Bonded Powder Coating Technology:
The New Name of Aesthetics and Durability on Surfaces
Powder coating technology is widely preferred around the world thanks to its eco-friendly nature and economic advantages. The absence of volatile organic compounds (VOC), high coating performance, and cost efficiency make it indispensable in many industries.
However, metallic pigments in particular can cause homogeneity issues when applied with the traditional dry-blend method. At this point, bonded powder coating technology offers an innovative solution to the industry.
Differences Between Dry-Blend and Bonded Methods
Dry-Blend Method
In this method, the powder coating base (resin, pigment, filler, etc.) is mechanically mixed with metallic pigments. It is a simple and low-cost method. However, it has disadvantages such as:
• Separation of pigments during application,
• Color and effect differences in repeated applications,
• Unsuitability for recycling.
Bonded Method
Bonded technology, on the other hand, is achieved by subjecting the formulated powder coating base to thermal processing and mechanical mixing with metallic pigments at a temperature depending on the resin type. This way, the pigments bond to the resin and move together with the powder. The advantages are:
• Uniform color and metallic effect on the surface,
• More stable electrostatic charging,
• High transfer efficiency,
• Consistent results in repeated applications,
• Suitability for recycling.
In short, the bonded method provides a far superior outcome compared to the traditional method in terms of both aesthetics and durability.
Key Parameters in the Bonded Process
A high-quality bonded process is possible not only with technical expertise but also with specialized equipment. The main parameters are:
• Temperature: To bond metallic pigments, the glass transition temperature (Tg) must be reached. This value varies depending on the resin used.
• Mixing Homogeneity: A homogeneous mixture must be achieved at a specific temperature and duration, ensuring that nearly all pigments are bonded.
• Humadity Control: Humadity can reduce process quality and may cause blocking of the product if not properly controlled during storage.
• Machine Parameters: Mixing force, speed, and cooling time must be optimally adjusted.
