Importance of paint on ships

The painting of a boat when it is in the dry dock does not only have a decorative function. It is necessary for the protection of the boat and to extend its life. In addition, before applying the boat hull paint, it is essential to carry out a priming process, which protects it better than the usual paint, which will determine the colour.

Why is it necessary to paint ships?

Periodically carrying out the process of priming and painting the boat is not only advantageous, but necessary. The process has these functions:

• It makes the boat easier to clean and safer to navigate.
• It creates a film between the surface of the hull and the environment, protecting it.
• Anti-corrosion boat paint protects metal hulls against corrosion.
• Prevents osmosis.
• Prevents wood from rotting and drying out.
• It prevents encrustation of underwater areas, which can slow the ship’s progress and damage the hull.

Classification of paint types

The boat is always painted with several coats of different types of paint, which must be applied in the correct order. These are listed below, starting from the innermost layer of paint to the outermost.

Primer

The primer or sealer is the first product to be applied after cleaning. Its function is to protect the hull and serves as a base for the other coats of paint. It also prevents water damage to fibreglass and wooden hulls. In the case of metal hulls, it protects them from corrosion.

Nautical primers can be divided into two types:

• One-component: Synthetic and ready to use, but somewhat less durable.
• Two-component, such as polyurethane or epoxy primers. Epoxy is made from resins and sold in two parts: base and catalyst. These coatings have higher resistance.

Currently, epoxy is one of the most widely used primers, due to its high resistance.

Intermediate layers

The hull is divided into different zones:

• Hull or hull skin: Part immersed in the water.
• Topside: Above the waterline, resistant to weather but exposed to the sun.
• Engines: Require specific coatings.

Antifouling or patent paint is used on the hull to prevent fouling. On the topsides, enamel or primer is used. Engine covers may require varnish or sunscreens. Outboard engines use antifouling; inboards need engine-specific enamel.

Finishing paint

Teak decks should be protected with teak oil every 3–4 months to prevent greying. Gel-coat decks should use enamel with anti-skid additive.

One- and two-component paint

One-component paints like enamel or polyurethane are traditional and easy to apply but can be soft. Two-component polyurethane is more wear-resistant, longer-lasting, but more expensive and harder to apply.

Two-component paints cannot be applied over one-component paints due to solvent incompatibility.

Paint according to the resin

Paints can be based on different resins: oil, polyester, acrylic, vinyl, epoxy, polyurethane, alkyd, silicone, silicate, rubber, etc. Each type has unique properties. For example, silicate paints resist high temperatures, while silicone paints are water-repellent.

Factors for better paint performance

How often a boat needs to be painted depends on:

• Material and condition of the boat.
• Environmental conditions (temperature, humidity).
• Type and quality of paint.
• Combination of paints used.
• Weather during application, skill of painters, and drying conditions.

At Suisca Group we offer a primer and paint service for boat hulls. With more than 30 years of experience in the maritime sector, we deliver top quality to ensure your boat’s paint lasts as long as possible. Leave your vessel in expert hands!