IR Curing Sources
Today, many companies use infrared (IR) ovens because of their fast pace, small floor space, and other benefits. In some applications, IR systems can cure powder coatings in as little as 30 seconds! To further understand the IR curing process, here is a look at the three types of energy used during the process:
- Reflected Energy: The energy in the system that bounces back.
- Absorbed Energy: The energy absorbed by the coating (usually by the pigment).
- Transmitted Energy: The energy that passes through the film where the modified material either absorbs or reflects energy.
When a company chooses to use IR ovens, they are also given several options of specific wavelengths. These three wavelengths are chosen based on certain trade-offs of the emitter. Below is a list of several wavelength properties to consider:
- Short Wave: A 0.76 to 2.3 micron wavelength with a source temperature of 2000° to 5000° F.
- Medium Wave: A 2.3 to 3.3 micron wavelength with a source temperature of 860° to 2000° F.
- Long Wave: A 3.3 to 1,000 micron wavelength with a source temperature of 100° to 860° F.
In addition, organic coatings with C-H (Carbon-Hydrogen) and O-H (Hydrogen) bonds have a peak absorption in the 2.2 to 3.3 micron wavelength range. The peak absorption is categorized by intensity and frequency.