Zinc spray paint an artifact is no simple task because the zinc coating has a porosity of 8-10%. To fill the porosity apply sealants which have the following advantages:

penetrate into the pores and reduce the area of ​​the coating exposed, slowing down the rate of dissolution, pave surfaces, preventing the retention of dirt and other pollutants. The coating remains clean, aesthetically pleasing; can be moved easily and can be pigmented to give a color most attractive.

A sealed surface does not need painting.

Sealants must have low viscosity (3 < poise), average power Feuillant, low absorption of water and inert to chemical attack.

Should be applied immediately after the spraying of zinc to prevent contamination.

Often apply a primer polyvinyl before painting or alternatively a phenolic resin, or with vinyl polymers, phenol epoxy.

There is a difference between sealants and coatings.

The paint is superimposed on the metal surface while the sealant is low stickiness and penetrates into the pores and seal them without adding thickness to the coating.

Before painting a manufactured galvanized spray is recommended to apply a sealant, because without it many of the paint binders remain in the pores of the coating pigments leaving scattered (untied) on the surface. You have to choose the paint is compatible to avoid reactions with zinc, wrong because the paint could form compounds with zinc interface that can impair their anchorage.

We must avoid the alkali.