Week 8 Readings
2. Watch a video: Crafting Luxury The Secrets Behind China's Exquisite Porcelain
Transcript: Watch a video: Crafting Luxury The Secrets Behind China's Exquisite Porcelain
This video documents the production process at Shenzhen Guoci Yongfengyuan Porcelain Industry Co., Ltd.
Guoci Yongfengyuan was established during the Qianlong era of the Qing Dynasty (1795) and has been passed down through five generations. It is a comprehensive ceramic enterprise integrating raw materials, research and development, design, production, marketing, and the promotion of ceramic culture.
The company employs over 4,000 people and produces household porcelain, gift porcelain, hotel porcelain, and collectible porcelain. With an annual output of approximately 30 million pieces, its products are exported to more than 40 countries and regions. The company has also undertaken research and design work for porcelain used at major national events.
Design and Research
Decal R&D Laboratory
Designers develop ceramic patterns and decorative styles.
Printing Workshop
Decorative designs are prepared for transfer application.
Glaze Formula Laboratory
Glaze recipes are tested and adjusted. Flow rate tests are conducted to ensure proper glaze consistency.
Raw Material Processing
Grinding and Mixing
Raw materials are ground and mixed in industrial grinders.
Bone China Grinding Workshop
Raw materials undergo ball milling, vibration screening, and filter pressing. The processed slurry is stored in underground tanks for thorough mixing and aging.
White and black slips are tested for flow rate. Slip from storage tanks is dewatered using filter presses, and clay cakes are removed for further processing.
Forming and Molding
Isostatic Pressing
Ceramic isostatic pressing machines enable automated production from feeding to forming.
Mold Manufacturing Workshop
Plaster molds are produced and stored. Plaster slurry is poured into molds, and vent rods are inserted to assist air release during demolding. After approximately three minutes, the plaster solidifies and the mold is trimmed.
Slip Casting
Slip is poured into plaster molds. After setting, excess slip is poured out. Once sufficiently firm, the molds are opened and the formed pieces are removed.
Jiggering Forming Workshop
Mechanical forming methods shape round ceramic forms.
Drying Ovens
Formed pieces are dried before firing.
Firing Processes
Bisque Firing
Ceramics are bisque-fired at temperatures between approximately 980°C and 1280°C. This process increases the mechanical strength of the ceramic body and reduces damage during glazing.
After bisque firing, pieces undergo inspection.
Glazing
Surface Preparation
Polishing and washing improve glaze adhesion.
Glaze Spraying
Interior glaze is applied to specific forms, such as liquor bottles.
In some cases, the ceramic body is preheated to approximately 100–120°C before glaze spraying. This promotes better glaze adhesion. After glazing, pieces undergo high-temperature glaze firing, typically above 1300°C.
After glaze firing, products are inspected again.
Decoration and Gold Application
Decal Application
Ceramic decals are applied to the glazed surface. After decal application, the pieces are fired again.
Gold Tracing
Artisans apply gold decoration using gold paste containing real gold. The uniformity of gold lines is inspected using focused lighting.
After gold decoration, the pieces undergo an additional firing.
Quality Control
Final Product Inspection
Finished products are carefully examined for defects.
Heavy Metal Testing
Laboratory testing ensures compliance with safety standards. An Atomic Absorption Spectrophotometer is used to measure the presence of metallic elements such as lead and cadmium.
Samples with decals are soaked in 4% acetic acid solution to produce leachate. The leachate is then analyzed to determine heavy metal content.
Packaging
Products that do not meet quality standards are discarded. Approved products are sent to the packing workshop for final packaging.