UNC JOINT STOCK COMPANY

UNC Joint Stock Company is pleased to introduce to our customers the production process of high-class ceramic products branded UNCVietnam. To make high-quality ceramics, the workman must go through the stages of ing raw materials, processing and mixing raw materials, shaping, patterning, enameling, firing products and finally ing finished products with pepper. high standard. The life-giving experience of people who make ceramics is "One bone, two skin, third one furnace".

Porcelain potters perceive ceramics artifacts as a living body, a miniature universe in which the harmonious combination of the Five Elements (五行) is metal (金), carpentry (木), water (水), fire (火) and earth (土). The development of the profession is seen as the comm of the Five Elements and the comm of the Five Elements is located in the creative labor process with strict, precise technical processes.

Step 1: Choose ingredients

s The first important thing to form ceramics kilns is the source of the material. The UNC divides two elements that make up ceramic products: Earth and Glaze.

+ Your land is made up of 3 main elements: clay, kaolin and agar

Clay is the part that creates the toughness of the material to facilitate shaping. The main components of Clay are Al2O3 and Si2O3. The composition of different types of clay is very little. The big difference lies in the small size of the soil. Currently UNC products use materials with a soil screening standard of less than 10 nanometers. We are one of the few units in the country to use such fine clay. S

Cao lanh là thành phần chính quan trọng nhất để làm ra sản phẩm của gốm sứ. nó cùng với men và một số yếu tố khác có ảnh hưởng chính đến độ bền, đẹp vào cao cấp và giá thành của sản phẩm. Các nhà sản xuất trong nước và trên thế giới đều giữ những bí quyết riêng về thành phần và hạn lượng cao lanh và tràng thạch mình sử dụng trong xương đất. Các sản phẩm của công ty UNC được sử dụng từ nguồn nguyên liệu cao lanh nhập khẩu từ nước ngoài là chủ yếu( từ Ấn độ, Băng la đét, Indonesia...). Thành phần chính của cao lanh là: SiO2, Al2O3, H2O, ngoài ra còn có một lượng nhỏ tạp chất Fe, Ti, K và Mg. cao lanh có màu trắng, trắng xám, dạng đặc sít hoặc là những khối dạng đất sáng màu, tập vảy nhỏ, tinh thể đơn vị dạng hình lục lăng liên kết thành các tấm nhỏ. Trong các thành phần trên có hai thành phần chính chúng tôi luôn khống chế là: Al2O3 khống chế từ 35% -42%,Ti khống chế từ 1%-1,4% bổ xung từ quặng petalite. Hai thành phần đó tạo lên độ sáng trắng của sản phẩm và có khả năng thấu quang(nhìn xuyên qua được vật dụng trước ánh sáng). Nhiệt độ kết khối của Cao lanh từ 1700-18000C. Các sản phẩm gốm sứ UNCVietnam từ cao lanh có độ trắng từ 88% đến 92% trên thang độ trắng 100. Cao lanh thường chiếm khoảng 45%-60% xương đất.

+ Porcelain enamel: nature is glass. Porcelain enamel is a complex system of many oxides such as Li2O, Na2O, K2O, Ba2O3, CaO, ZnO, MgO, Al2O3, Fe2O3, SiO2 ...: made from mixing kaolin, clay ... also known as the main component agar field KAlSi3O8, NaAl2Si2O8 or LiAlSi4O10 and other components. The rock is added to the soil with the main purpose of reducing the temperature of the kaolin. Use potassium agar. And often use 2 sources of raw materials from India and Viet Tri, Phu Tho. Sandstone usually accounts for about 10% of the soil bone

Optical porcelain porcelain brings more mysterious beauty.

Li2O is used in fixed quantities to create the hardness of the enamel surface and increase the penetration of the enamel, highlighting the quality of the internal soil bone. Both enamel and soil bones have brought high visibility to UNCVietnam products.

We absolutely do not use PbO (lead oxide) and Cd in yeast. This reduces the gloss of enamel but is very safe for health. The results of the testing of the ingredient alone are absolutely free of these 2 toxic components.

My side also applies Nano filter to filter yeast. So the surface of my product is as smooth as high-class products of China and Minh Long when using Frit enamel. Using frit enamel for products with high gloss and smoothness, but the hardness of enamel is not good. should be easily scratched during use. This just takes a while to see the difference.

Step 2: Handling and mixing soil

In soil, there are often impurities, in addition, depending on the requirements of different types of ceramics, there may be different ways of preparing the soil to create a suitable product. In Bat Trang, traditional soil treatment is through water immersion in a tank system, consisting of 4 tanks at different heights.

The first tank at the highest position is the "wharf" used to soak raw clay and water (soaking time is about 3-4 months). The clay under the action of water will break down its original grain structure and begin the decay process (folk called long soaking to break the soil). When the soil is "ripe" (traditionally called), beat the soil evenly, thoroughly so that the soil particles really dissolve in the water to form a liquid mixture. Then remove this liquid mixture into a second tank called a "settling tank" or "filtration tank". Here the clay begins to settle, some impurities (especially organic matter) emerge, proceed to remove them.

After that, scoop the thin tank from the settling tank to the third tank called "drying tank", Bat Trang people usually dry the soil here for about 3 days, then transfer the soil to the fourth tank as "composting tank". In the incubation tank, iron oxides (Fe2O3) and other impurities are reduced by fermentation method (ie the process of microorganisms reducing harmful substances in the soil). Incubation time as long as possible.

