JP6759877B2 - Precious Metal Clay Regeneration Liquid and Precious Metal Clay Regeneration Method - Google Patents

Description

The present invention relates to a noble metal clay regenerating liquid and a method for regenerating noble metal clay.

Precious metal clay is known as a clay-like composition containing a fine powder of a noble metal. The noble metal clay can be formed into a noble metal model by forming it into a desired shape, drying it to form a solidified product, and then firing it to sinter the fine powder of the noble metal. Precious metal clay has the advantage that it can be freely shaped by hand in the same way as ordinary clay, and it is relatively easy to manufacture precious metal shaped objects of various shapes. For this reason, precious metal clay is widely used as a material for accessories such as rings and pendant heads and arts and crafts.

Precious metal clay is generally a composition containing a fine powder of a noble metal, an organic binder, and water as basic components. Patent Document 1 describes silver clay consisting of fine silver powder, an organic binder, fats and oils, a surfactant, and the rest of water.

Japanese Patent No. 4265127

By the way, since the molding of the precious metal clay is mainly performed by hand, the precious metal clay may be dried by the heat transmitted from the hand and the precious metal clay may be solidified in the middle of the work. In addition, when the leftover precious metal clay is stored for a long period of time, it may gradually dry and solidify.

As a method of regenerating the solidified precious metal clay as the precious metal clay in the original clay state that can be formed, a method of bringing the solidified precious metal clay into contact with water and re-kneading it can be considered. However, since the noble metal used for the noble metal clay is a fine powder and the noble metal clay solidified product is dense, it is difficult for water to penetrate into the inside. Therefore, when only water is brought into contact with the noble metal clay solidified product, the noble metal clay is dissolved and dispersed in the water accumulated on the surface portion of the noble metal clay solidified product, and a viscous paste is easily formed. The viscous paste is highly sticky and easily adheres to human hands. Therefore, it is difficult to form the precious metal clay produced by the viscous paste.

The present invention has been made in view of the above-mentioned circumstances, and the precious metal clay solidified product can be regenerated as a precious metal clay in a formable clay state without forming a viscous paste. It is an object of the present invention to provide a method for regenerating a regenerating liquid and a precious metal clay.

In order to solve the above problems, the noble metal clay reclaimed liquid of the present invention contains water and liquid paraffin containing a chain saturated hydrocarbon having 20 or more carbon atoms , and the amount of the liquid paraffin with respect to 100 parts by mass of the water. Is contained in a ratio of 0.12 parts by mass or more and 60 parts by mass or less.

According to the precious metal clay reclaimed liquid having this structure, water and liquid paraffin are contained in a ratio in which the amount of the liquid paraffin with respect to 100 parts by mass of the water is in the range of 0.12 parts by mass or more and 60 parts by mass or less. , It becomes easy to penetrate inside the precious metal clay solidified material. Therefore, by bringing the above precious metal clay reclaimed liquid into contact with the noble metal clay solidified material, the noble metal clay regenerated liquid can be permeated into the noble metal clay solidified material without forming a viscous paste, and the noble metal clay can be permeated. The solidified product can be regenerated as a clay-like precious metal clay that can be formed.

The precious metal clay reclaimed liquid preferably further contains a lower alcohol of 5% by mass or more and 50% by mass or less with respect to the total amount. In this case, the water in the precious metal clay reclaimed liquid and the liquid paraffin are less likely to be phase-separated, and the composition of the noble metal clay regenerated liquid becomes uniform over a long period of time.

The precious metal clay reclaimed liquid preferably further contains a surfactant of 0.1% by mass or more and 30% by mass or less with respect to the total amount. In this case, the water in the precious metal clay reclaimed liquid and the liquid paraffin are less likely to be phase-separated, and the composition of the noble metal clay regenerated liquid becomes uniform over a long period of time.

