Art Materials FAQ

Version 1.2

Last updated: September 2, 1995

Written and maintained by R'ykandar Korra'ti <>. Sourced from a message in reply to Tygger <> on Comments and corrections to

This article, a more formal version of a long post I made on, is intended to discuss materials commonly used in illustrative artwork, and the durability thereof. It will also comment briefly on how to preserve the artwork you purchase. The intended audience is comic, illustrative, and fan artists, the people buying or otherwise acquiring artwork from these same sources. It is not a fully-comprehensive treatment of the subject, but is intended as a good set of ground rules for how to make artwork - particularly artwork done on paper - last.

This version reflects changes and contributions suggested by the following:

Sections with significant amounts of new text or information are noted with individual contributor credits. I hope this is not too confusing.

This is version 1.2 of this FAQ. Version 0.1 was my response to Tygger. Please direct suggestions and error corrections as outlined above.




In article <> (Tygger) wrote:
Now, here's the interesting part: now I'm being told that an illo coloured in marker or an illo with marker and enhanced by colour pencil isn't up to par to warrant a min bid of $35-45 in an artshow. It's due to the marker, I'm told.
I'm not surprised, at all. I know I adjust my bid based on media - or rather the durability thereof - and will avoid several processes entirely, regardless of how much I like the work.

All the materials used to make artwork affect the durability of the final piece. While this may seem obvious when stated, many artists and collectors never really think about this when creating, selling, or buying work.

Pigment and Dyes

The list of commonly used tools and media includes All of these bring with them different issues, both across class of material (magic marker ink vs. brush ink vs. oil paint, etc) and across brand of manufacture.

In all cases, there will be one of two classes of colouring agent in the medium. Most markers - particularly colour markers - use dye. Dye is always relatively fugitive (or transient, or whatever). It is very much likely to change colour or fade completely; how definite it is that this will happen, or how quickly it will happen, depends upon the dye in question.

One of the biggest problems, generically, is "drift." "Drift" is a general term indicating one of several issues, most notably fading, colour change (or "shift"), or outright spread of the colour in an unexpected and undesirable way. The first is most common; the third, least so, but still happens.

Pigments are overwhelmingly more likely to last, both in the face of time and sunlight. Pigments are found in a very small number of non-refillable pens, in all "India inks," in better watercolours, acrylics, and so forth. Some pigments - particularly modern experimental pigments - can also drift, shift, or fade, but this is much less likely overall. Elemental carbon (the pigment used in "India ink") will _never_ exhibit this behaviour.
[Decision to explain dye vs. pigment prompted by Victor Wren and Neil McAllister. Much data to correct prior errors on this subject was provided by both.]

Black line markers:

Markers drift. In fact, they drift badly. They're the most ephemeral of media in common use today. There are a few which are stable (Micron Pigma pens come to mind; black today, black tomorrow, black next decade), but most aren't. How much they end up drifting depends upon how much light exposure they get (and it does _not_ have to be direct sunlight), as well as the air circulation, the paper they're used on, and probably half a dozen other things. Plus, as mentioned above, it varies by marker.

Known stable: Micron Pigma technical pens

These are available from .005 to at least .08cm. I've surveyed a few dozen pens, and this has been the only one I've found to be considered generally stable. The reason is that they actually use pigment-based ink, rather than dye-based, having come up with some way of grinding the pigment finely enough that it can pass through a marker-type delivery system. One minor drawback: the pigment can be rubbed off to a degree by an eraser, resulting in some lightening of the ink marks. Keep this in mind when working.

Do NOT use: Pilot Razor Points.

They're hugely popular because they feel very good. Don't expose them to air or light, though, if you want to keep your work's black lines _black_. They fade to grey or green. They're also water-soluble, even when dry. (On the other hand, if you only intend to keep the work for a couple of weeks - say, it's a test sketch - then there's no need to be concerned.)

Thick black markers

I've encountered none which are stable. I've been told that this has to do with the delivery method; the constraints put on the ink by the felt process prohibit the use of any pigments, so they're all dye based.

Watch out for: Sharpie(R) brand.

They produce a _lovely_ black and are really fun to play with. I still play with them when I'm touching up a photocopy for submission to a magazine, or when I'm just screwing around - but I've heard from several artists that they not only turn green, but produce a yellow bleed on the paper. (I've seen some hints of this yellow bleed myself.) This is chromotography in action, and is independent of the paper used. They also used to contain a rather nasty solvent, but that appears to have changed recently.
[R'ykandar Korra'ti; Araiguma]

Also, old Pantone (TM) and the current Design (TM) lines of thick markers use Xylene. Use only if you've got good air circulation.
[Victor Wren]

Thin colour markers

I've never seen anyone use these. Micron makes colour tech pens, and I've recently been told that they, too, are micropigment based and should therefore have some degree of durability. However, they only make four colours - red, green, blue, and black.

