Manufacturing method of Longquan celadon decorative plate

Abstract

The invention relates to a manufacturing method of a Longquan celadon decorative plate. A green body of the Longquan celadon decorative plate is prepared from the following raw materials in percentage by weight: 50-70% of Longquan soil, 10-30% of malayan soil, 5-25% of quartz, 2-6% of bentonite, 0.01-0.05% of additional sodium oleate and 0.01-0.05% of PVA (Polyvinyl Alcohol). The glaze comprises the following raw materials in percentage by weight: 6-12% of Zijin clay, 8-15% of quartz, 35-55% of potassium feldspar, 10-15% of calcite, 5-14% of calcined talc, 8-15% of calcined kaolin, 0.5-2% of ferric oxide and 0.1-0.2% of additional sodium tripolyphosphate. The Longquan celadon decorative plate is obtained through the working procedures of blank material glaze preparation, blank body forming, drying, biscuit firing, glazing and firing. The Longquan celadon decorative plate prepared by the invention is simple in process, low in cost and excellent in quality, so that the Longquan celadon decorative plate has a wide market prospect.

Description

Technical Field

[0001] The invention relates to the technical field of traditional ceramic manufacturing, in particular to a method for manufacturing a Longquan celadon decorative plate. Background Art

[0002] As a treasure of traditional Chinese ceramics, Longquan celadon is world-famous for its jade-like glaze and exquisite craftsmanship. In recent years, with the increasing demand for home decoration, Longquan celadon decorative panels have gradually become the new favorite of the ceramic industry with their unique decorative effects and wide application prospects.

[0003] At present, the production of Longquan celadon basically follows the traditional porcelain making process. The research on the blank glaze formula is based on experience and there is little scientific and systematic research. The blank glaze formula, molding process and firing process of celadon decorative panels have not been systematically and scientifically studied. For example, most of the Longquan celadon glazes belong to feldspar glazes, which have a high expansion coefficient. In addition, a thicker glaze layer is usually applied, which causes a large difference in the expansion coefficient between the glaze and the body. During the firing process, the stress between the body and the glaze will cause the body to be stretched and deformed, resulting in a high deformation rate of the celadon decorative panel after firing. In addition, the high expansion coefficient difference also causes the glaze to crack; the existing blank glaze formula is not compatible with the high-temperature reduction firing technique, resulting in color difference and pinholes on the glaze. In particular, the celadon decorative panel process draws on the traditional porcelain panel production method, that is, the manual rolling molding method. The primary problem of this molding technique is that it does not match the local glaze of Longquan, which leads to many technical problems such as poor flatness, significant color difference, dense pinholes and cracking of the glaze surface. In addition, the manual rolling method is inefficient and cannot meet the actual needs of batch and large-scale production. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method for manufacturing a Longquan celadon decorative plate with simple process, low cost and excellent quality.

[0005] The technical solution of the present invention is: a method for manufacturing a Longquan celadon decorative plate, characterized in that: The raw materials of the green body are composed of the following weight percentages: 50-70% Longquan clay, 10-30% Malay clay, 5-25% quartz, 2-6% bentonite, 0.01-0.05% sodium oleate, and 0.01-0.05% PVA. The glaze raw materials are composed of the following weight percentages: 6-12% purple clay, 8-15% quartz, 35-55% potassium feldspar, 10-15% calcite, 5-14% burnt talc, 8-15% burnt kaolin, 0.5-2% iron oxide, and 0.1-0.2% sodium tripolyphosphate; After the processes of blank and glaze preparation, blank forming, drying, bisque firing, glazing and firing, the Longquan celadon decorative plate is obtained.

