JPS5957937A - Manufacture of calcium carbonate hardened body - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention The present invention uses pearl powder, coral powder, or crustacean shell powder as raw materials to produce hardened calcium carbonate that can be used as accessories, interior decorations, or interior materials such as tiles. Regarding how to.

As is well known, pearls and corals have been used since ancient times as jewelry or interior decorations, but some of the so-called scrap pearls and corals that can be used for jewelry or interior decorations are used as feed,
Although it is used as a raw material for whitewash and as a cement compounding material, most of it is usually thrown away without being used. The same applies to the shells of crustaceans,
Most of it is thrown away, except for some that is used as feed.

However, pearls, corals, crustacean shells, etc. are mainly composed of calcium carbonate, and since calcium carbonate is aragonite (orthorhombic system) and calcite (hexagonal system) with low crystallinity, chemically Compared to synthesized light calcium carbonate (precipitated calcium carbonate) and heavy calcium carbonate derived from limestone, it has the property of being easier to sinter. Moreover, pearls, corals, shells, etc., although in small amounts, contain organic substances (chitin or conchiolin) that are thought to function as binders during sintering. In addition to this, a true sphere,
Corals, shells, etc., and their crushed products take on anisotropic shapes such as flat and spindle shapes, which is an excellent feature for making sintered and hardened bodies.

The present invention focuses on the above-mentioned characteristics possessed by pearls, corals, shells, etc., and creates a method for producing hardened calcium carbonate that opens the door to the effective use of scrap pearls, corals, and shells of crustaceans, which have been little utilized in the past. Its characteristics include 20 to 100 wt% of powder selected from pearl powder, coral powder, and crustacean shell powder with a particle size in the range of 0.1 μ to 105 μ; is 500μ~201
The method involves blending an inorganic coloring agent corresponding to 0 to 50 wt% of the mixture into a mixture with 0 to 80 vrt% of aggregate in the range of 1011, and press-molding this at a temperature of 400 to 1500°C. Note that the particle size in this specification means an average particle size unless otherwise specified.

According to the present invention, pearl powder, coral powder, shell powder (hereinafter, these powders are collectively referred to as pearl powder, etc.) have a particle size of 0.
A particle size of 1μ to 105μ is used, but the particle size can be selected within the above range depending on the C ratio, density, and surface hardness of the final product, which is applied to the molded product. Preferably, and in this case, the ratio of the respective three particle sizes of coarse, medium and fine particles is approximately 5:3:1. By the way, coarse grains (particle size 5-10μ), medium grains (particle size 3-6μ)
μ) and fine particles (1 to 2 μ) are approximately 40:20:
If pearl powder or the like having a weight ratio of 40 is used, a dense molded body can generally be obtained.

As mentioned above, it is thought that the organic substances originally contained in pearl powder etc. act as a binder during sintering, so the pearl powder etc. used in the present invention must not have been subjected to firing or chemical treatment. preferable. However, with pearl powder and the like that contain a large amount of organic matter, segregation of organic matter occurs along the stress distribution line during pressure molding, and the molded product after being left to cool tends to have cracks along the stress distribution line. Therefore, if such a situation is a concern, it is possible to subject pearl powder or the like to a mild heat treatment in advance. The occurrence of oxidation due to the segregation of organic matter can be prevented by mixing aggregate with pearl powder, etc., as described below, or by increasing the mixing ratio.

The aggregate of the present invention performs the same function as coarse aggregate or fine aggregate in concrete moldings, and has a particle size of 5.
Any inorganic material with a diameter of 00 μm to 20 m can be used, and its type does not matter.

However, the coarse grains, medium grains, and fine grains mentioned above are about 40
:20:40 weight ratio is used, the particle size of the aggregate is in the range of about ioo to 200 times the particle size (3 to 6μ) of medium particles such as pearl powder. Although it is preferable to deviate from this range, the compactness of the concrete molded body will only be reduced to some extent. However, when an inorganic material that forms a glass phase at the molding temperature is used, cracks generally occur after molding. Therefore, common materials such as limestone and marble are used as aggregates in the present invention. Artificial gemstones can also be used as aggregates if necessary.

