Method for coating a glass surface with solid particles and method for manufacturing glass containing color-enhancing components.

Abstract

The present invention provides a method for coating solid particles onto a glass surface and a method for manufacturing glass containing color-enhancing components, which allows for the simple and suitable adhesion of solid particles to the glass surface. [Solution] A coating process is performed in which a base material made of glass is brought into contact with a mixture of coating particles, which are solid particles that can adhere to the base material, and a dispersant, which are solid particles that do not adhere to the base material, thereby adhering the coating particles to the surface of the base material. Metal powder can be used as the coating particles, and glass beads can be used as the dispersant. Furthermore, a process is then performed to incorporate the coating particles into the base material.

Description

Technical Field

[0001] The present invention relates to a method for applying solid particles to the surface of glass and a method for producing glass containing a colorant using the method.

Background Art

[0002] In glass art where glass is used as a material to create practical items, artworks, handicrafts, ornaments, etc., for the purpose of imparting visual effects such as coloring to the glass, metal particles are added to the glass.

[0003] The state of the metal particles incorporated into the glass and the resulting color development vary depending on the type and size of the metal particles added, the material of the glass as the base material, the technique for incorporating the metal particles, etc. To give an example, in a technique called lampwork or burner work where glass is melted and shaped with a burner, a rod-shaped glass (referred to as a gold-mixed rod, etc.) in which gold (Au) particles are kneaded may be used as a material.

[0004] The production of a gold-mixed rod is performed, for example, by the following procedure. First, gold foil is wound around a rod-shaped or tubular glass at room temperature. Next, the glass wrapped with the gold foil is covered with another glass heated to a high temperature with a burner. Further, the glass is deformed (at this time, heating with a burner is performed as necessary), and the gold that was originally in the form of foil is kneaded so as to become fine pieces. If sufficient color cannot be obtained at once, the same operations (attachment and kneading of gold foil) are repeated until sufficient color is obtained. In the gold-mixed rod thus produced, the gold particles are incorporated into the glass in a state where they are colored golden, and for example, it presents an appearance in which a large number of fine golden particles are dispersed in transparent glass.

[0005] A gold-mixed rod is used, for example, as a material for imparting a golden color to a part of a handicraft such as a dragonfly bead when creating the handicraft. Alternatively, the gold-mixed rod itself can be shaped into a glass product in which golden particles are dispersed throughout.

[0006] Foil, which is an article made by forming a thin film of metal, is sometimes given different names depending on its thickness. In the case of gold and silver, the thinnest is called gold foil and silver foil, respectively. In the case of gold, for example, a thickness of about 0.1 to 0.3 μm is called gold foil, and a thickness of about 0.7 to 1.0 μm is called supernatant or clear, and in glass art, supernatant is usually used. However, in this specification, these will be referred to as "foil" without distinguishing them by thickness.

[0007] Examples of documents that demonstrate the general level of technical expertise related to glass art, as described above, include the following Patent Documents 1 and 2. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2005-231043 [Patent Document 2] Japanese Patent Publication No. 2007-22899 [Non-patent literature]

[0009] [Non-Patent Document 1] Toshikatsu Kobayashi, "Preparation and Color of Gold and Silver Nanoparticles," Journal of the Society of Inorganic Materials 11, pp. 371-376 (2004). [Non-Patent Document 2] Teruo Sakaino and Taro Moriya, "A Study on the Color Development Process of Copper Red Glass," Journal of the Ceramic Association 69

[12] , pp. 434-437 (1961) [Non-Patent Document 3] Masashi Kikukawa, Yoshiya Abe, Ayana Nakamura, and Izumi Nakai, "Elucidation of the Coloring Factors and Consideration of Manufacturing Methods for Ancient Egyptian Copper Red Glass," Analytical Chemistry 63 [1], pp. 31-40. [Overview of the project] [Problems that the invention aims to solve]

[0010] Incidentally, the process of incorporating metal particles into glass using the procedure described above requires considerable technical skill. When a thin metal foil is heated directly with a flame, it melts into a liquid state, deforms into a lump due to surface tension, and solidifies in that state as the temperature drops. The metal incorporated into the glass in this lump state does not disperse even when the glass is mixed, and does not break into small pieces. Once the metal has formed a lump, it cannot be returned to its original state, at least with normal glassmaking techniques. It is possible to remove it from the glass, but it is a time-consuming process.

[0011] To prevent the foil from clumping, it is necessary to ensure that the entire foil is in close contact with the glass surface when applying it. However, foil, being a thin metal film, is inherently difficult to handle by hand. In particular, evenly applying foil to rod-shaped glass used in lampworking is a challenging task. While foil can be applied relatively easily to flat glass plates, lampworking uses linear heat sources such as gas burners, making it unsuitable for heating flat materials.

[0012] Therefore, there was a need for technology that could easily attach solids such as metals to the glass surface, or incorporate the attached solids into the glass.

[0013] In view of these circumstances, the present invention aims to provide a method for coating solid particles onto a glass surface and a method for manufacturing glass containing color-enhancing components, which can easily and suitably adhere solid particles to the glass surface. [Means for solving the problem]

[0014] The present invention relates to a method for coating solid particles onto a glass surface, characterized by performing a coating step in which a base material made of glass is brought into contact with a mixture of coating particles, which are solid particles that can adhere to the base material, and a dispersant, which are solid particles that do not adhere to the base material as well as the coating particles, thereby causing the coating particles to adhere to the surface of the base material.

[0015] In the method for applying solid particles to the glass surface of the present invention, prior to the application step, a thinning step of softening and stretching the base material can be performed.

[0016] In the method for applying solid particles to the glass surface of the present invention, the applied particles can be metal powders.

[0017] In the method for applying solid particles to the glass surface of the present invention, the dispersant can be glass beads.

[0018] Further, the present invention relates to a method for producing a glass containing a colorant component, characterized in that after adhering the applied particles to the surface of the base material by the method for applying solid particles to the glass surface described above, a step of incorporating the applied particles into the base material is performed.

Effects of the Invention

[0019] According to the method for applying solid particles to the glass surface and the method for producing a glass containing a colorant component of the present invention, it is possible to achieve an excellent effect of easily and suitably adhering solid particles to the glass surface.