[0006] In the blank preparation process, Longquan clay, Malay clay, quartz and bentonite are weighed and mixed according to the blank raw material formula, and are loaded into a ball mill with a material: ball: water ratio of 1:2:1-1.2 for ball milling for 16 hours; sodium oleate and PVA are weighed according to the blank raw material formula, placed in 200 ml of 80°C water, fully stirred and poured into the ball mill for continued ball milling for 2 hours, and the slurry after ball milling is aged for 24 hours and then passed through a 100-mesh sieve, and then dehydrated and kneaded to make mud.

[0007] The moisture content of the mud is 15-20%.

[0008] In the glaze preparation process, the raw materials are weighed and mixed according to the glaze formula, and the raw materials are loaded into a ball mill with a material: ball: water ratio of 1:2:1-1.2 for 10-20 hours. After ball milling, the slurry fineness is less than 0.04% of the residue on a 10,000-hole sieve.

[0009] In the forming process, clay is put into the hopper of a screw extruder, and the shape of the die is adjusted to extrude Longquan celadon decorative slab blanks of different specifications.

[0010] The thickness of the glaze layer in the glazing process is 1.5 to 2.5 mm.

[0011] The temperature of the biscuit sintering process is 700-800° C., and the heat preservation time is 20 minutes.

[0012] The sintering process includes five stages: drying, oxidation, strong reduction, weak reduction and cooling, wherein: in the drying stage, the temperature is raised to 580-600°C in 2-3 hours; in the oxidation stage, the temperature is raised to 980°C in 3-4 hours under an oxidizing atmosphere and kept warm for 10 minutes; in the strong reduction stage, the temperature is raised to 1120-1140°C in 1.5-2 hours under a strong reducing atmosphere; in the weak reduction stage, the temperature is raised to 1280-1310°C in 2.5-3.5 hours under a weak reducing atmosphere; in the cooling stage, the temperature is naturally cooled to room temperature.

[0013] The surface flatness of the Longquan celadon decorative plate: maximum deviation ≤±0.5%, strength: average rupture modulus ≥53N / mm 2 , Thermal stability: No cracking after three cycles from 180℃ to 20℃.

[0014] In order to improve the molding efficiency of Longquan celadon decorative panels, the present invention adopts an extrusion molding method. In order to adapt to the requirements of extrusion molding and the expansion coefficient of Longquan celadon glaze, the present invention adjusts the body formula: first, in order to make the expansion coefficient of the body and the glaze compatible, the body expansion coefficient needs to be increased, that is, Longquan soil with high potassium and sodium content is introduced as the main raw material, but the content of feldspar and quartz minerals in Longquan soil is high, resulting in low plasticity of the body. Therefore, the present invention introduces sodium oleate and PVA as additives in the body formula to reduce drying shrinkage and improve body strength while improving body plasticity. Sodium oleate molecules have hydrophilic groups (carboxyl groups) and hydrophobic groups (hydrocarbon chains), which can be adsorbed on the surface of clay particles. The hydrophilic and hydrophobic groups repel each other, reducing the friction between particles, making clay particles easier to slide, thereby improving the plasticity of the body. After drying, the PVA solution can form a thin and uniform film that covers the surface of the ceramic particles, enhancing the bonding force between the particles, improving the density and strength of the green body, and making the green body less likely to crack or deform during the molding and drying process, thus solving the shortcoming of low yield in the current production of Longquan celadon decorative panels.

[0015] The formula of the Longquan celadon decorative plate involved in the present invention breaks through the limitation of using local raw materials in Longquan. The body and glaze formulas all adopt common mineral raw materials and chemical raw materials. The products have uniform color and jade-like texture, good thermal stability and wide adaptability. Sodium oleate and PVA are introduced into the body formula involved, which not only increases the plasticity of the blank but also adapts to the expansion coefficient of the glaze, so that it can maintain good flatness during extrusion molding, is not easy to crack or deform, improves the product yield, and increases the product profit margin, and therefore has broad market prospects. DETAILED DESCRIPTION

