Waterborne Lacquer's Dirty Little Secret

[Mike Henderson]

I've been using Target waterborne lacquer for several years and have been satisfied with it. The other day, I had a situation where some water got on a project and I didn't notice it until the next morning. The finish had become cloudy, almost white.

I couldn't figure out what had happened - why would lacquer turn white like that. Just by coincidence, I was talking with a friend and mentioned the problem to him.

He said, "I'll bet you used an acrylic finish."

I said, "Yes, the waterborne finish I use is acrylic."

Then he told me, "That's the way acrylics work. It doesn't matter how long the finish has cured, it you have water sit on it, the finish will absorb the water and it'll cloud up. But it should go away if you give it enough time to dry out."

I had no idea that acrylics worked that way. I thought they were just waterborne versions of the old nitrocellulose lacquer, and the characteristics would be the same as nitrocellulose lacquer. Now, I have to tell people to make sure water doesn't sit on the furniture or the finish will turn white.

Anybody know of a waterborne lacquer that will give a good shine and not exhibit this kind of water absorption?

Mike

[David Weaver]

I don't, it happens to mine, too. But the same happens for me on everything (shellac, etc) except polyurethane (I haven't tried nitrocellulose). I usually don't think much unless I come back a couple of days later and the surface is still clouded.

[Brian Kent]

Thank you for the warning. Waterlox shows no such tendencies.

[Mike Henderson]

I don't, it happens to mine, too. But the same happens for me on everything (shellac, etc) except polyurethane (I haven't tried nitrocellulose). I usually don't think much unless I come back a couple of days later and the surface is still clouded.
Yeah, I was aware of the problem with shellac, but I had used nitrocellulose lacquer before going to waterborne and it was a good finish - no problems of water absorption - and thought the waterborne was pretty similar.

For Brian: Waterlox is a solvent based finish, I believe, and cannot be sold in CA. Solvent based finishes wouldn't have this problem, I don't think - never heard of them doing this.

Mike

[Howard Acheson]

>>>> I thought they were just waterborne versions of the old nitrocellulose lacquer, and the characteristics would be the same as nitrocellulose lacquer.

That's what the finish manufacturer want you to think. The following is and excellent treatise on the subject of waterborne finishes.

QUOTE

It really makes no difference which you use waterborne lacquer, shellac or varnish since they all are simply water-borne acrylics—neither is really lacquer, shellac or varnish (poly). These are simply terms created in the marketing department intended to stimulate sales. In Understanding Wood Finishes, Bob Flexner puts it this way:

"(Water-borne finishes are) often called lacquer, shellac or varnish for marketing reasons. It makes an entirely new type of finish seem familiar. Water based is often called polyurethane for the same reasons when some polyurethane resin is blended with the usual acrylic resin. This interchangeability of names adds to the confusion about finishes. When you hear or read that someone varnished a table, it could mean he or she applied either of the evaporating finishes (shellac or lacquer), a reactive finish (varnish), or a coalescing finish (water base)."

With nothing but the highest respect for Bob Flexner, I am a bit less charitable (his book is very high on my recommended list when it comes to explaining finishes, what they are (and aren't), and how they work). I believe there may have been a time when the "name game" was intended to foster a degree of familiarity. However, water-borne finishes are no longer new, and their basic formulation has not changes since they were first introduced. The "creative naming" taking place today is done with the plain and simple intention of misleading—and, it works.

While it is true that the Minwax product (and similarly labeled polyacrylics) contain a small amount of urethane resin, the dominant resin in all water-borne finishes is acrylic. There is virtually nothing about these so called "water-based polyurethane" finishes that can be compared to oil-based urethane resin varnish. Therefore, what you have read about the negative attributes of poly applies only in the most peripheral sense to water-borne acrylics with urethane resin added. The only major similarity is that they (acrylics) should not be applied over shellac that contains wax.

