Archive through September 09, 2011

Archive of Older Topics Archive - Product Discussions #5
21

They do, generally. But there has been quite a bit of progress in epoxy technology in the last 7-10 years. I would agree that most epoxies do yellow under extended UV light exposure - but there are some resin systems (some 100% solids amines and some epoxy/polyester hybrids) that demonstrate on a fraction of the yellowing we encountered consistently 10-15+ years ago.

There is, for example, epoxy resin technology used in a large percentage of modern surfboard manufacturing (especially after the demise of the largest foam blank manufacturer, forcing new technology development to fill market need) - Surftech is probably the best known manufacturer, using an epoxy resin to saturate fiberglass over a molded (as opposed to cut/sanded) foam or other synthetic core. Many of the lower-cost boards are plain white (to reduce cost) - I’ve never seen one turn yellow, and they’re subjected to UV light every time they’re used.

I’ve also tested samples of a few epoxy floor coatings that have also been touted as having “reduced yellowing qualities”, running a UV light curing machine over them (from another technology) that would yellow a “normal” epoxy in minutes and been quite surprised - the yellowing was not completely eliminated but it was very subtle.

Part of the rise in floor coating technology (in regards to non or reduced-yellowing epoxies) is due to some reluctance to use polyurethanes as an alternative because of the isocyanate component. With proper controls iso-containing systems like polyurethane or the one really gaining ground, polyurea, are as safe as other coating systems, but many engineers and health officials see “isocyanate” and “have puppies”. It’s simply a lack of understanding, but the result has been progress in epoxy technology to fill those gaps (whether they’re valid or not) and new products that just are not the same “epoxy” we normally think of.

They are, however, not as prevalent in the Architectural market as in marine and manufacturing. That’s why I’d like to see case histories on West’s products. Since one of the sellers is about 4 blocks from me I may just go over and pick some up for a “marine environment architectural test” (My wife HATES the south side of our house - it gets sun but the neighbors can’t see it - perfect for test applications!)

With enough case history backup I may slip it into my otherwise WIC/MPI based wood finishing specs.

22

don’t forget about the chalking…

From Epoxy Paints 101:

“The disadvantages of epoxies are that they tend to be brittle, quickly yellow in sunlight (white becomes a creamy color, light blue becomes light green, etc.) and lose their shine in sunlight. The yellowing and loss of gloss (even chalking in some cases) is due to the affect of UV on ALL epoxies (some epoxies will yellow in days, others take weeks but they all do eventually).”

http://www.epoxyproducts.com/epoxypaint101.html

23

I just spent the better part of 90 minutes pouring through “Epoxy 101”. Hopefully what I found will prevent others from wasting their time.

“Epoxy 101” is a proprietary site put together by one man who does not manufacture epoxies (at least as far as I can tell). He owns a company that distributes several obscure brands.

It’s a large website that has pages and pages of “value base” epoxies (a term that scares me right off the bat!) apparently manufactured by small blenders (another tidbit I found) and distributed by the owner of Epoxy Paints 101.

It’s a sales site with difficult-to locate technical specifics. Read on, it gets even more tangled -

The MSDS’s I located did not disclose clearly the manufacturer; one notes that some components are not disclosed because they’re trade secrets.

That doesn’t fly on an MSDS, so either they’re unaware non-hazardous ingredients don’t need to be referenced or unaware that full disclosure of hazardous ingredients is required unless a specific waiver is obtained from the federal government for security reasons.

There’s limited information on the site, no matter how massive they try to make it - and oddly, if you email them they (right at the email link) notify you that contacting them means you agree to all their terms, conditions, safety info and several other conditions that are so restrictive I could never contact them.

I’ve never seen anything like it.

The products on the site are totally unfamiliar; personally I’ve spent the last 18 years with the bulk of my time dedicated to specification, tech support and/or inspection of industrial coatings, and not to blow my own horn…but I would have probably tripped over a gallon or two in that time!

The products listed on the site are not on the MPI approved products list or any of the popular manufacturer-listed master spec systems.

None of the manufacturers I could find buried in the content are Sherwin Williams, Carboline, Tnemec, PPG, Akzo-Nobel, Rust-Oleum, Comex, Benjamin Moore, or any other of the commonly-specified brands.

I mention this not to diss the products “anon” may be selling, but to clarify that “Epoxy 101” as linked above is a sales-pitch site tied to small manufacturers. It’s NOT a strictly generic technical reference; it also is pushing products outside the realm of commonly-used/supportive manufacturers and, if “anon” really believes his technical comments, uses dated technology in many cases.

We all mention brands now and then when they fit specific project needs, but those of us who do (me included) are not connected to any manufacturers.

IMO “anon” is a salesman and his “technical information” regarding epoxies is out of date. Many of the major manufacturers have made huge strides to get past the yellowing issues, chalking (not necessarily a defect - in some cases an advantage), and while there’s some good information on the several linked websites I located there are no specifications nor Architectural-specific project histories.

Not to play “forum cop” - but either “anon” is unaware of the basic forum guidelines for product reps or is ignoring them.

I just hope I’ve saved a few folks some valuable time. It didn’t bother me - this is the kind of thing I need to know about!

24

Jim,

I’m not a product rep. Just a lowly specifier. I agree that the web site is lacking, but the information is consistent with all of the “commonly specified brands” information about epoxy coatings that I have seen. It was not my intention to promote the products on this website, but merely to reinforce the fact that epoxies do not perform well for color, chalk, and fade when exposed to UV light.

