JPH0515274A - Method for forming pearl - Google Patents

Abstract

PURPOSE:To obtain pearls, excellent in appearance and capable of readily controlling their grain diameter by forming pearl mother nuclei having high biocompatibility with the pearl oysters. CONSTITUTION:Pearl mother nuclei formed by including a calcium phosphate- based compound in a resin are inserted into pearl oysters to form pearls in the pearl oysters. Thereby, the objective pearls having high appearance properties, grain diameter and specific gravity controllabilities are obtained by mixing 50wt.% fine particles of hydroxyapatite with 50wt.% polymethyl methacryalte, forming pearl mother nuclei having 6.5-30mm grain diameter and inserting the resultant pearl mother nuclei into the pearl oysters.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming pearls, and more particularly to a method for forming pearls using a pearl nucleus containing a calcium phosphate compound such as hydroxyapatite.

[0002]

2. Description of the Related Art Conventionally, as a method for forming pearls of this kind, for example, spherically ground shells of Victory shellfish, red shellfish, etc. have been used as a pearl nucleus, and this pearl nucleus is used as a pearl oyster A method of forming a pearl by inserting a nucleus between a shell of a pearl oyster such as a shellfish, a white pearl oyster, and an Abe shellfish and the body is performed.

As another conventional method, there is known a method in which the surface of a spherical body formed of a shell is constituted by a metal or a colored material as a pearl mother nucleus (JP-A-59-20343).
No. 6).

[0004]

However, the former of such conventional methods has a problem that the number of the pearl oysters is decreasing because the pearl nucleus is formed of natural pearl oysters. is doing.

In the latter case, the surface of the spherical body is made of a metal including an alloy or a colored material, and a single metal such as gold, platinum, nickel or chromium and Since these alloys, paint coatings of colored synthetic resin paints, and the like are used, even if the biocompatibility with the tissue of the pearl oyster is increased, the degree of the compatibility has a limit. Also, since the mother nucleus used is a shell made of pearl pearl pearl shell or the like in the shape of a sphere, it has a problem associated with the decrease of natural products, as in the former case.

[0006]

[Means and Actions for Solving the Problems] Therefore, the present invention is to form a spherical mother-of-pearl nucleus of a composite material containing a calcium phosphate compound such as hydroxyapatite into a pearl oyster, Forming pearls in the pearl oyster is the solution.

At present, many shellfish distributed all over the world are composed mainly of calcium carbonate (CaCO ₃ ), but the Paleozoic shells are not It is known that calcium phosphate containing a large amount of (P) was the main component. In this way, the process in which the main component of the shell changed from calcium phosphate to calcium carbonate is due to the gradual lack of phosphorus in seawater. Therefore, calcium phosphate-based compounds having calcium phosphate as a constituent element, such as hydroxyapatite, dibasic calcium phosphate, tribasic calcium phosphate, quaternary calcium phosphate, eighth calcium phosphate, calcium pyrophosphate, and the like, have high biocompatibility with pearl oysters. it can.

Furthermore, in addition, in particular, hydroxyapatite is represented by the rational formula of Ca ₁₀ (PO ₄ ) ₆ (OH) ₂ and has the same composition as that of living bone.
Therefore, it can be said that the biocompatibility of the shellfish, which is a living body, is good even if the nucleus is put in the shellfish. By having such biocompatibility, when the pearl nucleus made of the composite material in which the resin contains hydroxyapatite is put into the pearl oyster, the nacre becomes easy to wind.

Further, since hydroxyapatite has a fluorescent property, it improves the optical characteristics of the appearance of the pearl thus formed.

This hydroxyapatite contains Ca
_It has a composition of ₁₀ (PO ₄ ) ₆ (OH) ₂ and is generally synthesized from a calcium salt and a phosphate, but the synthesis requires highly pure raw materials and complicated steps. However, Ca / P has a molar ratio of 1.4 to 1.8,
Calcium phosphate salts containing Cl, F, CO _3, etc. are easily synthesized from general calcium salts and phosphate salts, and the resulting salts have the same properties as hydroxyapatite. Can be used in the present invention.

[0011]

EXAMPLES The details of the method for forming pearls according to the present invention will be described below with reference to examples.

The present invention is characterized in that a pearl mother nucleus obtained by spherically forming a composite material in which a resin contains calcium phosphate or hydroxyapatite is formed into a pearl shell to form a pearl. is there.

