CHEMICALS & CONFORMAL COATINGS
Below are representative lists of chemicals and materials to be used or avoided in LED manufacturing activities. For a complete and current
list of recommended chemicals, conformal coatings and harmful chemicals consult Cree LED’s
Chemical Compatibility Application Note
.
The video at
www.youtube.com/watch?v=t24bf9D_1SA
illustrates the process Cree LED has developed for testing the compatibility of
chemicals and materials with LEDs. You should also consult your regional Cree LED Field Applications Engineer.
Recommended Chemicals
In testing, Cree LED has found the following chemicals to be safe to use with XLamp ML family LEDs.
•
Water
•
Isopropyl alcohol (IPA)
Chemicals Tested as Harmful
In general, subject to the specifics in Cree LED’s
Chemical Compatibility Application Note
, Cree LED has found certain chemicals to be
harmful to XLamp ML Family LEDs. Cree LED recommends not using these chemicals anywhere in an LED system containing XLamp ML
Family LEDs. The fumes from even small amounts of the chemicals may damage the LEDs.
•
Chemicals that might outgas aromatic hydrocarbons (e.g., toluene, benzene, xylene)
•
Methyl acetate or ethyl acetate (i.e., nail polish remover)
•
Cyanoacrylates (i.e., “Superglue”)
•
Glycol ethers (including Radio Shack
®
Precision Electronics Cleaner - dipropylene glycol monomethyl ether)
•
Formaldehyde or butadiene (including Ashland
®
PLIOBOND
®
adhesive)
Hermetically Sealing Luminaires
For proper LED operation and to avoid potential lumen depreciation and/or color shift, LEDs of all types must operate in an environment
that contains oxygen. Simply allowing the LEDs to ventilate to air is sufficient; no extraordinary measures are required. Hermetically
sealing LEDs in an enclosed space is not recommended.
Potential of Silver Tarnishing
XLamp ML Family LEDs contain silver-plated parts that may tarnish (turn black) over time when exposed to oxidizing substances such as
sulfur, chlorine, or other halides. Oxidation of the leads can reduce the ability to make a good solder connection and affect the light output
of the LED. Exposure to oxidizing substances can come from materials used near the LED during manufacturing or from the air around
the LEDs during storage.
To reduce the potential of tarnishing for XLamp ML Family LEDs, Cree LED recommends that customers minimize exposure of the LEDs
to oxidizing substances at all times, including storage, manufacturing and product testing. Potential sources of oxidizing substances
include paper, air filters, some cleaning chemicals, cardboard boxes and rubber anti-static mats.
XLAMP
®
ML FAMILY LED SOLDERING & HANDLING
© 2010-2021 Cree LED. The information in this document is subject to change without notice. Cree
®
and the Cree logo are registered trademarks, and
the Cree LED logo is a trademark, of Wolfspeed, Inc. XLamp
®
is a registered trademark of Cree LED. Other trademarks, product and company names
are the property of their respective owners and do not imply specific product and/or vendor endorsement, sponsorship or association. This document
is provided for informational purposes only and is not a warranty or a specification. For product specifications, please see the data sheets available
at www.cree-led.com.
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