A drastic kiln glaze and a preparation method thereof

Abstract

The present application relates to a kind of severe kiln glaze and its preparation method, including the following weight percentage component raw materials: base glaze raw material: potassium feldspar 15-20%, 5-10% of nepheline, 15-20% of quartz, 20-25% of calcite, 3-5% of dolomite, 2-4% of zinc burning, 12-15% of barium carbonate, 8-12% of boundary card mud, 12.2-19.3% of color agent;Surface glaze raw material: high borosilicon block 15-20%, 10-13% of quartz, 10-15% of calcite, 5-8% of talc, 15-20% of spodumene, 5-7% of zinc burning, 14-20% of potassium feldspar, 7-10% of boundary card mud, 5-8% of titanium dioxide, 2-5% of bismuth oxide, 1-3% of color agent;The present application improves the washing performance of glaze surface, reduces the microstructure defect of glaze surface, improves the stability and the degree of beauty of kiln decoration effect.

Description

Technical Field

[0001] This invention belongs to the field of inorganic non-metallic ceramic glaze technology, specifically relating to a glaze with intense kiln transformation and its preparation method. Background Technology

[0002] The market currently offers a rich variety of stoneware daily-use products, primarily in the form of colored glazes, including ordinary monochrome glazes, kiln-transformed glazes, and crystalline glazes. Among these, kiln-transformed glazes, with their unique natural textures and strong artistic expression, are highly sought after and have become one of the core directions in ceramic decoration technology.

[0003] However, existing kiln-transformed glaze technologies still have certain limitations. Although various kiln-transformed glaze products are available on the market, achieving a dramatic, rich, and stable kiln-transformation effect often comes at the cost of maintaining the physicochemical properties of the glaze, especially the dishwasher resistance essential for everyday ceramics. Traditional kiln-transformed glazes are prone to problems such as decreased gloss, color changes, or surface corrosion after repeated washing, which limits their application in the high-end everyday ceramics sector. Furthermore, existing technologies struggle to maintain an overall blue glaze tone while naturally creating a clear and strong yellow-brown kiln-transformation contrast effect in the relief and edges. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a glaze with intense kiln transformation and its preparation method, which improves the dishwasher cleaning resistance of the glaze, reduces microstructural defects of the glaze, and improves the stability and aesthetics of the kiln transformation decoration effect.

[0005] This invention provides a glaze with intense kiln transformation, comprising the following raw materials by weight percentage: Base glaze raw materials: potassium feldspar 15-20%, nepheline 5-10%, quartz 15-20%, calcite 20-25%, dolomite 3-5%, calcined zinc 2-4%, barium carbonate 12-15%, jiepai clay 8-12%, colorant 12.2-19.3%; Glaze raw materials: 15-20% high borosilicate frit, 10-13% quartz, 10-15% calcite, 5-8% talc, 15-20% spodumene, 5-7% calcined zinc, 14-20% potassium feldspar, 7-10% glaze clay, 5-8% titanium dioxide, 2-5% bismuth oxide, and 1-3% colorant.

[0006] Preferably, the raw materials include the following components by weight percentage: Base glaze raw materials: potassium feldspar 15%, nepheline 7%, quartz 17.7%, calcite 22%, dolomite 3%, calcined zinc 2%, barium carbonate 13%, jiepai clay 8%, colorant 12.3%; Glaze raw materials: 18% high borosilicate frit, 10% quartz, 11% calcite, 5% talc, 18% spodumene, 5% calcined zinc, 14% potassium feldspar, 7% jiepai clay, 6% titanium dioxide, 4% bismuth oxide, and 2% colorant.

[0007] Preferably, the colorant in the base glaze raw material includes iron oxide red, manganese carbonate and cobalt oxide, and the colorant in the top glaze raw material is vanadium blue or cobalt blue.

