Preparation method of gold mud powder and gold mud powder

Abstract

The present application provides a method for preparing gold mud powder and the gold mud powder, and relates to the technical field of preparation of precious metal powder colloids. The present invention uses spherical gold powder as a raw material, firstly mixes the spherical gold powder with the additives polyvinyl alcohol and gelatin for ball milling, washes with deionized water, and dries to obtain flaky gold powder; then the flaky gold powder is evenly mixed with an adhesive and a non-ionic surfactant, and dried to obtain gold mud powder. The present application adds two organic additives to aid grinding during grinding, and the two synergistically adjust the dispersibility of the gold powder in the ball milling liquid, effectively avoiding the cold welding phenomenon caused by the soft texture of the gold powder during the grinding process and the gold powder adhesion and agglomeration phenomenon caused by the viscosity and insufficient lubricity of the ball milling liquid. In addition, the present application reduces the surface tension of the water in the gold slurry by adding a non-ionic surfactant, so that the gold mud powder can be directly applied to the smooth surface of the object after being mixed with water, which not only simplifies the gold brushing process, but also expands the application range of the gold mud powder.

Description

Technical Field

[0001] The invention relates to the technical field of preparation of precious metal powder colloid particles, and in particular to a preparation method of gold mud powder for decoration and the gold mud powder. Background Art

[0002] Gold is one of the rarest and most precious metals in the world. It not only has the characteristics of high density, high chemical stability, soft texture, excellent ductility, non-oxidation and corrosion resistance, but also has a bright golden color. It can maintain good luster and performance in a variety of environments and is easy to process. It is widely used in jewelry making, Kintsugi restoration, gilding of Buddha statues, thangka, sutra writing, and Maki-e and other arts and crafts decoration fields.

[0003] In the aforementioned field of arts and crafts decoration, common processing methods include gilding, brushing gold, gilding, gold plating, and the like. Among them, brushing gold refers to brushing the surface of a Buddha statue with gold powder or gold paste to form a golden coating, and gold mud pigment (gold mud powder) is an important raw material for preparing gold paste. In traditional processes, gold mud powder is mainly prepared by manually kneading a mixture of gold foil and animal glue, washing it with a large amount of water, and drying it. The labor and raw material costs of this preparation method are relatively high, especially the gold foil raw material used in the preparation process needs to be repeatedly hammered manually, and the preparation process includes twelve steps, which is very complicated and lengthy. In addition, the traditional gold brushing process is also relatively complicated, and water-soluble gold mud powder is difficult to directly apply on the smooth surface of an object. The object needs to be cleaned, polished, and other pretreatments in advance before it can be evenly brushed.

[0004] In view of this, it is necessary to design a preparation method of gold mud powder and gold mud powder to solve the above problems. Summary of the Invention

[0005] In view of the technical problems existing in the background art, the present application provides a method for preparing gold mud powder and the gold mud powder. Spherical gold powder with a particle size of 2-4 μm and a purity greater than 99% is used as the raw material. The spherical gold powder is first mixed with the additives polyvinyl alcohol and gelatin and ball-milled to produce flaky gold powder. The flaky gold powder is then mixed with a binder and a nonionic surfactant to produce the gold mud powder. The gold mud powder prepared by this method can be directly applied to smooth surfaces of objects after being mixed with water, without the need for pre-polishing the objects. It has low cost, simple and convenient operation, a wide range of applications, and has been implemented for large-scale production.

[0006] In a first aspect, the present invention provides a method for preparing gold mud powder, which is prepared using spherical gold powder, comprising the following steps:

[0007] S1, mixing the spherical gold powder with a polyvinyl alcohol solution and a gelatin solution, adding zircon balls and milling the mixture, filtering the mixture, washing the mixture with deionized water until the gold powder solution is clear, and drying the mixture to obtain flaky gold powder;

[0008] S2, uniformly mixing the flaky gold powder obtained in step S1 with a binder and a non-ionic surfactant, and drying the mixture to obtain gold mud powder.

