Posts Tagged ‘synthetic inorganic’

Death of a Pigment

August 16, 2016

As I have posted before, we artists are at the mercy of much larger industries in terms of what art materials we have at out disposal. The art materials industry is minuscule compared to textiles, architecture, automotive, etc. It does not have enough clout to leverage economies of scale.

Without these larger industries to manufacture our pigments and other materials for us, these things would be much more expensive for us than they are. Without them, artists might have to actually make and mull their own pigments again – as artists and their apprentices from past centuries have done, as I and others have at times done.

A few pigments are still made by the art materials industry, for instance Winsor & Newton’s Rose Madder Genuine, and those tend to be the more expensive colors. But the vast majority of them are not made for artists at all. We just buy the leftovers from the bigger boys, and that’s how we get our pigments on the cheap.

To some extent, this has always been true. Even in the Middle Ages, the copper blue pigment (blue verditer) that was used by artists was manufactured as a by-product of silver production. But it is truer at this point in history than it ever has been before.

One of the results of this situation is that when a pigment is no longer deemed useful for the larger industries, its manufacture will cease. Cerulean blue (PB35), for example, may wind up on the chopping block at some point. If it does, it will not matter that many artists love this color: it will go away, for all except those who have managed to stockpile some for themselves.

This has happened to a pigment I happen to love: ultramarine green, PG24. PG24 is not considered useful any longer to the large industries, and as far as I can learn it has stopped being made. It is an extinct pigment.

It used to be available as a tube color in oil from Rembrandt. But the tube they call “Ultramarine Green” is no longer PG24, but a convenience mix of PB29 and PY129. It used to be available as a powder pigment from Kremer. No more. (They still have some of their PG24 watercolor pans left, I believe.)

In the next post, I will post some pictures to show what this wonderful pigment looks like, and why I love it so much and was so sorry to see it go – and what might be done to bring its production back online.

In the meantime, here is a closeup of a painting I did a couple of years ago, in which PG24 was used extensively, especially for that aqua foam on the water. To be continued!

wyoming_waterfall-2d2_800

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What is a sustainable color?

January 30, 2011

Or: the good, the bad, and the ugly

Despite more than a bit of misuse in popular culture, what the word “sustainable” actually means is simple – though the implications are quite profound for us all – and it’s this (from merriam-webster.com):

  1. : capable of being sustained
  2. a : of, relating to, or being a method of harvesting or using a resource so that the resource is not depleted or permanently damaged
    b : of or relating to a lifestyle involving the use of sustainable methods

So here’s my interpretation for the purposes of this discussion (and my own philosophy):

An activity is sustainable if it in no way impedes the ability of future generations to live their lives or to engage in the same activity or other activities – for all intents and purposes forever.

If an activity does not meet that test, then it is unsustainable. Can’t keep it up forever. Can’t sustain the activity indefinitely. If you try to keep up that activity forever, then eventually you crash. It’s a fail.

Sustainability is not a nicety. It’s a requirement and a hard fact. If an activity is unsustainable, then that means we will stop doing it – eventually. The only question is whether we cease the activity voluntarily, or are forced out of it through diminishing options – or whether we ourselves will meet our end before it becomes an issue. (As one cynic put it: We will keep doing what we do until we can’t any more, and then we won’t.)

So that’s my strict definition. But “forever” is a little hard for the human brain (at least my human brain) to comprehend and plan for. When I think about this stuff, I tend to think in more discrete chunks of time, because it’s easier for me, and it clarifies my thinking: five thousand years from now, ten thousand. Will our heavy industry still be consuming at its present rate in ten thousand years? Will the Three Gorges Dam still be standing? Will we still be mining for cobalt?

This, of course, is a blog about art materials, and more than anything else it’s about colors. So which colors are sustainable? Which are not? Which are finite, but nevertheless are abundant enough to probably last the long millenia?

The good

These are the materials that really could last pretty much until the end of the world. Non-destructive, renewable, natural organic colors (definition here) that can be raised or wildcrafted in one’s own bioregion (geographic backyard), and can replenish themselves, through careful horticulture or natural propagation, and can be prepared over a simple fire using abundant, locally available ingredients – these are probably the only colors that can be considered truly sustainable by our strict definition above. One can conceivably at least keep up that activity pretty much forever, so it does pass that test, assuming it’s done with care. (However, it should definitely be noted here that not all natural organic sources pass the test. More on that in the next post.)

