What are the basic characteristics of the gel coat

Gel coat is a thin, spraying or brushing the mold surface of the colored resin. This layer of gel coat protects the mold and the final product, to avoid all kinds of physical and chemical impact. It enables easier demolding products, fiberglass chopped strand mat and improve the appearance quality of the products.

Unsaturated polyester resin (UP) used in gel coat is mainly based on isophthalic (ISO), and usually combined with neopentylglycol (NPG). Others gel coat is based on a vinyl ester resin, when you need a better chemical resistance, this kind of gel coat would be the best choice.

It’s not same to resin, gel coats also contain inert mineral fillers, anti-sag additives (such as silica and pigments, thixotropic agents, etc.), stability-enhancing additives and promote the curing accelerator.

Gel coat mainly as a protective layer for the reinforced unsaturated polyester, which is used in shipbuilding and transportation, cast polymer, bathtub, shower and swimming pool.