[0009] Furthermore, the particle size of the spherical gold powder is 2-4 μm, and the purity is greater than 99%.

[0010] Furthermore, in step S2, the nonionic surfactant is polyethylene glycol monooctylphenyl ether, and the amount of polyethylene glycol monooctylphenyl ether is 0.1-1% of the mass of the flaky gold powder.

[0011] Furthermore, in step S1, the concentration of the polyvinyl alcohol solution is 0.1-0.3 g / mL, and each gram of spherical gold powder is mixed with 8-20 mL of the polyvinyl alcohol solution.

[0012] Furthermore, in step S1, the concentration of the gelatin solution is 0.1-0.3 g / mL, and each gram of spherical gold powder is mixed with 8-20 mL of gelatin solution.

[0013] Furthermore, in step S1, the ratio of the spherical gold powder to the zircon balls is 1:(40-60); in step S1, the rotation speed of the ball mill is 150-200 r / min, and the ball milling time is 3-5 h.

[0014] Furthermore, in step S2, the adhesive is a gelatin solution, and the concentration of gelatin is 0.1-0.3 g / mL; in step S2, each gram of flaky gold powder is mixed with 0.08-0.2 mL of gelatin solution.

[0015] Furthermore, in step S1 and step S2, the drying temperature is 60-90°C.

[0016] Furthermore, step S2 also includes adding water to the mixture of flaky gold powder, adhesive and non-ionic surfactant to adjust the gold paste to a viscous state, dipping the viscous gold paste with a brush, allowing the gold paste to naturally drip onto the polyethylene plastic plate under the action of gravity to form small droplets, and then drying.

[0017] In a second aspect, embodiments of the present application provide a gold mud powder, prepared according to any of the aforementioned technical solutions, for use in gilding Buddhist statues, thangkas, sutra writing, and maki-e painting. The gold mud powder does not require prior polishing of the object; it can be applied directly to the smooth surface of the object after adding water to make the powder viscous.

[0018] The beneficial effects of the present invention are:

[0019] The present application provides a method for preparing gold mud powder and the gold mud powder. Spherical gold powder with a particle size of 2-4 μm and a purity greater than 99% is used as the raw material. The spherical gold powder is first mixed with polyvinyl alcohol and gelatin as additives and ball-milled to produce flaky gold powder. The flaky gold powder is then mixed with a binder and a nonionic surfactant to produce the gold mud powder. This method has a high degree of mechanization and a short process. The prepared gold mud powder can be directly applied to a smooth surface of an object after being mixed with water, without the need for pre-polishing the object. The method also has low cost, simple and convenient operation, and a wide range of applications, enabling large-scale production.

[0020] (1) The simultaneous addition of polyvinyl alcohol and gelatin during the ball milling process of the present application helps to regulate the dispersion of the gold powder in the ball milling liquid, thereby producing flaky gold powder with regular shape and uniform dispersion. The polyvinyl alcohol molecule contains a large number of hydroxyl groups, which can increase the hydrophilicity of the gold powder, allowing the gold powder to be fully dispersed and avoiding the cold welding phenomenon caused by the gold powder being too soft. The addition of gelatin as an organic additive can increase the viscosity of the ball milling liquid, improve the lubricity, and avoid uneven dispersion of the gold powder due to adhesion or agglomeration.

[0021] (2) The adhesive of the present application is preferably gelatin, and the nonionic surfactant is preferably polyethylene glycol monooctylphenyl ether. The polyethylene glycol monooctylphenyl ether molecule has a hydroxyl hydrophilic group at one end and an alkane hydrophobic group at the other end. The hydrophilic group can form hydrogen bonds with water molecules, forming a molecular film on the surface of the liquid. The molecular film can reduce the surface tension of the water in the gold paste, allowing the gold paste to be directly and evenly coated on the smooth surface of the object. This improvement not only simplifies the gold brushing process, but also broadens the application range of gold mud powder.