[0008] Preferably, the base glaze material comprises the following components by weight percentage: 10-15% iron oxide red, 2-4% manganese carbonate, and 0.2-0.3% cobalt oxide (the 10-15% iron oxide red, 2-4% manganese carbonate, and 0.2-0.3% cobalt oxide refer to their weight percentage in the total top glaze material), and the colorant in the top glaze material is cobalt blue.

[0009] This invention provides a method for preparing the intensely kiln-transformed glaze, wherein the base glaze raw material and the top glaze raw material are added to water, wet-milled, sieved, and adjusted to a suitable concentration to obtain a base glaze slurry and a top glaze slurry, respectively; then the base glaze slurry is applied to the body and dried to form a base glaze layer; then the top glaze slurry is evenly applied to the base glaze layer; and the body is fired in an oxidizing atmosphere at a maximum firing temperature of 1180-1210℃ to obtain the intensely kiln-transformed glaze.

[0010] Preferably, in wet ball milling, the mass ratio of raw material, ball milling stone, and water is 1:1.5:0.7, and the mixture passes through a 120-mesh sieve.

[0011] Preferably, the concentration of the base glaze slurry is controlled at 35-45 Baume degrees.

[0012] Preferably, the concentration of the surface glaze slurry is controlled at 55-60 Baume degrees.

[0013] Preferably, the base glaze is applied to the body by dipping, and the top glaze is applied to the base glaze by spraying. After the top glaze is evenly applied to the base glaze, it is left to stand for 0.2-0.5 hours.

[0014] Preferably, the maximum firing temperature is 1190℃.

[0015] As an example, the raw materials used in this invention are described below: High borosilicate frit: Produced in Liling, it is the main flux in glaze. It has a strong fluxing effect, high gloss, and can increase the high-temperature fluidity of glaze. However, it has a large coefficient of expansion, so its usage in glaze should be controlled reasonably.

[0016] Potassium feldspar: Produced in Hubei Province, it is used as the main flux in glazes to reduce the melting temperature and viscosity of the glaze. Potassium feldspar has a wide melting temperature range and strong chemical stability, which is beneficial for controlling firing and preventing product deformation.

[0017] Corundum: Produced in Guangdong Province, it is used as the main flux in glazes. It can reduce the melting temperature and viscosity of the glaze, which is beneficial for firing control and preventing product deformation.

[0018] Quartz: Produced in Liling, quartz is the main source of silica in glaze. Adding quartz to glaze can improve the wear resistance, hardness, whiteness, transparency and chemical stability of the glaze surface.

[0019] Calcite: Produced in Guangxi, its main component is calcium carbonate. During firing, it decomposes into calcium oxide, which can lower the melting temperature of the glaze, reduce the high-temperature viscosity of the glaze, promote the production of the intermediate layer between the body and the glaze, increase the elasticity of the glaze, prevent glaze cracking, and prevent glaze peeling and glaze piling. The main reaction mechanism of the double-layer flow differential reaction glaze of this invention is the flow of the glaze layer. Calcite plays a significant role in increasing the fluidity of the glaze layer. However, theoretically, the amount of calcite in the glaze should not exceed 18%, otherwise it is easy to cause cold cracking of the glaze surface.

[0020] Wollastonite: Produced in Shanggao, Jiangxi Province, its main components are silicon dioxide and calcium oxide. It can reduce the fluidity and elasticity of glaze. In this invention, wollastonite is added as a supplement to calcium oxide when the amount of calcite is close to the critical point, which further increases the fluidity of the glaze layer.

[0021] Spodumene: Originating in Australia, its main component is lithium oxide. It is a strong flux that can lower the melting temperature and high-temperature viscosity of glazes, and improve the gloss and mechanical strength of porcelain.

[0022] Talc: Produced in Guangxi, its main component is magnesium oxide. It can reduce the melting temperature and expansion coefficient of glazes and improve their elasticity.

[0023] Dolomite: Dolomite is a double salt of calcium carbonate and magnesium carbonate, mainly used as a fluxing agent in glazes to improve the gloss and transparency of the glaze surface.

