CN-121986077-A - Calcium carbonate compound and aqueous composition

Abstract

The invention provides a calcium carbonate compound and an aqueous composition which can reduce shrinkage of a heating surface and increase of temperature of a back surface even more when used for an inorganic molded body as a building material. The present invention provides a calcium carbonate compound, wherein the viscosity of a dispersion liquid in a state of being dispersed in water at a concentration of 33 mass% is 1000 cP to 2000 cP inclusive at 30 rpm. The viscosity of the dispersion liquid of the calcium carbonate compound in a state of being dispersed in water at a concentration of 33 mass% is preferably 1000 cP to 2500 cP inclusive at 6 rpm. The ratio μ 6 /μ 30 of the viscosity μ 6 of 6 rpm to the viscosity μ 30 of 30 rpm of the dispersion in which the calcium carbonate compound is dispersed in water at a concentration of 33 mass% is preferably 1.0 to 2.5.

Inventors

• MATSUI KOJI
• TAKENAKA DAISUKE
• SATOMURA HIDEAKI

Assignees

• 神岛化学工业株式会社

Dates

Publication Date

20260505

Application Date

20240829

Priority Date

20231011

Claims (12)

1. 1. A calcium carbonate compound has a viscosity of 1000 to cP and 2000 to cP at 30 rpm in a state where the calcium carbonate compound is dispersed in water at a concentration of 33 mass%.
2. 2. The calcium carbonate compound according to claim 1, wherein the viscosity of the dispersion in a state of being dispersed in water at a concentration of 33 mass% is 1000 cP to 2500 cP inclusive at 6 rpm.
3. 3. The calcium carbonate compound according to claim 2, wherein the ratio μ 6 /μ 30 of the viscosity μ 6 of 6 rpm to the viscosity μ 30 of 30 rpm of the dispersion in a state of being dispersed in water at a concentration of 33 mass% is 1.0 to 2.5.
4. 4. The calcium carbonate compound according to claim 1, wherein an aspect ratio of an average major axis to an average minor axis is 2 to 19.
5. 5. The calcium carbonate compound according to claim 1, wherein the average particle diameter is 1.1 μm or more and 12.5 μm or less as measured by a laser diffraction method.
6. 6. The calcium carbonate compound according to claim 1, wherein the average long diameter obtained by observation with a scanning electron microscope is 0.5 μm or more and 25 μm or less.
7. 7. An aqueous composition comprising water and the calcium carbonate compound according to any one of claims 1 to 6.
8. 8. The aqueous composition according to claim 7, wherein the water content is 40% by mass or more and 99% by mass or less.
9. 9. The aqueous composition according to claim 7, wherein the water content is 5% by mass or more and 60% by mass or less.
10. 10. The aqueous composition according to claim 7, which is obtained without drying in the step of producing a synthetic calcium carbonate compound.
11. 11. An inorganic molded article comprising the calcium carbonate compound according to any one of claims 1 to 6.
12. 12. A method for producing an inorganic molded article, comprising the step of molding an inorganic composition comprising the aqueous composition according to any one of claims 7 to 10.

Description

Calcium carbonate compound and aqueous composition Technical Field The present invention relates to a calcium carbonate compound and an aqueous composition. Prior Art Inorganic molded articles are molded articles made of inorganic substances such as hydraulic materials and silicic acid materials, and are widely used as exterior wall materials, roof base materials, roof materials, etc. for houses, etc. because they have properties such as fire resistance, light weight, high strength, and workability. On the other hand, in recent years, there have been attempts to reuse waste, exhaust gas, by-products such as waste heat, and by-product energy generated secondarily in industrial processes, due to the increasing environmental awareness. As a technique for improving the fire resistance of one of important safety properties required for inorganic molded products and promoting reuse of waste, there has been proposed a technique in which "seawater residue mainly composed of calcium carbonate and magnesium hydroxide", which is by-produced in a step of removing carbonate from seawater, is applied to a calcareous material in a step of producing magnesium hydroxide from seawater (japanese patent application laid-open No. 2012-116685). [ Prior Art literature ] [ Patent literature ] [ Patent document 1] Japanese patent application laid-open No. 2012-116685. Disclosure of Invention [ Problem to be solved by the invention ] However, even with the above-mentioned technique, there is a possibility that shrinkage of the heating surface or an increase in the temperature of the back surface occurs during heating, and further improvement of the fire resistance of the building material as an inorganic molded body is demanded. Further, carbon dioxide is widely known as a greenhouse gas, and reuse or reduction of carbon dioxide, which is a secondary product produced in an industrial process, has become an urgent issue. The purpose of the present invention is to provide a calcium carbonate compound and an aqueous composition which can exhibit a higher level of fire resistance when used in an inorganic molded body as a building material. [ Means for solving the problems ] As a result of intensive studies, the present inventors have found that the above problems can be solved by the following constitution, and have completed the present invention. In one embodiment, the present invention relates to a calcium-based carbonic acid compound, The viscosity of the dispersion liquid in a state of being dispersed in water at a concentration of 33 mass% at 30 rpm is 1000 to cP and 2000 to cP. According to the calcium carbonate compound, the viscosity of the dispersion liquid in which the calcium carbonate compound is dispersed at a specific concentration is within a specific range of 30 rpm, and therefore, when the calcium carbonate compound is used in an inorganic molded article, the fire resistance can be exhibited at a higher level. The reason for this is not clear, but is presumed to be as follows. The present inventors have studied on the case where a dispersion of a calcium-based carbonic acid compound obtained in the step of producing a synthetic calcium-based carbonic acid compound is directly applied to the process of producing an inorganic molded body, and as a result, have found that, when the dispersion has the above-described specific viscosity, it is possible to suppress the shrinkage of the heating surface and the increase in the back surface temperature at the time of heating, respectively. The dispersion liquid in the state in which the calcium-based carbonic acid compound is dispersed has a relatively high viscosity in a specific range. The reason for this is presumably that the aggregation of the calcium carbonate compound is reduced and the degree of dispersion in the state of primary particles is high. When the dispersion liquid containing the calcium carbonate compound in the form of primary particles is directly introduced during the production of the inorganic molded article, the calcium carbonate compound is similarly dispersed in the inorganic molded article in the form of primary particles. As a result, the calcium carbonate compound functions as a so-called reinforcing material, whereby shrinkage of the heating surface can be suppressed. In addition, since the calcium-based carbonic acid compound having low thermal conductivity is dispersed in the same way, the thermal insulation property of the inorganic molded body in the thickness direction is improved, and the rise in the back surface temperature can be suppressed. It is presumed that by these composite actions, the shrinkage of the heating surface and the rise in the temperature of the back surface during heating can be suppressed at higher levels, respectively, and the high level of fire resistance can be exhibited in the entire inorganic molded body. In the present specification, the term "calcium carbonate-based compound" is a compound containing calcium car