[0022] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] To more clearly illustrate the technical solution of this application, the following is a brief introduction to the drawings used in this application. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0024] Figure 1 This is a SEM image of the gold mud powder prepared in Example 1 of the present application;

[0025] Figure 2 This is a SEM image of the gold mud powder prepared in Example 2 of the present application;

[0026] Figure 3 This is a SEM image of the gold mud powder prepared in Example 3 of the present application;

[0027] Figure 4 This is the SEM image of the gold mud powder prepared in Comparative Example 1 of this application;

[0028] Figure 5 This is the SEM image of the gold mud powder prepared in Comparative Example 2 of this application;

[0029] Figure 6 This is a comparison diagram of the effects of brushing the gold mud powder prepared in Example 1 and Comparative Example 3 of the present application onto the surface of a smooth copper object after being prepared into gold slurry; among them, a is a brushing effect diagram of the gold mud powder prepared by Comparative Example 3, and b is a brushing effect diagram of the gold mud powder prepared by Example 1. DETAILED DESCRIPTION

[0030] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0032] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0033] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0034] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0035] In traditional craftsmanship, gold mud powder is primarily prepared by hand-kneading a mixture of gold foil and animal glue, washing it with copious amounts of water, and drying it. This preparation method incurs high labor and raw material costs, particularly as the gold foil used in the preparation process requires repeated manual hammering. The preparation process, which involves twelve steps, is complex and lengthy. Furthermore, the traditional gold-brushing process is also complex. The water-soluble gold mud powder is difficult to apply directly to smooth surfaces, requiring pre-treatment such as cleaning and polishing before even application.

[0036] In order to solve the technical problems that the preparation cost of traditional gold mud powder is high and traditional water-soluble gold mud powder cannot be directly applied on the smooth surface of objects, resulting in a complicated gold brushing process, the present application provides a preparation method of gold mud powder and gold mud powder, wherein two organic additives are added to assist grinding during grinding, and the two organic additives synergistically adjust the dispersibility of gold powder in the ball milling liquid, effectively avoiding the cold welding phenomenon caused by the soft texture of gold powder during grinding and the gold powder adhesion and agglomeration phenomenon caused by insufficient viscosity and lubricity of ball milling liquid; by adding non-ionic surfactants, the surface tension of water in the gold slurry is reduced, so that the gold mud powder can be directly applied on the smooth surface of objects after being mixed with water, which not only simplifies the gold brushing process, but also expands the application range of gold mud powder.

[0037] First, an embodiment of the present application provides a method for preparing gold mud powder, which is prepared using spherical gold powder with a particle size of 2-4 μm and a purity greater than 99%. The preparation method of spherical gold powder can be found in the Chinese patent publication number CN118682140B, which will not be repeated here.

[0038] The preparation method of the gold mud powder provided in the embodiment of the present application comprises the following steps:

[0039] S1, mixing spherical gold powder with polyvinyl alcohol solution and gelatin solution, adding zircon balls and milling, then filtering to remove the zircon balls, washing with deionized water until the gold powder solution is clear, and drying at 60-90° C. to obtain flaky gold powder.

[0040] The concentration of the polyvinyl alcohol solution is 0.1-0.3 g / mL, and each gram of spherical gold powder is mixed with 8-20 mL of the polyvinyl alcohol solution. The concentration of the gelatin solution is 0.1-0.3 g / mL, and each gram of spherical gold powder is mixed with 8-20 mL of the gelatin solution.

[0041] The simultaneous addition of polyvinyl alcohol and gelatin during the ball milling process works synergistically to regulate the dispersion of the gold powder in the milling fluid, resulting in the production of uniformly shaped, evenly dispersed gold flakes. The high hydroxyl content in polyvinyl alcohol molecules increases the hydrophilicity of the gold powder, ensuring its full dispersion and preventing cold welding, which can occur when the powder is too soft. The addition of gelatin, an organic additive, increases the viscosity of the milling fluid, improving its lubricity and preventing uneven dispersion caused by adhesion or agglomeration of the gold powder.

[0042] Preferably, the solvent of the polyvinyl alcohol solution and the gelatin solution is water.