Brief Description of the Drawings

[0020] [Figure 1] FIG. 1 is a perspective view showing an example of instruments and materials used in the implementation of the present invention. [Figure 2] FIG. 3 is a flowchart for explaining an example of the procedure of the method for applying solid particles to the glass surface according to the implementation of the present invention and the method for producing a glass containing a colorant component using the same. [Figure 3] FIG. 3 is a side sectional view schematically showing one step in the implementation of the present invention. [Figure 4] FIG. 4 is a side view schematically showing another step in the implementation of the present invention. [Figure 5] FIG. 5 is a side sectional view schematically showing yet another step in the implementation of the present invention. [Figure 6]Figure 6 is a flowchart illustrating an example of a procedure different from that shown in Figure 2, relating to a method for applying solid particles to a glass surface according to the present invention, and a method for manufacturing glass containing color-enhancing components using the same. [Figure 7] Figure 7 is a flowchart illustrating an example of a conventional method for manufacturing glass containing coloring agents. [Figure 8] Figure 8 is a photograph showing the state in which metal powder or foil as an accent coloring component is attached to the surface of the base material, glass. It shows the state in which gold foil is attached to a glass rod, the state in which gold powder is applied to a glass rod using a sponge, and the state in which gold powder is applied to a glass rod using a solid particle dispersant. [Figure 9] Figure 9 shows photographs illustrating the differences in how coated particles adhere to the base material surface depending on the particle size of the dispersant. Figure 9(A) shows the state when dispersants of different particle sizes are mixed with coated particles. Figure 9(B) shows the state when copper powder is coated onto a glass rod using dispersants of different particle sizes. [Modes for carrying out the invention]

[0021] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0022] Figure 1 is a perspective view showing the materials and equipment used in a method for coating a glass surface with solid particles according to the present invention, and in a method for manufacturing glass containing color-enhancing components using the same. In this specification, "glass containing color-enhancing components" refers to glass that contains particles of metal or the like, or their compounds, oxides, colloids, etc., as color-enhancing components, thereby exhibiting a visual effect such as a specific color. Color-enhancing components refer to components added to the base material, glass, to impart a visual effect (several examples of the types of solid particles added and the resulting color-enhancing effects will be explained later). Furthermore, the forms in which color-enhancing components are contained in glass containing color-enhancing components include, for example, a state in which the color-enhancing components, such as metal particles or metal oxides, are kneaded into or dissolved inside the glass, as well as a state in which the metal or its oxide, which is the color-enhancing component, is attached to the surface of the glass by baking or the like.

[0023] For the method of coating a glass surface with solid particles and manufacturing glass containing coloring components, for example, a heating device 2, a base material 4, coating particles 6, and a dispersant 8 as shown in Figure 1 are used. Of course, other devices, instruments, materials, etc. may be used as needed.

[0024] Heating device 2 is a heat source device for heating glass rods and other materials used in glass art, and is, for example, a gas burner. When performing lampwork using soft glass as the material, a fan-type burner can be used, which supplies a flammable gas such as propane or natural gas, or a fuel such as kerosene, and also blows in air with a fan for combustion. In addition to these, various other heat sources can be used as heating device 2 depending on the properties of the material and the technique. For example, when working with hard glass as the material, an oxygen burner may be used, which supplies oxygen along with a flammable gas for combustion at a high temperature. Depending on the technique, heat sources other than burners may also be used. In short, heating device 2 only needs to be a heat source device that can heat the glass material to a temperature at which it can be processed, and various devices can be used as heating device 2.

[0025] The base material 4 is the glass used for processing, and various types of glass that can be used as the object to be processed can be used as the material for the base material 4. Examples of materials for the base material 4 include lead crystal glass, artisanal soda glass (referring to soda glass with relatively low softening and inflection points), alkali silicate glass, and other soft glass. Alternatively, in addition to soft glass, hard glass such as borosilicate glass (holosilicate glass), which has a relatively high softening temperature, or soda-lime glass (a type of soda glass, but with relatively high softening and inflection points), also known as semi-hard glass, may be used as the base material 4.

[0026] Soft glass is a type of glass with a relatively low softening temperature (fracture point, softening point). It can be softened even with a typical fan burner that burns air with flammable gases such as propane, natural gas, or butane (flame temperature around 1,500°C), making it easy to create intricate and diverse designs. (Note that the distinction between soft glass and hard glass is based on the level of their fracture and softening points, not on Mohs hardness.) Examples of values ​​published by manufacturers include lead crystal glass with a fracture point of 460°C and a melting point of 850°C, alkali silicate glass with a softening point of 550°C and a working point of 720°C, and craft soda glass with a fracture point of 480°C and a melting point of 880°C. Due to these properties, soft glass is most commonly used for creating decorative items using lampworking.

[0027] In contrast, hard glass, which softens at a high temperature, is difficult to process with the flame of a burner used for processing soft glass. However, its property of not softening even when heated to a certain temperature can be utilized in techniques such as fuming, where a vaporized metal is sprayed onto the glass surface to produce color. When using hard glass as the base material 4, it is also possible to combine the addition of solid particles (coated particles 6) using the technique described later with fuming. Borosilicate glass has a high melting point of 1,648°C, and this property is often utilized in heat-resistant cookware, tableware, and scientific and chemical equipment.

[0028] Among soda-lime glass, soda-lime glass, which has a relatively high melting point, is sometimes called semi-hard glass because its softening temperature is higher than that of soft glass but lower than that of hard glass. Soda-lime glass is commonly used as a material for many window panes and glass bottles.

[0029] In addition, various types of glass that can be processed using the coating particles 6 described later can be used as the base material 4. Note that the procedure described later assumes the use of soft glass as the base material 4 for lampworking; however, depending on the type of base material 4, techniques other than lampworking may be used.

[0030] When performing lampwork using a heating device 2, which is a gas burner, the shape of the base material 4 is preferably a rod or tube with a diameter of, for example, 1 mm to 20 mm, more preferably around 10 mm (5 mm to 15 mm), but other dimensions or shapes are also acceptable. The type of glass used as the base material 4, as well as the shape and dimensions of the base material 4, can be appropriately selected depending on the technique used and the type of heating device 2.

[0031] The coated particles 6 are solid particles that are coated onto the surface of the glass base material 4 and are further added as a coloring component or its raw material. Any substance can be used as the coated particles 6 as long as it is a solid particle that can adhere to the surface of the glass base material 4, but examples include fine powders of metals such as gold, silver, platinum, and copper, or alloys containing these as components.

[0032] Whether or not the coated particles 6 can adhere to the surface of the base material 4 depends on various factors, including the type of material that makes up the coated particles 6, the distance in the triboelectric series between the material that makes up the coated particles 6 and the material that makes up the base material 4, the specific gravity, shape, and dimensions of the coated particles 6, and the ratio of the dimensions of the coated particles 6 to the shape of the surface of the base material 4 (grooves, holes, irregularities, etc.).

