| A good many of historic stones exposed out-of-doors are badly damaged due to natural and human factors. Their weathering state is badly serious. If people should not take effective measures to minimize damage from circumstances and slow down the ageing process of stones, a lot of historical value of historic stones will be fading away. However, hardly any protective materials do meet with all requirements now. Consequently, it is a very urgent task to explore new protective materials with a good performance which are fit for historic stones.In this paper, a review of the historic stone weathering and protective materials is summarized and the following results have been obtained by investigating:(1) Latex resin has gradually used in the protection of historic stones, because of its low toxicity and rare pollution. According to the tests of water resistance and invariability, a choice was made in the four latex resins of acrylate resin latex, organosilicone acrylate latex, polyurethane latex and epoxy resin latex. The tests indicated that epoxy resin latex had excellent capabilities in hydrophobicity and invariability, and could hold back the destroy from water and salt.(2) Nano-material, which was widely used now, was selected as surface protectant. In this work, epoxy resin latex was taken for base, silica sol and the other assistants for assessories, confected a complex material which could not only prevent historic stones from weathering but also make rarely hazards to the environment. The main properties of the composite protective coating were tested by using measure of angle of contact; Ultraviolet Spectroscopy etc. the composite protective coating performed well in many properties, such as ultraviolet shield, consolidation, invariability, ageing resistance and recoatability. The composite protective coating was not innoxious but also colorless, transparent and nonluminous. It was effectively used for the protection of historic stones.
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