Method for producing glass product

Abstract

To easily, accurately, and cost-effectively form a glass product having a complex internal structure.SOLUTION: A method for producing a glass product includes: forming a wax concave mold by removing an original mold after pouring a wax into the original mold made of a plastic material and curing it; forming a plaster convex mold having the same shape as the original mold by removing the wax concave mold after pouring a plaster into the wax concave mold and curing it; forming a glass concave mold by removing the plaster convex mold after embedding a glass material into the plaster convex mold and curing it.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a method for manufacturing glass products with complex shapes inside glass casting for artworks, sculptures, ornaments, etc., and color baking into the glass interior.

Background Art

[0002] As a typical method used for manufacturing glass products, there is kiln casting. Kiln casting is a technique in which a glass material placed in a mold is fired in an electric furnace, slowly cooled, taken out of the kiln, the mold is removed, and then polished.

[0003] As a method applying this kiln casting, in Patent Document 1, a prototype (such as hands and feet) is pressed against an algin impression material to obtain an intaglio plate. A mixture of wax and cement in a 1:1 ratio is melted by heat and poured into this intaglio plate. The solidified wax and cement is used as a relief plate. Based on this relief plate, another intaglio plate is made using gypsum for quenching as a material. Further, a glass material is put into this intaglio plate and fired in a furnace. The technique is disclosed.

[0004] Also, in Patent Document 2, hands, feet, etc. of a person or an animal are pressed against a dental impression material made of soft rubber to form a first concave mold. Then, by pouring gypsum into this hardened first concave mold and hardening it, a first convex mold is formed. Next, this hardened first convex mold is pressed against abrasive material to form a second concave mold. Further, a molten glass material is poured into this second concave mold and cooled and hardened. The technique is disclosed.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] Although the techniques of the aforementioned patent documents are all good when directly expressing the desired prototype in glass, they cannot create a design that incorporates a complex motif in glass, such as when looking into a puddle, where the other side seems visible but is not actually visible.

[0007] In Patent Document 1, in order to create another concave mold with gypsum for quenching based on a relief mold hardened with wax and cement, the product only has the same form as the relief mold, and there is no core that would be the part for incorporating the design into the glass, so an internal space cannot be created.

[0008] In Patent Document 2, in order to create a concave mold with abrasive materials based on a hardened gypsum relief mold, the product has the same form as the relief mold, and similarly, there is no core, so an internal space cannot be created.

[0009] Also, in mold-taking with alginate impression materials or dental impression materials made of soft rubber, there are limitations in the taper (draft gradient), and the degree of freedom in the shape of the core structure is small. Furthermore, both alginate impression materials and dental impression materials made of soft rubber cannot be recycled after use, and there are also problems in their disposal when discarded.

[0010] Normally, when making a prototype with an opaque material such as clay, in the resulting transparent glass, even in the form of the "depressions" and "shadows" of the clay, depending on the viewing angle, it can become the form of "bulges" and "highlights", and there is a possibility of expressing complex motifs. However, it is difficult to carve the clay prototype while anticipating this, and there was no simple technique for incorporating complex motifs into glass.

[0011] Therefore, the present invention aims to provide a simple technique for incorporating complex motifs into glass, and also to provide an inexpensive manufacturing technique for engraving a space inside the glass by inverting the unevenness to improve safety in the case of installing glass artworks in public spaces.

Means for Solving the Problems

[0012] To solve the above problems, the manufacturing method of the present invention includes a step of pouring wax into a prototype made of a plastic material, curing it, and then removing the prototype to form a wax concave mold; a step of pouring gypsum into the wax concave mold, curing it, and then removing the wax concave mold to form a gypsum convex mold having the same shape as the prototype; and a glass concave mold forming step of embedding a glass material in the gypsum convex mold, curing it, and then removing the gypsum convex mold to form a glass concave mold. As another method, in the gypsum convex mold forming step, the gypsum convex mold is further colored with a mixture of a pigment and the glass material, and in the glass concave mold forming step, the color of the gypsum concave mold is further transferred to the glass concave mold.

Effects of the Invention

[0013] As a result of the manufacturing method of the present invention having the above-described configuration, the outer shape of the product becomes smooth, so it is excellent in strength, there is no risk of breakage or danger during contact, and an improvement in safety in installation in public spaces is expected.

[0014] In addition, since it is easy to reverse the unevenness of the prototype, the creator can freely create the reversed form of the freely created prototype in glass regardless of age and gender from children to adults, the superiority or inferiority of modeling techniques, and proficiency.

[0015] And in this manufacturing method, disposable silicone rubber molds, zircon sand impression materials, dental impression materials, etc. are not used, and it can be reversed only with plastic materials such as clay and pottery and wax that can be used repeatedly, so a reduction in environmental load is expected.