In the method for regenerating noble metal clay of the present invention, water and liquid paraffin containing chain saturated hydrocarbon having 20 or more carbon atoms are added to the noble metal clay solidified product, and the amount of the liquid paraffin is 0 with respect to 100 parts by mass of the water. It is characterized by contacting at a ratio of 12 parts by mass or more and 60 parts by mass or less.

According to the method for regenerating precious metal clay having this configuration, water and liquid paraffin are added to the solidified precious metal clay, and the amount of the liquid paraffin with respect to 100 parts by mass of water is in the range of 0.12 parts by mass or more and 60 parts by mass or less. Since the contact is carried out at a ratio of 2), water and liquid paraffin easily permeate into the noble metal clay solidified product. Therefore, by utilizing the above-mentioned regeneration method, water and liquid paraffin can be permeated into the noble metal clay solidified product without generating a viscous paste formation, and the noble metal clay solidified product is formed. It becomes possible to regenerate the precious metal clay in a possible clay state.

INDUSTRIAL APPLICABILITY According to the present invention, there is provided a precious metal clay regenerating liquid and a method for regenerating precious metal clay, which can regenerate a solidified precious metal clay as a noble metal clay in a formable clay state without forming a viscous paste. be able to.

It is an external photograph of the regenerated silver clay material which was regenerated by contacting the solidified silver clay with the mixed solution of Example 1 of this invention. It is an external photograph of a regenerated silver clay product which was regenerated by contacting water with a solidified silver clay product. It is an external photograph of the regenerated silver clay material which was regenerated by contacting liquid paraffin with the solidified silver clay.

The precious metal clay reclaimed liquid of the present embodiment contains water and liquid paraffin at a ratio in which the amount of the liquid paraffin with respect to 100 parts by mass of the water is in the range of 0.12 parts by mass or more and 60 parts by mass or less. The amount of liquid paraffin with respect to 100 parts by mass of water is preferably in the range of 0.5 parts by mass or more and 15 parts by mass or less. If the amount of liquid paraffin is too low, a viscous paste is likely to form when in contact with the precious metal clay solidified. On the other hand, if the amount of liquid paraffin is too large, it becomes difficult to permeate the noble metal clay solidified product, and it may be difficult to regenerate the noble metal clay that can be formed.

Liquid paraffin is a mixture of chain saturated hydrocarbons. The chain saturated hydrocarbon contained in liquid paraffin generally has 20 or more carbon atoms. The chain saturated hydrocarbon in the liquid paraffin may be linear or may have a branch. As the liquid paraffin, either light liquid paraffin or heavy liquid paraffin can be used. The content of liquid paraffin with respect to the total amount of the precious metal clay reclaimed liquid is preferably in the range of 0.1% by mass or more and 30% by mass or less, and preferably in the range of 0.5% by mass or more and 10% by mass or less. Is more preferable. The amount of liquid paraffin in the precious metal clay reclaimed liquid can be measured, for example, by using a gas chromatograph method.

The water and liquid paraffin in the noble metal clay reclaimed liquid may be separated into an aqueous phase and an oil phase (liquid paraffin phase), or may form an emulsion. When the noble metal clay reclaimed liquid is separated into an aqueous phase and an oil phase, it is preferable to mix them well so that the oil phase and the aqueous phase are uniformly dispersed in each other before use.

The precious metal clay reclaimed liquid of the present embodiment may contain a lower alcohol. The lower alcohol is preferably a monohydric alcohol having a carbon number in the range of 1 to 5. Examples of lower alcohols include methanol, ethanol, 1-propanol and 2-propanol. Lower alcohols contribute to the formation of emulsions of water and liquid paraffin. The content of the lower alcohol is preferably in the range of 5% by mass or more and 50% by mass or less with respect to the total amount of the precious metal clay reclaimed liquid. If the content of the lower alcohol is too low, it becomes difficult for water and liquid paraffin to form an emulsion, and it becomes easy to separate the aqueous phase and the oil phase. On the other hand, if the content of the lower alcohol is too large, it becomes difficult for the precious metal clay reclaimed liquid to permeate into the noble metal clay solidified product, and it may be difficult to obtain a regenerated precious metal clay that can be shaped.