[0043] In the embodiment of the present application, the ratio of spherical gold powder to zircon balls is 1:(40-60), the ball milling speed is 150-200 r / min, and the ball milling time is 3-5 h.

[0044] Preferably, the equipment used for ball milling is a planetary ball mill.

[0045] Preferably, the number of washings with deionized water is 6-10 times.

[0046] S2, mixing the flaky gold powder obtained in step S1 with a binder and a non-ionic surfactant, adding water to adjust the gold paste to a viscous state, and drying at 60-90°C to obtain gold mud powder.

[0047] The binder is preferably a gelatin solution having a gelatin concentration of 0.1-0.3 g / mL, and each gram of flaky gold powder is mixed with 0.08-0.2 mL of the gelatin solution. The nonionic surfactant is polyethylene glycol monooctylphenyl ether, and the amount of polyethylene glycol monooctylphenyl ether used is 0.1-1% of the mass of the flaky gold powder.

[0048] The molecule of polyethylene glycol monooctylphenyl ether has a hydroxyl hydrophilic group at one end and an alkane hydrophobic group at the other. The hydrophilic group can form hydrogen bonds with water molecules, forming a molecular film on the liquid surface. This molecular film can reduce the surface tension of the water in the gold paste, allowing the gold paste to be directly and evenly applied to the smooth surface of the object. This improvement not only simplifies the gold application process but also expands the application range of gold mud powder.

[0049] Preferably, the solvent of the gelatin solution is water.

[0050] In the embodiment of the present application, step S2 further includes dipping a brush into the viscous gold paste, allowing it to drip naturally onto a polyethylene plastic plate under gravity to form small droplets, which are then dried at 60-90°C. The resulting gold mud powder product is in the form of circular flakes with a spherical crown at the top. The flakes are uniformly sized and easy to weigh and handle.

[0051] In a second aspect, embodiments of the present application provide a gold mud powder prepared using any of the aforementioned technical solutions. This gold mud powder is used in applications such as gilding Buddha statues, thangkas, sutra writing, and maki-e painting. This gold mud powder does not require prior polishing of the object; it can be applied directly to the smooth surface of the object after adding water to make the powder viscous.

[0052] Some specific examples are listed below. It should be noted that the examples described below are exemplary and are only used to explain the present application, and should not be construed as limiting the present application. Where specific techniques or conditions are not specified in the examples, the techniques or conditions described in the literature in this area or the product specifications are used. Reagents or instruments used without manufacturer's indication are all commercially available conventional products.

[0053] Example 1

[0054] Example 1 provides a method for preparing gold mud powder, comprising the following steps:

[0055] S1. Mix 2 g of spherical gold powder with a particle size of 2-4 μm with 20 mL of 0.2 g / mL polyvinyl alcohol solution and 20 mL of 0.2 g / mL gelatin solution in a ball mill, add 100 g of zircon balls, and place the ball mill in a planetary ball mill. Mill at a speed of 150 r / min for 4 h, then filter to remove the zircon balls, wash with deionized water 8 times until the gold powder solution is clear, and dry at 80°C to obtain flaky gold powder.

[0056] S2. Weigh 2 g of flaky gold powder and mix it with 0.2 mL of 0.2 g / mL gelatin and 2 mg of polyethylene glycol monooctylphenyl ether. Add 120 μL of water until the gold paste becomes viscous. Use a brush to dip the gold paste and allow it to drip naturally onto a polyethylene plastic plate under the action of gravity to form small droplets. Dry it at 80°C to obtain bright yellow gold mud powder.

[0057] The gold mud powder prepared in Example 1 was characterized by scanning electron microscopy (SEM). Figure 1 As shown, it can be seen that the flaky gold powder in the gold mud powder has a uniform morphology. After measurement, the average size of the flaky gold powder is 7-8μm.