[0033] The particle size of the coating particles 6 is not particularly limited as long as it is small enough to adhere to the surface of the base material 4. It can be appropriately selected depending on the type of substance used as the coating particles 6, its availability, and the desired finish of the color-enhancing glass. For example, if the coating particles 6 are powders of gold, silver, platinum, copper, etc., using powders with an average particle size of, for example, 0.1 μm to 50 μm, more preferably 0.1 μm to 0.5 μm, will allow the process described later to be carried out without any problems. Metal powders are produced, for example, by crushing metal materials with a stamp mill or by kneading foil. Assuming that the particle size of such produced metal particles is the same as that of foil of the same metal, the particle size of the metal particles is, for example, 0.1 μm to 0.2 μm for gold, 0.15 μm to 0.2 μm for platinum, and 0.3 μm to 0.4 μm for silver.

[0034] There are no particular restrictions on the type of material that constitutes the coating particles 6, as long as it is a solid that can adhere to the surface of the base material 4 in the form of particles. However, when considering applications such as glass crafts, gold is particularly useful, and other suitable materials include silver, platinum, copper, or solid alloys or compounds containing one or more of these metals.

[0035] Examples of gold-containing alloys include 18-karat gold, white gold, and pink gold. In addition, the coating particles 6 can be metal powders such as brass powder, aluminum powder, and tin powder, or powders of their compounds, as well as solid particles such as carbon powder, ceramics, and powders of seashells or stones. However, in addition to aesthetic needs, it is necessary to make the particle size small enough to adhere to the glass base material 4, so metal is considered particularly suitable as the coating particles 6. This is because it is easy to process into fine particles, and metal processed into fine powder is readily available as a product.

[0036] The dispersant 8 is a solid particle used in a process described later, which is mixed with the coated particles 6. For example, the dispersant 8 can be a roughly spherical glass granule (glass beads).

[0037] The properties required of the solid particles used as the dispersant 8 are, firstly, that they do not adhere easily to the base material 4 compared to the coated particles 6 (the ease with which the dispersant 8 adheres to the base material 4 is less than the ease with which the coated particles adhere to the base material 4); secondly, that their hardness is not significantly different from that of the base material 4; thirdly, that their density is not too high compared to that of the base material 4; and fourthly, that their surface shape is smooth.

[0038] The ease with which the dispersant 8 adheres to the base material 4 is determined by various factors, including the type of substance that makes up the dispersant 8, the distance on the triboelectric series between the substance that makes up the dispersant 8 and the substance that makes up the base material 4, the specific gravity, shape, and dimensions of the dispersant 8, and the ratio of the dimensions of the dispersant 8 to the surface shape of the base material 4 (grooves, holes, irregularities, etc.). If the ease with which solid particles formed from a certain substance into a predetermined shape and dimensions adhere to the base material 4 is less than the ease with which coated particles 6 formed from another substance into a predetermined shape and dimensions adhere to the base material 4, then the solid particles can be used as the dispersant 8.

[0039] If the hardness of the dispersant 8 significantly exceeds that of the base material 4, the dispersant 8 may scratch the surface of the base material 4 in the process described later. If there are scratches on the surface of the base material 4, when the base material 4 is heated, the molten material may trap air inside the scratches, creating tiny bubbles. Light may reflect and refract through these bubbles, causing turbidity. However, since this turbidity can sometimes be used for aesthetic purposes, scratches and bubbles are not necessarily undesirable. If scratches, bubbles, and turbidity are acceptable, a substance with a hardness significantly exceeding that of the base material 4 may be used as the dispersant 8.

[0040] Conversely, if the hardness of the dispersant 8 is significantly lower than that of the base material 4, scratches may occur on the surface of the dispersant 8 due to contact with the base material 4 in the process described later. In this case, if the same process is repeated using the same dispersant 8, the number of scratches on the surface of the dispersant 8 will increase, and the number of coated particles 6 trapped in those scratches will increase. The coated particles 6 trapped in the scratches on the surface of the dispersant 8 will have difficulty adhering to the surface of the base material 4. In addition, the material of the dispersant 8 itself may break down into small pieces or powder due to the scratches, which may adhere to the base material 4 or be incorporated into the base material 4 during subsequent heating or other processing.

[0041] Based on the above, it is preferable to select the substance used as the dispersant 8 based on the guideline that its new Mohs hardness value is within ±3, and more preferably within ±2, of the new Mohs hardness of the base material 4. The Mohs hardness of glass varies depending on the type and composition of the glass, but is generally considered to be around 3 to 6, with values ​​of 6.5 for soda-lime glass and 7 for quartz glass being reported. Lead crystal glass, which is considered to be easily scratched and easy to process among soft glasses, is thought to have a hardness of around 3.

[0042] Regarding the density of the dispersant 8, if it is too high, it becomes difficult to insert the base material 4 (for example, a thin glass rod stretched to about 1 mm to several mm in thickness) in the process described later. On the other hand, if the density is too low, it will easily shatter, making it difficult to handle. The density of typical glass is, for example, 2.5 to 3 g / cm³. 3 Therefore, the dispersion material 8 has an apparent density of, for example, 0.05 g / cm³. 3 More than 5g / cm 3 Approximately the following, more preferably 1.6 g / cm³ 3 More than 2.5g / cm 3 Solid particles with the following densities are considered suitable.

[0043] The surface of the solid particles used as the dispersant 8 should preferably be smooth. For example, if a porous material such as ceramic is used as the dispersant 8, the coated particles 6 will adhere more easily to the dispersant 8 than to the base material 4 which is glass, resulting in a decrease in yield. Also, if there are sharp parts on the surface of the particles that make up the dispersant 8, these parts may come into contact with the base material 4 and cause scratches on the surface of the base material 4.

[0044] Furthermore, considering the climate of the location where it is used as a material for glass crafting (for example, Japan), the fact that the material's physical properties do not change significantly under those conditions is also a desirable condition for storage and handling.

[0045] For example, glass beads satisfy the above conditions and are suitable as the dispersant 8. When, for example, fine metal powder is used as the coating particles 6 to coat a base material 4 with a diameter of about 1 mm to several cm using the procedure described later, glass beads of various particle sizes can be used as the dispersant 8.

[0046] Glass beads are sold in various particle sizes depending on their intended use. For example, glass beads with average particle sizes ranging from approximately 20 μm or less to 500-700 μm are sold as cutting materials for sandblasting. Alternatively, glass beads with an average particle size of several millimeters are sold for use as substrate in aquariums, for example.

