Jianshui purple pottery firing method capable of producing jade green color effect

Abstract

A kind of Jian Shui purple pottery firewood firing method for burning out jade green effect, the method is according to 50-85 parts of white clay, 15-40 parts of loess, 5-30 parts of purple clay to prepare red mud raw material, after mud preparation and mud refining, blank pulling, base repairing, it is placed in firewood kiln for firewood firing, reduction firing is carried out by closing firewood kiln, the wood for combustion is pine, the firing temperature is 1150 DEG C~1270 DEG C, the firing time is 72~120 hours, then cooling out of furnace, the Jian Shui purple pottery product with green fire-facing surface, backfire surface for gold red or brown red effect is obtained.The Jian Shui purple pottery product prepared by the present application has rich color change, the product looks like a jade on one side, like a jade on the other side, and shows the fantastic effect of shining scales, which is completely different from the effect of traditional purple pottery products, and is deeply loved by people.

Description

Technical Field

[0001] This invention belongs to the field of Jianshui purple pottery firing technology. Background Technology

[0002] Wood firing is an ancient method of ceramic firing, characterized by the use of wood as fuel to fire ceramics in an open kiln. Wood-fired ceramics possess a glaze effect created by naturally falling ash, resulting in a deep, warm, and richly layered glaze that evokes a rustic and natural feel. Furthermore, the flames and temperature variations produced by the burning wood during the firing process affect the ceramic body and glaze, creating textures that can be smooth or rough, as well as variations in color. The wood ash and charcoal residue from the burning wood settle on the ceramic surface, forming a natural ash glaze. This glaze color is unique, making each piece distinctive.

[0003] Jianshui purple pottery, one of China's four famous pottery styles, uses clay made from white clay, yellow clay, five-colored clay, blue clay, and purple clay. The traditional Jianshui purple pottery red clay formula uses natural clay raw materials from Jianshui County, Yunnan Province, in a ratio of 10 parts white clay, 17 parts purple clay, 17 parts yellow clay, 20 parts blue clay, and 36 parts five-colored clay. Due to its high iron content, it produces a unique black or golden-gray glaze effect when wood-fired, which is highly accepted in the market. However, it still has some shortcomings. First, it is difficult to produce the desired green-red color variations. Second, the firing temperature is low (1150℃~1180℃), and the high temperature during wood-firing easily leads to overfiring, causing the ceramics to bulge and become defective. This results in a high number of defective products, a low rate of high-quality pieces, and high costs. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for firing Jianshui purple pottery by wood firing that can produce the green and red color-changing effects that people like and reduce the scrap rate.

[0005] The technical solution adopted in this invention is as follows:

[0006] A wood-fired method for producing Jianshui purple pottery with a jade-green color is described below:

[0007] (1) Preparation of red clay raw materials: by mass, the red clay raw materials consist of 50-85 parts of white clay, 15-40 parts of yellow clay, and 5-30 parts of purple clay;

[0008] (2) Clay preparation and clay refining: Mix the prepared red clay raw materials with water, press and filter, and then vacuum refining 2 to 5 times to obtain pottery clay material;

[0009] (3) Throwing: Throw the clay to obtain a wet clay blank of the desired shape, and let it air dry;

[0010] (4) Trimming: Trimming the surface of the air-dried clay blank;

[0011] (5) Firing: The trimmed clay blanks are placed in a wood-fired kiln and the kiln is sealed for reduction firing. The wood used for burning is pine. The firing temperature is 1150℃~1270℃ and the firing time is 72~120 hours.

[0012] (6) Cooling and removing from the kiln: After the fired objects are cooled in the kiln, the kiln door is opened and the fired objects are taken out, resulting in Jianshui purple pottery products with a green front side and a golden red or brownish red back side.

[0013] The red clay material formula of the present invention has the following characteristics:

[0014] 1. The specific formula of this invention is different from the traditional Jianshui purple pottery red clay formula. A large amount of white clay is added to the formula. The white clay contains a lot of sand, has a high silica content, and has high viscosity at high temperatures. The wood ash is easily adsorbed on the surface, producing a better ash glaze effect.

[0015] 2. The specific formula of this invention differs from the traditional Jianshui purple clay red clay formula. It introduces iron (1%-5%) by adding appropriate amounts of purple clay and yellow clay. During wood firing, the fire-facing surface absorbs a large amount of wood ash. Due to the low iron content in the body, high-temperature reduction does not affect the loose clay ash glaze effect, which is beneficial for the product to exhibit a green effect. Simultaneously, the unfired surface absorbs less wood ash, and high-temperature reduction is beneficial for exhibiting a golden-red or brownish-red effect on the body.

[0016] 3. The specific formula of this invention differs from the traditional Jianshui purple pottery red clay formula. It does not use the low-temperature raw materials (blue clay and five-colored clay) in Jianshui purple pottery, and the amount of white clay used is much higher than in existing red clay formulas, which helps to resist high temperatures. It is less prone to bulging or deformation during high-temperature reduction, greatly improving the yield of Jianshui purple pottery and reducing production costs. Combined with the use of pine wood for wood firing in a reducing atmosphere, and reasonable control of firing temperature and firing time, the thicker ash produced by the burning wood results in products with a green front side and a golden-red or brownish-red back side, which has an excellent appearance and is very popular. Attached Figure Description

[0017] Figure 1 This is a photograph of the fire-facing side of a Jianshui purple pottery product fired using the method of this invention;

[0018] Figure 2 This is a photograph of the unfired side of a Jianshui purple pottery product fired using the method of this invention.

