non yellowing epoxy resin

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#1

I’m looking for a laminating epoxy resin that is crystal clear and won’t yellow. I plan on clear coating the finished parts with automotive 2k clear coat.

The customer doesn’t want any yellowing. Got any ideas for a product?

I was thinking of Resin Services HTR212-386.

We are going to cure the parts in an oven at 200F but i’m hoping i can get a tg
of 300F.

#2

For the epoxies that tended to get yellow I used black tinting.Hope this helps

#3

How many drops of black dye per ounce of epoxy?

note: i sometimes use base coat clear ( intercoat clear ) and mix in a little black basecoat paint so it is just tinted black somewhat but transparent. Then spray the finished part… let it dry for 30 minutes, then spray on your clear coat paint. If there is very tiny air trapped in the part surface it helps hide it and carbon still shows and looks good. So i am guessing this is how you tint the epoxy… just make it transparent black?

#4

Just a few drops will do it for tinting the resin black (not trasparent black), since via vacuum the resin will just get the fabric wet and discarded.

#5

I’ve been dying my resin black for years now. Just remember… a little bit of dye goes a looooooong way. I usually just dip the tip of the mixing stick into the dye and mix away.

#6

question, does epoxy still turn yellow when it’s been clear coated? I was under the impression that clear coating prevented UV damage which is what leads to discoloration… Am I missing something? thanks.

#7

I ordered some epoxy resin from ResinServices.com today. It’s HTR212-386… 386 being the clear hardener. They claim a room temp cure, without post cure will yield a tg of 375F. post curing in an oven is good too and you can get it up to 450 tg i believe. For our planned part we only need 300F. It is crystal clear when mixed. Same resin Rousch Racing uses for their carbon parts. I know… who cares who uses it… but it does make me feel better knowing a well known american company uses it. ( america vs. china) Many people complain about clear cf parts turning yellow, which of course is what you get for a $700 hood.