In general, the processing stage of Bat Trang potters often does not go through many complicated stages. In the process of processing, depending on the type of pottery, one can add kaolin to a different or lesser degree.

Step 3: Pose the product

The traditional method of shaping Bat Trang villagers is by hand-made on the turntable. In the shaping stage, Bat Trang potters popularly use the "hand strokes, beers" on the turntable, previously this work was often undertaken by women. Workers sit on a chair higher than the table and then use a rotating foot to rotate the product and hands to shape the product. The soil before being put into the turntable is finely crushed, rolled into a ball and then thrown ("catching") to shorten. Then people put in the middle of the turntable, pat the soil to stick and then hybridize and pull the plastic soils to "beat" the soil and "incense" primarily with two fingers on the right. After the process of pulling the soil by hand and crockery to the extent necessary, the worker will use the earthenware to shape the product. "Trimmers" and "catch" After that, they will cut off their legs and put them on the "groove". The use of the women with a rotating turntable to create the original shape of the product is a common job common in every ancient pottery in Vietnam (not only Bat Trang) but very strange to some Western potters. However, this technique has been lost and now there are no more Bat Trang potters who can do this job. "Be chạch" is also a form of product claw on a slight turntable and mainly by men.

Pottery "builder" pottery workers are highly technical and artistic. Sometimes they shape a complete ceramic product, but sometimes they shape each individual part of a product and then conduct a piecing together. Currently, according to the requirements of industrial or fine art pottery production, artisans can mold and mold a sample product to plaster plaster for mass production.

Shaping ceramic products in printed molds (plaster mold or wooden mold) is carried out as follows: place the mold in the middle of the turntable, pin it tightly, smooth the mold and throw the product in the middle of the mold to hold the legs firmly , dredge dirt on the rim, turn the turntable and pull the handle to the point necessary to create the product. Nowadays, Bat Trang people use common techniques of "casting" artifacts. If you want to have ceramic artifacts in the casting technique, you must first make plaster mold. Molds are simple to complex. The simple type is a double-sided mold, while the more complex one often has more gills, depending on the shape of the product being created. How to create this design at the same time can create the same series of products, very quickly and easily. In addition, people also use the method of pouring: pouring "excess lakes" or "full lakes" to shape the product.

Step 4: Repairing carpentry and 1st roasting (preheating)

Shaping carpentry products should be "incubated" and repaired to complete. The potter put the product on but the turntable turned slightly and then turned the turntable and gently pushed on the stature of the scales to use the scales, using the drumstick to pat the "stature" of the soil to the "stature" of the legs and tighten the product. again (called "draining"). The potter performs the operations of cutting, removing the excess, accreting the defect, assembling parts of the product (such as taps, separators ...), drilling holes in the products, trimming the flower contours. Literature and water arts for smooth face products. Products that are modified without using a turntable are called "making in series"; must use a turntable called "making a table".

According to decoration requirements, you can add more soil to some areas of the product and then pruning it to create shapes (making reliefs), sometimes having to carve deeply decorative decorations on the surface of the product ...

Carrying out the first heating of the wood at 550oC to dry and burn out the organic impurities in the soil, the carpentry is stiffer to ensure the implementation of the next stages without damage to the product shape.

Step 5: The process of decorating patterns and enamelling 
Drawing techniques 
The artist uses a brush to draw directly on the rustic background of textured patterns. Pottery artists must be skilled, the pattern must be in harmony with the shape of the pottery, the decorative motifs have raised pottery to an artistic level, each of which is a work. Bat Trang potters also used many other forms of decoration, with artistic effects such as sewing thread, smeared glaze, painting glaze ...

Recently, Bat Trang appeared a technique of painting on the first baked ceramic bone or flower-steaming technique, a pre-printed decoration on decal paper, imported from abroad. These two types are beautiful but not traditional of Bat Trang. These types are not considered artistic and creative in Bat Trang pottery heritage, as well as Vietnamese pottery in general.

Decorative textures need workers to have a high aesthetic eye

Enamel

When the finished product is finished, the potter can preheat the product at a low temperature and then enamel it or use the finished wood product directly to enamel on it before firing. Bat Trang potters often choose the method of enameling directly on the finished carpentry products. Rustic products before enameling must be cleaned with dust brush. Products of the ceramic bone color before glaze must have a glaze lining to cover the color of the ceramic bone, and must also calculate the performance of each type of enamel to cover each type of ceramic bone, glaze concentration, weather and difficulty level of ceramic bone ... Glazing technique takes many forms such as spraying enamel, pouring enamel onto a large ceramic surface, dipping enamel for small but most common type of glaze. In addition to the product, called "enamel pliers", and the most difficult is the form of "rotating enamel" and "casting enamel". Rotating enamel is a form of enamelling inside and outside the product at the same time, while casting enamel, only enameling inside the product. These are the enamelling tactics of Bat Trang potters, both technical and artistic, preserved over many generations, even a secret in the profession here.

Fix yeast products

The potter proceeded to finalize the product before putting it in the furnace. Firstly, you have to carefully look at each product to see if there are any defects in the enamel. They then proceed to "trim" that is to remove any excess glaze, which is called "fixing yeast products".