[0019] Figure 3 This is a photograph of the fire-facing side of another Jianshui purple pottery product fired using the method of this invention;

[0020] Figure 4 This is a photograph of the unfired side of another Jianshui purple pottery product fired using the method of this invention. Detailed Implementation

[0021] The invention and its technical effects are further illustrated below with reference to specific embodiments. Example 1

[0022] The wood-firing method for Jianshui purple pottery that can produce a jade-green color effect is as follows:

[0023]

[0024] (1) Preparation of red clay raw materials: Weigh the following raw materials in parts by weight: 80 parts white clay, 15 parts yellow clay, and 5 parts purple clay from Jianshui County. Their chemical composition is shown in the table below:

[0025] (2) Clay preparation and kneading: Using traditional techniques, the prepared red clay raw materials are mixed with water and stirred, filtered, and then kneaded under vacuum four times to obtain pottery clay.

[0026] (3) Throwing: Throw the clay to obtain a wet clay blank of the desired shape, and let it air dry;

[0027] (4) Trimming: Trimming the surface of the air-dried clay blank;

[0028] (5) Firing: The trimmed clay blanks are placed in a wood-fired kiln and fired in a strong reducing atmosphere. The wood used for firing is pine. The firing temperature is 1170℃~1270℃ and the firing time is 90 hours.

[0029] (6) Cooling and removing from the kiln: After the fired objects have cooled in the kiln, the kiln door is opened, and the fired objects are removed to obtain the following: Figure 1 , Figure 2 The Jianshui purple pottery products shown. Figure 1 The product's fire-facing surface is green, and due to the thicker ash from wood firing and the higher firing temperature, a wavy glaze naturally forms. Figure 2 The product's unfired surface reveals a subtle dark reddish-gold effect, naturally forming a wavy glaze. The overall appearance of the product creates a fantastical effect, resembling jade on one side and shimmering with scales on the other, completely different from traditional purple clay products, making it very popular. Example 2

[0030] A wood-fired method for producing Jianshui purple pottery with a jade-green effect. In this method, steps (2), (3), (4), and (6) are the same as in Example 1, except that the red clay raw material prepared in step (1) is composed of 55 parts white clay, 35 parts yellow clay, and 10 parts purple clay sourced from Jianshui County. Its chemical composition is shown in the table below:

[0031] Step (2) involves vacuum kneading the clay five times.

[0032] The sintering temperature range for step (5) is 1210℃~1260℃. The firing time is 100 hours.

[0033] Get as Figure 3 , Figure 4 The Jianshui purple pottery products shown. Figure 3 The product's fire-facing surface is dark green, and due to the thick ash from wood firing and the high firing temperature, a wavy glaze naturally forms. Figure 4 The product's unexposed side has a brownish-red effect, which also naturally forms a wavy glaze, giving the product a very beautiful appearance. Example 3

[0034] A wood-fired method for producing Jianshui purple pottery with a jade-green effect. In this method, steps (2), (3), (4), and (6) are the same as in Example 1, except that the red clay raw material prepared in step (1) is 70 parts white clay, 15 parts yellow clay, and 15 parts purple clay sourced from Jianshui County. Its chemical composition is shown in the table below:

[0035] Step (2) involves vacuum kneading the clay twice.

[0036] The sintering temperature range for step (5) is 1180℃~1250℃. The firing time is 120 hours. Example 4

[0037] A wood-fired method for producing Jianshui purple pottery with a jade-green effect. In this method, steps (2), (3), (4), and (6) are the same as in Example 1, except that the red clay prepared in step (1) is made from 65 parts white clay, 35 parts yellow clay, and 5 parts purple clay sourced from Jianshui County. Its chemical composition is shown in the table below:

[0038] The sintering temperature range for step (5) is 1160℃~1270℃. The firing time is 72 hours.

[0039] The above embodiments are only some embodiments of the present invention and are not intended to limit the scope of protection of the present invention. All equivalent substitutions based on the technical solutions of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A wood-fired method for producing Jianshui purple pottery with a jade-green color, characterized in that, The method is as follows: (1) Preparation of red clay raw materials: by mass, the red clay raw materials consist of 50-85 parts of white clay, 15-40 parts of yellow clay and 5-30 parts of purple clay, all sourced from Jianshui County. (2) Clay preparation and clay refining: Mix the prepared red clay raw materials with water, press and filter, and then vacuum refining 2 to 5 times to obtain pottery clay material; (3) Throwing: Throw the clay to obtain a wet clay blank of the desired shape, and let it air dry; (4) Trimming: Trimming the surface of the air-dried clay blank; (5) Firing: The trimmed clay blanks are placed in a wood-fired kiln and the kiln is sealed for reduction firing. The wood used for burning is pine. The firing temperature is 1150℃~1270℃ and the firing time is 72~120 hours. (6) Cooling and removing from the kiln: After the fired objects are cooled in the kiln, the kiln door is opened and the fired objects are taken out, resulting in Jianshui purple pottery products with a green front side and a golden red or brownish red back side.

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