In the context of your question, by wondering if "lacquer will do the job" you are, in effect, wondering if a water-borne acrylic from a different can and sold under a different name will do any better. Again, your "lacquer" isn't lacquer unless we adopt a definition of lacquer that is so broad that it can be wrapped around any liquid finish that dries or cures to form a finish film. (If we do that, your water-borne poly will also be lacquer.) In this instance the manufacturer uses the term "pre-catalyzed" in an effort to link its product with the true pre and post catalyzed lacquers. Again, this is nothing but marketing subterfuge. In all likelihood, the manufacturer has simply added a "hardener" to the finish. This is a chemical that creates a sort of "cross-linking" reaction within the finish for the purpose of making the cured film more durable in the face of heat, solvents, acids, alkalis, water, and water-vapor (the typical water-borne finish does not do nearly as well in the face of these hazards as an oil-based finish). This hardener is frequently added to water-borne finishes that include KCMA finish durability success in their advertising. The downside is that this hardener is very toxic, thus eliminating one of the benefits of using a water-borne in the first place. Furthermore, the finish film is still inferior to oil-based varnish in the face of these hazards.

Next, you need to understand that neither of these "water-clear" finishes is going to match the color of the previously applied nitrocellulose lacquer. You will have to add color using small amounts of water-soluble dye.

Finally, it is not my point that there is anything "wrong" with either of the finishes that you propose to use. They are what they are and they are defined by their own set of advantages and disadvantages dependent on the proposed application. Rejecting one or adopting the other based on what you have read about a completely different type of finish when, in reality both of these are the same, would be pointless. I am simply saying that they are: 1) both basically the same thing, and 2) they are not what they are advertised to be. You may as well use what you already have.

But my point has to do with drawing reasonable conclusions with respect to whether or not there are fundamental differences in water-borne finishes. I’m not going to get into a detailed examination of MSDS documents beyond my observations below. But first, let me address the issue of KCMA and marketing practices.

KCMA finish certification requires four tests as described in the link. For a manufacturer to advertize that their finish “meets” KCMA requirements and for said finish to actually be KCMA Certified is not the same thing. May I point out that we have a number of manufacturers who claim that their finishes are “food safe” when in reality there is no prescribed testing to support these contentions? Let me also point out that the same finishes sold as “food safe” are packaged in other cans and no such assertion is made. We are also treated to “Tung Oil Finishes” that contain nary a drop of tung oil; and to TV woodworkers who claim to use some magic oil when in reality they are simply applying wipe-on polyoneverythane. In the world of finishes, marketing claims and fact tend not to reside together.

Let me also point out that neither Target nor Fuhr are listed as KCMA members in the Finish Material Section of the KCMA Directory. Companies like M.L. Campbell, Sherwin-Williams, Valspar, and Mohawk are. These are companies that produce products (not necessarily available to the general public) that have obtained certification.

But, to my point about the similarity (virtual sameness) of water-borne finishes; all water-borne finishes share three common ingredients that make up nearly 100% of the contents. Further, the proportion of these primary ingredients tends to be remarkable uniform from brand to brand. These components are 1) water (typically 50% to 60%), 2) Acrylic Resin (usually somewhere between 20% and 30%), and 3) Glycol Ether (about 10%). In those water-borne finishes that are advertized as “water-based poly” the acrylic resin is typically reduced on the order of 5% to 7% to make room for an equal amount of “polyurethane”. Other chemicals are added in significantly lesser amounts for the purpose of improving various properties. For example, flow-out in water-borne products formulated to be padded or brushed; and, to reduce foaming in those designed to be sprayed.