Also, I think we can go a little easy on ourselves here and throw the natural earths into this category. Although technically they are finite (especially the nice brightly-colored ones), well, there’s just a heck of a lot of the stuff out there. It’s a little hard to imagine artists ever managing to use up all the red earth in Arizona – or Brazil.

The bad

The pigments that are most clearly unsustainable, for various reasons that should be fairly obvious, are the ones that are manufactured from petroleum or other hydrocarbons. These synthetic organics (definition here) are going to go away sooner or later – more likely sooner. For me this is the most easily identifiable group. Flatly not sustainable, because petroleum isn’t. End of story. I’ll actually be rather surprised if they manage to still be around for much longer than another decade or two.

Perhaps slightly less obvious are the pigments that merely require a hydrocarbon-driven industrial process for their manufacture. They may not have petroleum as their basic feedstock, but they are just as dependent upon it for their existence. I don’t see how this group can make it out of the cellar either. I’ll be going through a few examples in later articles.

The ugly

Any material which is finite is therefore, strictly speaking, unsustainable. However, common sense and a little research indicate that there are certain natural inorganic materials that are so plentiful (and in some cases highly recyclable as well) that we probably don’t really need to worry about them, at least not for a very, very long time. Iron and alum in particular, which can be used to make Mars pigments and lake pigments, will almost certainly not deplete completely from the major regions of the earth in any time scale meaningful to this discussion. Also, the minerals calcium, sodium, potassium and sulfur – also used in the creation of lake pigments and some other pigments – are in abundant supply as well. There are a few other materials that I also count as reasonable candidates for this group, depending on other factors.

So, luckily, I doubt we will ever be restricted to using natural inks and earths only, even though they’re the only materials that actually made it into our “good” category. (As much as I love natural inks, I do like to make an oil painting once in a while.) We’ll be collecting earths, and making lake pigments and a few synthetic inorganic pigments (definition here), for a long, long time to come.

Forever? Can’t answer that. Ten thousand years from now? Almost certainly.

Details to follow…

Pigment categories – the blurry lines

December 26, 2010

It’s hard for me to believe that I’ve let my blog go for five whole weeks. I never thought I’d be one of those authors who had to post “Sorry it’s been so long since my last post” – and yet, here I am. Sorry, folks. It’s been a tough month. I’m abandoning for this post, and maybe the next post or two, the discussion of classical underpainting techniques; but I am continuing to research and experiment, faithful reader, and I’ll return to the topic soon.

Back to art materials philosophy. Some time back I listed some basic definitions for the four categories of artist’s pigments: natural inorganic, natural organic, synthetic inorganic, and synthetic organic. (See the posts here, here and here.) The categories seem straightforward enough once you become familiar with them. However, things can get a bit weird if you start trying to nail down certain pigments.

Take Prussian blue, which is considered a synthetic inorganic pigment, in fact the first modern synthetic pigment. This is a pigment discovered accidentally in the early eighteenth century while attempting to create a carmine lake pigment with what turned out to be some tainted substances. What happened was that some potash contaminated with animal blood was used to precipitate the iron-based lake pigment, accidentally forming iron ferrocyanine, which makes a powerful blue. (Lucky accident!) So, but here’s the question: how is it that when a natural organic lake pigment received an additional natural organic element, it turned into something that is considered a synthetic inorganic? Weird – why is this pigment not considered a natural organic, like the carmine lake? I suppose it’s because in Prussian blue there is no actual dye involved – but still, it seems arbitrary.

A lake pigment is generally thought of as a dye precipitated onto a base of alum; but as indicated above, not all lake pigments are based on alum. They can be based on iron or copper instead, or even other metal salts such as chrome or zinc. Sometimes, even when a natural dye is used, these lakes based on other metals are viewed as synthetic, or semi-synthetic, rather than natural. Why? Why is a natural dye laked onto alum considered a natural pigment, but the same natural dye laked onto copper may not be? Alum is potassium aluminum sulfate, the copper mordant is copper sulfate pentahydrate. Both are metal sulfates, pretty similar stuff. A dyer would consider any dye obtained from natural sources to be a natural dye, regardless of what mordant were used to bind it to fabric, be it alum, iron, copper, tin, chrome or other, and I would agree – and I don’t really think of natural dyes laked onto different metal substrates as being categorically different from one another.