[0024] Zinc oxide: Produced in Zhuzhou area, it is industrial zinc oxide. In glaze, it can act as a flux, reduce expansion, prevent cracking, increase gloss and whiteness, have a positive effect on elasticity, and increase the maturation temperature range.

[0025] Barium carbonate: Produced in Hebei Province, it can become a stronger flux than other alkaline earth metals under certain conditions, and improve the gloss and hardness of glazes.

[0026] Titanium dioxide: produced in Panzhihua, its main component is titanium oxide, and it is a type of opacifier used in glazes. In this invention, it mainly precipitates rutile, showing a white-yellow crystalline effect.

[0027] Jiepai clay: produced in Liling, it incorporates substances such as silica and alumina to give the glaze slurry suspension and stability, and to increase the melting temperature of the glaze.

[0028] Bismuth oxide: Produced in Taishan City, it is a yellow powder that is insoluble in water. At high temperatures, it can significantly reduce the melting temperature of glazes and improve their high-temperature fluidity.

[0029] The beneficial effects of this invention are that the bright blue kiln-transformation glaze of this invention has a soft luster and a strong and consistent reaction effect. It can naturally reflect a clear yellow-brown kiln-transformation effect in any relief and edge, forming a strong contrast with the main blue kiln-transformation color of the whole body, resulting in a very rich overall effect.

[0030] This invention relates to a bright blue kiln-transformed glaze. The brilliant blue color is achieved by adding iron, manganese, and cobalt to the base glaze, while a large amount of low-temperature flux and titanium are introduced into the top glaze. During firing, the top glaze melts before the base glaze. Even when the top glaze is completely melted, the base glaze continues to release colorants into it, resulting in a vibrant color. When both glazes are fully melted, both the base and top glazes exhibit good fluidity, with the top glaze being particularly fluid. This fluidity causes the darker areas of the base glaze to flow to lower areas, creating a clear yellowish-brown hue in the relief and at the edges. Simultaneously, this strong fluidity pulls the white titanium crystals into twisted, filamentous kiln-transformations. As the temperature changes, the glaze rapidly enters the cooling stage, solidifying and preserving the reaction effect. Upon firing, the resulting bright blue kiln-transformed glaze exhibits the effect of this invention.

[0031] This invention primarily utilizes the iron, manganese, and cobalt in the base glaze to achieve color development. Simultaneously, the color flows along with the titanium crystals in the top glaze, thus achieving a dramatic, stringy kiln-transformation effect. Furthermore, the base glaze has a higher initial melting point than the top glaze, and the strong fluidity of the top glaze naturally causes the base glaze color to appear lighter at higher areas, creating a richer kiln-transformation effect with varying color differences.

[0032] This invention utilizes a two-layer glaze formulation differentiation to achieve a unique glaze technology that, under kiln conditions between 1170℃ and 1230℃, and a 7-hour curved firing process, results in a base glaze oxide undergoing a violent reaction that erodes the top glaze, flowing synchronously with it. Furthermore, the titanium crystals in the top glaze crystallize and flow with the molten state, ultimately achieving a stable blue color and a unique kiln-transformed texture from the titanium crystals.

[0033] This invention presents a glossy blue kiln-transformation glaze with a surface reaction effect distinct from existing reactive glazes on the market, making it a highly innovative and marketable reactive glaze. Its glaze surface exhibits a soft luster, with a vigorous and consistent reactive effect. Clear yellow-brown kiln-transformation effects naturally appear on any relief and edges, creating a strong contrast with the overall blue kiln-transformation main color, resulting in a very rich overall effect. This glossy blue kiln-transformation glaze primarily utilizes iron, manganese, and cobalt in the base glaze for color development. Simultaneously, the color flows along with titanium crystals in the top glaze, achieving a dramatic, stringy kiln-transformation effect. Furthermore, the base glaze has a higher initial melting point than the top glaze, and the strong fluidity of the top glaze naturally causes the base glaze color to appear lighter at higher areas, creating a richer kiln-transformation effect with varying color differences.