[0058] Example 2

[0059] Example 2 provides a method for preparing gold mud powder (scale-up test), comprising the following steps:

[0060] S1. Mix 10 g of spherical gold powder with a particle size of 2-4 μm with 100 mL of a 0.2 g / mL polyvinyl alcohol solution and 100 mL of a 0.2 g / mL gelatin solution in a ball mill, add 500 g of zircon balls, and place the ball mill in a planetary ball mill. Mill at a speed of 150 r / min for 4 h, then filter to remove the zircon balls, wash with deionized water 8 times until the gold powder solution is clear, and dry at 80°C to obtain flaky gold powder.

[0061] S2. Weigh 10 g of flaky gold powder, mix it with 1 mL of 0.2 g / mL gelatin and 10 mg of polyethylene glycol monooctylphenyl ether, then add 600 μL of water until the gold paste becomes viscous. Use a brush to dip the gold paste and allow it to drip naturally onto a polyethylene plastic plate under gravity to form small droplets. Dry it at 80°C to obtain bright yellow gold mud powder.

[0062] The gold mud powder prepared in Example 2 was characterized by scanning electron microscopy (SEM). Figure 2 As shown, it can be seen that the flaky gold powder in the gold mud powder has a uniform morphology. After measurement, the average size of the flaky gold powder is 7-8μm.

[0063] Example 3

[0064] Example 3 provides a method for preparing gold mud powder (scale-up test), comprising the following steps:

[0065] S1. Mix 25 g of spherical gold powder with a particle size of 2-4 μm with 250 mL of a polyvinyl alcohol solution with a concentration of 0.2 g / mL and 250 mL of a gelatin solution with a concentration of 0.2 g / mL in a ball mill. Then add 1250 g of zircon balls and place the ball mill in a planetary ball mill. Mill the mixture at a speed of 150 r / min for 4 h. Then filter out the zircon balls and wash the mixture with deionized water for 8 times until the gold powder solution becomes clear. Dry the mixture at 80°C to obtain flaky gold powder.

[0066] S2. Weigh 25 g of flaky gold powder, mix it with 2.5 mL of 0.2 g / mL gelatin and 25 mg of polyethylene glycol monooctylphenyl ether, then add 1.5 mL of water until the gold paste becomes viscous. Use a brush to dip the gold paste and allow it to drip naturally onto a polyethylene plastic plate under the action of gravity to form small droplets. Dry it at 80°C to obtain bright yellow gold mud powder.

[0067] The gold mud powder prepared in Example 3 was characterized by scanning electron microscopy (SEM). Figure 3 As shown, it can be seen that the flaky gold powder in the gold mud powder has a uniform morphology. After measurement, the average size of the flaky gold powder is 7-8μm.

[0068] Comparative Example 1

[0069] Comparative Example 1 provides a method for preparing gold mud powder. Compared to Example 1, this method differs in that only one grinding aid, gelatin, is used in step S1. Specifically, 2 g of spherical gold powder with a particle size of 2-4 μm is mixed with 40 mL of a gelatin solution with a concentration of 0.2 g / mL in a ball mill. 100 g of zircon balls are then added, and the ball mill is placed in a planetary ball mill. The mixture is milled at 150 r / min for 4 h, and the zircon balls are then filtered to remove the zircon balls. The mixture is then washed eight times with deionized water until the gold powder solution is clear, and then dried at 80°C to obtain flaky gold powder. The remaining details are the same as in Example 1 and are not further described here.

[0070] The gold mud powder prepared in Comparative Example 1 was characterized using a scanning electron microscope (SEM). Figure 4 As shown, it can be seen that the flaky gold powder in the gold mud powder has uneven morphology and obvious cold welding phenomenon, that is, most of it is pressed into large flakes. In subsequent applications, the size of the flaky gold powder is too large and the morphology is uneven, which may cause the surface of the gold layer obtained by brushing to have obvious granularity, affecting the use effect.

