results of this sustained-release product: N'i rice 1 were as shown in Table 8.

Comparative Example 3 Dissolved 3g of menthol in methanol 1β
'1i1' contains crystalline calcium carbonate (made by Shiraishi 1 Hata [
Whiten P-10J, Calcite iLL&) 380g
After stirring for about 30 minutes, about 380g of powder was removed by suction and over-drying. )Ta. The fragrance release test results for this powder were as shown in Table 3.

Fragrance release test> 10 liters of sample powder was placed in a glass Petri dish at a constant temperature of 65% humidity and a temperature of 2 fl °C.
A humid room was maintained at 11C and the change in scent over time was investigated. The results are shown in Table 8.

Example 1 '1 In Example 1, after the carbonation reaction was completed, Geranimer (
38 gf: Add frosting and continue stirring for about 15 minutes.
1 of the powdered product (slow release) was added. The obtained a-(material) was mixed with Getalc and stearic acid magnesium to prepare fragrance power ? It was shown to.

Ratio Medium '2r 114 Talc, guosium stearate, crystalline calcium IV acid (Shiraishi Kogyo Co., Ltd. 3J "P (:J calcite crystal)" and geraniol, respectively, 65:5:27:3 (mJt ratio)
A fragrance powder was prepared by mixing the ingredients in the following proportions, and a test 17 was conducted to determine the IM property of the fragrance. The results are shown in Table 4.

The persistence of fragrance in Table 4 was determined by spraying fragrance powder of each tone on the bodies of two people after taking a bath, and checking the presence or absence of the fragrance after a certain period of time. .

Example 18 After completing the carbonation reaction in Example 1, methylene blue (
8 g of dye) was added, the mixture was kneaded and stirred for about 15 minutes, and about 380 g of powder product (sustained release material) was obtained by suction filtration and drying. 100g of the browned sample
Suspend the sample in water and take out the sample at regular intervals.
After drying, the whiteness of the powder was measured, and the rate of change with respect to the whiteness of the initially obtained product was determined. The results are shown in Table 5. The whiteness of the amorphous calcium carbonate powder (before dyeing) obtained in Example 1 was 95.

Comparative Example 5 380f of crystalline calcium carbonate (manufactured by Shiraishi Kogyo [Whiten P-10J calcite crystal, its whiteness is rated at 95) was added to a solution of methylene blue 8FI dissolved in 1 liter of methanol, and stirred for about 30 minutes. After drying, suction yielded about 380 g of powder by overdrying.

This powder is the same as Example 18! The results of the test are shown in Table 5.The whiteness in the above test was measured using a Kerato photoelectric whiteness meter using a blue filter.

Example 19 After the carbonation reaction in Example 1, 38v of dimethyl phthalate (a mosquito repellent) was added and the mixture was heated for about 15 minutes.
Continue stirring and dry by suction until approximately 4.
00g of powder product (sustained release) was obtained. A repellent was prepared by mixing 30% (by weight) of this sample in vaseline, and its repellent power was tested. The results are shown in Table 6. Comparative Example 6 Vaseline, crystalline calcium carbonate (Shiraishi Kogyo [Whiten P-10J Calzite Crystal)] and dimethyl phthalate were mixed in a ratio of 70:27:8 (weight ratio), respectively. A repellent was prepared and tested for its repellent power. 6th result
Shown in the table.

In this test, the mosquito repellency was measured as follows. That is, each of the prepared drugs was rubbed thinly onto the hands and legs of two people, who stood in a place where many mosquitoes were infested, and observed how mosquitoes approached each other over a certain period of time.

Example 20 After the carbonation reaction in Example 1 was completed, 88f of benzotriazole (rust preventive agent) was added, stirring was continued for about 15 minutes, and suction p was over-dried to produce a powder product of about 400f/( A sustained-release drug was obtained.

Table 7 shows the results of the rust prevention test on the obtained sustained release material.

Comparative Example 7 Crystalline calcium carbonate (Shiraishi Kogyo 1-P CJ calzite crystal) and benzotriazole were each mixed at 90:
A rust preventive agent was prepared in a ratio of 10 (weight ratio), and the results of the rust prevention test are shown in Table 7.

Reference Example Table 7 shows the results of the rust prevention test with no rust inhibitor.

Rust prevention test〉 200g of sustained release sample was placed at the bottom of a 300 mm diameter desiccator (without lid), a rolled steel plate was placed on a shelf, and the temperature was kept constant at 65% humidity and 30°C. They were kept in a constant humidity room and observed to see if rust appeared.

*A steel plate specified by J Engineering 5G8141 was immersed in 5% by weight saline solution for 5 seconds, then pulled out and dried.

[Brief explanation of the drawing]

Figure 1 is an X-ray diffraction diagram of the amorphous calcium carbonate powder of the present invention obtained in Example 1, and Figure 2 is an X-ray diffraction diagram of the amorphous calcium carbonate powder obtained in Example 1.
The X-ray diffraction pattern after time-holding, Figure 3 shows the 400'
FIG. 4 shows the X-ray diffraction pattern after firing at C for 8 hours and the differential heat/thermobalance measurement chart of the same powder, respectively. (that's all)

Claims (1)

[Claims] O) true specific gravity 1.6 to 25, refractive index 1.45 to 1.57,
Specific surface area 20-600 m2//g and 1 by BET method
0 g/l 00ml I (20 aqueous solution (D pH 6,
0-8. (1, amorphous, 200°C13
Amorphous calcium carbonate characterized by being stable when heated in an oven for hours. ■ Calcium compounds are carbonated in an organic medium system to produce true specific gravity of 1.6-2.5, refractive index of 1.45-1-57,
Specific surface area 20-600Tr by BET method? / 9 and 010g/l 00ml H20 aqueous solution (DpH6
, 0 to 8.0, is amorphous, and is stable when heated in an oven at 200° C. for 13 hours. 2. A method according to claim 2, wherein the calcium compound is selected from calcium oxide, calcium hydroxide, calcium metal, calcium hydride, calcium halide and calcium nitrate. (2) Organic IIV: The method according to claim 2, wherein the system is selected from monohydric, dihydric and trihydric alcohols having carbon v14 or less. (2) The method according to claim 21:i'iK, wherein the carbonation reaction is carried out using carbon dioxide or a carbonate compound. 2. The method according to claim 2, wherein the carbonation reaction is carried out in the presence of a reaction promoter selected from ammonium nitrate, ammonium acetate and ammonium chloride. ■ True specific gravity 16-2゜5, refractive index 1.45-157, B
Specific surface area 20-600m2/g and 10 by ET method
f/ ], 00ml H,0 aqueous solution pH 6,0-8
．． 0, is amorphous, and is stable when heated in an oven at 200°C for 13 hours, which is characterized by containing calcium carbonate as a base.