1： Classification of yacht paints according to yacht materials

Yachts can be divided into wooden boats, fiberglass boats, Kevlar fiber reinforced composite boats, steel boats and aluminum alloy yachts. At present, GRP boats account for a large proportion, and Kevlar reinforcement materials are widely used in rowing, sailing and luxury boats; Aluminum alloy yachts account for a certain proportion in outboard motor boats and large luxury yachts; Steel boats account for a large proportion of large luxury ocean yachts over 35 meters. The types of paints used are different according to the materials, and they are mainly divided into four categories: wood yacht paint, glass fiber reinforced plastic yacht paint, steel yacht paint and aluminum alloy yacht paint.

2： Difference between yacht paint and ordinary paint:

1. In general, yachts pay more attention to beauty than ordinary ships in appearance, so the requirements for paint glossiness will be higher.

2. The yacht is exposed to the sun for a long time, so the UV resistance of the yacht paint must be better than that of the ordinary paint. No chalking, no yellowing and no fading after long-term exposure.

3. The sea water resistance of yacht paint is better than that of ordinary paint, and it will not fall off after long-term immersion.

3： Matching of yacht paint:

1. The matching of wooden yacht paint mainly includes: first, scraping and painting putty or putty, filling gaps, and leveling pits. The second coat is sealer (polyester sealer or acrylic sealer). The third layer is polyester paint, polyurethane paint, acrylic paint or nitrocellulose paint. The fourth layer is varnish (it can also be omitted).

2. Matching of GRP yacht paint: select paint types according to the material of GRP, mainly including three types: HJ104 epoxy thick coat finish, HJ571 acrylic finish or HJ500 aliphatic polyurethane finish. Generally, only one or two finishing coats are applied, and no primer is applied.

3. The steel yacht paint is matched with HJ103 epoxy micaceous iron oxide thick coat primer (two coats) and HJ500 aliphatic polyurethane finish (two coats).

4. Supporting aluminum alloy yacht paint is: the first coat, HJ126 epoxy zinc yellow thick coat primer (or phosphating primer). Second, scrape and coat the putty. The third layer is HJ499 polyurethane intermediate paint. The fourth layer is HJ500 aliphatic polyurethane finish (2 layers).

4、 Construction method of yacht paint:

Mainly introduce the construction process of aluminum alloy yacht paint:

A. Surface treatment: aluminum is a very characteristic metal. When it is oxidized by air, a layer of dense alumina is formed on the surface. This film has excellent corrosion resistance. It is completely unlike steel, which can be corroded all the time. Therefore, the paint on the aluminum alloy is only for decoration. But ordinary paint is difficult to adhere to aluminum alloy. The aluminum alloy surface must be treated before painting.

There are several main methods for aluminum alloy surface treatment: the first is to change the properties of aluminum alloy surface, and the aluminum alloy can be treated with phosphating solution or phosphating primer. After reacting with the aluminum alloy, an aluminum phosphide film easy to adhere to paint is formed. Later, the paint can be sprayed easily. The second is to use a special primer for aluminum alloy, such as Haijian epoxy zinc yellow thick coat primer, Shanghai International epoxy zinc yellow primer, etc., and then use a two-component polyurethane paint.

B. Painting process:

1. Construction environment: the coating environment temperature is 5-35 ℃, the relative humidity is below 85%, the substrate surface temperature is more than 3 ℃ above the dew point, and the temperature and humidity should be measured near the substrate. The substrate temperature is higher than 40 ℃, so construction is not recommended. The coating shall not be carried out until the coating conditions are met.

2. Surface treatment: firstly, use lye and diluent to remove dirt such as oil stain attached to the surface of aluminum alloy or stainless steel. Use power tools or sand blasting method to remove the surface oxide layer to expose the metal color, luster and certain roughness. The treated surface is free of dust, oil, moisture and other contaminants. After the surface treatment meets the requirements of painting, the first primer must be applied within 4 hours.

3. Paint preparation. Special diluent can be added properly (do not add epoxy diluent to aliphatic polyurethane finish paint), the amount depends on the situation, and the general dilution is 5-10%. It shall be noted that each time the paint is prepared, it shall be prepared and used according to the dosage of the day to avoid waste.

4. Manual roll coating or brush coating, airless spraying and other construction methods shall be adopted. The coating interval: about 12 hours (23 ℃) after the first epoxy zinc yellow thick coat primer is completed, i.e., it is dry, and then the putty shall be applied continuously. After the putty is dry and dust removal is polished, the intermediate paint can be applied continuously. At 23 ℃, about 12 hours later, the aliphatic polyurethane finish can be applied continuously. When the temperature is high, the coating interval can be shortened appropriately.

5. After the construction of each coating, there shall be no obvious sagging, pinhole, shrinkage, orange peel and other phenomena on the surface. The longest construction interval between two coats of paint should not exceed 15 days. Before the next coat of paint, check the paint film for dust, oil, etc. The parts with local missing coating and insufficient film thickness shall be repaired.