| 摘要 |
PURPOSE:To obtain an excellent selective absorbind surface, by sticking the colloidal particles of the metal onto the surface of the metal to be treated, then coating the treating liquid dissolved the organic derivative, and subjecting to the thermal decomposition. CONSTITUTION:The metal to be treated such as the Al or its alloy, stainless steel, chromium or the like is immersed into the colloidal solution consisting of the hydroxide such as Fe, Co, Ni, Cu, the hydrated oxide and washed by water. The washed metal is then dried to form the colloidal particles onto the surface of the metal. The diameter of the colloidal particle is 0.05-0.5mu, and the amount of the attached colloidal particles is 0.00002-0.002mg/cm<2> respectively. And then the treating liquid obtained by dissolving the organic acid salt such as Cr, Mn, Fe, the chelate compound and one or more kinds of the mercaptide group in the organic solvent is coated on the colloidal particles. A thermal decomposition is given to the particles in a heating furnace after coating of the treating liquid. In such way, a selective absorbing surface having a comparatively large metal or metal oxide particles in its metal oxide layer can be obtained. The thickness is set to <=0.8mu for the stuck layer of both the metal colloidal particles and the metal oxide layers. |