The purpose of incorporating calcium phosphate or hydroxyapatite in the resin is to adjust the hardness and weight of the pearl nucleus.

The amount of calcium phosphate or hydroxyapatite added to the resin is 3% by weight or more, preferably about 5% by weight or more in consideration of the affinity for pearl oysters.

At this time, it is possible to add a small amount of titanium, zirconia, other ceramics, pigments or the like in order to adjust the color and the specific gravity.

Although any method may be used to mold the composite material into a spherical shape, injection molding is used in the embodiment. As an example of a pearl mother nucleus using this composite material, 50% by weight of hydroxyapatite calcined at 1200 ° C and 50% by weight of polymethylmethacrylate are mixed to form a sphere having a specific gravity of about 1.7 at 1200 ° C. 70% by weight of fired hydroxyapatite and 30% by weight of polopropolene were mixed to form spheres having a specific gravity of about 1.9, 20% by weight of hydroxyapatite and 58% of zirconia.
By weight, polymethylmethacrylate was mixed at 22% by weight to prepare a sphere having a specific gravity of about 2.7.

Next, this pearl mother nucleus is placed (nucleus) between the shell of the pearl oyster and the body together with the cut end of the mantle extracted from other pearl oysters, etc. Similarly, pearl oysters are raised in the sea.

The pearls formed according to this example have good optical characteristics of appearance due to the fluorescent property of hydroxyapatite and can improve aesthetics.

In the above-mentioned examples, the particle size of the pearl mother nucleus containing hydroxyapatite in the resin is 6.5.
Although the size is set to ~ 7.5 mm, the size is not limited to this, and the particle size of the pearl nucleus can be appropriately changed according to the target particle size of the pearl. If desired, it is possible to increase the particle size of the pearl nucleus to about 20 to 30 mm. And, even if the pearl particle size is increased in this way, since the hydroxyapatite contained in the core has fluorescence, even if the pearl layer on the core is thin, it does not spoil the appearance and is rather good. It is possible to obtain a nice glow.

In the above examples, the pearl mother nucleus in which fine granular hydroxyapatite is simply contained in the resin is used. However, by incorporating a pigment in hydroxyapatite, for example, pink, blue, emerald green, etc. It is also possible to form pearls with colors,
By doing so, it becomes possible to adjust the hardness and weight of the pearl nucleus. In particular, hydroxyapatite has cavities in its molecular structure and easily absorbs the pigment in the cavities, so that the addition of the pigment becomes easy.

Further, calcium pyrophosphate, tricalcium phosphate,
Even if the resin containing the eighth calcium phosphate or the like is used, similarly good pearl formation can be achieved.

The resin may be, for example, polypropylene or ABS in addition to the above polymethylmethacrylate.
Various resins such as resin and polycarbonate can be used.

As described above, the present invention is capable of various design changes accompanying the gist of the configuration.

The test examples of the present invention are shown below.

Example 1) 20% by weight of hydroxyapatite, 60% by weight of zirconia and 20% by weight of polypropylene were mixed to prepare beads having a specific gravity of about 2.7 and a diameter of about 7 mm.

Example 2) 200 beads produced in Example 1 were inoculated into pearl oysters and tested. After 6 months, the death rate, the appearance rate of enucleation, the pearl production rate of lower or higher, and the pearl weight of the lower or higher pearl-producing pearl were measured. For comparison,
76% by weight of zirconia and 24% by weight of polypropylene
A bead having a specific gravity of about 2.7 and a diameter of about 7 mm was prepared by mixing with, and the same test was performed.

[0027]

[Table 1]

From the above results, it can be seen that the mortality of shellfish, enucleation, pearl formation rate, and weight are all higher than those of the comparative examples, and that the effect of hydroxyapatite is high.

[0029]

As is clear from the above description, according to the method for forming pearls of the present invention, since the pearl nucleus having a good affinity for the pearl oyster is used, the pearl layer has an effect of being easily wound. In addition, it has an effect of surely forming pearls having a good appearance and easily controlling the particle size.

Claims (2)

[Claims] 1. A pearl formation comprising forming a spherical pearl nucleus made of a composite material containing a calcium phosphate compound in a resin into a pearl oyster to form a pearl in the pearl oyster. Method. 2. A method for forming pearls, wherein a pearl mother nucleus formed by spherically forming a composite material containing hydroxyapatite in a resin is put into a pearl oyster to form a pearl in the pearl oyster. .