[0047] In the procedure described later, when inserting the base material 4 between the dispersants 8, it is problematic if the dispersants 8 are too large, but glass beads of the dimensions listed above can all be used. However, when considering applying the coating particles 6 thinly and uniformly to the surface of the base material 4, it is desirable for the particle size of the dispersants 8 to be somewhat small. That said, it is not always necessary to pursue thinness and uniformity in the layer of coating particles 6 on the surface of the base material 4, and the preferred particle size of the dispersants 8 will differ depending on what kind of color-enhancing glass you ultimately want to obtain. For example, when you want to make a regular gold polishing rod, it is often not necessary to use dispersants 8 with extremely small particle sizes.

[0048] Furthermore, if the particle size of the dispersant 8 is too small, another problem arises: moisture can cause not only the coated particles 6 but also the dispersant 8 to adhere to the base material 4. Moisture from the atmosphere can adhere to the surface of the glass base material 4, and this, through the action of intermolecular forces and surface tension, causes the dispersant 8 to adhere to the surface of the base material 4. This does not occur if the air is sufficiently dry, but it is a phenomenon that is likely to occur in Japan's humid climate.

[0049] The adhesion of the dispersant 8 to the base material 4 due to moisture is more likely to occur the smaller the particle size of the dispersant 8. This is because the surface area on which the force due to moisture acts becomes larger relative to the mass of the dispersant 8. Specifically, for example, if the dispersant 8 is solid glass beads, adhesion of the dispersant 8 due to moisture is less likely to occur if the particle size is 300 μm or larger, more preferably 500 μm or larger. Alternatively, even if adhesion occurs, the dispersant 8 can be easily removed.

[0050] Based on the inventor's experience, if the particle size of the dispersant 8 is approximately 300 μm or larger, even if moisture is present on the surface of the base material 4 and the dispersant 8 adheres to it, the dispersant 8 can be easily removed by lightly tapping the base material 4 with a hand or by applying an impact such as hitting it against a workbench. For example, if a dispersant 8 with a particle size of approximately 200 μm is used while the surface of the base material 4 is moist, a large amount of the dispersant 8 will adhere strongly to the surface of the base material 4 and will not easily come off even if the base material 4 is subjected to an impact.

[0051] Furthermore, for the reasons mentioned above, it is desirable that the dispersant 8 has a smooth surface. Glass beads that are commonly sold, in which each particle has a smooth, approximately spherical shape, typically have an average particle size of 10 μm to 20 μm at their smallest.

[0052] Based on the above, when using glass beads as the dispersant 8, the average particle size is preferably 10 μm to 1 mm, more preferably 300 μm to 710 μm, and particularly preferably 500 μm to 710 μm, considering the difficulty of adhesion to the base material 4 due to humidity. When used in general lampworking, glass beads of about 30 μm to 710 μm are readily available and can be handled suitably. The numerical ranges shown here are examples considering the availability of glass beads of different particle sizes in a humid climate, and the suitable particle size of the dispersant 8 may vary depending on the environment in which the procedure described later is carried out and the type of glass containing the coloring component to be produced. For example, if it is desired to form a particularly thin layer of coated particles 6 on the surface of the base material 4, a dispersant 8 with a small average particle size can be suitably used if the procedure is carried out in a sufficiently dry environment.

[0053] While soda glass is commonly used as the material for glass beads, other types of glass may also be used. In addition, suitable granular items such as resin beads or small balls of light metal can be used as the dispersant 8.

[0054] In addition, a container 10 is used. The container 10 can be any container that can hold an appropriate amount of dispersant 8 together with the coated particles 6 and has an opening into which the base material 4 can be inserted. For example, a deep dish-shaped or cylindrical container made from resin, ceramics, glass, metal, etc., can be used.

[0055] Next, a method for applying solid particles to a glass surface using the materials and equipment described above, and a method for manufacturing glass containing color-enhancing components using this method will be explained. Figure 2 is a flowchart illustrating an example of the procedure in the method for applying solid particles to a glass surface and the method for manufacturing glass containing color-enhancing components using this method, according to the present invention.

[0056] First, the dispersant 8 and coating particles 6 are placed in container 10 and mixed (mixing step; step S10). The dispersant 8, which is glass beads, and the coating particles 6, which is fine metal powder, are placed in the same container 10 in an appropriate ratio. The ratio of the two is such that, for example, the apparent volume is 10 cm³. 3 For a given amount of dispersant 8, it is preferable to use a coating particle 6 of approximately 0.1 g to 5 g. For example, if the dispersant 8 is glass beads and the coating particle 6 is gold powder, the apparent volume is 10 cm³. 3 Approximately 0.5 g of coating particles 6 are mixed with a certain amount of dispersant 8. If the coating particles 6 are silver powder and silver discoloration is to be performed as described later, the mixing ratio of coating particles 6 to dispersant 8 should be about half that of when the coating particles 6 are gold powder. When the two are mixed, as shown in Figure 3, the coating particles 6 adhere to the surface of the dispersant 8, and the coating particles 6 are dispersed in the gaps between the dispersant 8 particles.

[0057] Note that the ratio of the dispersant 8 to the coating particles 6 mixed here does not need to be precisely measured; an estimate is acceptable. However, these ratios affect the finish and ease of production of the color-enhancing glass. If there are too many coating particles 6 relative to the dispersant 8, the coating particles 6 tend to adhere thickly to the base material 4, while too few tend to result in unevenness. If the coating particles 6 adhere thickly, the finish will be similar to that of using thick foil. If there are too few coating particles 6, the amount can be adjusted by repeatedly kneading and baking. Alternatively, the ratio can be adjusted through trial and error by repeating the procedure described below (steps S10 to S50).

[0058] Note that Figure 3 is a simplified schematic diagram illustrating each element for the purpose of explaining the process, and the shapes and dimensional ratios of the coating particles 6 and dispersant 8 are not accurate. The same applies to Figure 5.

[0059] A portion (or all) of the base material 4 is heated with a heating device 2, which is a burner, to raise the temperature to the point where the glass material of the base material 4 softens, and the softened portion is stretched into a thin shape as shown in Figure 4 (thinning process; step S20).

[0060] When performing the entire process as lampwork, a rod-shaped piece of glass is used as the base material 4. Its tip is heated, grasped with tweezers, and stretched. For example, a portion of the base material 4, which is a rod of glass, weighing about 1g near the tip (to give a specific numerical range, for example, a portion weighing between 0.2g and 5g; in terms of length, for a glass rod with a diameter of about 8mm, the portion at the tip of about 1cm to 2cm) is stretched to a length of several tens of centimeters (for example, between 10cm and 80cm). The diameter of the stretched portion of the base material 4 becomes thin to about 1mm (for example, between 0.1mm and 5mm). Glass rods stretched in this way are sometimes called thin strips or thinly stretched rods.