Precipitating copper blue

Precipitating copper blue

But I can easily get myself into more trouble. Green and blue pigments can be made from copper without the addition of a natural dye, and yellow and red pigments can be made from iron – and these are also considered to be synthetic pigments. But why? If laking a natural dye onto alum, iron or copper results in a natural pigment, then why does it become synthetic if I follow exactly the same procedure, but only leave out the organic ingredient?

It’s at this point that the whole question starts to break down. One person to whom I mentioned my interest in natural pigments immediately quipped, “Well, what’s natural”? At the time I confess I was a little irritated by such a flippant-sounding dismissal of what has been a passion for me – but now I see the wisdom in it, regardless of how it may have been intended. What is natural, anyway? Don’t get me wrong: the words “natural” and “artificial” are opposites with real definitions; but as soon as we start trying to identify categories, we have to start drawing lines, and that’s where things get messy. At some point you have to chalk it up to useless semantics and move on to another aspect of the discussion.

This is all a little illustration of why, though my original direction (years ago, now) was almost entirely about natural pigments, and though I still write about my love for colors from natural sources, I now pay little attention to such distinctions when considering my philosophy of materials, just as I now pay little attention to toxicity (other than as a necessary practical concern). Natural, synthetic, doesn’t really matter. What does matter, to me, is whether a particular art material is sustainable – meaning that I think we artists will pretty much never be forced to stop using it. That means no industrial processes required in that material’s production, no hydrocarbon feedstocks are used, no destruction of landbases necessary – and we aren’t dependent for our materials upon the needs of the giant automobile, plastics and textiles industries. In a perfect world, that would mean art materials that could be made locally, from regionally common materials, and without harming the ecolocality in any drastic way. The only pigments that are categorically excluded from my list are the synthetic organics; they are derived from hydrocarbons, and really can’t be considered sustainable no matter how they’re sliced. Also excluded would be any other pigments that absolutely require an industrial process for production. The ones that would not be excluded are the natural earths; the natural organic colors; and artificial pigments easily synthesized from common metals and minerals.

Yes, this is the kind of thing I spend my time thinking about. I think it’s important.

– L. Lawrence

The material basis of art culture

June 22, 2010

About a week and a half ago or so, soon after I’d made my last blog post about synthetic organic pigments, I noticed an article that ran in the Business section of our local newspaper (yes, the physical kind). It was titled Oil Is Everywhere. (The article is online here.) Since it was relevant, I became interested and looked through. Here is a quote:

Oil is everywhere. It’s in carpeting, furniture, computers and clothing. It’s in the most personal of products such as toothpaste, shaving cream, lipstick and vitamin capsules. Petrochemicals are the glue of our modern lives and even in glue, too.

Another:

“It’s the material basis of our society essentially,” said Michael Wilson, a research scientist at the University of California Berkeley. “This is the Petrochemical Age.”

Well, all I can say is that it’s about time someone noticed.

Gasoline is what tends to come to mind when we think of petroleum, but it is only one of the many, many products made from it. The stuff really is everywhere. To see that this is true, we artists need look no further than the materials we use today in the creation of our art. If petroleum is the “material basis of our society,” then it is also the material basis of our art culture. Not only are the synthetic organic pigments discussed in the previous post made from hydrocarbons, but so are modern varnishes, modern “gesso” for our canvas, mediums, inks, dyes, mineral spirits (solvents), paintbrushes, and acrylic and alkyd paints.

In the long term, none of these – nor any other petrochemical product – can be considered sustainable. The current abundance of petroleum is a short-term accident of history and geology; one day its production will decline (or perhaps before that time we will simply decide to quit using so much of it for environmental reasons, but I’m not holding my breath). When petroleum production declines, so will our current art culture.

If you took away our petroleum-supplied art products, many of us would hardly know how to paint any longer. If the modern synthetic inorganic pigments that have only ever been made with hydrocarbon-driven industrial processes were also taken away, we’d be in dire straits indeed. We’ve lost much of the knowledge that would allow us to paint effectively and expressively with simpler materials – “Old Master” knowledge, if you will. Such is the extremity of our reliance upon the industrial machine in this age. Art has always been coupled with industry, since ancient Egypt at least, but now art is almost wholly dependent on it.

Of course, when peak oil passes and world oil production begins to decline, the world will be busy with far larger issues than those revolving around the tiny art materials industry. But personally, I can’t help caring what becomes of our art culture. I don’t want our knowledge of natural and homemade materials to deteriorate to the point where we no longer know what to do without the modern industrial products. This is one reason – one of many, now – that I’m on this path.

