JPH0149677B2 - - Google Patents

Description

[Detailed description of the invention]

``Purpose'' (Industrial Application Field) The present invention relates to a pretreatment method for artificially coloring natural gemstones, and more particularly to a pretreatment method using reduced pressure water sealing for artificially coloring natural gemstones such as agate. (Prior art) High-quality natural gemstones such as jade, opal, turquoise, and agate are used as they are for jewelry and decoration, while jade, opal, and most agate, which are of lesser quality and can be colored, are used as is. The raw stone is made by using the microscopic microscopic pores that it has built in, and after infiltrating these pores with various coloring inorganic salt aqueous solutions, it is baked in an electric furnace and artificially colored into red, green, or other desired colors. It was widely used for jewelry and decoration. Also, there are very few naturally produced agates that have the unique beautiful colors that can be used for decoration, and most of them are milky-white slagstones. The coloring process for these natural gemstones requires a relatively long time. In particular, agate rough stone is special public 43-17656
As stated in the publication No. (Artificial coloring method of agate using hydrothermal method), its main component is silicon dioxide (SiO ₂ ),
It does not have a precise crystal shape, but has a network structure, which is a characteristic of _SiO2 molecules, and is considerably distorted due to changes in the production process conditions, the introduction of impurities, etc., and there are countless voids between the molecular lattices, resulting in a striped pattern as a whole. The size of the microscopic pores also differs locally, and the specific gravity is
It fluctuates from 2.1 to 2.0. The conventional coloring method is to roughly divide the color into the desired size,
Place raw stones such as agate into small pieces in an aqueous solution of various inorganic salts in the desired color (for example, an aqueous solution of ferric nitrate as a red artificial coloring agent, an aqueous solution of chromic anhydride as a green artificial coloring agent, etc.) in a container. Soak,
The aqueous coloring solution is allowed to penetrate into the pores of the rough stone while keeping it as it is. In this case, depending on the type of rough stone itself, there are rough stones that are easy to color and rough stones that are difficult to color, and there are also rough stones that can be immersed in an aqueous solution for a short time and others that require a long time. This is because there are differences in the state of existence of microscopic voids, and depending on the type of colorant inorganic salt aqueous solution used, there are some types that are easy to color and others that are difficult to color. Therefore, some types of inorganic salts require a long time to be immersed in an aqueous solution, and this is due to the slow rate of component diffusion of the inorganic salt aqueous solution. Therefore, depending on the type of agate rough stone and the combination of the inorganic salt aqueous solution for coloring, there will be a difference in the time required for the aqueous solution to penetrate into the fine pores of the rough stone and for the components to diffuse.
Agate requires soaking time ranging from weeks to months, and is also affected by changes in temperature, requiring twice or more soaking time in winter than in summer. As described above, each step of artificially coloring agate etc. is easy, but the conventional methods are extremely inefficient because the immersion time in the inorganic salt aqueous solution is considerably long. In view of the above-mentioned drawbacks, the present invention has been developed to speed up the penetration rate in an aqueous solution of inorganic salts for coloring when coloring raw natural gemstones such as agate to a desired color, thereby significantly shortening the immersion time. This paper relates to a pretreatment method for natural gemstones such as agate by sealing in vacuum water to improve the efficiency of artificial coloring methods. Therefore, the gist of this invention is that when artificially coloring a natural gemstone such as agate containing microscopic microscopic voids by immersing it in an aqueous solution of inorganic salts for coloring, the gemstone is cut to a desired size before being subjected to oxidation treatment. The microscopic pores of the material are maintained in a reduced pressure state using a vacuum tank and a vacuum pump, and the conventional coloring method is carried out in a state in which the reduced pressure state is sealed with water. Next, an example in which this invention method is applied to agate will be explained with reference to the attached drawings. The vacuum tank 1 has a tank body 2 made of transparent glass, which has a hollow cylindrical part 3 protruding from a desired location around the periphery and a horizontal flange 4 at the upper end thereof.
A hollow cylindrical portion 6 is provided protruding from the center of the ceiling, and a similar horizontal flange 7 is provided at the lower end in contact with the horizontal flange.
It consists of a transparent glass upper lid 5 having It shall have been processed to fit. A rubber stopper 8 horizontally passing through a pipe 9 having a horizontal vacuum valve 10 at the outer end is tightly fitted into the hollow cylindrical portion 3 of the main body 2, and a U-shaped moisture remover 12 is fitted into the pipe through the rubber pipe 11. and connect the U
A barometer 13, an air introduction bottle 14 with an air introduction valve 15 on the top, a vacuum oil pump 17 with an oil backflow prevention pin 16 and an exhaust pipe 18 on the top are sequentially connected to the rubber pipe 11 to the water remover.