In the present invention, the mixing ratio of aggregate and pearl powder etc. is 0 to 8.
It is in the range of 100 to 20 parts by weight to 0 parts by weight.

Of course, the larger the particle size of the aggregate used, the smaller the amount of aggregate used must be.

Although the method of the present invention does not necessarily require the use of a colorant, any inorganic colorant (inorganic pigment) may be used as necessary.
can be used.

The amount of inorganic coloring agent used is 20 to 100 wt% such as pearl powder.
It is appropriate that the amount is 50 wt % or less of the mixture of and aggregate θ ~ 80 wt %.

A mixture of 20 to 100 wt% of pearl powder and 0 to 80 wt% of printing material, and an inorganic coloring agent added as necessary, is
By press-molding this at a temperature of 400 to 1500°C, the desired hardened calcium carbonate body can be obtained. The pressure during molding is preferably 100 kg/d or more,
The longer the molding time, the better, but approximately 5 to 90 minutes is suitable. Although such pressure molding can be carried out by hot pressing, HIP (hot isostatic pressing) is most preferable.

As is clear from the above explanation, according to the method of the present invention, interior decoration items such as wall hangings and ornaments can be made from scrap pearls, coral scraps, or crustacean shells, which have not been effectively utilized in the past. It can manufacture accessories such as pendants, brooches, and zekun, as well as interior materials such as tiles.

Example 1゜Coarse particles (
40g of medium particles (particle size 8μ), 20g of medium particles (particle size 5μ), and 40g of fine particles (particle size 1.5μ) were collected and mixed in a V-type blender for 30 minutes, and this mixture 159 was heated at a temperature of 600°C and a pressure of 10%.
Hot pressing was carried out for 30 minutes under a pressure of 00 kg/i to obtain a disc-shaped molded product with a diameter of about 40 cm and a thickness of 5 cm. The surface of this molded body was polished with 1500 grit sandpaper to prepare a sample (
A).

Example 2 Deep sea coral powder (12 g of particle size 8 μ, 6 g of 5 μ
, 12g of 1.5μ) and 2 limestone (750μ) (
The sample (
B) was obtained.

Example 3 The blending amounts of coarse particles, medium particles, and fine particles were 89.4 g and 8I, respectively, and limestone 80 with a particle size of 750 μ was added to reef-building coral powder.
Sample (C) was obtained in exactly the same manner as in Example 1, except that a mixture of g was used.

Example 4 Sample (D) was obtained in exactly the same manner as in Example 1, except that pearl powder was used instead of reef-building coral powder.

Example 5 A powder obtained by thoroughly washing and pulverizing the carapace of a king crab was prepared, and a sample (l was prepared.

Reference Example The same operation as in Example 1 was repeated except that the temperature conditions for pressure molding were changed from 600°C to 350°C to obtain a sample (F).

Next, each sample obtained in the above Examples and Reference Examples was
After drying at ℃ for 4 hours, cooling in a desiccator, water absorption rate,
Density, compressive strength and Mohs hardness were measured. Water absorption was measured according to JIS Z-0701, and density IIJ was determined according to JIS Z-8807-76K. Compressive strength was expressed as the value obtained by dividing the fracture load in the axial direction by the cross-sectional area. Moreover, Mohs hardness was measured using a Mohs hardness meter.

The measurement results are shown in the table below.

Margin below Table 1

Claims (1)

[Claims] 1. Pearl powder having a particle size in the range of 0.1μ to 105μ;
Powder selected from coral powder and crustacean shell powder 20-1
00 wt% and 0 to 80 wt% of aggregate having a particle size in the range of 500μ to 20wn.
An inorganic coloring agent corresponding to wt% is blended, and this is heated at a temperature of 40%.
A method for producing a hardened calcium carbonate body, which comprises pressure molding at 0 to 1500°C. 2. The method according to claim 1, wherein limestone or marble is used as the aggregate.