Brief Description of the Drawings

[0016]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Mode for Carrying Out the Invention

[0017] The manufacturing method of the present invention will be described.

[0018] First, as shown in Figure 1, a prototype 1 is made, which will later become the core and the spatial form inside the glass. The material used to make the prototype 1 is clay. This material may be other than clay as long as it is a plastic material. For example, pottery clay may be used. Creating the prototype 1 with a plastic material such as clay can also accommodate shape changes and has the advantage that the form of the internal space of the glass can be freely formed. Also, clay and pottery clay can be reused and do not impose a burden on the environment.

[0019] Next, as shown in Figure 2, the heated wax 2 is applied or poured onto the clay prototype 1 and cooled and solidified. At this time, care must be taken because if the wax components are formulated to be too soft, there is a risk of damaging the wax mold.

[0020] Next, as shown in Figure 3, the clay prototype 1 is removed from the wax 2 to create a cavity 3, and thus the "concave" form is completed. The removed clay can be reused. By processing the wax at this stage, it is also possible to transition from here to creating the "convex" form, the outer shape of the glass. Or, it is also possible to create the final shape of the glass.

[0021] Next, as shown in Fig. 4, apply plaster. After the plaster hardens, perform dewaxing (lost wax) as shown in Fig. 5. In the space 5 from which the wax has been removed, a plaster core mold 4 that will ultimately form the core will be completed. As long as the clay can be removed and the plaster can be removed from the glass after casting, a plaster core mold 4 that can be encapsulated in the glass in any shape can be created. Note that the wax 2 removed at this time can also be reused.

[0022] If you want to color this plaster core mold 4, use a dedicated pigment to color it at this stage. Details will be described later.

[0023] Cast glass 6 into this mold as shown in Fig. 6. After slow cooling, remove the plaster core mold 4 as shown in Fig. 7 to create a cavity 7, and polish the surface to complete the final glass product.

[0024] Here, the wax 2 poured into the clay prototype 1 will be described. Wax is a fluid that does not damage the inner clay prototype 1 and is suitable as a material that does not damage the delicate plaster mold that will function as a core mold. In the present invention, wax is used in a technique called the lost wax technique. Wax is applied to the concave mold of wax, and after the plaster hardens, the wax is melted and removed by heating to function in creating the plaster core mold 4.

[0025] As a formulation example of wax, a mixture of paraffin wax, micro wax, and rosin (pine resin) is used, and in winter, a formulation further containing beeswax is also used. Melt the rosin with a high melting point in a pot, add paraffin, micro, and beeswax in that order, and mix well. Although rosin is likely to precipitate, the presence of this rosin has the effect that when using wax for making a hand-carved prototype, it has good elongation and is less likely to crack even for thin sheet-like or petal-like thin objects. Also, to harden the wax, a larger amount of paraffin wax is formulated.

[0026] Next, a method for casting glass will be described. There are two methods for casting glass 6 into a gypsum mold 4 that can freely shape the air inside the glass. One is kiln casting, where the mold is filled with glass cullets and cast in an electric furnace, and the other is hot casting, where molten glass is scooped from a crucible with a ladle and poured into a preheated mold.

[0027] The advantages of the hot casting method are that since it is cast directly from the crucible, there are few impurities in the glass, and because the glass is at a high temperature, almost no bubbles enter (depending on the state of the glass in the crucible), the polishing of the water surface that does not touch the mold is unnecessary, and above all, the transparency of the glass itself is beautiful. This is because there are few opportunities for impurities to adhere to the glass surface due to the furnace atmosphere, etc. The disadvantages are: (1) Since it is impossible for one person to make large objects, a team needs to be organized; (2) Although the mold can be installed in an upper-cover type annealing furnace and poured directly, there is a risk that the glass melted by the heat source may accidentally adhere and damage the annealing furnace, so a dedicated annealing furnace (such as a rail type hat kiln) is desirable; (3) The color of the glass becomes single-colored; (4) The gypsum mold may be damaged due to the temperature difference and impact when pouring the glass.

[0028] On the other hand, the advantages of kiln casting are: (1) No large-scale equipment or team organization is required; (2) Since the temperature rise of the mold and the glass is the same, there is less damage to the mold; (3) It is cost-effective; (4) Various colored glasses can be controlled and mixed.

[0029] In kiln casting, glass cullets are used. However, the more complex the shape of the cores, the more easily the delicate gypsum will break. When the glass cullets with a specific gravity of 2.3 - 3.0 are filled into the mold, the gypsum may break under the weight. However, if the particles of the glass material are made finer to reduce this, bubbles are likely to occur.

