As a new type of coating, powder coating is widely used because of its solvent-free, less pollution, and environmental protection characteristics. This article introduces the precautions in the formulation of powder coatings and a production process of powder coatings. In the formula of powder coatings, the function of the embossing agent is that it is added to the base powder of the special formula by dry mixing method, and the coating film is wrinkled or patterned through its flow, and some are called embossing agents or patterning agents. Commonly used embossing agents are acrylate homopolymers or copolymers, etc. Generally, epoxy resin or polyester resin is used as a carrier for dispersion, and the content of active ingredients is less than that of general leveling agents. In order to disperse evenly when the embossing agent is dry-mixed with the powder coating, the fineness of the pulverization requires a sieve of 140 mesh or more.
By adjusting the type or amount of each component in the powder coating formula, adjusting the melt level fluidity of the system, the type and amount of embossing agent, and the type and amount of additional pigments, patterns of different pattern sizes and colors can be obtained . Embossing agents can be used in epoxy, polyester epoxy, polyester and polyurethane powder coatings.
The following introduces the production process of a powder pattern coating - outdoor camel gray wrinkle powder coating:
1. Base powder formula
Sino-French P9336 Polyester | 52 |
TGIC curing agent | 4 |
Precipitated barium | 27.5 |
Titanium dioxide | 15 |
carbon black | 0.03 |
Medium Chrome Yellow | 1.5 |
Second, floating agent dry mixing method plus:
① Add 0.2g of embossing agent K30 to 100g of base powder and mix evenly before spraying, which can achieve uniform medium texture and strong three-dimensional effect. Can be used on hammer pattern wrinkles. Added to various powders, the amount added is 0.1-0.3%. Dark with medium white point. The market price in Hubei is 28 yuan/kg.
②Add 0.15g of embossing agent T33 to 100g of base powder and mix evenly before spraying, which can achieve uniform fine lines and strong three-dimensional effect, and can be used for hammer pattern wrinkles. Added to various powders, the amount added is 0.1-0.3%. Dark with medium white point.
3. Pay attention to the following items when using the floating agent:
① Polyester resin should be stable and not denatured with temperature, curing agent, storage time and other factors.
②The method of mixing the base powder, embossing agent and pigment, the mixing speed and time have a significant impact on the pattern of the coating film. Only by controlling the same process conditions for each batch of materials can a relatively similar coating film appearance be guaranteed.
③The thickness of the coating film has an impact on the size of the pattern. Small patterns can be sprayed with a thin film thickness, and large patterns can be sprayed thicker as much as possible, otherwise the coating film will easily leak and affect the effect of the pattern.
④ In dark powder, there will be translucent white spots on the surface of the coating film due to the embossing agent.
