Production of Inorganic Pigments in China   

Most inorganic pigments for modern architectural decoration are synthetic inorganic pigments, mainly including: titanium dioxide pigments, iron oxide pigments, chrome pigments and mixed metal oxide (MMO) pigments.

1  Production of inorganic pigments in China

Capacity and output of major inorganic pigments in China in 2010 are listed in Table 1.

Table 1  Capacity and output of major inorganic pigments in China in 2010
Type of pigment    Capacity (t/a)    Output (tons)
Titanium dioxide    2.3 million    1.47 million
Iron oxide    800 000    590 000
Lithopone    300 000    200 000
Chrome pigments    100 000    40 000
Cadmium pigments    50 000     20 000
MMO pigments    3 000    2 000

1)  Titanium dioxide

Titanium dioxide has very good chemical stability. In general conditions, it does not react with most substances. It is an important white pigment for architectural coatings. Compared with other white pigments, it has more superior whiteness, tinting strength, hiding power, weatherability, heat resistance and chemical stability. In particular, it has no toxicity.
   China's titanium dioxide capacity was 2.3 million t/a in 2010. In recent years, with the growing economy, the domestic coatings industry has grown fast, leading to a substantial increase in the production and sales of titanium dioxide. In 2009, China's total titanium dioxide output reached 1.0466 million tons, reaching a record high, increasing by 259 400 tons compared to the previous year, and up 32.9% year on year. Out of the 2009 output, the output of rutile-type titanium dioxide was 552 500 tons, accounting for 52.8% of the titanium dioxide output, increasing by 194 000 tons over the previous year, and up 54.1% year on year: and the output of anatase-type titanium dioxide was 459 800 tons, accounting for 43.9% of the total, increasing by 70 131 tons over the previous year, and up 18.0%. In 2010, China's total titanium dioxide output reached 1.47 million tons, creating a new record.
   At present, a few large-scale chloride process-based titanium dioxide projects are under construction in Sichuan province (Panzhihua area), Yunnan province and Liaoning province (Yingkou area). In the next years, China's chloride process-based titanium dioxide capacity will increase significantly, and product quality will also improve substantially. By 2015, these projects are expected to be completed. By then, China's annual output of titanium dioxide will reach 1.6 million -1.9 million tons.
   Major domestic titanium dioxide producers include: Shandong Dongjia Group, Panzhihua Iron & Steel Group, and Sichuan Lomon Titanium Oxide Co Ltd.

2) Iron oxide

Iron oxide is the second largest inorganic pigment and the largest inorganic color pigment. Iron oxide has a wide range of color spectrum and high hiding power. Its main colors include red, yellow and black. Through proper ways, it can be formulated into orange, brown and green compound pigments. Major varieties of iron oxide pigments include: iron oxide red, iron oxide yellow, iron oxide black, iron oxide blue, iron oxide green, and iron oxide brown. Iron oxide pigments have very good resistance to light, weather, alkali and solvents and also are non-toxic, so they are widely used in architectural coatings and other areas.
   China's output of iron oxide was about 650 000 tons in 2007, about 510 000 tons in 2008 and about 480 000 tons in 2009. Since 2007, it had declined for three years in a row. But since 2010, the output has risen again. The number of orders has increased, and the operating rate of iron oxide pigment producers has also climbed. In 2010, China's output of iron oxide increased to about 590 000 tons. But due to substantial raw material price hikes and other new uncertain factors, the iron oxide pigment sector is still facing a difficult period.
   In addition, the world's four major iron oxide producers, that is, Bayer, Lockwood, Elementis and LANXESS, have all set up factories in China. Their iron oxide capacity in China reaches 120 000 t/a, accounting for 15% of China's total (about 800 000 t/a). Their products are mainly exported to the international market, and their exports account for nearly 50% of China's total iron oxide exports.
   Major domestic iron oxide producers include: Shanghai Yipin Pigments Co Ltd and Changsha Three-ring High-Tech Pigments Co Ltd.

3) Lithopone

Lithopone is a type of non-toxic white powder and insoluble in water. When encountering acids, it can decompose and release hydrogen sulfide. It does not react with hydrogen sulfide or alkali. It features excellent heat resistance, good weatherability, superior whiteness and low cost. Its hiding power is lower than that of titanium dioxide. It is the second most important white inorganic pigment, next only to titanium dioxide.
   In China, there are about 13 lithopone manufacturers, having a total capacity of 300 000 t/a and an annual output of about 200 000 tons in 2010. Major lithopone producers include: Guangzhou Huali Pigment Chemical Co Ltd and Changsha Fengchao Pigment Chemical Co Ltd.

4) Chrome pigments

Chrome pigments are also inorganic pigments, mainly composed of chromates. They are divided into three categories: lead-chrome yellow, molybdate red and anti-rust pigment. These categories are further divided into more than 20 varieties. Chrome pigments feature high tinting strength, good stability and good resistance to light and chemicals. Because chrome pigments have some toxicity, they can only be used in industry and cannot be used in food and toys.
   In China, there are about 16 chrome pigment producers, having a total production capacity of about 100 000 t/a and a total output of 40 000 tons in 2010, of which chrome yellow accounted for 55%, lemon chrome yellow 17%, molybdate red 9%, zinc chrome yellow 3%, and other chromium pigments 16%.
   Major chrome pigment producers include: Jiangsu Shuangle Chemical Pigment Co Ltd and Chongqing Jiangnan Chemical Co Ltd.

5) Cadmium pigments

Cadmium pigments are a type of inorganic pigments mainly composed of CdS. They have a very broad color spectrum, ranging from light yellow to orange red and red until garnet. There are many types of cadmium pigments, such as cadmium yellow, cadmium orange and cadmium red. Cadmium pigments have a bright color, excellent resistance to light, sunning, weather and high temperature, and high hiding power and tinting strength.
   Due to their high toxicity, cadmium pigments have been basically eliminated in China. But because of their excellent durability, they still have some industrial applications. In 2010, the combined output of cadmium pigments was about 20 000 tons, and their production capacity was about 50 000 t/a in China.

6) Mixed metal oxides (MMO) pigments

Mixed metal oxide (MMO) pigments are new-type, high-performance, eco-friendly and non-toxic inorganic pigments made with a variety of metal oxides by solid state reaction at high temperature.
   Due to their non-toxicity and high performance, MMO pigments have begun to attract attention from the architectural coatings industry and to get wide applications. In recent years, the global demand for MMO pigments has grown fast. In 2005, it was about 50 000 tons. But in 2011, it may soar to 300 000 tons.
   In Chi