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-   -   Odorless solvent (http://portraitartistforum.com/showthread.php?t=8311)

Allan Rahbek 12-18-2007 02:25 PM

Odorless solvent
 
Anybody heard of a thinner for artist colors, that is based on "isoparaffin-based odorless solvents".?

This sounds like an ideal solvent / thinner for oil colors. It is said to NOT contain any harmful ingredients, neither for the artist or the paint ,according to conservators.

It contains less than 0,01% aromas and evaporates slower than turps

Richard Bingham 12-18-2007 04:34 PM

Alan, much depends on what one's purpose for a "paint thinner" may be, in terms of oil painting. Solvents, (regardless of their composition) ultimately destroy the binding character of vehicle oils and resins by over-extending them, rather like a rubber band ultimately fails when over-extended.

"Isoparaffin based" is a fancy-schmantzy way of saying the solvent is a petroleum distillate. In other words, it's mineral spirits. Mineral spirits is basically refined kerosene. For use cleaning brushes and tools, kerosene is superior to mineral spirits, because it is more penetrating, and with a lower vapor pressure, less is emitted into the air. Odorless varieties of mineral spirits are not necessarily "safer" for the atmosphere just because you can't smell it.

Back to oil paint, pure gum spirits of turpentine is no more nor less toxic or "unsafe" in the studio environment than mineral spirits. Resin varnishes (including mastic, damar and copal) cannot be satisfactorily compounded with mineral spirits, because the petroleum product causes varnishes to be cloudy. As a solvent component of mediums, turpentine provides a different chemistry which promotes interior drying of paint films. In the main, a painter's use of any solvent is (or should be) so minute as to be less than problematic in terms of air quality safety. In all cases, the studio environment should always provide ample ventilation and fresh-air exchange.

The toxicity of turpentine has become a "hot issue" in some circles. This is probably due to the current prevalence of solvents touted as "turpentine" which are NOT pure gum spirits of turpentine. The last few years, most "turpentine" has been bulk-manufactured in the far east by steam-distilling forest wastes of indiscriminate species. Stumps, limbs, roots and slash are ground into a pulp which is cooked to yield a distillate solvent which reeks of creosote, and a number of active terpene toxins. It has no use in the studio for any purpose.

Good turpentine is the gum exude of certain conifers, tapped from living trees. The spirits of pure gum turpentine are the distillate. Rosin, colophony, and spirits of turpentine result from the process. Good turpentine smells clean, like a pine forest after a rain. That it is not necessarily "toxic" is proven by its long duration as a staple in liniments and cosmetics.

Thomasin Dewhurst 12-18-2007 04:59 PM

I have used something called Turpenoid, which is apparently odourless turpentine. It is, I think, no less harmful or toxic than ordinary turps, but it doesn't have a smell at all. Not sure how they make it (perhaps Richard would know). This I would use for mixing with oil paint. There is something else I use which I think is mineral spirits (it, mysteriously, has no ingredients listed on the label). I use this only for cleaning brushes as it strips all paint, dry or wet and if you used it on your painting I am sure the paint would start peeling off altogether!

Richard Bingham 12-18-2007 06:08 PM

Turpenoid is odorless mineral spirits, as is Gamsol, and a number of other items marketed especially to "arteestes" under clever names. The implication is there is something "sensitive" and wonderful (or ecologically sound) about materials made "just especially for us, the select few." It all comes out of the same tank-car. Know thy materials!

Re/ solvents . . . a number of petroleum distillates, including kerosene, mineral spirits, xylene, benzine and "white" gasoline are all capable of attacking the structure of drying oils and some resins. Some are more active than others, some are more volatile. These are properties that may or may not be conducive to one's ends in the studio.

Given that most of the oil paint one buys these days is mulled in safflower oil, (which requires a siccative to dry within our lifetime)and produces a polymer film infinitely weaker than does raw linseed oil, I would recommend adding at least 20% by volume of good, raw linseed oil to any solvent used to "thin" oil paint.

Allan Rahbek 12-18-2007 06:41 PM

Richard,
it say's that "the active part is Isoparaffine 222" and that it is not the same as odorless turpentine and that it will not cause "painters syndrome".

Have I understood it right when saying that "Odorless Turpentine" is made from Mineral Spirit and not from Vegetable Turps?

Richard Bingham 12-18-2007 07:39 PM

Hi Alan, what in heaven's name is "painter's syndrome" ?!?
I suppose a petroleum chemist would be familiar with "isoparaffin 222". Here's the deal. Mineral spirits in all its grades and species is a petroleum distillate, and an aromatic hydrocarbon. Breathe enough of it, and you'll get sick.

IMO, there is only one acceptable "turpentine" for oil painting, and that is the distillate of gum collected from Georgia (USA) pines, and in previous times from similar conifers in Portugal.

To the best of my knowledge, no one has removed the odor from pure spirits of gum turpentine. Why would you ? It doesn't smell bad, and most of these materials nowadays are going into air-fresheners and cleaning compounds so that they will smell "pine fresh".

Turpenoid is not a "natural" (vegetable, if you will) solvent, but a mineral spirits variant.

Allan Rahbek 12-18-2007 07:48 PM

Quote:

Originally Posted by Richard Bingham
Hi Alan, what in heaven's name is "painter's syndrome" ?!?

It's the name, in Denmark, for the disease painters get when exposed to too many fumes from turps, one forgets, much like lead poisoning.

I never use Mineral Spirit for deluding artist color, only Vegetable Turps ( also called "French Turpentine" )

I would use the Isoparaffine 222 for cleaning brushes, I think that the smell of Vegetable Turps is delicious but it can be a little too much sometimes.

Alexandra Tyng 12-19-2007 01:49 PM

Although I consider myself an artist rather than an "artiste," I use odorless solvent (Gamsol). The reason is that I became very sensitive to the regular turpentine (any form including gum). Whenever I painted with it, by the end of the day I developed respiratory problems. Odorless solvent reduces this problem dramatically, perhaps because it doesn't evaporate as fast? I'm not really sure why, but for whatever reason it works for me.

Allan, it sounds like this product might be simply another brand of petroleum-based odorless solvent.

Richard Bingham 12-19-2007 02:30 PM

Alexandra, please don't take my rough humor re/"arteestes" as an affront. I tend to wax a bit radical over: a. how the state of art instruction through the last 100 years or so has short-changed the physical, craftsman-oriented aspects of the art of painting, and b. those who see the dearth of painters knowledgeable about their materials as an opportunity to tout otherwise cheaply available common items as something "uniquely special" . . . at ten times the price.

Any sensitivity to even "good" turps you have experienced only proves that a definite qualitative difference between pure gum turpentine and mineral spirits exists. My father, who was an active painter all of his adult life developed a contact dermatitis from turpentine when he was in his late 60's. As mysteriously and sudden as it came on, it left him in the same manner within a few months. There are people who are allergic to roses, common house plants, pets and foods . . . of course you have to maintain your personal comfort level. That's only sensible.

The vapor pressures and hence the emissions from either odorless MS or good turpentine are so close as to be a negligible difference.

Alexandra Tyng 12-19-2007 03:50 PM

Richard, I truly wasn't offended--just a friendly jab. I couldn't resist. :D


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