I called my trusty Carboline rep to ask if there were any new epoxy products on the market suitable for architetcural exterior use that I should know about. “No.” he replied - without a moment’s hesitation. Carboline’s exterior urethanes are tested for color retention, chalking, fading, etc. Epoxies are not. Urethanes are the recommended coatings for durable exterior exposures. Epoxies are not. Opaque or transparent, makes no difference. And this is the same information I have received from Tnemec, Sherwin Williams, and Kelly Moore to name a few.

I would be very interested in knowing about new, technologically advanced epoxies that do perform well when exposed to UV, so if you know of any, please share. I am always on the lookout for new, innovative products.

25

Well, “anon” - refusing to identify yourself and linking to a sales site centered around one particular person’s “opinions” certainly looks like a sales push.

Your “trusty Carboline Rep” I’m sure is very qualified when it comes to Carboline/RPM’s product line, which has a firm foothold on the industrial market.

It’s just not the call I would have made - there are manufacturers that cover a wider swath of application types; also, there are small manufacturers that sell to nothing but the OEM market that most of the major industrial guys won’t be aware of.

I will make an assumption (usually a bad idea, but I think right on the money here) and state that from my perspective the Carboline rep answered your question based on his company’s product offerings.

I have worked with (and against, when on the sales/tech side with Tnemec and Rust-Oleum) Carboline many times, and at least in the SoCal market I have not found them to look outside their own loop for cutting edge products - not even within the RPM group (some reps are known for “poaching” accounts that are well-entrenched with their sister RPM companies.

"Carboline’s exterior urethanes are tested for color retention, chalking, fading, etc. Epoxies are not. "

Did he tell you that? Because it’s absolutely incorrect. Every one of the epoxy manufacturers I named tests epoxies for color retention, chalking and fading (plus yellowing, which you omitted).

“Urethanes are the recommended coatings for durable exterior exposures. Epoxies are not. Opaque or transparent, makes no difference. And this is the same information I have received from Tnemec, Sherwin Williams, and Kelly Moore to name a few.”

Really? Why are epoxies specified for exterior chemical containment areas that are exposed to UV light and other applications such as anti-skid ramps? Could it be that the abrasion resistance (as a rule) far exceeds most urethanes? Or are you simply wrong?

If you check with your SW rep, ask about Epoxy/siloxanes - good color retention and chalk resistance (among other advantages). And Polyamides in some formulations, water based epoxies and hybrids apparently defy your stated “basic law of resins”.

This is the frustrating part of consulting - convincing folks that historical characteristics, rumors and tales of woe regarding many coatings system no longer apply.

One huge disconnect, especially with larger companies (SW, Benjamin Moore, Kelly-Morre etc.) is that not all reps are well-versed in industrial coatings technology - not their own products or those of other manufacturers. Worse, store personnel are rarely, it seems, trained in heavy technical jargon.

But here are some simple facts:

We’ve already been given a source by a qualified Specifications Consultant for non-yellowing (I’ll fudge and say “reduced” yellowing) epoxies.

Here’s another - from the website YOU referenced. The link on your site goes to a very generic page stating Bio-Clear 810 yellows in weeks.

But here’s a statement from a site covering pourable grade epoxies, including specifics on the same product:

“When using pourable epoxy, make sure you use a non-yellowing epoxy, such as bio clear 810, by progressive epoxy polymers”.

To continue my surfboard-industry connection data: “Oceanside CA Jan 2011: After many epoxy resin versions, we introduce the XTR-20 , (20 min. pot life), that will solve all yellowing problems related to epoxy resins in general, This new resin was designed at Epoxy Pro only for surfboard lamination, for those customers who own an Epoxy surfboard that turns yellow this is the ultimate solution.”

Also note - I don’t know exactly what your Kelly-Moore rep told you about epoxies, but if it concerned their water based epoxies those are known for significant reductions in yellowing.

If it had to do with KM’s solvent-type or 100% solids epoxies - those are buy outs. They don’t even make them.

I’m not going to belabor this any longer, and simply close with these specifics:

  1. Colin posted a source that I’m going to personally check out, verify, and include in specs, as I trust Colin’s judgement and experience.
  2. My own experience with Sinclair (now Akzo Nobel), Vista, Tnemec, Rust-Oleum/RPM has proven there ARE suitable exterior epoxies, contradicting the “Epoxy 101” website (I would encourage those who have time…and most don’t…to look at parts of it, recognize it as a sales agency in disguise with faulty technical information - and not bookmark it!)
  3. I’ve dealt with dozens of other manufacturers as a contractor project manager - with the same progressive results.
  4. Far deeper research into performance of epoxies as a project and specifications consultant/inspector (plus coordination work with MPI) has proven time and time again that extensive progress has been made in epoxy technology that disproves the dated claims made on “epoxy 101” and its sister pages.
  5. While yellowing/poor UV resistance is an issue with some epoxy coatings, any statement tossing all epoxies into a bucket labeled “these products ALL discolor” is absolutely untrue.

“anon”, if you are truly a “lowly specifier” (I’m not sure if that’s a dig, attempt a humor or what) I’ll offer some free advice - don’t believe what you read on non-technical, haphazard websites. At the very least do some research on your own and perhaps contact a coatings consulting firm in your area and ask for some help, because if you really are not the person behind that website you have been led astray.

Good luck in the future. If you want to continue the discussion by email or phone please contact me - but this discussion doesn’t belong here.