[0034] The base glaze of this invention uses a high-calcium, high-barium glass glaze, while the top glaze incorporates bismuth oxide and a high lithium content. During firing, the bismuth oxide significantly lowers the glaze's melting temperature and enhances its high-temperature fluidity. Combined with lithium and barium, it forms a liquid-phase separation, resulting in vigorous flow and color fusion at high temperatures, creating a blue and white interlaced pattern. Furthermore, the glaze surface maintains a complete structure and exhibits strong corrosion resistance. The rational proportions of the raw materials in this invention not only preserve the strong kiln transformation effect brought about by the powerful flux but also achieve high dishwasher performance for everyday ceramics due to the complete, highly smooth, alkali-resistant glaze surface. It can withstand 200 dishwasher tests without any change in appearance. Attached Figure Description

[0035] Figure 1 These are images of the ceramic product of Embodiment 1 of the present invention before and after testing.

[0036] Figure 2 Images of the ceramic product of Comparative Example 1 of this invention before and after testing.

[0037] Figure 3 Images of the ceramic product of Comparative Example 2 of this invention before and after testing.

[0038] Figure 4 Images of the ceramic product of Comparative Example 3 of this invention before and after testing. Detailed Implementation

[0039] Example 1 A method for preparing a glaze with dramatic kiln transformation includes the following steps: 1. Prepare base glaze and top glaze materials The base glaze raw materials, calculated by weight percentage, are: potassium feldspar 15%, nepheline 7%, quartz 17.7%, calcite 22%, dolomite 3%, calcined zinc 2%, barium carbonate 13%, jiepai clay 8%, iron oxide red 10%, manganese carbonate 2%, and cobalt oxide 0.3%. The raw materials for the glaze, calculated by weight percentage, are: 18% high borosilicate frit, 10% quartz, 11% calcite, 5% talc, 18% spodumene, 5% calcined zinc, 14% potassium feldspar, 7% jiepai clay, 6% titanium dioxide, 4% bismuth oxide, and 2% cobalt blue.

[0040] The chemical composition of the high borosilicate frit is shown in the table below.

[0041]

[0042] 2. Add the base glaze raw material and the top glaze raw material to a ball mill separately, and add water to each separately according to the ratio, and ball mill them independently to make slurry. The mass ratio of raw material, ball mill, and water is 1:1.5:0.7. Use high-alumina ball mills of different sizes for grinding, where the mass ratio of large, medium, and small ball mills is 2:5.5:2.5. The ball milling time for the base glaze raw material is 15 hours, and the ball milling time for the top glaze raw material is 20 hours. After the glaze is discharged from the ball mill, it is passed through a 120-mesh sieve to obtain the glaze slurry.

[0043] 3. Adjust the concentration of the base glaze slurry to 40 Baume degrees by adding water, and adjust the concentration of the top glaze slurry to 58 Baume degrees by adding water. Apply the base glaze slurry to the surface of the body using the immersion method and dry it at 80°C for 1 hour. After drying, a base glaze layer is formed. Apply the top glaze slurry evenly to the base glaze layer using the spray method to form a top glaze layer. After standing at room temperature for 0.3 hours, send the resulting glazed body into a roller kiln for oxidizing atmosphere firing. The firing cycle is 7 hours, and the maximum firing temperature is 1190°C.

[0044] 4. After firing, the ceramic product is cooled to room temperature in the furnace.

[0045] Comparative Example 1 Compared with Example 1, Comparative Example 1 differs in that the base glaze material and the top glaze material are different, while the rest are the same as Example 1.

[0046] The base glaze raw materials, calculated by weight percentage, are: potassium feldspar 12%, nepheline 10%, quartz 22%, calcite 20%, dolomite 3%, calcined zinc 2%, barium carbonate 12%, jiepai clay 8.7%, iron oxide red 10%, and cobalt oxide 0.3%. The raw materials for the glaze, calculated by weight percentage, are: 18% high borosilicate frit, 10% quartz, 11% calcite, 7% talc, 18% spodumene, 5% calcined zinc, 14% potassium feldspar, 7% jiepai clay, 7% titanium dioxide, 1% bismuth oxide, and 2% cobalt blue.