The precious metal clay reclaimed liquid of the present embodiment may contain a surfactant. The type of surfactant is not particularly limited, and any of a cationic surfactant, an anionic surfactant and a nonionic surfactant can be used. Surfactants contribute to the formation of emulsions of water and liquid paraffin. The content of the surfactant is preferably in the range of 0.1% by mass or more and 30% by mass or less with respect to the total amount of the precious metal clay reclaimed liquid. If the content of the surfactant is too low, it becomes difficult for water and liquid paraffin to form an emulsion, and it becomes easy to separate the aqueous phase and the oil phase. On the other hand, if the content of the surfactant is too large, it may be difficult for the precious metal clay reclaimed liquid to permeate into the noble metal clay solidified product, and it may be difficult to obtain a regenerated precious metal clay that can be shaped.

The precious metal clay reclaimed liquid of the present embodiment preferably contains a lower alcohol and a surfactant in an amount in the above range. In addition, the precious metal clay reclaimed liquid of the present embodiment may further contain additives such as an emulsifier, a defoaming agent, a viscosity modifier, a stabilizer for liquid paraffin (for example, an antioxidant), and a fragrance.

In the method for regenerating precious metal clay of the present embodiment, water and liquid paraffin are added to the solidified precious metal clay, and the amount of the liquid paraffin with respect to 100 parts by mass of the water is in the range of 0.12 parts by mass or more and 60 parts by mass or less. It is characterized in that it is brought into contact at a certain ratio. The amount of liquid paraffin with respect to 100 parts by mass of water is preferably in the range of 0.5 parts by mass or more and 15 parts by mass or less.

Water and liquid paraffin are preferably brought into contact with the noble metal clay solidified product as the above-mentioned noble metal clay regenerated liquid. The amount of the noble metal clay reclaimed liquid to be brought into contact with the noble metal clay solidified material cannot be uniformly determined because it varies depending on factors such as the size and shape of the noble metal clay solidified material, but is generally 0 with respect to 100 parts by mass of the noble metal clay solidified material. .1 part by mass or more and 50 parts by mass or less, preferably 0.1 part by mass or more and 20 parts by mass or less. The noble metal clay reclaimed liquid is preferably brought into contact with the entire surface of the noble metal clay solidified product.

It is preferable that the precious metal clay solidified product in which water and liquid paraffin are brought into contact with each other is placed in a closed container and allowed to stand so that the water does not volatilize, so that the precious metal clay regenerated liquid permeates the inside of the precious metal clay solidified product. The standing time is usually 30 minutes or more and 24 hours or less. The solidified precious metal clay is softened by the permeation of the reclaimed precious metal clay liquid. By kneading and homogenizing the softened precious metal clay solidified material, the precious metal clay solidified material is regenerated as a formable clay state of precious metal clay. The kneading may be performed by human hands, or a mortar and pestle may be used.

In the method for regenerating precious metal clay of the present embodiment, water and liquid paraffin may be separated and brought into contact with the solidified precious metal clay. When the water and the liquid paraffin are brought into contact with each other separately, the water may be brought into contact with the liquid paraffin, or the liquid paraffin may be brought into contact with the water after being brought into contact with the water. However, if the mixture is brought into contact with the noble metal clay solidified liquid as a mixed liquid containing water and liquid paraffin (precious metal clay regenerated liquid), the water and the liquid paraffin easily permeate into the noble metal clay solidified product, and the noble metal clay solidified product. It is preferable because the time until the clay softens can be shortened.

According to the method for regenerating precious metal clay of the present embodiment, the regenerated precious metal clay can be easily formed by hand, and thus can be used as a material for accessories such as rings and pendant heads and arts and crafts. ..