Pigment categories – part III

June 6, 2010

I’m going to finally get around to tackling that last category of pigments, the synthetic organics. There’s probably a reason for my tardiness: this is my least favorite group, and one that interests me very little these days. Recall that the three we’ve done before were: natural inorganic (these were the earths and natural minerals); natural organic (lake pigments, other pigments that come directly from plants and animals); and synthetic inorganic (the great chemistry accomplishments of the nineteenth and twentieth centuries, ultramarine blue, cadmium red, etc.). The story of the last category begins in the nineteenth century, but is mostly a twentieth century phenomenon.

Synthetic organic pigments - watercolor

Synthetic organic pigments

To the right are a few quick watercolor swatches using synthetic organic colors. Along the top row, left to right, are: Winsor & Newton manganese blue hue (it’s phthalo blue PB15); Sennelier lemon yellow (hansa yellow PY3); and Da Vinci alizarin crimson (it isn’t: it’s quinacridone violet PV19. Aren’t these marketing names great?). On the bottom row are a couple of mixtures from the three, a bright green from the phthalo and hansa, and a warm red from the hansa and quinacridone. I didn’t include a violet, since this particular red and blue don’t make a very saturated one; but to get a nice bright purple one need look no further than another synthetic organic, dioxazine violet. (The photograph was taken when the paints were still partly wet, and it captured the colors only tolerably well; the hansa yellow in particular is a bit warmer and more transparent than it looks here. Photography is definitely a skill I need to catch up on.)

There are so few real natural organic pigments in use any longer – mostly just the various carbon blacks – that the word “synthetic” is generally dropped from the term “synthetic organic,” having no other category to make it necessary; and these colors are simply called “organic,” since they by and large are the only organic colors out there. The name is a bit misleading at first. Most of us tend to feel a bit fuzzy when we hear the word “organic” – after all, usually it means healthy; it means natural; it probably means eco-friendly, cage-free, free-range, no hormones or pesticides, etc. However, in this case “organic” simply means that the substance in question contains a carbon molecule, and the feedstock from whence it was created probably existed, once upon a time, in the form of actual organisms. I’m talking, of course, about hydrocarbons: petroleum, natural gas, coal, etc. These substances are industrially heated, pressured and combined in various ways, sometimes with industrial acids or other chemicals (my knowledge is very weak on details here), to create the synthetic organic substances. Hmm… my fuzzy feeling has suddenly gone away.

From the Encyclopedia Brittanica: “Synthetic organic pigments are derived from coal tars and other petrochemicals.” By “coal tar” they mean the residue byproduct from burning hydrocarbons such as coal or natural gas. Some coal-tar colors began in the nineteenth century as dyes: mauve, alizarin crimson, the aniline colors – and some of these were laked to create the first synthetic organic pigments. (Some are insoluble to begin with, and don’t require laking.) The twentieth century embraced and expanded upon this line, notably with the azos, the phthalocyanines, the quinacridones, the perylenes, the anthraquinones, the pyrroles.

These are consumer colors – bright and saturated, capable of being produced on a tremendous scale, and cheap. They are truly modern colors, not only in the history of their production, but also in their flash and chromatic glory. Without these colors, the commercial world around us would be much less colorful than it is.

The benefits of these colors for artists are often cited. There is the very full range of color they make available to the artist, the ability to mix almost any color that could ever be needed by the average painter. They have provided excellent, durable replacements for older, less lightfast natural organic colors that have been weak spots in artists’ color wheels for centuries. They are inexpensive compared to some of the synthetic inorganic pigments, such as the cadmiums and cobalts. Finally, they are a less toxic alternative to those cadmiums and cobalts, and are increasingly turned to as the more toxic metals are falling under legislative ire.

So: what’s not to like? Follow me on later posts, faithful reader…

Availability of high-chroma colors?

February 8, 2010

I’ve been thinking quite a lot lately about a limited palette, and what it means to me as an artist, and which colors I might choose. We are so used to having bright, saturated colors available to us from the art supply store – but I’m not convinced that they will always be there for us. Not all of them, at any rate. I still haven’t gotten around to making the final “pigment categories” post about synthetic organic pigments – I’ll do it soon, I promise – but the short scoop is that the synthetic organics are manufactured from hydrocarbons: petroleum and gas residue (called coal tar). Hydrocarbons are, obviously, a limited resource, as well as currently causing intolerable environmental problems for us. Sooner or later, hydrocarbon production will decrease, and when that happens, the colors currently made from them, and many other things, will begin to get more expensive.