Connect via. Next, a pipe 19 having an upward vacuum valve 21 at the top and a water tank 20 connected to the top is passed through the center of the rubber stopper 8, and the rubber stopper is tightly fitted into the hollow cylindrical part 6 of the upper lid 5. do. An open-top container 22 containing a natural gemstone material 23 such as agate to be colored cut to a desired size is led to the bottom of the tank 5, and is placed on the surface of the flange 4 of the tank and the flange 7 of the top lid. After applying vacuum grease (not shown), these surfaces are brought into close contact, and the pipe 9 of the horizontal vacuum valve 10 connecting the U-shaped water remover 12 to the vacuum oil pump 17 is connected to the hollow cylindrical portion 3 of the tank. It is configured to fit tightly together with the rubber stopper 8 and further to supply water into the tank 21. First, operate the vacuum oil pump 17 to exhaust the air in the tank 1 through the exhaust pipe 18, and check the reduced pressure while observing the barometer 13 to find a degree of vacuum that is approximately 1 torr, which is between a low vacuum and a medium vacuum. When this temperature is reached, prepare for water injection by pouring the required amount of water at approximately 2 to 5°C separately prepared into the water tank 20, which is combined with the top lid 5, and immediately close the horizontal valve 10 of the tank 1, and then turn on the vacuum oil. Stop the pump 17, open the air introduction valve 15 to introduce air, open the space between the horizontal vacuum valve 10 and the vacuum oil pump 17 to return to normal pressure, and use the oil backflow prevention pin 16 to prevent oil backflow. Immediately after this, the upward vacuum valve 21 of the upper lid 5 of the vacuum tank 1 is gradually opened to inject the water in the water tank 20 into the tank. Therefore, when the inside of the vacuum tank 1 is under reduced pressure and water is injected downward from the top through the pipe 19, the water becomes countless water droplets and falls down inside the tank, flowing downward into the top open container 22 at the bottom of the tank. material 2
3 is completely submerged in water, the upward vacuum valve 21 of the upper lid 5 is closed to stop water injection, and the horizontal vacuum valve 10 of the tank 1 is immediately opened to introduce air into the tank to create normal pressure. Material to be colored with this 2
The microscopic microscopic voids of No. 3 are surrounded by water in a reduced pressure state (the reduced pressure water-filled state of the present invention). When the material 23 is subjected to the reduced-pressure water-sealing state of the present invention, the voids in the material are completely surrounded by water under reduced pressure, and water immediately begins to infiltrate into the material voids. After several minutes, the depth of water penetration increases, and a water penetration layer is formed on the surface of the material.
Therefore, even when the material is taken out of water into the air, it remains completely wet with water, completely preventing air from entering the void for a short period of time. Therefore, when the material 23 is placed in a container (not shown) containing the desired inorganic salt aqueous solution for coloring prepared in advance, the material is surrounded by the aqueous coloring solution under reduced pressure inside the void. Then, the coloring aqueous solution starts to enter into the material voids. If the material 23 to be colored is pretreated by the reduced pressure water sealing method of the present invention and then immersed in a desired coloring inorganic salt aqueous solution, physical phenomena will be observed as compared to the conventional case where the material is immersed without any treatment. This significantly shortens the time for the coloring aqueous solution to penetrate into the voids of the material. However, as mentioned above, there are differences in the diffusion of the components of the aqueous coloring solution, but depending on the type of inorganic salt, by adding the immersion time of the material in the inorganic salt aqueous solution for the time required for each component to diffuse, a sufficient aqueous solution for coloring can be obtained. Penetration and component diffusion take place, and sufficient coloring can be obtained in the next firing process. Next, it will be explained why the inorganic salt aqueous solution for coloring is effectively permeated into the voids of the material 23 by this reduced pressure water sealing method. Water is poured into the vacuum tank 1 under reduced pressure to surround the material, but the water used has O, H, N, etc. dissolved in it.
When such water is injected into the vacuum tank 1 under reduced pressure, the solubility of the gas decreases and the gas is released, while the water becomes countless water droplets and spills downward, forming white streaks and causing the material to It falls into the container 22 containing the water and gradually begins to accumulate, generating bubbles from the bottom and side walls of the accumulated water.The bubbles rise through the water and gradually increase in volume until they reach the water surface and burst, causing a boiling state. gas continues to be released. When the material is completely submerged in water, close the upward vacuum valve 21 of the upper lid 5 to stop water injection, and immediately close the horizontal vacuum valve 10 of the vacuum tank 1.
The release of gas from the water stops during the process of opening the tank and introducing air into the tank to return it to normal pressure. As mentioned above, gas is released from the water used, which may affect the reduced pressure state in the voids of the material 23 by the reduced pressure water sealing method, but the amount of gas dissolved in the water, the amount of water used, and the vacuum tank 1 Considering the internal volume of the vacuum, the effect is small and can be ignored when operating at a low vacuum of about 1 Torr and medium vacuum, as in the case of the method of this invention, regardless of the case of operation at a high degree of vacuum. However, in the water sealing method, it is necessary to use only the necessary amount of low-temperature water with a high gas solubility and to operate quickly to keep gas release to a minimum. When the water is injected into the vacuum tank 1, which is maintained at a reduced pressure using this reduced-pressure water sealing method, the gas dissolved in the water is released as described above, and at the same time, the water vaporizes until the vapor pressure corresponds to the temperature of the water used. continues to become
A similar process occurs inside the voids of the material 23. At this time, water loses heat of vaporization, so if the temperature of the water used is extremely close to 0°C and water is poured into the tank,
It is better not to lower the water temperature too much, as water droplets may turn into ice. The vapor pressure of water is 4.579 mm of mercury at 0℃ and at 10℃.