[0061] For example, if the base material 4 is soft glass, it will soften when heated to around 470°C. In the case of hard glass, it needs to be heated to, for example, around 800°C.

[0062] At the point when the base material 4 is stretched during the miniaturization process, at least the stretched portion of the base material 4 (for convenience, referred to as the miniaturized portion 4a) is heated. Once the miniaturized portion 4a has cooled to room temperature or to a temperature at which it loses its flexibility, the base material 4 is inserted into the mixture of coating particles 6 and dispersant 8, as shown in Figure 5 (coating process; step S30). The coating particles 6 that were adhering to the surface of the dispersant 8 or dispersed between the dispersant 8 adhere thinly and uniformly to the surface of the miniaturized portion 4a of the base material 4 that has been inserted into the dispersant 8. Here, when applying the coating particles 6 to the base material 4, it is not necessarily required to insert the base material 4 into the mixture; it is sufficient for at least a part of the base material 4 to be in contact with the mixture. For example, the coating particles 6 can be applied to the surface of the base material 4 by simply placing the base material 4 on the surface of the mixture or by rolling the base material 4 on the surface of the mixture.

[0063] Here, the adhesion of the coated particles 6 to the surface of the base material 4 does not require glue or adhesive and can be performed at room temperature. The surface of the base material 4, which is glass, appears smooth macroscopically, but microscopically it has fine irregularities, and it is thought that the coated particles 6, which are fine metal powders, get caught in these irregularities and adhere to the surface of the base material 4. Here, a glass with a large microscopic surface area can be said to be lead crystal glass, a type of soft glass. It should be noted that the adhesion of the coated particles 6 to the base material 4 may also be due to other principles.

[0064] When inserting the base material 4 into the mixture of coating particles 6 and dispersant 8, it is not impossible to do so while the base material 4 is still hot and softened. However, there is a possibility that the base material 4 may unexpectedly deform during insertion. Therefore, when applying the base material 4 by inserting it into the mixture, it is better to perform this application process after the base material 4 has cooled and hardened.

[0065] If the amount of coating particles 6 adhering to the surface of the base material 4 is insufficient, the base material 4 (fine-grained portion 4a) may be brought into contact with the mixture of coating particles 6 and dispersant 8 again (step S30 may be performed again), or in that case, the proportion of coating particles 6 in the mixture may be increased (step S10 may be performed again) before step S30 is performed again.

[0066] Through the above steps, the coating particles 6 are attached to the surface of the base material 4, completing the procedure for applying solid particles to the glass surface. Next, a process is performed to incorporate the coating particles 6 into the base material 4. Here, a baking process and a mixing process are described as examples of such processes.

[0067] When the finely milled portion 4a of the base material 4 to which the coated particles 6 are attached is heated again with the heating device 2, the coated particles 6 attached to the surface melt and are baked onto the base material 4 (baking process; step S40). Baking is a process in which, when glass is heated with metal or the like attached to its surface, the glass softens as the temperature rises, and the metal or the like is fixed to the surface of the glass. In the inventor's experience, even when a fan burner is used as the heating device 2, the coated particles 6 are rarely blown off the surface of the base material 4 during heating. Some may be blown off, but this is not a problem, at least when creating glass containing coloring components as a material rod.

[0068] In this way, a glass containing a color-enhancing component is obtained, in which a metal as a color-enhancing component is baked onto the surface of the glass. This can be used as a finished product as a material rod, but depending on the application, the obtained glass containing a color-enhancing component may be further mixed (mixing step; step S50). Since the mixing is performed while the base material 4, which is glass, is flexible, the base material 4 is heated in the heating device 2 as needed. Furthermore, steps S20 to S50 are repeated as needed to incorporate more coated particles 6 into the base material 4. In this way, the layer of coated particles 6 formed on the surface of the base material 4 via steps S10 to S30 is incorporated into the base material 4 in steps S40 to S50, and glass containing a color-enhancing component can be easily manufactured.

[0069] If the coating particles 6 are incorporated into the base material 4 by the mixing process (step S50), the baking process (step S40) can be omitted. The actual procedure, including whether or not to include the baking process, should be selected according to the desired finish.

[0070] Furthermore, it is also possible to manufacture glass containing coloring components using a procedure such as that shown in Figure 6. In the procedure shown in Figure 6, after the coating step (step S30), a coating step (step S60) is performed instead of the baking step (step S40; see Figure 2) to incorporate the coated particles 6 into the base material 4.

[0071] In the coating process, the surface of the base material 4 coated with coating particles 6 is coated with another base material, which is glass. The glass used for coating is heated and softened in a heating device 2, and then wrapped around the base material 4 coated with coating particles 6. Subsequently, these are kneaded together as a single unit (kneading process; step S50) to obtain glass containing coloring components. In this procedure as well, steps S20 to S50 may be repeated as needed, and in some cases, baking may be performed before the coating process (step S60).

[0072] As described above, coating particles 6 are applied to the surface of a glass base material 4, and a color-enhancing component-containing glass can be obtained, which further includes the coating particles 6 as a color-enhancing component. In the series of steps shown in Figures 2 to 5 and Figure 6, it is important that the base material 4 comes into contact with the mixture of coating particles 6 and dispersant 8 when performing the coating step S30. In this mixture, the coating particles 6 are dispersed on the surface of the dispersant 8 and between the dispersant 8 particles, which allows for the application of a moderate amount of coating particles 6 to the surface of the base material 4.

[0073] If the base material 4 is inserted into an aggregate of solid particles consisting only of coated particles 6 without using the dispersant 8, the coated particles 6 will adhere to the surface of the base material 4 in a thick and unevenly distributed manner. If the layer of coated particles 6 attached to the surface of the base material 4 is not uniform, clumps may form in the coated particles 6 when heated in the subsequent baking process (step S40) or mixing process (step S50). In order to uniformly coat the coated particles 6 on the surface of the base material 4, it is necessary to coat the layer of coated particles 6 as thinly as possible. However, if the base material 4 is simply inserted into an aggregate of coated particles 6, the layer of coated particles 6 attached to its surface will be thick. If the mixture consists of coated particles 6 dispersed between the dispersants 8, the base material 4 can be brought into contact with this mixture, such as by inserting it, to thinly coat the surface with coated particles 6. This is a very simple and suitable operation for applying coated particles 6 as a coloring component to the surface of the glass base material 4.