[0030] The mechanism of bubble generation will be briefly explained here. First, when the temperature inside the furnace rises and the glass passes through the transition point, the glass starts to move. If the temperature rise rate from here is fast, the air in the gaps between the glass grains is trapped and becomes bubbles. On the contrary, if it is slow, each glass grain devitrifies and the transparency is lost.

[0031] Therefore, to reduce this, it is necessary to set the temperature rise rate according to the size of the glass grains, and while softening the glass, let the air escape.

[0032] Next, the coloring method will be explained. When coloring, the baking temperature of enamel painting or raster coloring is 580 °C. If the temperature rises above this, the color will burn off. However, nowadays there are also pigments that can be baked at high temperatures, and enamel materials that can be baked at the working temperature of blown glass, 800 °C to 830 °C, can also be obtained.

[0033] When directly coloring the glass using the method of this time, since the inside of the glass is too complex, there were problems sufficient to abandon enamel painting, such as the brush or spray not reaching the core part, or the glass cracking due to reheating because of too large a difference in the thickness of the glass.

[0034] Therefore, it was decided to color the core 4 of the plaster with high-temperature enamel at the mold stage and then cast the glass 6. With this method, coloring is possible because the brush can reach.

[0035] However, even with high-temperature enamel, at a casting temperature of 870 °C, most of the colors burned off. At casting temperatures below this, it is difficult for the glass to flow into a complex plaster mold without applying pressure. Also, since the powder glass used for parts like part - de - viel has the same softening temperature as the main body glass, even if this powder is painted on the plaster core, it will be washed away as the glass softens. Also, although the underglaze, overglaze, and ceramic painting tools for pottery do not flow on the glass, they penetrated into the plaster and did not bake.

[0036] In many cases when conducting the above-mentioned experiments, small test pieces often succeed. This is because factors such as the expansion and contraction of glass, the amount of heat required for the heating speed with respect to weight, and the temperature difference between the outer shell and the center of the glass, even within the allowable range for small test pieces, will result in significant errors when they become larger. However, all the ceramic topcoats used did not adhere to the glass.

[0037] Regarding the color of the pigment, as a binder, methods such as applying CMC (carboxymethyl cellulose), adding sizing, etc. were tried, but it didn't go well. After firing, without removing the plaster, it seems firmly baked like the relationship between pottery and glaze, but when the plaster is removed, it is found that it has not been transferred.

[0038] Finally, to improve this due to the difference in the coefficient of expansion, adding a small amount of the glass 6 intended to be used for casting to the pigment solved all the problems. As a result, a technique for completely transferring pigments and minerals to glass was established.

[0039] In addition, as materials for realizing this glass transfer, for example, 60% of gofun and 40% of glass base are blended. Gofun is, for example, a blend of 40% Fukushima feldspar and 60% synthetic clay ash.

[0040] Also, as other materials for realizing glass transfer, for example, 65% of ceramic undercoat (dry) and 35% of glass base (passed through #100 sieve) can be blended. The blended material is used after being well ground and mixed in a mortar.

[0041] By simultaneously transferring and firing the pattern during glass casting as described above, the fusion of two - dimensional and three - dimensional can be completed within the glass, thus greatly expanding the scope of production. An example of a colored glass product is shown in Fig. 9 according to the present invention. The purpose of incorporating complex motifs into glass can be simply realized.

Industrial Applicability

[0042] Complex motifs can be easily encapsulated in glass, improving safety in the case of glass art installation in public spaces.

Explanation of symbols

[0043] 1 Clay prototype 2 Wax 3 Cavity 4 Plaster mold 5 Space where wax has been removed 6 Glass 7 Cavity 8 Coloring of the plaster mold

Claims

1. A wax concave mold forming step of pouring wax into a prototype made of a plastic material, curing it, and then removing the prototype to form a wax concave mold; A gypsum convex mold forming step of pouring gypsum into the wax concave mold, curing it, and then removing the wax concave mold to form a gypsum convex mold having the same shape as the prototype; A glass concave mold forming step of embedding a glass material in the gypsum convex mold, curing it, and then removing the gypsum convex mold to form a glass concave mold The manufacturing method of the glass product which has.

2. The glass concave mold forming step is Embedding the glass material by filling the gypsum convex mold with solid glass pieces and melting them at a high temperature, The manufacturing method of the glass product according to Claim 1.

3. The glass concave mold forming step is Embedding the glass material by pouring the pre-melted glass material into the gypsum convex mold, The manufacturing method of the glass product according to Claim 1.

4. The gypsum convex mold forming step further includes Coloring the gypsum convex mold with a mixture of a pigment and the glass material, The glass concave mold forming step further includes The coloring of the gypsum convex mold is transferred to the glass concave mold The manufacturing method of the glass product according to Claims 1 to 3.

Images