A decal consists of several layers of materials. A bottom layer of backing paper with its glue-like substance, an intermediate layer of printed colours and a top layer of lacquer coating (cover coat ). The backing paper is porous so it will absorb water. This softens the glue and releases the printing (which is held intact by the top coating). This allows the design to be transferred from the paper on which it was printed to the surface being decorated.
Special inks are used which can withstand the high firing temperatures. CERAMIC DECALS, GLASS DECALS and NON FIRE DECALS are made with different inks.
Decals can be applied to any solid sealed surface.
CERAMIC DECALS are usually applied on fired glazed finishes. Most of these surfaces are white, ivory, or pastel colours. Most are not opaque enough to provide good results against dark backgrounds.
GLASS DECALS may be applied to transparent or opaque glass surfaces. These are stronger in colour and may be used on dark backgrounds.
NON FIRE DECALS can be used unfired on any sealed surface. Eg. Candles, soap, terracotta pots, milk churns, watering cans, woodwork, guitars, pianos, furniture restoration etc