[0074] While other methods exist for thinly adhering the coating particles 6 to the glass, such as applying them with a brush or sponge, such methods result in significant losses due to the scattering of the coating particles 6. Since the coating particles 6 are made of expensive materials such as gold or platinum, it is necessary to minimize losses as much as possible.

[0075] Figure 7 is a flowchart showing an example of a conventional method for manufacturing glass containing coloring components. In the conventional method, for example, when manufacturing a gold-filled rod by adding gold to glass, gold leaf is used as the coloring component. This gold leaf is first attached to the surface of the glass, which serves as the base material (attachment step; step S110). At this time, a glass rod with a diameter of several millimeters is used as the base material. First, the gold leaf is spread on a flat surface, and the glass rod is rolled over it to wrap the gold leaf around its surface.

[0076] This process is sometimes carried out at high temperatures. In this case, the foil is spread on a flat plate, and heated, softened glass is pressed onto it to adhere the foil to the surface. This method has the advantage that the foil can be picked up without waste due to the adhesive force of the softened glass surface, but the temperature drops when the glass is pressed onto the spread foil, so reheating is required before moving on to the next step, resulting in extra time and energy loss.

[0077] Glass with gold leaf attached is heated, then covered with another softened glass (coating step; step S120), and kneaded (kneading step; step S130) to obtain a gold kneading rod or the like as a glass containing a coloring component. If sufficient color is not obtained in one step, steps S110 to S130 are repeated several times.

[0078] The main problem with these conventional methods is the difficulty in handling the foil. When using the supernatant of gold foil, its thickness is, for example, about 1.0 μm, and handling such an extremely thin material requires considerable skill. Therefore, during the application process (step S110), it is difficult to apply it evenly to the surface of the glass, often resulting in wrinkles, tears, or parts of the foil lifting off the surface of the glass. When heated in such a state, the heat is transferred unevenly, causing lumps to form.

[0079] In the procedure shown in Figures 2 and 6, handling is made significantly easier by using powder (coated particles 6, which are solid particles) instead of foil as an additive coloring component. Furthermore, by mixing the coated particles 6 with a dispersant 8, the coated particles 6 are appropriately dispersed, and a thin, uniform layer can be formed on the surface of the base material 4.

[0080] Furthermore, using powder instead of foil in this way offers the advantage of being able to suitably apply the coloring component to items with complex shapes. Even with glass that is difficult to apply foil to uniformly, powder can be easily and evenly applied. For example, one possible method is to form a layer of coating particles 6 on the surface by inserting or dipping a glass that has been formed into a certain shape into a mixture of coating particles 6 and a dispersant 8, and then baking it to obtain a glass product of a certain shape with the coloring component added to the surface. Of course, in this case, the dispersant 8 disperses the coating particles 6, so a thin and uniform layer of coating particles 6 can be formed on the surface of the glass.

[0081] Furthermore, in the conventional method shown in Figure 7, where foil is used as a coloring component and then incorporated into the glass through coating and mixing, a certain amount of both the base material (glass) and the coloring component (foil) is required to obtain a rich color. This is because both the foil and the glass need a certain surface area to uniformly adhere a thin foil to the surface of the glass. To secure the surface area for adhesion, a corresponding volume of glass is required, and to obtain sufficient color in the glass, an amount of coloring component proportional to the volume of glass is required. Coloring components are often expensive materials such as gold foil, but in the conventional method shown in Figure 7, it is difficult to use only a small amount of such expensive materials to produce glass containing a small amount of coloring component.

[0082] As shown in the procedures in Figures 2 and 6, when powder is used as the coloring component, the process of attaching the coloring component, which takes the form of a foil-like surface, to the surface of the glass is unnecessary, and the coloring component can be easily applied to the base material 4 with a small surface area. Therefore, the coloring component can be suitably and easily applied to glass that has been thinned by a thinning process (step S20), for example. It is easy to manufacture glass containing a small amount of coloring component by using a small amount of coloring component (such as gold powder) and incorporating it into a small amount of glass.

[0083] Furthermore, considering the case where a color-enhancing component is applied to the surface of a base material 4 that has been thinly rolled to a diameter of about 1 mm, and the case where a color-enhancing component is applied to the surface of a base material with a diameter of about 1 cm, the ratio of the surface area on which the color-enhancing component is applied to the volume of the base material will differ, and the amount of coating particles 6 added to the base material may be greater in the former case. Therefore, when trying to create glass containing color-enhancing components of the same intensity, for example, if using a technique that involves applying foil, several to several tens of times kneading is required. However, with the procedure shown in Figure 2, depending on the amount of material used, it is possible to create glass containing color-enhancing components of sufficient intensity with fewer applications and kneading steps.

[0084] In the conventional method shown in Figure 7, the steps of spreading the foil and attaching it to the glass (attachment step; step S110) are time-consuming and laborious each time. Furthermore, in order to obtain sufficient color development, it is necessary to repeat the procedure many times, adding a coating step (step S120) and a mixing step (step S130). However, in the method shown in Figures 2 and 6, the procedure of applying the coloring component (coating particles 6) to the surface of the base material 4 is simple and time-saving, and the number of times steps S20 to S50 are performed is also reduced.

[0085] In the foil application technique, it is necessary to carefully and slowly handle the thin metal foil with both hands. However, with the method using coating particles 6 and dispersant 8, it is simply a matter of dipping the glass held in one hand into the mixture. Furthermore, if the thinning process (step S20) is performed before the coating process (step S30), as mentioned above, it is necessary to wait until the glass temperature has decreased to a certain extent. However, since the glass is drawn into thin strips, it dissipates heat quickly and quickly cools down to a temperature that can be touched by hand, allowing for a quick transition to the subsequent step S30. Thus, the procedures shown in Figures 2 and 6 allow for the creation of color-containing glass with significantly less effort and time compared to the procedure shown in Figure 7.

[0086] Figure 8 shows photographs comparing the state of glass after the bonding process (step S110) in the conventional procedure (see Figure 7) and the state of glass after the coating process (step S20) in the procedure of this embodiment (see Figures 2 and 6). In Figure 8, the top image shows glass with gold leaf attached to the surface, and the bottom image shows glass with gold powder coated on the surface using glass beads as a dispersant. In the center, a reference example of glass with gold powder coated on the surface using a sponge instead of a dispersant is shown. As the glass (base material), a cylindrical black glass with a diameter of 2 mm is used. The end of a ruler with markings at 1 mm intervals is shown on the right side of the screen.