[0071] Comparative Example 2

[0072] Comparative Example 2 provides a method for preparing gold mud powder. Compared with Example 1, it differs in that only one grinding aid, polyvinyl alcohol, is used in step S1. Specifically, 2g of spherical gold powder with a particle size of 2-4μm is mixed with 40mL of a polyvinyl alcohol solution with a concentration of 0.2g / mL in a ball mill. 100g of zircon balls are added, and the ball mill is placed in a planetary ball mill. The ball mill is milled at a speed of 150r / min for 4h. The zircon balls are then filtered to remove the zircon balls. The mixture is washed with deionized water eight times until the gold powder solution is clear and then dried at 80°C to obtain flaky gold powder. The rest of the contents are the same as in Example 1 and are not repeated here.

[0073] The gold mud powder prepared in Comparative Example 2 was characterized using a scanning electron microscope (SEM). Figure 5 As shown, it can be seen that the flaky gold powder in the gold mud powder does not show obvious cold welding phenomenon, but the flaky gold powder is unevenly distributed, and a small amount of flaky gold powder is bonded together, which may cause the surface of the gold layer obtained by brushing to be rough and have poor glossiness during subsequent use.

[0074] Comparative Example 3

[0075] Comparative Example 3 provides a method for preparing gold mud powder. Compared to Example 1, this method differs in that polyethylene glycol monooctylphenyl ether is not added in Step S2. Specifically, 2g of flaky gold powder is weighed and mixed with 0.2mL of 0.2g / mL gelatin. 120µL of water is added until the gold paste becomes viscous. A brush is then applied to the gold paste, which is then allowed to drip naturally onto a polyethylene plastic plate under gravity, forming small droplets. The mixture is then dried at 80°C to obtain a bright yellow gold mud powder. All other details are the same as in Example 1 and are not further elaborated here.

[0076] The gold mud powder prepared in Comparative Example 3 cannot be directly applied to the smooth surface of an object by brushing, and the object needs to be pre-treated by polishing in advance, which not only increases the use process but also has a narrow application range.

[0077] Comparative Example 4

[0078] Comparative Example 4 provides a method for preparing gold mud powder. Compared to Example 1, this method differs in that, in step S2, the adhesive gelatin is replaced with gum arabic. Specifically, 2g of flaky gold powder is weighed, mixed with 0.2mL of 0.2g / mL gum arabic and 2mg of polyethylene glycol monooctylphenyl ether, and then 120µL of water is added until the gold paste becomes viscous. A brush is then applied to the gold paste, which is then allowed to drip naturally onto a polyethylene plastic plate under gravity, forming small droplets. The mixture is then dried at 80°C to obtain a bright yellow gold mud powder. The remaining details are the same as in Example 1 and are not further elaborated here.

[0079] The surface brightness and color of the gold mud powder prepared in Example 1 and Comparative Example 4 were characterized using a spectrophotometer. The results are shown in the table below.

[0080]

[0081] As shown in the table above, the gold mud powder prepared in Comparative Example 4 is darker and less yellow than in Example 1. This is likely because the color of the gold mud powder is affected by the color of the gum arabic. Therefore, gelatin is more suitable as a binder in the gold mud powder preparation method provided in this application.

[0082] The gold paste prepared in Example 1 and Comparative Example 3 was used to prepare the gold paste and brush the smooth surface of the copper object (white copper). 200uL of water was added to each gram of gold paste to make a thick gold paste. The brushing effect was shown in FIG. Figure 6As shown. It can be seen that the gold paste obtained by mixing the gold mud powder of Example 1 can be evenly brushed onto the object, while the gold paste obtained by mixing the gold mud powder of Comparative Example 3 quickly shrinks into an irregular shape after being brushed onto the object, making it difficult to brush evenly. This is related to the excessive surface tension of the gold paste. The molecular structure of the non-ionic surfactant polyethylene glycol monooctylphenyl ether has a hydroxyl hydrophilic group at one end and an alkane hydrophobic group at the other end. The hydrophilic group can form hydrogen bonds with water molecules, forming a molecular film on the liquid surface. The molecular film can reduce the surface tension of the water in the gold paste, allowing the gold paste to be directly and evenly coated on the smooth surface of the object.