[0047] Comparative Example 2 Compared with Example 1, Comparative Example 2 differs in that the base glaze material and the top glaze material are different, while the rest are the same as Example 1.

[0048] The base glaze raw materials, calculated by weight percentage, are: potassium feldspar 10%, nepheline 8%, quartz 15%, calcite 20%, dolomite 7%, calcined zinc 4%, barium carbonate 10%, jiepai clay 10%, iron oxide red 11.7%, manganese carbonate 4%, and cobalt oxide 0.3%. The raw materials for the glaze, calculated by weight percentage, are: 20% high borosilicate frit, 10% quartz, 10% calcite, 5% talc, 15% spodumene, 5% calcined zinc, 15% potassium feldspar, 7% jiepai clay, 5% titanium dioxide, 6% bismuth oxide, and 2% cobalt blue.

[0049] Comparative Example 3 Compared with Example 1, Comparative Example 3 differs in that the base glaze material and the top glaze material are different, while the rest are the same as Example 1.

[0050] The base glaze raw materials, calculated by mass percentage, are: 22% low-temperature frit, 18% potassium feldspar powder, 15% quartz powder, 13% calcite powder, 4% wollastonite powder, 2% calcined talc powder, 7% barium carbonate, 7% zinc oxide, 7% argillaceous clay, and 5% iron oxide red. The raw materials for the glaze, calculated by mass percentage, are: 27% low-temperature frit, 17% albite powder, 17% quartz powder, 15% calcite powder, 2.5% dolomite powder, 8.5% barium carbonate, 2.5% zinc oxide, 4.5% argillaceous clay, 3% zirconium silicate, and 3% vanadium blue.

[0051] The ceramic products prepared in Example 1 and the comparative example were subjected to dishwasher tests under the following conditions: 1. Test equipment and media Test instrument: Siemens Clean Magic Box 3.0 (model: SJ43EB11MC).

[0052] Detergent: Dishwasher-specific cleaner and rinse must be used.

[0053] Sample quantity: One product was used as an unwashed reference sample, and another product was placed in the dishwasher for washing. Other empty spaces were filled with ordinary ceramic plates and bowls to simulate the daily life scenario of using a dishwasher. The test sample was washed without stopping the machine. The sample was taken out every 10 times to observe the changes in the glaze. The test was stopped when a visible change was observed, or when no visible change was observed after 200 tests.

[0054] 2. Specific procedures and standards for a dishwasher test: A. Start the dishwasher. After automatically draining water for 30 seconds, start filling with water (2.5L±0.2) and add dishwasher detergent (10g±0.5). B. Water circulates in the tank and begins heating to the target temperature (65℃±2). Once the target temperature is reached, heating stops and rinsing begins for 6 minutes. If the temperature drops, the heating will automatically adjust back to the target temperature. C. After rinsing for 6 minutes, start draining for 30 seconds; D. Rinse: Intake water (2.5L±0.2), rinse for 1 minute without heating, then drain for 30 seconds; E. When the water level reaches 2.5L-3.0L, the circulation pump will start and enter the cleaning mode. The water temperature will be heated to the target temperature (70℃±2). The circulation pump will clean for 15 minutes and then drain for 30 seconds. F. Drainage completed, drying and exhaust: The equipment stops operating when the temperature drops to 30℃.

[0055] Images of the ceramic products prepared in Example 1, Comparative Example 1, and Comparative Example 2 before and after testing are shown below. Figure 1-3 As shown, the ceramic product of Example 1 exhibits a standard, rich reaction effect and excellent gloss. After 200 dishwasher tests, the glaze gloss, effect, and color remained unchanged.

[0056] Compared to the ceramic products in Comparative Example 1, the kiln transformation effect was not obvious, the color was grayish, and the wire-drawing effect was not pronounced. After 120 dishwasher tests, the glaze gloss began to decrease.