9.205 mm and 17.51 mm at 20°C, so the temperature of the water used is much lower, the less steam will be generated, and the formation of a water permeable layer that prevents air from entering the surface of the material 23 will be achieved quickly. Furthermore, in consideration of suppressing gas release from the water used, it is desirable to prepare a necessary amount of fairly low temperature water and promptly implement the reduced pressure water sealing method. As mentioned above, the biggest influence on the penetration of an aqueous solution of inorganic salts for coloring is the vapor pressure of water.
When carrying out the pretreatment method of the present invention, it is sufficient that the degree of vacuum is approximately 1 Torr, which is between a low vacuum and a medium vacuum. When a natural gemstone material such as agate to be colored, which has been pretreated using this vacuum water sealing method, is immersed in an aqueous inorganic salt solution for coloring of the desired color, the aqueous solution begins to penetrate into the material, and the conventional pretreatment is completed. Penetration is completed at a significantly faster rate than when immersing materials that are not soaked. The components also diffuse from the moment the aqueous solution begins to penetrate, but when the aqueous solution completes penetration, the component diffusion is insufficient, so it is necessary to extend the immersion time slightly to further diffuse the components. Particularly in the case of an aqueous inorganic salt solution whose components diffuse slowly, it is necessary to extend the immersion time accordingly to ensure sufficient diffusion of the components. At this time, if the inorganic salt aqueous solution has good stability, the temperature of the solution can be raised to shorten the component diffusion time.
If the solution is an inorganic salt aqueous solution that is unstable or whose components diffuse quickly, immerse it at room temperature. Considering the vapor pressure of water, it is technically not difficult to operate at a vacuum level of around 1 Torr, which is between low vacuum and medium vacuum, and there is no danger and the material can be removed in about 30 minutes. 23 can be sealed with reduced pressure water.
After that, when the material is immersed in an aqueous solution of inorganic salts for coloring, in the case of agate, due to the combination of the type of agate and the type of aqueous inorganic salts for coloring, conventional methods without pretreatment require soaking times ranging from weeks to several months. However, when treated with the reduced pressure water sealing method of the present invention, the immersion time can be shortened from several hours to several days, and the artificial coloring process can be significantly streamlined. Example I Material A: Agate cut into 5 x 30 x 40 mm, which is dark milky white to the naked eye, hardly transmits light, and exhibits a clear striped pattern. Material B: Agate that is also dark milky white and hardly transmits light. Material C: Medium milky white that slightly transmits light. Material D: Thin milky white color that transmits a considerable amount of light. Prepare the above four types of materials, operate the vacuum oil pump 17 for 20 minutes to maintain a vacuum of 5 to 7 Torr, perform the reduced pressure water sealing method, and store them in a cool place to allow water to penetrate. As a result of investigating the situation, material A
Water completely penetrated into the material within 4 hours of water immersion, material B completed water penetration within 8 hours, material C within 12 hours, and material D water penetration within 16 hours. After several hours have passed since the start of water immersion, each material is taken out and observed by shining a light from behind.Water begins to penetrate from the surface and outer periphery of the material, and the edges become translucent (semi-transparent). (I can tell that there is an object on the side, but I can't make out its shape) It becomes brighter, and the core part was milky white and the part that was difficult for light to pass through remained dark, but as time passed, it became completely translucent. It was clearly observed with the naked eye that the milky-white dark part of the core, which was difficult for light to pass through, had disappeared and water had completely passed through it. Example After applying the same vacuum water sealing method to the same material as in Example I, the cold water in the water seal was replaced with hot water and heated to nearly 100°C for several minutes, then replaced with cold water and placed in a cool place. After storage and observing the state of water penetration, material A completed water penetration within 2 hours of water immersion, material B within 4 hours, material C within 6 hours, and material D within 8 hours. It was found that water penetration was completed by immersion, and that the water penetration time of Example I could be reduced to half. If the cold water used in the vacuum water sealing method is replaced with hot water in a short period of time, the water vapor pressure within the microscopic pores within the material 23 is raised to nearly 760 mm in mercury at 100°C, and then replaced with cold water again. It is thought that the water vapor pressure within the void is rapidly reduced, causing dew to condense on the inner wall of the void and making it wet, which acts as a priming water and reduces the water penetration time by half. Example 20g of chromic anhydride and 100g of water for green coloring
An aqueous solution in which . Next, the material was immersed in an aqueous chromic acid anhydride solution and kept in a cool place, and as in Example I, material A was immersed for 4 hours and material B was immersed for 8 hours.
After confirming that penetration of the aqueous solution was completed after 12 hours for material C and 16 hours for material D, the material was wrapped in straw ash, placed in a crucible, and heated to 400°C in an electric furnace. The material taken out from the electric furnace after cooling was colored green, but when the material was broken and examined, there were color spots and the coloring was not to the same extent to the core, indicating that the component diffusion of the chromic anhydride aqueous solution was slightly insufficient. Ta. Next, the same material was similarly pretreated by the vacuum water sealing method and then immersed in an aqueous chromic acid anhydride solution as follows.