[0087] Applying thin gold leaf to rod-shaped glass, especially thin rods with a diameter of around 1 mm to several mm, requires delicate handling, and it is extremely difficult to apply it uniformly without gaps to the glass surface. In the example shown at the top of Figure 8, wrinkles and tears can be seen throughout. When mixing this to create gold polishing rods, some wrinkles and tears do not pose a major problem, but if there are areas where the foil is significantly raised from the glass surface, lumps are more likely to form when heated.

[0088] On the other hand, in the example where gold powder is applied using a diffuser according to the procedure described above (see the bottom of Figure 8), the gold powder forms a uniform layer on the glass surface. Because the metal adheres to the glass surface in the form of powder rather than foil, wrinkles and lifting do not occur. If firing or mixing is performed in this state, the gold powder as a coloring component will be incorporated into the glass in a suitable manner.

[0089] When using gold powder as a coloring agent, it can be applied to the glass using a sponge or brush. In the example shown in the center of Figure 8, gold powder is taken onto the surface of a sponge used for cosmetics, etc., and then applied to the surface of the glass. Although this method also allows for uniform application of gold powder to the glass surface, a large amount of gold powder adheres to the sponge, resulting in a small amount applied to the glass. Therefore, in order to obtain an appropriate concentration, it may be necessary to repeat the application and baking or mixing process several times, and this method has the disadvantage of having a poor yield of gold powder as a material.

[0090] As described above, the method of applying coating particles 6 to glass (base material 4) is simple and preferable, as shown in Figures 2 and 6, by using a dispersant 8 which is a solid particle.

[0091] Furthermore, we will examine the particle size (size) of the solid particles used as the dispersant 8. Figure 9 is a photograph showing the difference in how the coated particles 6 adhere to the surface of the base material depending on the particle size of the dispersant 8. Figure 9(A) shows the state in which dispersants 8 with different particle sizes are mixed with the coated particles 6, and Figure 9(B) shows the state in which copper powder is applied to the base material 4 (glass rod) using dispersants 8 with different particle sizes.

[0092] Figure 9(A) shows, from left to right, copper powder only, a mixture of copper powder and sandblasting glass beads with a central particle size of 38 μm to 53 μm, a mixture of copper powder and sandblasting glass beads with a central particle size of 500 μm to 710 μm, and a mixture of copper powder and aquarium glass beads with a central particle size of 3 mm to 8 mm. The three images on the right show how the copper powder (coated particles 6) adheres uniformly to the surface of the glass beads (dispersant 8) with different particle sizes.

[0093] The photographs in Figure 9(B) show the state in which the coated particles 6, or a mixture of the coated particles 6 and the dispersant 8, are applied to the surface of a glass rod (base material 4). From left to right, the images show the following: a glass rod inserted into copper powder only; a glass rod inserted into a mixture of sandblasting glass beads with a central particle size of 38 μm to 53 μm and copper powder; a glass rod inserted into a mixture of sandblasting glass beads with a central particle size of 500 μm to 710 μm and copper powder; and a glass rod inserted into a mixture of aquarium glass beads with a central particle size of 3 mm to 8 mm and copper powder. Black glass rods are used.

[0094] In the photograph in Figure 9(B), copper powder-coated glass rods are shown in two rows, upper and lower. The glass rods in corresponding positions in the upper and lower rows are the same; the lighting position when the photographs were taken is different for the upper and lower rows. A ruler with 1mm markings is visible in the background.

[0095] The leftmost glass rod, which does not use dispersant 8, and the three glass rods on the right, which are coated with coating particles 6 using dispersant 8, appear slightly different in their surface gloss. Specifically, the highlights visible on the surface of the three rods on the right (shown with a rectangular frame in the lower section) are not observed on the leftmost rod. These highlights are thought to be reflections of light from the surface of the glass rod visible through a thin layer of copper powder. In other words, in the leftmost rod, which does not use dispersant 8, a thick layer of copper powder adheres to the surface of the glass rod, whereas in the three rods on the right, which use dispersant 8, a thin, uniform layer of copper powder forms on the surface of the glass rod. In this way, if a thin layer of metal coating particles can be attached to the surface of the base material (glass), it is less likely to clump when the metal particles are incorporated into the base material afterward, making it easier to create glass containing colored components with a beautiful finish.

[0096] Glasswork such as lampwork beads incorporates a variety of colorful glass, and such glasswork is created using glass of various colors that have been dyed in different shades. In recent years, lampwork using soft glass, which is relatively easy to start, has become popular, and glass rods (material rods) of various colors are sold as materials for it.

[0097] Beginners in lampworking typically use commercially available glass rods and combine their colors to create their pieces. If the desired color of glass rod isn't available, they'll have to make it themselves, but mixing different colored glass is difficult. Beginner-friendly burners don't have high heat output, making it difficult to raise the glass to a temperature sufficient for easy mixing. For these reasons, especially for beginners, it's generally best to choose from commercially available colors rather than creating the desired glass color themselves.

[0098] Once you become accustomed to this method of creation and the idea that colored glass and material rods are things you buy rather than make, you tend to exclude the option of creating your own materials when making glass art. For example, if you conceive of a glass piece that incorporates gold, and gold-molding rods are not sold, you have no choice but to make them yourself. This requires gathering the necessary glass materials and expensive gold leaf, and then spending time and effort learning everything from how to handle the gold leaf to how to mold the glass. This is a high hurdle for beginners who are used to choosing their desired color from commercially available glass rods. As a result, they end up excluding pieces that use gold from their own creations altogether.

[0099] According to the method for applying solid particles to the glass surface and the method for manufacturing glass containing coloring components described in the above embodiment, handling materials such as gold and silver in glass art becomes significantly easier compared to conventional techniques. Even beginners will be able to easily create gold polishing rods and tarnish silver, which is expected to greatly expand the range of creative possibilities.

[0100] Note that among the procedures shown in Figures 2 and 6, the miniaturization step (step S20) is not mandatory, and the coating process using the coating particles 6 and dispersant 8 can be performed similarly even on glass of a certain thickness and size.

[0101] Furthermore, although this explanation assumes a lampwork using a rod-shaped glass as the base material 4 and a burner as the heating device 2, the method of applying solid particles to the glass surface and the method of manufacturing glass containing coloring components described above can be applied to other techniques as well. For example, in techniques called kilnwork or fusing, which use plate glass as the material and an electric furnace or the like as the heating device, it is considered possible to, for example, apply the coating particles to the surface by bringing the plate glass into contact with a mixture of coating particles and a dispersant, or to heat it to create glass containing coloring components.