(Example 1)
Water, liquid paraffin, ethanol, and a surfactant were mixed so as to have the compositions shown in Table 1 below to prepare a mixed solution (silver clay regenerated solution) of Examples 1 to 15 of the present invention and Comparative Examples 1 and 2. .. As the liquid paraffin, liquid paraffin manufactured by Kishida Chemical Co., Ltd. was used in Examples 1 to 13 of the present invention and Comparative Examples 1 and 2. In Example 14 of the present invention, liquid paraffin: P-60 manufactured by MORESCO Corporation was used. In Example 15 of the present invention, liquid paraffin: HYCOAL M-352 manufactured by Kaneda Co., Ltd. was used. Reference Example 1 is water alone, and Reference Example 2 is liquid paraffin (manufactured by Kishida Chemical Co., Ltd.) alone.

(Amount of liquid paraffin per 100 parts by mass of water)
The amount (parts by mass) of liquid paraffin with respect to 100 parts by mass of water in the regenerated silver clay liquid was calculated from the composition of the regenerated silver clay liquid. The results are shown in Table 1.

(Presence / absence of phase separation)
It was visually observed whether or not the regenerated silver clay was phase-separated into two phases, an aqueous phase and an oil phase (liquid paraffin phase). The one that did not undergo phase separation when 1 hour had passed since the silver clay regenerated liquid was allowed to stand was designated as "A", and the one that did not undergo phase separation within 30 minutes or more and 1 hour or less after being allowed to stand was designated as "B". , And the phase separated in less than 30 minutes after being allowed to stand was designated as "C". The results are shown in Table 1.

(Evaluation of recycled silver clay)
Commercially available silver clay (PMC Flex, manufactured by Mitsubishi Materials Corporation) was prepared and molded into a cube (length: 5 mm, width: 5 mm, thickness 5 mm). Next, this silver clay molded product was heated at a temperature of 80 ° C. for 24 hours and dried to prepare a solidified silver clay product.
The silver clay solidified product was brought into contact with the silver clay regenerated liquid to regenerate the silver clay solidified product, and the obtained regenerated silver clay product was evaluated for its formability and adhesiveness by the following methods. The results are shown in Table 1.

[Evaluation of the possibility of modeling]
10 g of the solidified silver clay was placed in a plastic case. Next, 0.5 g of the silver clay reclaimed liquid was added little by little so as to come into contact with the entire surface of the solidified silver clay. Then, the plastic case was covered and allowed to stand at room temperature for 6 hours. After 6 hours, the lid was opened and the solidified silver clay was kneaded by hand to evaluate the propriety of modeling. Those that can be shaped by hand and that do not produce a viscous paste are considered "excellent". A small amount of viscous paste was produced, but those that could be shaped by hand were considered "good". Those that produced a large amount of viscous paste and were difficult to model by hand were classified as "OK". Those that could not be modeled by hand were designated as "impossible".

Further, an external photograph of the regenerated silver clay produced by contacting the solidified silver clay with the regenerated silver clay liquid of Example 1 of the present invention, water (Reference Example 1), and liquid paraffin (Reference Example 2) was taken. The results are shown in FIGS. FIG. 1 is an external photograph when the mixed solution of Example 1 of the present invention is used, FIG. 2 is an external photograph when water (Reference Example 1) is used, and FIG. 3 is a liquid paraffin (Reference Example 2). ) Is an external photograph when used.