[0016] In order to further explain the present invention and the technical means and effects adopted to achieve the predetermined invention purpose, the present invention is described in detail below in conjunction with preferred embodiments: The chemical compositions of the mineral raw materials quartz, potassium feldspar, burned talc, calcite, purple clay, burned kaolin, iron oxide, Malay clay, Longquan clay, and bentonite used in the present invention are as follows:

[0017] Example 1 A method for manufacturing a Longquan celadon decorative plate, wherein the raw materials of the green body are composed of the following weight percentages: 50% Longquan clay, 23% Malay clay, 25% quartz, 2% bentonite, and additionally 0.01% sodium oleate and 0.01% PVA; The glaze raw materials are composed of the following weight percentages: 6% purple clay, 8% quartz, 55% potassium feldspar, 10% calcite, 5.5% burnt talc, 15% burnt kaolin, 0.5% iron oxide, and 0.1% sodium tripolyphosphate; After the processes of blank and glaze preparation, blank forming, drying, bisque firing, glazing and firing, the Longquan celadon decorative plate is obtained.

[0018] In the blank preparation process, Longquan clay, Malay clay, quartz, and bentonite are weighed and mixed according to the blank raw material formula, and are loaded into a ball mill at a material: ball: water ratio of 1:2:1 for ball milling for 16 hours; sodium oleate and PVA are weighed according to the blank raw material formula, placed in 200 ml of 80°C water, fully stirred, and poured into the ball mill for continued ball milling for 2 hours. After ball milling, the slurry is aged for 24 hours and then passed through a 100-mesh sieve, and then dehydrated and kneaded to make mud.

[0019] The moisture content of the mud is 18%.

[0020] In the glaze preparation process, the raw materials are weighed and mixed according to the glaze formula, and are loaded into a ball mill with a material: ball: water ratio of 1:2:1 for 10 hours. After ball milling, the slurry fineness is less than 0.04% of the residue on a 10,000-hole sieve.

[0021] In the forming process, clay is put into the hopper of a screw extruder, and the shape of the die is adjusted to extrude Longquan celadon decorative slab blanks of different specifications.

[0022] The thickness of the glaze layer in the glazing process is 1.5 mm.

[0023] The temperature of the biscuit firing process is 700° C. and the holding time is 20 minutes.

[0024] The sintering process includes five stages: drying, oxidation, strong reduction, weak reduction and cooling, wherein: in the drying stage, the temperature is raised to 580°C in 2 hours; in the oxidation stage, the temperature is raised to 980°C in 3 hours under an oxidizing atmosphere and kept warm for 10 minutes; in the strong reduction stage, the temperature is raised to 1120°C in 1.8 hours under a strong reducing atmosphere; in the weak reduction stage, the temperature is raised to 1300°C in 2.5 hours under a weak reducing atmosphere; in the cooling stage, the temperature is naturally cooled to room temperature.

[0025] The surface flatness of the product obtained in this embodiment: maximum deviation ≤±0.5%, strength: average rupture modulus = 53.7N / mm 2 , Thermal stability: No cracking after three cycles from 180℃ to 20℃.

[0026] Example 2 A method for manufacturing a Longquan celadon decorative plate, wherein the raw materials of the green body are composed of the following weight percentages: 59% Longquan clay, 30% Malay clay, 6% quartz, 5% bentonite, and additionally 0.02% sodium oleate and 0.02% PVA; The glaze raw materials are composed of the following weight percentages: 12% purple clay, 15% quartz, 35% potassium feldspar, 15% calcite, 10% burned talc, 12% burned kaolin, 1% iron oxide, and 0.15% sodium tripolyphosphate; After the processes of blank and glaze preparation, blank forming, drying, bisque firing, glazing and firing, the Longquan celadon decorative plate is obtained.