[0102] Furthermore, it is theoretically possible (though the available materials would be somewhat limited) to use materials other than glass as the base material and apply or incorporate solid particles in a similar manner. In that case, possible base materials include wood, metal, ceramic, resin, and rubber. However, for many of these materials other than glass, suitable coloring, film formation, and component addition techniques have been established separately. The procedure described above is particularly useful when glass is used as the base material. However, it is possible to incorporate metal into the glass layer of glaze formed on the surface of ceramics or porcelain using a similar method.

[0103] The following summarizes the knowledge gained through empirical rules and scientific analysis regarding the types of materials and color development in the technique of adding colorants to glass. Note that this includes information not directly related to the techniques described above.

[0104] (Regarding gold (Au) and its alloys) In typical lampworking, when gold or its alloys are incorporated into glass, the incorporated gold often develops a golden color within the glass itself.

[0105] Another color produced by gold is a red color known as gold red. This is not achieved by mixing gold leaf or powder into the glass, but by dissolving gold in aqua regia, drying it to obtain a powder containing gold chloride, and then dissolving this powder in weakly acidic glass. At the time of dissolution, it is colorless, but as the temperature decreases, the gold that was dissolved in the glass as chloride precipitates as colloidal particles, resulting in a red color. This coloration is thought to be caused by a phenomenon called surface plasmon resonance, in which the electrons of the gold particles vibrate collectively in response to light (see, for example, Non-Patent Document 1 above). Depending on the size of the gold particles, colors other than red, such as purple, pink, or orange, may also be produced.

[0106] Furthermore, when gold is vapor-deposited (fumed) onto hard glass, it develops a pink to orange color, similar to gold-red. This coloration is likely due to gold colloids.

[0107] Furthermore, if a gold alloy with a high silver content is added to glass through lampworking or other means, discoloration due to silver tarnishing, as described below, may occur.

[0108] (About silver) In the case of silver, various colors can be exhibited through techniques called silver iridescence, silver transformation, etc. (Here, silver transformation refers to the technique or phenomenon of obtaining a discoloration effect using silver in lampwork using soft glass as the material. Note that silver transformation is sometimes called silver kiln transformation, etc., but kiln transformation is a term that refers to the change in color caused by silver during the firing of pottery or cloisonné, and is not an appropriate term to describe the discoloration using silver in glasswork. Also, it is sometimes called soft fume because it produces an effect similar to fuming (deposition of metal onto the glass surface) in hard glass, but the process of silver transformation in soft glass is significantly different from fuming in hard glass).

[0109] The coloration in silver discoloration is thought to be caused by surface plasmon resonance, similar to the gold red coloration described above (see Non-Patent Document 1 above). Silver is first dissolved into glass, and then the temperature is adjusted by the heating method (how the burner flame is applied), thereby adjusting the size of the silver particles that precipitate as colloids from the glass. The coloration due to surface plasmon resonance is determined by the size of the colloidal particles, and in the case of silver, it exhibits colors such as blue, purple, and white.

[0110] Silver discoloration is performed using glass with an ionic charge that allows silver to dissolve, such as lead crystal glass. First, silver is dissolved into the glass. When silver is attached to the surface of the glass in the form of foil or powder and heated, the silver dissolves into the glass and the silver color gradually disappears. Next, by applying ions contained in the flame to the surface with dissolved silver, the silver that was dissolved in the glass as ions precipitates as silver nanoparticles. Furthermore, as the temperature of the glass decreases, the precipitated silver particles grow.

[0111] As mentioned above, the blue and purple colors are thought to be due to plasmon resonance. However, when the precipitated silver particles grow larger than the range in which plasmon resonance causes coloration, the color of silver itself (so-called silver) is produced.

[0112] Furthermore, when silver is deposited (fumed) onto hard glass, the silver adhering to the glass surface is thought to become colloidal fine particles, and the resulting color is thought to be due to surface plasmon resonance, with the color depending on the size of the particles. In addition, when coloring hard glass by fuming, both gold and silver are sometimes used, and layering these can produce colors such as green.

[0113] (About Platinum) Like gold (Au), platinum exhibits metallic platinum coloration within glass. Furthermore, platinum has a higher melting point than gold and silver, making it relatively easier to handle. For example, when incorporating platinum powder into glass, even small amounts of platinum are easier to work with. Also, even when using hard glass as the base material, platinum's melting point is significantly higher than that of hard glass, allowing platinum powder to be easily incorporated into the glass using the methods described above.

[0114] (Regarding copper and other metals) In the case of copper, it often exhibits a blue color within the glass. When fine copper powder is mixed into the glass while oxidizing it, a blue color is obtained, which is thought to be due to the coloration caused by divalent copper ions. Furthermore, when copper is added to glass under reducing conditions, a red color called copper red is produced due to metallic copper colloids or monovalent copper ions (see Non-Patent Documents 2 and 3 above).

[0115] In addition to these, various metals have been used as colorants for glass since ancient times. For example, cobalt oxide is used as a blue colorant, and iron oxide is used as a green colorant. In most cases, these colorants produce color when the metal compounds or metal ions dissolved in the glass absorb light of a specific wavelength. However, some metals (gold, silver, copper, and platinum) exhibit color through different principles, as described above. It is thought that the differences in the principles of color development within glass are largely due to the differences in the ionization tendencies of each metal atom.

[0116] Furthermore, the method for applying solid particles to a glass surface and the method for producing glass containing color-enhancing components according to the present invention are not limited to the examples described above, and various modifications can be made without departing from the scope of the invention. [Explanation of symbols]

[0117] 2: Heating device, 4: Base material, 4a: Fine part, 6: Coating particles, 8: Dispersion material, 10: Container

Claims

1. A base material made of glass, Coating particles are solid particles that can adhere to the base material, By bringing the coated particles into contact with a mixture of solid particles, which are less likely to adhere to the base material than the coated particles, Performing a coating step to adhere the coating particles to the surface of the base material. A method for coating a glass surface with solid particles, characterized by the following.

2. Prior to the coating process, a thinning process is performed to soften and stretch the base material. A method for coating a glass surface with solid particles according to claim 1, characterized in that...

3. The coating particles are metal powder. A method for coating a glass surface with solid particles according to claim 1, characterized in that...

4. The aforementioned dispersant is glass beads. A method for coating a glass surface with solid particles according to claim 1, characterized in that...

5. The method for applying solid particles to a glass surface according to any one of claims 1 to 4 involves first attaching the applied particles to the surface of the base material, and then performing the step of incorporating the applied particles into the base material. A method for manufacturing glass containing color-enhancing components, characterized by the above.

Images