Industrial Heating and Drying with Silar® Microwave Absorbent Ceramics
Industrial microwave drying and heating is well established, but has limitations. Silar® Microwave Absorbent Ceramics overcome these limitations, making microwave processing more versatile.
Silar® Microwave Heating Elements help dry and cure substrates like paper, textiles, and nonwovens when incorported in microwave oven design. They also cure water-based inks, latex coatings, and polymers. Many coatings must heat to 120°C to 150°C to cure. Using Silar® elements at the end of a microwave chamber with appropriate wave guide equipment can produce a terminal curing stage at the oven outlet. The result is cost-effective microwave drying and curing with higher speeds, efficiencies and uptime than conventional ovens.
Silar® Elements heat quickly allowing instantaneous starting and stopping, giving printers and converters more uptime and higher yields. Note how Silar® element temperatures rise over time:
Silar® Microwave Heating Elements offer many advantages:
- Location: They can be placed anywhere in the oven, and very close to target substrates
- Instant heat: From room temperature, Silar® rods come up to service temperature in seconds
- Constant heating rate: No change in dielectric loss tangent from room temperature to 1000°C
- Bone dry capabilities: Substrates can easily be moved into a bone dry state when microwave radiation is coupled with Silar® elements
- Elevated temperature heating and curing: Once water is evaporated, Silar® rods are there to drive temperatures up to cure or set inks, coatings and resins.
Silar® materials can be used to create virtually any type of microwave absorbent oven furniture desired. Because Silar® is a high temperature material, furniture can be used even for microwave melting of virtually any material, including metals. The diagram below shows a melting apparatus using Silar®:
Silar® materials offer advantages for microwave melting of materials:
- Rapid temperature rise: 1200°C per minute is easily attainable
- Chemically inert and stable: Silar® is exceptionally stable - it won't react with anything
- No arcing or sparking: Silar® will not arc or spark in a microwave field
- Functional at all frequencies: Silar® will heat equally well at 915 MHz and 2450 MHz
- No acceleration times: Silar® provides instant heat from ambient to service temperature
- No runaway heat: Unlike other materials, Silar® absorbs consistently and evenly across all temperature ranges, eliminating “runaway heat” caused by increasing dielectric loss tangent as temperature increases.
To see how Silar® elements can be used in Food Processing, Cooking and Cookware, click here.