The article deals with the preparation of artificial copper pigment based on brochantite. The pigment was prepared by slow additions of sodium hydroxide solution into the solution of copper sulphate. The studied parameters were addition rate, solutions concentrations, ferrous ion addition, and filtration time. The prepared pigments were evaluated by means of X-ray diffraction and spectrophotometry. Subsequent pigment immobilization in an acrylate varnish was also studied. Observed parameters were influenced by solvent type, mechanical or chemical dispersion, and natural aging in an aggressive outdoor atmosphere. Pigment containing varnishes were evaluated by means of spectrophotometry, optical profilometers, and pull-off test. Slow hydroxide addition allows the formation of brochantite pigment. Fast filtration limits backward pigment decomposition. Ferrous ion improves pigment color closer to natural copper patina. The ideal immobilization procedure includes ethylacetate as a solvent and mechanical dispersion. The varnish filled with pigment provides sufficient adhesion to the metallic copper substrate as well as long-term color stability in the outdoor atmosphere.

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基于褐铁矿的颜料生产的新方法及其用于修复历史铜制物体的固定方法

本文探讨了基于褐铁矿的人造铜颜料的制备。通过将氢氧化钠溶液缓慢添加到硫酸铜溶液中来制备颜料。研究的参数为添加速率，溶液浓度，亚铁离子添加和过滤时间。通过X射线衍射和分光光度法评价制备的颜料。还研究了随后在丙烯酸酯清漆中的颜料固定化。观察到的参数受溶剂类型，机械或化学分散性以及在侵蚀性室外气氛中的自然老化的影响。通过分光光度法，光学轮廓仪和剥离试验评估含有清漆的颜料。缓慢添加氢氧化物可形成溴锌矿颜料。快速过滤可限制颜料向后分解。亚铁离子使颜料的颜色更接近天然铜绿。理想的固定程序包括乙酸乙酯作为溶剂和机械分散体。填充有颜料的清漆对金属铜基材具有足够的附着力，并在室外大气中具有长期的颜色稳定性。