Do you want to learn more about UV, IR and flash technology? Get inspired by the answers we give to the frequent questions people have.
- How wide should the heated length of the infrared system be compared to the material width?
- Is infrared radiation dangerous?
- Is it possible to control the maximum temperature?
- What input power will be required?
- What is the lifetime of an Infrared emitter?
- What is the optimal distance between the infrared emitters and the product surface?
- What is the optimal Infrared radiation or wavelength for my application?
- What is infrared radiation?
- Can infrared emitters be regulated and, if so, how?
There are several factors such as the distance of the infrared system to the heated material and the temperature. We are able to calcutate this data based on our experience and provide you with a complete solution.
No, not in principle. IR radiation is pure heat. Only after too long or too strong radiation overheating could occur and so cause damages.
Yes, and we are able to deliver control units and power supplies together with the Infrared system.
This depends on the absorption characteristics of your material, its specific heat capacity, its mass, the temperature required and the speed of your process.
The life time depends on the type of the Infrared emitter and on the ambient conditions - it is between 5.000 and 30.000 hours.
The quality of the material and other parameters influence this distance.
Optimal parameters can be worked out by tests in our application centre or from experiences in earlier applications.
In general the heating of uncoated metals favours the shorter wavelengths.
For coated metals and other non-metal heating applications medium wave and carbon medium wave are the most energy efficient.
The sun sends IR radiation to the earth, similar to an IR emitter which sends radiation to the product, without any contact or transfer medium. Unlike the sun, an IR emitter can be switched on and off whenever it is needed.
Yes, infrared emitters can be regulated, but with different response time. Short wave, fast medium wave, and carbon emitters react within 1 sec. The classic medium wave emitter within 90 sec. Gas catalytic emitters can be regulated steplessly from 20% to 100% power during operation.
- Which gases are needed for a gascatalytic oven?
- Will a gascatalytic oven set free dangerous gases?
- What ist he difference between gas infrared and gascatalytical infrared emitters?
- Is there an open flame during the gascatalytical infrared reaction?
Mostly natural gas, but propane is also possible.
No, the gascatalytic reaction will set water and CO2 free. There is no NOx!
Conventional gas infrared ovens burn gas and heat up materials like metal or ceramics which then transfer infrared radiation. Gascatalytical infrared is a chemical reaction, which transfers gas with the help of a catalyst into water and carbon dioxide. This reaction sets infrared heat free which can be used.
No, there is no flame, as it is a simple chemical reaction which produces heat.
UV and UV LED
- Do frequent on/off cycles affect UV LED lamp life? What about dimming?
- Can I combine my existing arc lamps with UV LED, i.e. use the arc lamps after the UV LED to get surface cure? Are there other ways to improve surface cure with UV LEDs?
- If UV LED doesn’t emit IR energy like traditional UV curing does, how does this affect the UV LED formulations?
- If I'm using long wavelength (iron, metal halide) arc lamps, can I use UV LEDs with my existing UV chemistry?
- How much less heat does the UV LED deliver to the ink / coating / substrate? What kinds of materials are now possible?
- Will the UV LED energy penetrate opaque surfaces such as paper?
- What type of cooling is used for the UV LED's? Heatsinking? Air cooling?
- How does adhesive strength and reliability of UV LED curing compare to conventional IR cure adhesive applications?
- What is the recommended [energy output] calibration cycle for the UV LED system? Can this easily be done by oneself?
- Can you make non yellowing UV LED coatings?
No, it does not affect the UV LED lamp life. Dimming has no effect on the life.
Absolutely you can use existing medium pressure mercury (MP) lamps – both arc and microwave – to achieve surface cure after UV LED exposure. We have also seen applications where amalgam (low pressure mercury lamps) that only emit at 254nm are used to enhance surface cure.
Nitrogen inerting is another option – reduces oxygen inhibition which hinders surface cure. Also some formulating options depending on your specific application and requirements that may improve surface cure results.
Many UV curable formulations, for example electronic potting compounds and other applications benefit from the IR heat traditional UV arc and microwave-powered systems provide because it helps speed the kinetics of the chemical reaction. So yes, formulators have to consider this when formulating for UV LED, because there is not this IR component.
Metal halide lamps emit much of their UV energy in the UVA band – which is where the current UV LEDs emit. So, UV LED has a high probability of success. However, many photoinitiators still need energy from the UVB and/or UVC band to create the free radicals efficiently.
Almost all formulations have to be formulated specifically for UV LED curing for optimal properties and process speeds.
This is a blanket statement used by the industry because approximately 30 – 40% of the energy emitted by a medium pressure lamp is IR in addition to the visible light.
So, both visible and IR energy is not getting to the substrate/target, inherently making UV LED curing technology a cooler process. As far as specific materials, it depends on the material’s distance from the UV LED unit, absorptivity and other factors, but heat sensitive plastic films, sensitive electronic and medical components are some examples of materials that can be cured using UV LED.
Depends what is meant by opaque. Very very little energy would penetrate paper.
Both air and liquid cooled UV LEDs are commercial and in use. In fact, the very first UV LEDs were all water-cooled. At this time, air cooled UV LEDs systems dominate the market. Having an air cooled system installed is a more straight forward installation, less external equipment, less space.
UV adhesives cure immediately or much quicker than IR adhesives.
Of course it depends on the specific formulations you are comparing and there's no reason UV LED adhesives would be less reliable or provide lower adhesive strength assuming they are properly cured.
UV output should be measured using a UV LED specific radiometer that's properly calibrated. It depends on your specific process, but most users find weekly or monthly readings are adequate.
Yes, you can easily take these radiometry readings yourself.
It is a challanging application for UV LED because we are working with a longer wavelength where many photoinitiators have some yellowing characteristic. You require careful selection of the photoinitioator, maybe in combination with another photoinitiator.
To reduce yellowing further, you may need to reduce the photoinitiator concentration in the formulation, which may mean a lower cure speed. The photoinitator companies are working on less yellowing photoinitiators for the current UV LED wavelengths.