Even the availability of some of the synthetic inorganic pigments I posted on a couple of weeks ago is not reliable in the long term. Cadmium, from which cadmium red, cadmium yellow and cadmium orange are made, is becoming a real problem environmentally – is it prudent for us to continue using it? Given the recent issues with cadmium content in children’s toys from China – well, this is the sort of thing that can lead to legislation. And cadmium is generally produced as a by-product of zinc production. Does that mean zinc white is out too? As it turns out, zinc production has its own slew of environmental issues associated with it. And what about the cobalts? These are just a few examples.

high chroma portrait painting

high chroma portrait painting

Thing is, I’ve become rather attached to these colors just lately too. The cerulean blue I was talking about last post is a color made from cobalt and tin. And just this week I’ve begun a new direction in my thinking about color in painting – using color temperature as a partial stand-in for value, and painting much higher-chroma than I ever did before. Here is my attempt from class (and with help from my instructor).

Obviously there’s a lot wrong with it… it’s my first real attempt at something like this. But artisticially, I like the direction it implies. And that’s got me thinking. Two hundred and fifty years ago, not one of the colors I used in this painting was available to artists. Are we certain they are going to be available into the indefinite future? Or, even if they are: at what price?

This is just an introduction; I have a lot more to post about these things. Suffice to say, for the moment, that I believe we occupy a marvelously rich moment in history, in the colors we use for our paintings as in so many other things. And as these colors do not stretch into the distant past, they also may not stretch into the distant future. Something to which most artists don’t give a moment’s thought, but it’s worth thinking about nevertheless. What colors are really sustainable, and which ones are unsustainable – and what will we do without them?

Portrait completion

January 25, 2010
portrait from life

portrait from life

Here is the more-or-less completed painting, one week later. It was done in class over a period of three hours with some breaks in between. My instructor helped me out at the final stages, bringing the colors more in harmony and expanding upon the cool range in the shadows of the flesh tones.

The colors used were a combination of mostly synthetic inorganics, with two synthetic organics (the organics occupying, as usual, the cool red part of the spectrum): cadmium yellow light, cadmium orange, cadmium scarlet, quinacridone rose, alizarin crimson, ultramarine blue, cerulean blue and viridian – with titanium white. No black was used, the darks were attained by mixing complements. Most of the darkest darks included some ultramarine or alizarin, as those are the deepest and most transparent colors on this palette.

This is an unusual approach for me, not only in the use of ultramarine blue for the underpainting as I mentioned last week, but also in using so many high-chroma colors for skin tones in a portrait painting. I’m used to using the Zorn palette, which is just a vermilion hue (or the real thing if want to hurt your wallet) and yellow ochre, plus black and white. The way we worked for this project was very different. I can see some benefits, including seeing temperature differences more clearly, learning to better control the more saturated colors, and having more options for brighter rendering of clothing and drapery (the model’s violet sweater and scarf would have had to be much duller using the Zorn palette). I did miss using yellow ochre quite a bit – I found the bright cadmium yellow light was the most difficult color on the palette to control.

But the chief benefit was the addition of those two blues to the palette – ultramarine for real darks and cerulean blue for wonderful cools in the reflected light and shadows of the skin tones. Cerulean blue PB35 is a stannous cobalt that came into use in the mid nineteenth century. I enjoyed using it quite a bit, as I’ve enjoyed several other synthetic inorganics from that time. Not only does cerulean blue possess a delicious color and nice opacity on its own, it also behaves itself in mixtures, not dominating as other cool blues such as Prussian blue or phthalocyanine tend to do. I think I’ve found a new permanent addition to my portrait palette – “permanent” being relative, or course. According to some professionals, cerulean blue is the pigment most in danger of being discontinued by manufacturers, for reasons I’ll go into in another post. Figures.

portrait palette cools

portrait palette cools

I also enjoyed using the viridian, another synthetic organic from the same period (as is artificial ultramarine, for that matter) – it was great for cooling off and desaturating the reds and oranges. This is another color that behaves itself in mixtures a lot better than the phthalos. It was a favorite of Cézanne’s, whose work I’ve always admired, and is as bright as green as I can imagine ever needing. On the right is an image of some of the shadows using ultramarine, cerulean and viridian. I’ll be happy to get rid of the cadmium yellow light and switch back to yellow ochre – but those three cools will stay on my portrait palette, at least for now.