[Table] After extending the immersion time for component diffusion of materials C and D and adding the immersion time in the aqueous solution, uniform green coloring was obtained when heated to 400°C in an electric furnace. Next, the same material was pretreated by vacuum water sealing method according to the example, the cold water was replaced with boiling water, heated and boiled for several minutes, the material was replaced with cold water again, and finally it was immersed in an aqueous chromic acid anhydride solution as follows. .

[Table] Stop the immersion at the above immersion time and place it in an electric furnace for 400 minutes.
A uniform green coloration was obtained upon heating to . This coloring aqueous solution should be stored in a cool place and the components should be immersed for diffusion.
It was carried out at a constant temperature of 25°C to 30°C. Example: 100g of ferric nitrate and 100g of water for red coloring
An aqueous solution was prepared. Since the component diffusion of the ferric nitrate aqueous solution is slower than that of the chromic anhydride aqueous solution, the component diffusion immersion time was shortened by raising the liquid temperature. The same material was pretreated in the same manner as in Example I by vacuum water sealing, then immersed in an aqueous ferric nitrate solution and stored in a cool place. After completion of the aqueous solution infiltration, the liquid component diffusion immersion was carried out at a constant temperature of 65° C. to 70° C. as shown in the table below.

[Table] After immersing the material in an aqueous solution for 12 to 72 hours, the material turns bright red when wrapped in straw ash, placed in a crucible, heated at 300℃ in an electric furnace, and cooled. Even when the material was colored and examined by breaking it, uniform coloration was obtained with no color spots. When the liquid component diffusion immersion is carried out at a constant temperature of 25℃ to 30℃, the temperature is 65℃.
Twice the soaking time was required than when soaking at a constant temperature of ~70°C.

[Brief explanation of drawings]

FIG. 1 is an overall schematic diagram of an apparatus for implementing the reduced pressure water sealing method according to the present invention, and FIG. 2 is an enlarged sectional view of the vacuum tank portion of FIG. 1. 1... Vacuum tank; 9, 19... Pipe; 10... Horizontal vacuum valve; 12... U-shaped moisture remover; 13
...Barometer; 14...Air introduction bottle; 15...Bottle 14
air valve; 16... oil backflow prevention bottle; 17... vacuum oil pump; 18... exhaust pipe of pump 17; 20... water tank; 21... upward vacuum valve of tank 20; 22... top open container; 23... material.

Claims (1)

[Claims] 1. When artificially coloring a natural gemstone material such as agate that contains microscopic pores with an aqueous solution of coloring inorganic salts, the material pores are held in a reduced pressure state, and the material pores are sealed in a reduced pressure state with water before treatment. A vacuum water sealing pretreatment method for artificially coloring natural gemstones such as agate.