Gel coat resin is a surface coating that gives the composite material a beautiful appearance, resistant to chemical attack, scratches and aging, etc. It protects it. Therefore, the selection of high-quality gel coat resin and the correct application process are critical. Because gel coat resins make products with high gloss, good weather resistance and wear resistance, and have different properties and excellent manufacturability, it naturally becomes the first choice of gel coat resins for many FRP manufacturers. In the color gel coat resin formulation, a special unsaturated resin is selected as the matrix. High-quality imported color paste and imported additives such as aging resistance, easy defoaming and high thixotropy are adopted. Therefore, the gel coat resin exhibits high surface gloss, high surface hardness, high strength and durability.
In order to ensure a satisfactory FRP product and get the best appearance, the mold must be fully treated in advance, and the operation of the gel coat resin must be correct. This is very important, and it is also very necessary for the training industry of the operator. When using gel coat resin, whether it is spray or hand brush, the application process is as follows:
1. Choose a suitable gel coat resin type before use.
2. Prepare the mold thoroughly and handle the mold surface before use.
3. Fully stir the gel coat resin in the original barrel before use, but the speed should be appropriate to avoid mixing bubbles.
4. Before starting construction, it is recommended that the working temperature of the gel coat resin and the mold is 15℃-30℃. The ideal mold temperature should be 2℃-3℃ higher than the gel coat resin temperature. In this way, a more lustrous and plump gel coat resin surface is obtained after curing.
5. The relative temperature in the workshop should be lower than 80%. If the humidity is high, the curing temperature should be increased. In addition, water should be prevented from collecting on the mold surface.
6. The mold surface needs to be carefully polished and waxed sufficiently, and the new mold should be pretreated. Do not use silicone-containing release wax. Use water-soluble mold release agent must wait for its moisture to evaporate before spraying Futian gelcoat resin.
7. When using gel coat resin, do not add solvent to dilute it, such as acetone, banana water, etc. If a lower viscosity is required during use, a small amount of styrene (≤2%) can be added.
8. The curing agent used for the gel coat resin is methyl ethyl ketone peroxide, and the dosage is generally 1-2%. If the amount of the curing agent is too high or too low, it will affect its curing degree, which will make the water resistance and weather resistance of the gel coat resin. Sexuality is reduced.
9. If you add color paste, you must ensure the uniformity and stability of the color. Weigh accurately according to the recommended amount, use low-shear equipment to stir, or use color gel coat resin.
10. When spraying, in order to achieve an appropriate thickness, spray 2-3 times, so as to obtain a good defoaming effect.
11. When spraying Futian color gel coat resin, select the proper nozzle, spray pressure and spray distance (50-80cm) and vertical direction. The spray gun should move at a uniform speed. The nozzle should be moved out of the mold first, and then from the edge of the mold Stop outside, colleagues should make sure the air source is dry and clean.
12. In order to obtain a smooth gel coat resin layer, the spray thickness is 0.4-0.6 mm (equivalent to 500-700 grams per square meter gel coat resin), the thickness is too thin, causing under-curing: too thick, easy to sag, crack and Pinhole. The thickness can be measured using a thickness gauge.
13. For difficult parts of the mold, such as deep grooves, when the spray gun cannot maintain a reasonable position, you must use a brush. The Jiaoning time in this area is longer, and a small amount of ventilation can be used.
14. Make sure that the mold has good ventilation, because the styrene monomer will play a role in polymerization inhibition, this is because the molecular weight of styrene is large, it will sink in the concave of the mold.
15. Once the gel coat resin is fully cured (the gel coat resin layer is only stuck to the hand with a finger and not attached to the hand), proceed to the next step.
Matters needing attention when using gel coat resin:
1. When storing gel coat resin, avoid direct sunlight, temperature ≤25℃, and store separately with methyl ethyl ketone peroxide.
2. The pretreatment mold and gel coat resin construction area should avoid the generation of dust. Gel coat resin should be poured into a clean bucket.
3. When mixing the curing agent or color paste, do not mix too much air.
4. Use high-shear mixing equipment. Otherwise, it will cause a decrease in the thixotropic index, separation/aggregation of color paste, flow glue and bubbles.
5. It is forbidden to pour the gel coat resin directly on the mold and brush directly.
6. Do not adjust the gel time too fast, which is not conducive to the escape of bubbles.
7. The amount of curing agent added should be appropriate, and the amount of curing agent can be checked by measuring the gel time.
8. Do not use silicone-containing mold release wax, they will produce fish eyes.
9. Use good quality, low water content, medium active oxygen content of methyl ethyl ketone peroxide, inferior curing agent will seriously affect the performance of the gel coat resin.
10. Do not add accelerators by yourself to the color gel coat resin to avoid affecting the color.
11. The best performance of the gel coat resin can only be fully reflected when it is fully cured, and qualified customers should post-cure the product.