[Evaluation of adhesion]
5 g of the solidified silver clay was placed in a mortar and pestle and crushed to obtain a solidified silver clay powder. Next, 0.5 g of the silver clay regenerated liquid was put into a mortar, and the silver clay solidified powder and the silver clay regenerated liquid were mixed with a pestle. The entire amount of the obtained mixture was sandwiched between two polypropylene films and pressure-molded to a thickness of 1 mm. Then, the film was peeled off from the mixture, and the total amount of the mixture adhering to the two polypropylene films was measured. When the total amount of the mixture adhering to the film was less than 0.3 g, it was designated as "A", and when the total amount of the mixture was 0.3 g or more and less than 0.5 g, it was designated as "B". The total amount of the above was 0.5 g or more and was designated as “C”. In addition, the evaluation of adhesiveness was not carried out for those that were judged as "impossible" in the above-mentioned evaluation of the possibility of modeling.

From the evaluation results of the applicability and adhesiveness of Reference Example 1 and the photograph of FIG. 2, the regenerated silver clay product regenerated by bringing only water into contact with the solidified silver clay product was formed by forming a viscous paste. It was confirmed that it was difficult and highly adhesive.
From the evaluation result of the feasibility of modeling in Reference Example 2 and the photograph in FIG. 3, the liquid paraffin does not permeate the silver clay solidified product, and when only the liquid paraffin is brought into contact with the silver clay solidified product, a regenerated silver clay product that can be formed. It was confirmed that it was difficult to obtain.

Since the amount of liquid paraffin in the regenerated silver clay liquid of Comparative Example 1 was small, it is considered that the regenerated silver clay product produced a viscous paste, was difficult to form, and had high adhesiveness.
Since the amount of liquid paraffin in the regenerated silver clay liquid of Comparative Example 2 was large, it is considered that a regenerated silver clay product that could be formed could not be obtained without penetrating into the solidified silver clay.
On the other hand, the regenerated silver clay liquids of Examples 1 to 15 of the present invention easily penetrated into the solidified silver clay and penetrated into the solidified silver clay, so that the regenerated silver clay product was easy to form. Moreover, it is considered that the adhesiveness is low. Further, from the results shown in Table 1, the amount of liquid paraffin with respect to 100 parts by mass of water was in the range of 0.5 parts by mass or more and 15 parts by mass or less, and the amount of lower alcohol was 5% by mass or more with respect to the total amount. The silver clay reclaimed liquid of Examples 1, 5 to 8, 14 and 15 of the present invention containing in the range of 50% by mass or less and containing the surfactant in the range of 0.1% by mass or more and 30% by mass or less with respect to the total amount. It can be seen that is particularly excellent in terms of the formability and adhesion of the regenerated silver clay regenerated product.

(Example 2)
10 g of the solidified silver clay was placed in a plastic case. Next, 0.49 g of water and 0.01 g of liquid paraffin were added little by little in this order so as to come into contact with the entire surface of the solidified silver clay. Then, the plastic case was covered and allowed to stand at room temperature for 6 hours. After 6 hours, the lid was opened and the solidified silver clay was kneaded by hand.
As a result, the solidified silver clay could be regenerated as silver clay in a clay state that can be shaped by hand.

Claims (4)

The ratio of water and liquid paraffin containing a chain saturated hydrocarbon having 20 or more carbon atoms so that the amount of the liquid paraffin is 0.12 parts by mass or more and 60 parts by mass or less with respect to 100 parts by mass of the water. A noble metal clay reclaimed liquid characterized by containing. 5 wt% or more based on the total amount, see contains 50 mass% or less of a lower alcohol, the lower alcohol is noble clay regeneration solution according to claim 1 carbon number of monohydric alcohol in the range of 1 to 5 .. 0.1 wt% or more based on the total amount, see containing 30 mass% of a surfactant, the surfactant cationic surfactant, either anionic surfactant and a nonionic surfactant precious metal clay regenerant according to one claim 1 or claim 2. Water and liquid paraffin containing chain saturated hydrocarbons having 20 or more carbon atoms are added to the noble metal clay solidified product, and the amount of the liquid paraffin with respect to 100 parts by mass of the water is 0.12 parts by mass or more and 60 parts by mass or less. A method for regenerating precious metal clay, which comprises contacting the clay at a ratio within the range of.