[0083] In summary, the present application provides a method for preparing gold mud powder and gold mud powder. Spherical gold powder with a particle size of 2-4 μm and a purity greater than 99% is used as a raw material. The spherical gold powder is first mixed with the additives polyvinyl alcohol and gelatin for ball milling to prepare flaky gold powder. The flaky gold powder is then mixed with an adhesive and a non-ionic surfactant to prepare a bright yellow gold mud powder. The prepared gold mud powder is mixed with water and can be directly applied to the smooth surface of an object. The preparation method has been successfully scaled up and can process 25g of gold powder at a time. In the comparative example, when only the additive polyvinyl alcohol is used in the ball milling, the prepared flaky gold powder has obvious cold welding phenomenon; when only the additive gelatin is used in the ball milling, the prepared flaky gold powder has obvious adhesion and agglomeration phenomenon; when the adhesive gelatin is replaced with gum arabic, the color of the gold mud powder becomes darker and is not yellow enough; when the non-ionic surfactant is not added, the gold paste obtained by mixing the gold mud powder with water cannot be directly and evenly applied to the smooth surface of the object.

[0084] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are merely examples, and any embodiments having substantially the same structure and effect as the technical concept within the scope of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the present application, any other embodiments that can be conceived by those skilled in the art and that combine some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A method for preparing gold mud powder, characterized in that: The method is prepared by using spherical gold powder, comprising the following steps: S1, mixing the spherical gold powder with a polyvinyl alcohol solution and a gelatin solution, adding zircon balls and milling the mixture, filtering the mixture, washing the mixture with deionized water until the gold powder solution is clear, and drying the mixture to obtain flaky gold powder; S2, uniformly mixing the flaky gold powder obtained in step S1 with a binder and a non-ionic surfactant, and drying the mixture to obtain gold mud powder; the non-ionic surfactant is polyethylene glycol monooctylphenyl ether, and the amount of the polyethylene glycol monooctylphenyl ether is 0.1-1% of the mass of the flaky gold powder.

2. The method for preparing gold mud powder according to claim 1, wherein: The particle size of the spherical gold powder is 2-4 μm, and the purity is greater than 99%.

3. The method for preparing gold mud powder according to claim 1, wherein: In step S1, the concentration of the polyvinyl alcohol solution is 0.1-0.3 g / mL, and each gram of spherical gold powder is mixed with 8-20 mL of the polyvinyl alcohol solution.

4. The method for preparing gold mud powder according to claim 1, wherein: In step S1, the concentration of the gelatin solution is 0.1-0.3 g / mL, and each gram of spherical gold powder is mixed with 8-20 mL of gelatin solution.

5. The method for preparing gold mud powder according to claim 2, wherein: In step S1, the ratio of the spherical gold powder to the zircon balls is 1:(40-60); in step S1, the rotation speed of the ball mill is 150-200 r / min, and the ball milling time is 3-5 h.

6. The method for preparing gold mud powder according to claim 1, wherein: In step S2, the adhesive is a gelatin solution, and the concentration of gelatin is 0.1-0.3 g / mL; in step S2, each gram of flaky gold powder is mixed with 0.08-0.2 mL of gelatin solution.

7. The method for preparing gold mud powder according to claim 1, wherein: In step S1 and step S2, the drying temperature is 60-90°C.

8. The method for preparing gold mud powder according to claim 1, wherein: Step S2 also includes adding water to the mixture of flaky gold powder, adhesive and non-ionic surfactant to adjust the gold paste to a viscous state, dipping the viscous gold paste with a brush, allowing the gold paste to naturally drip onto the polyethylene plastic plate under the action of gravity to form small droplets, and then drying.

9. A gold mud powder, characterized in that: The gold mud powder is prepared according to the preparation method of gold mud powder according to any one of claims 1 to 8, and the gold mud powder is used in the fields of gilding Buddha statues, thangkas, sutra writing, and maki-e; when using the gold mud powder, there is no need to polish the object in advance, and the gold mud powder can be directly applied to the smooth surface of the object after adding water to make it viscous.

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