[0057] In Comparative Example 2, the ceramic product shows visible glaze shrinkage points in the bowl, and the glaze surface is glossy. After 170 dishwasher cycles, the product's glaze gloss began to decrease, and mottled fading and other phenomena appeared.

[0058] The firing range of Comparative Example 3 is narrower, and the appearance of ceramic products under the same kiln conditions is different. Some of them have darker colors, and the glaze gloss begins to decrease after 120 dishwasher tests.

[0059] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of protection of this application is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of one or more embodiments of this application as described above, which are not provided in detail for the sake of brevity.

[0060] One or more embodiments in this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of this application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of one or more embodiments in this application should be included within the protection scope of this application.

Claims

1. A type of glaze with dramatic kiln transformation, characterized by: The raw materials include the following components by weight percentage: Base glaze raw materials: potassium feldspar 15-20%, nepheline 5-10%, quartz 15-20%, calcite 20-25%, dolomite 3-5%, calcined zinc 2-4%, barium carbonate 12-15%, jiepai clay 8-12%, colorant 12.2-19.3%; Glaze raw materials: 15-20% high borosilicate frit, 10-13% quartz, 10-15% calcite, 5-8% talc, 15-20% spodumene, 5-7% calcined zinc, 14-20% potassium feldspar, 7-10% glaze clay, 5-8% titanium dioxide, 2-5% bismuth oxide, and 1-3% colorant.

2. The intensely kiln-transformed glaze as described in claim 1, characterized in that, The raw materials include the following components by weight percentage: Base glaze raw materials: potassium feldspar 15%, nepheline 7%, quartz 17.7%, calcite 22%, dolomite 3%, calcined zinc 2%, barium carbonate 13%, jiepai clay 8%, colorant 12.3%; Glaze raw materials: 18% high borosilicate frit, 10% quartz, 11% calcite, 5% talc, 18% spodumene, 5% calcined zinc, 14% potassium feldspar, 7% jiepai clay, 6% titanium dioxide, 4% bismuth oxide, and 2% colorant.

3. The intensely kiln-transformed glaze as described in claim 1 or 2, characterized in that, The colorants in the base glaze raw material include iron oxide red, manganese carbonate and cobalt oxide, and the colorants in the top glaze raw material are vanadium blue or cobalt blue.

4. The intensely kiln-transformed glaze as described in claim 3, characterized in that, The base glaze raw material comprises the following components by weight percentage: 10-15% iron oxide red, 2-4% manganese carbonate, and 0.2-0.3% cobalt oxide. The colorant in the top glaze raw material is cobalt blue.

5. A method for preparing a violently kiln-transformed glaze as described in any one of claims 1-4, characterized in that, The base glaze material and the top glaze material are added to water separately, wet ball milled, sieved, and adjusted to a suitable concentration to obtain base glaze slurry and top glaze slurry respectively; then the base glaze slurry is applied to the body and dried to form a base glaze layer; then the top glaze slurry is evenly applied on the base glaze layer; and fired in an oxidizing atmosphere at a maximum firing temperature of 1180-1210℃ to obtain a glaze with intense kiln transformation.

6. The preparation method according to claim 5, characterized in that, In wet ball milling, the mass ratio of raw material, ball milling stone, and water is 1:1.5:0.7, and the mixture passes through a 120-mesh sieve.

7. The preparation method according to claim 5, characterized in that, The concentration of the base glaze slurry should be controlled at 35-45 Baume degrees.

8. The preparation method according to claim 5, characterized in that, The concentration of the glaze slurry should be controlled at 55-60 Baume degrees.

9. The preparation method according to claim 5, characterized in that, The base glaze slurry is applied to the body using the dip glazing method, and the top glaze slurry is applied to the base glaze layer using the spray glazing method. After the top glaze slurry is evenly applied to the base glaze layer, it is left to stand for 0.2-0.5 hours.

10. The preparation method according to claim 5, characterized in that, The maximum firing temperature is 1190℃.

Images