But, my point was that neither Target nor Fuhr are fundamentally different from other water-borne finishes. Certainly there is nothing in their formulation that makes them superior to other offerings that may be available locally. I call your attention to the previous list of KCMA members that supply finishing materials. I also call your attention to the following notice copied from the Homestead Finishing Products website relative to this vendor’s decision to discontinue Fuhr products:

“Effective January 1st, 2007, Homestead is no longer a stocking dealer for Fuhr Finishes. Replacements for Fuhr product will be suggested as Fuhr stock is sold through. We regret this inconvenience, however most Fuhr product will have direct replacements with Target or Enduro/General waterborne finishing products. “

In other words, you will get the same result with Target and General Finishes that you got with the Fuhr product line, which is being discontinued. May I be so bold as to suggest that the list of replacement products would be even longer if Homestead also carried products from M.L. Campbell, Mohawk, etc? Please don’t misunderstand, my point is not that Homestead is being disingenuous—we all market what we have, that’s the nature of retail. My point is that the loss of Fuhr (for whatever reason) from the product line is no big deal. Neither would the loss of General Finishes or Target have posed a problem in terms of the ability to provide a finish offering equal properties and capabilities. There is a whole world of functionally equivalent water-borne finishes ready to step in and fill the gap.

If you like Fuhr or Target and you are willing to pay the cost of shipping to get them, great. But, to suggest that they are somehow unique, and therefore fundamentally superior to products that may be available locally, is a far more difficult position to defend. Apparently Homestead is of the same general opinion—clearly they believe that they can put Target or General Finishes in the box in place of Fuhr and their customers will detect no difference…

Steve

CLOSE QUOTE

[Brian Kent]

Mike, I found out one of Waterlox's "dirty little So Cal secrets". You cannot buy them in Los Angeles, Riverside, Orange or San Bernardino counties, but you can get it in quarts in San Diego. I picked some up a few days ago at Rocklers on Clairemont Mesa Blvd. The have both the Sealer / Finish and the Satin. The online sources won't ship anywhere in California though.

[Mike Henderson]

Thanks for the info, Howard. That's a good posting.

A couple more questions for anyone who knows:

It seems that waterborne pre-catalyzed "lacquer" would be more durable than the acrylic sold as lacquer. Anyone have experience with this? Will pre-catalyzed lacquer blush white if water is left on it?

Also, will pre-catalyzed lacquer "burn in" to a previous coat if the coats are applied close together, say within a few hours (while allowing the first coat to cure)?

Mike

[David Weaver]

Dipropylene Glycol Monomethyl Ether

That's what's in the target crosslinker. I can't find anything on it. I do, though, have a pregnant wife and I'm getting ready to spray some cabinets with EM6000. My wife will obviously not be in the room, I'll be spraying in the garage, but there is a bound to be some small amount that makes it into the house, be it 1% of the vapors or whatever.

Do you know what the toxicity issues are with the crosslinker, and should I just forgo it instead? The days I'm spraying, I'm intending to send my wife off to a friends house and I'll probably do it with the house windows open before she gets back.

Might sound like an overreaction, but it is what it is.

[Harold Burrell]

Dipropylene Glycol Monomethyl Ether

That's what's in the target crosslinker. I can't find anything on it. I do, though, have a pregnant wife and I'm getting ready to spray some cabinets with EM6000. My wife will obviously not be in the room, I'll be spraying in the garage, but there is a bound to be some small amount that makes it into the house, be it 1% of the vapors or whatever.

Do you know what the toxicity issues are with the crosslinker, and should I just forgo it instead? The days I'm spraying, I'm intending to send my wife off to a friends house and I'll probably do it with the house windows open before she gets back.

Might sound like an overreaction, but it is what it is.


The only thing I know for sure is that you should not spray the EM6000 directly into your wife's mouth or nostrils.

[David Weaver]

The only thing I know for sure is that you should not spray the EM6000 directly into your wife's mouth or nostrils.

Hopefully, I get a mulligan on that. I might need one.

[Rich Enders]

David Weaver.

If you Google DiPropylene Glycol Monomethyl Ether there are a flock of hits. I downloaded one from a manufacturer (Dow), and one from OSHA. I tried to attach them to this reply, but .pdf is not supported. You should be able to download them yourself, or I can email them to you.