[0027] In the blank preparation process, Longquan clay, Malay clay, quartz, and bentonite are weighed and mixed according to the blank raw material formula, and are loaded into a ball mill at a material: ball: water ratio of 1:2:1.1 for ball milling for 16 hours; sodium oleate and PVA are weighed according to the blank raw material formula, placed in 200 ml of 80°C water, fully stirred, and poured into the ball mill for continued ball milling for 2 hours. After ball milling, the slurry is aged for 24 hours and then passed through a 100-mesh sieve, and then dehydrated and kneaded to make mud.

[0028] The moisture content of the mud is 15%.

[0029] In the glaze preparation process, the raw materials are weighed and mixed according to the glaze formula, and are loaded into a ball mill with a material: ball: water ratio of 1:2:1.1 for 15 hours. After ball milling, the slurry fineness is less than 0.04% of the residue on a 10,000-hole sieve.

[0030] In the forming process, clay is put into the hopper of a screw extruder, and the shape of the die is adjusted to extrude Longquan celadon decorative slab blanks of different specifications.

[0031] The thickness of the glaze layer in the glazing process is 2 mm.

[0032] The temperature of the biscuit firing process is 750° C. and the holding time is 20 minutes.

[0033] The sintering process includes five stages: drying, oxidation, strong reduction, weak reduction and cooling, wherein: in the drying stage, the temperature is raised to 590°C in 2.5 hours; in the oxidation stage, the temperature is raised to 980°C in 3.5 hours under an oxidizing atmosphere and kept warm for 10 minutes; in the strong reduction stage, the temperature is raised to 1130°C in 2 hours under a strong reducing atmosphere; in the weak reduction stage, the temperature is raised to 1280°C in 3 hours under a weak reducing atmosphere; in the cooling stage, the temperature is naturally cooled to room temperature.

[0034] The surface flatness of the product obtained in this embodiment: maximum deviation ≤±0.5%, strength: average rupture modulus = 53.9N / mm 2 , Thermal stability: No cracking after three cycles from 180℃ to 20℃.

[0035] Example 3 A method for manufacturing a Longquan celadon decorative plate, wherein the raw materials of the green body are composed of the following weight percentages: 70% Longquan clay, 10% Malay clay, 16% quartz, 4% bentonite, and additionally 0.05% sodium oleate and 0.05% PVA; The glaze raw materials are composed of the following weight percentages: 9% purple clay, 11% quartz, 45% potassium feldspar, 12% calcite, 13% burnt talc, 8% burnt kaolin, 2% iron oxide, and 0.2% sodium tripolyphosphate; After the processes of blank and glaze preparation, blank forming, drying, bisque firing, glazing and firing, the Longquan celadon decorative plate is obtained.

[0036] In the blank preparation process, Longquan clay, Malay clay, quartz, and bentonite are weighed and mixed according to the blank raw material formula, and are loaded into a ball mill at a material: ball: water ratio of 1:2:1.2 for ball milling for 16 hours; sodium oleate and PVA are weighed according to the blank raw material formula, placed in 200 ml of 80°C water, fully stirred, and poured into the ball mill for continued ball milling for 2 hours. After ball milling, the slurry is aged for 24 hours and then passed through a 100-mesh sieve, and then dehydrated and kneaded to make mud.

[0037] The moisture content of the mud is 20%.

[0038] In the glaze preparation process, the raw materials are weighed and mixed according to the glaze formula, and are loaded into a ball mill with a material: ball: water ratio of 1:2:1.2 for 20 hours. After ball milling, the slurry fineness is less than 0.04% of the residue on a 10,000-hole sieve.

[0039] In the forming process, clay is put into the hopper of a screw extruder, and the shape of the die is adjusted to extrude Longquan celadon decorative slab blanks of different specifications.

[0040] The thickness of the glaze layer in the glazing process is 2.5 mm.

[0041] The temperature of the biscuit firing process is 800° C. and the holding time is 20 minutes.

