As industrial activities develop, acidic materials are concentrating in the air, resulting in the dangerous pollution of acid rain. Such rain will significantly damage ancient stone architecture, because stones consist mainly of calcium carbonate, which is easily eroded by acid rain.
Currently, we are covering ancient architecture buildings with a thick layer of paint, which protects the architecture from water. But this method has a negative side-effect: it is not good for the thermal expansion and contraction of the outer walls.
After many trials, scientists found that vegetable oil can make better outer-wall paint than animal oil. Mixed with certain additives, vegetable oil-based paint can create a thin layer of protection on the outer walls of ancient architecture, without compromising the original structures and outer walls of the buildings. Such paint has good permeability, which means it can fix the original defects and cracks and reinforce the architecture.
The final product of vegetable oil-based paint is a transparent fluid that solidifies soon after it is applied on the walls, and then forms a super-thin protection layer with the thickness of only dozens of nanometers. The shield of the solidified paint is strong and flexible like rubber, and it will not affect the thermal expansion and contraction of the stones in the outer walls. In addition, this shield is transparent. You cannot see it with your eyes or feel it with your hands, and it is as if the outer walls never changed.