[David Weaver]

Yeah, I did look at them. None of them are good, and most of them state that toxicity is relatively low for moderate skin contact but describe that inhalation should not occur and that an unexpectedly large amount of inhalation would result in extreme discomfort and a large dose no matter what could lead to organ failure. Now, I'm sure you could say that about a lot of things, but I wouldn't breathe most of those, either.

But my concern isn't me, I could tolerate it. It's how much more extreme the results usually are on a fetus, even at much lower doses of things (like methyl alcohol vapors, latex paint VOCs, etc).

[John Coloccia]

re: all waterbased finishes being the same.

That's not even close to accurate. Instrument makers have been trying various waterborne finishes for many many years searching for an acceptable finish. Target is by far the best of the bunch at the moment, and there are vast differences in performance between different formulations, not the least of which is EM6000's ability to be repaired with no witness lines. I know of no other waterborne acrylic that can do that, and in fact not all of Target's waterborne acrylics have that property. There are other performance differences, but just that one difference is very significant on it's own.

It's also inaccurate that there is some trickery going on:

http://www.targetcoatings.com/shop/catalog/EMTECH_6000_Production_Lacquer-32-1.html

I don't know how anyone could miss the word "acrylic" written in big letters on the can, or in the very first sentence of the description. We've been calling acrylics lacquer for as long as I can remember, and probably longer than that.

[Jamie Buxton]

I haven't invested in the facilities to spray conversion varnish, so I can't comment on that part of this thread. However, I've sprayed a lot of waterborne, and have some suggestions for the OP.

* Spray a couple more coats of the waterborne. The way I spray, three coats *looks* like it is sufficient coverage. However, four coats is a lot more resistant to household chemicals, and five coats is a little better than four. I use three coats for furniture that doesn't get much stress, like bookcases, but kitchen cabinets get five.

* Try a different waterborne. I now use General Finishes Enduro Clear Poly. In my tests, it is more resistant to water and Windex than the Target PSL/USL I used to use.

* Wait long enough to ensure the finish is cured. You can sand waterborne in a matter of hours, so you'd think it is cured. However, it actually gets more resistant to abrasion and household fluids if you let it cure longer. Five days is good. Two weeks is probably diminishing returns. (I dunno why this is true. I can't believe there's a chemical reaction that takes days. Maybe what's happening is that the solvent in waterborne -- ethylene glycol -- is slowly outgassing from the film.)



BTW, here's the way I test potential finishes. Long ago, I found out the hard way that finish manufacturers are, um, optimistic about their products. Now, when I'm considering using a new waterborne, I test it first. I cover a test board with the finish. I usually put different numbers of coats in various areas on the boards. As I'm doing this, I observe how easily the finish sprays, and whether it is easy enough to get a smooth coat. I wait until the finish cures. Then I make puddles of various household fluids: water, soapy water, cooking oil, vinegar (for acid), windex (for alkali), red wine, and high-proof alcohol like vodka. I watch the puddles for a day, and note any damage. If any of the fluids evaporate before the end of the day, I replenish them. Over the last twenty years, I've seen better and better performance on these tests. On my current choice, the General Finishes Enduro Clear Poly, there's only two fluids that have any noticeable effect: vodka, and windex. The vodka effect is a slight ring in the sheen around the edges of the puddle. The windex effect is a slight bulge in the surface, as though the ammonia lets the water penetrate the finish to swell the wood underneath. Straight water has no observable effect.

[Jamie Buxton]

One more possibility... General has announced a new waterborne which I have not yet tried. It is a two-part finish. That is, you mix two components together just before you spray. Curing is more by chemical action than just by solvent evaporation. (http://www.generalfinishes.com/professional-products/water-base-topcoats-and-sanding-sealers/conversion-varnish) It should be more resistant to household chemicals.