[0042] The sintering process includes five stages: drying, oxidation, strong reduction, weak reduction and cooling, wherein: in the drying stage, the temperature is raised to 600°C in 3 hours; in the oxidation stage, the temperature is raised to 980°C in 4 hours under an oxidizing atmosphere and kept warm for 10 minutes; in the strong reduction stage, the temperature is raised to 1140°C in 1.5 hours under a strong reducing atmosphere; in the weak reduction stage, the temperature is raised to 1310°C in 3.5 hours under a weak reducing atmosphere; in the cooling stage, the temperature is naturally cooled to room temperature.

[0043] The surface flatness of the product obtained in this embodiment: maximum deviation ≤±0.5%, strength: average rupture modulus = 54.3N / mm 2 , Thermal stability: No cracking after three cycles from 180℃ to 20℃.

Claims

1. A method for manufacturing a Longquan celadon decorative plate, characterized in that: The raw materials of the green body are composed of the following weight percentages: 50-70% Longquan clay, 10-30% Malay clay, 5-25% quartz, 2-6% bentonite, 0.01-0.05% sodium oleate, and 0.01-0.05% PVA. The glaze raw materials are composed of the following weight percentages: 6-12% purple clay, 8-15% quartz, 35-55% potassium feldspar, 10-15% calcite, 5-14% burnt talc, 8-15% burnt kaolin, 0.5-2% iron oxide, and 0.1-0.2% sodium tripolyphosphate; After the processes of blank and glaze preparation, blank forming, drying, bisque firing, glazing and firing, the Longquan celadon decorative plate is obtained.

2. The manufacturing method according to claim 1, characterized in that: In the blank preparation process, Longquan clay, Malay clay, quartz and bentonite are weighed and mixed according to the blank raw material formula, and are loaded into a ball mill with a material: ball: water ratio of 1:2:1-1.2 for ball milling for 16 hours; sodium oleate and PVA are weighed according to the blank raw material formula, placed in 200 ml of 80°C water, fully stirred and poured into the ball mill for continued ball milling for 2 hours, and the slurry after ball milling is aged for 24 hours and then passed through a 100-mesh sieve, and then dehydrated and kneaded to make mud.

3. The manufacturing method according to claim 2, characterized in that: The moisture content of the mud is 15-20%.

4. The manufacturing method according to claim 1, characterized in that: In the glaze preparation process, the raw materials are weighed and mixed according to the glaze formula, and the raw materials are loaded into a ball mill with a material: ball: water ratio of 1:2:1-1.2 for 10-20 hours. After ball milling, the slurry fineness is less than 0.04% of the residue on a 10,000-hole sieve.

5. The manufacturing method according to claim 2, characterized in that: In the forming process, clay is put into the hopper of a screw extruder, and the shape of the die is adjusted to extrude Longquan celadon decorative slab blanks of different specifications.

6. The manufacturing method according to claim 1, characterized in that: The thickness of the glaze layer in the glazing process is 1.5 to 2.5 mm.

7. The manufacturing method according to claim 1, characterized in that: The temperature of the biscuit sintering process is 700-800° C., and the insulation time is 20 minutes.

8. The manufacturing method according to claim 1, characterized in that: The sintering process includes five stages: drying, oxidation, strong reduction, weak reduction and cooling, wherein: in the drying stage, the temperature is raised to 580-600°C in 2-3 hours; in the oxidation stage, the temperature is raised to 980°C in 3-4 hours under an oxidizing atmosphere and kept warm for 10 minutes; in the strong reduction stage, the temperature is raised to 1120-1140°C in 1.5-2 hours under a strong reducing atmosphere; in the weak reduction stage, the temperature is raised to 1280-1310°C in 2.5-3.5 hours under a weak reducing atmosphere; in the cooling stage, the temperature is naturally cooled to room temperature.

9. The manufacturing method according to claim 1, characterized in that: The surface flatness of the Longquan celadon decorative plate: maximum deviation ≤±0.5%, strength: average rupture modulus ≥53N / mm 2 , Thermal stability: No cracking after three cycles from 180℃ to 20℃.

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