Initial heating of the phenol and formaldehyde (in the presence of an acid or base to get the reaction going) produced a shellac-like liquid good for coating surfaces like a varnish.
开始加热，酚和甲醛(需有酸或碱促使其反应进行)便产生了像紫胶样的液体，能像清漆一样涂于物体表面。
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Features: This product protected with sealed finish to resist paint from acid rain, sunlight fading, UV oxidation, high temperature, shellac, sap and polished scratches and other effects;