| Pearlescent pigment has characteristics of florid pearl luster and bright pearl. It can be used in dope, ink printing, decorativeness, cosmetic, rubber and leather as a addition agent. The preparation method of pearlescent pigments was based on the liquid phase technique, which had the disadvantages of long hydrolyze cycle, large energy expending and plentiful sewage letting. With industry developing, The pigments with superior performance and more colorful are needed. Furthermore, the preparation of pearlescent pigments have a trend from one-coated layer to multi-coated layer. However, the liquid phase preparation method cannot control colour changing accurately, so it was very difficulty in exploiting new products.Metal Organic Chemical Vapour Deposition (MOCVD) technique is an effective method for acquiring special function materials and membrane including superconductor in high temperature and semiconductors. It is based on the deposition of oxide thin membranes or metal thin membranes on the substrates with the gas phase reactions. This technique is also an important method of synthesizing solid materials that have potential applications in industrial field. On the other hand, spout-fluid bed technique can fluidize super-small particulates, obtain heat transfer and mass transfer with high efficiency, and give shape to speediness surface reaction. In the present work, the MOCVD technique coupled with spout-fluid bed technique was successfully applied to preparation of one-coated and two-coated mica pearlescent pigment. The proposed method has the advantages of short reaction cycle, small energy expending and no environmental problems. It is a green chemical technique and gives a new industry route for exploiting multi-coated pearl pigment.The main points of this paper are as follows:1. Iron oxide-mica pearlescent pigment was prepared by Fe(CO)5 in a spout-fluidized bed using MOCVD technique. The pigments' capability was measured by X-ray Debey Powder Diffraction, Scanning Electron Microscope (SEM), Electron Microprobe and Chromatism Apparatus. It is proved thatbrown pearlescent pigment can be prepared at 250℃ in oxygen flow of 3 ml-s"' and deposition time of 5 minutes. At higher temperature and longer deposition time, red-brown, golden-red and orange-red pigments were investigated too.2. The microstructure and optical properties of pigments were also investigated. The results showed that the uniform diameter watermill mica was the best material for pearl pigment. The pigment prepared by the present MOCVD method is a nanometer oxide particle which refraction index is higher than mica. A distribute equably and structure compactly thin films was obtained.3. The MOCVD procedures with tetrabutyl titanate (Ti(OC4H9)4) carried by pure nitrogen were employed under various conditions. Anatase TiO2 was obtained at 300℃. Denser coated rutile TiO2 on mica can be prepared at 500℃. When plenty oxygen was present, more uniform and denser coat could be obtained.4. Iron oxide film coated on TiO2 has been successfully carried out. The results showed that two-coated mica pearlescent pigment has higher luminance, more plentiful color, mellower colour and more weather resistance than one-coated pigment.5. Based on investigation of convective heat and mass transfer of spout-fluidized bed, the thermodynamics and kinetics of Fe(CO)5 and Ti(OC4H9)4 was calculated.6. According to standard (GB), pigments were successfully applied to car paint, plastic, cosmetic and wall paint.
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