Thick colour markers:

Colour markers drift overall more than B&W, since colour shift becomes a more crucial factor. Letraset made a Pantone line which claims a fair degree of stability, but watch out for that lovely smell of solvent (Xylene; mildly carcinogenic; work in a well- ventilated area) - it's bad fer ya. Plus, they bleed (upon application, _not_ later - at least, so far) more than any other marker I've ever used. Work I've done with these (and touched up with Marvy brand small-points - I know, eew, but the name isn't my fault) has held up so far, when maintained properly. However, I'm not holding my breath on the Marvy durability, and have been informed [by Araiguma] that the dyes therein are not particularly lightfast. Also, be careful when applying these to colour photocopies; Xylene will dissolve some colour photocopy toners, resulting in a "muddy mess."
[R'ykandar Korra'ti; Conrad Wong; Araiguma; Victor Wren]

Letraset is now making a new line called Tria, which has three separate tips of different sizes. They're also dye based, but the solvent is now 100% alcohol based and therefore much less dangerous.
[Neil McAllister]

Brush pens:

[Initial data and suggestion to include - Conrad Wong]

These are similar in behaviour to other colour markers - i.e., they have fading problems and should be considered ephemeral. Further, they are not known for producing initially solid blacks.

Some manufacturers are now making brush-pens which actually have tiny brushes at the tip, rather than a simple modified felt tip. These can possibly include pigmented inks, and would therefore last quite a bit longer. Sakura and Pentel both make dye-based brush-pens of this type, and - for dye pens - they hold up fairly well. Micron is apparently also shipping a brush-pen of this type which uses the same micropigmented ink that their technical pens do, and _that_ one will be of genuinely long life.
[Victor Wren; Neil McAllister]

Black brush ink:

All "india" ink-based inks should be durable. I've never heard otherwise. In fact, most brush inks will be more durable than most pen inks, given the above commentary on delivery systems; you _can_ deliver a durable pigment with a brush. I've been using Higgins Black Magic, but you can shop around; again, any india ink should do.

It is also possible to find pens which can be used to apply india inks; the traditional dip pen should handle most kinds of inks. Virtually all engineering pens should be able to do this as well.
[R'ykandar Korra'ti, Dave Bell]

I've also had FW and Kohinoor 3085-F recommended; I'm told it is easier to apply a thin line with FW than it is with Higgins Black Magic.
[Data from Victor Wren]

Pen-style brushes, preloaded:

[by Conrad Wong]

There are some pen-style brushes. Japanese stores may sell them; they will have reservoirs inside. Many brushes contain a special transparent liquid which turns black on a special paper. Artists will want to look for brushes that work on 'regular' paper. Watch whether it's a sable tip or a synthetic tip; the synthetic tips are stiffer, the sable tips are very soft and, consequently, can be harder to control. (They can also be necessary to avoid splatter on very rough surfaces - but this is a technique rather than durability issue.)

Colour brush ink:

[by Araiguma]

Depends on the ink, whether dye-based or pigment-based. I wouldn't hold my breath; it's usually dye. Darker reds and blues _tend_ to be more lightfast. Yellows are the worst, oranges and greens aren't far behind, _very_ loosely speaking.

A lot of artists' media these days has lightfastness ratings on the packaging. If that's not available, it's always worth asking the store staff.

On the good side, however, is that there is a new line put out by Higgins which is pigment-based - they refer to them as "fadeproof." FW also has a pigment-based (acrylic-based, actually) line. Some of FW's are relatively opaque, so watch out for that if that's not what you want.

Graphite (grey/black pencil):

Extremely durable if appropriately maintained. The only problems are ruboff and smearing. Protect the piece from direct sunlight and direct contact and you should be fine. Workable spray fixative will solve most of the ruboff and smearing problems, but these, too, bring other durability issues into play. (So far, I have had no problems with higher-quality spray fixatives.)
[R'ykandar Korra'ti; Conrad Wong]

Also recommended: "I've found the crystal fixative (non-workable) to be better for preventing smudging. To stop smudging with workable fixative (which is primarily intended for special techniques with pastel, not for archival use) takes an extremely heavy coating, which alters the contrast of the pencils."
[Victor Wren]


[by Araiguma]

Charcoal, like graphite, is elemental carbon and immune to color change or degradation. It poses a more serious problem in other areas, though, as the only thing holding the charcoal on the paper is friction. As such, it is very vulnerable to static electricity, if not fixed. And I'm highly dubious about spray-can fixatives, since the ones intended for the general public (i.e. not museum and conservation professionals) are "mystery fixatives in mystery solvents" - unknown longevity, stability, and safety for both the artist and the artwork.

Colour pencil:

So far, so good. I haven't had any fade problems with any of my colour pencil works. The delivery system is bonded with the pigment, so there's no limitation imposed that way. Stay with the better brands; I'm sure the K-mart school supply section store brand will have the cheapest (and least durable) pigment available. I primarily use Prismacolour markers, which are highly rated.
[Additional by Araiguma]

They do, as a class, tend to be a lot more stable than markers, if only because the carrier (wax) doesn't volatilize very much over time, and carry pigment off with it. Prismacolors give lightfastness ratings for the various colors. Of course, take manufacturers' ratings with a grain of salt; see the References section below for details.

Chalk pastel:

[by Araiguma]

Ones with natural pigments are pretty stable, ones with synthetic pigments are anybody's guess.

Oil Pastel:

Again, so far, so good. Oil pastels I've done have held up wonderfully, even in suboptimal conditions. The only problem with this medium that I've found is the ease with which it smears and rubs.

Hint: _never_ have the work in contact with _anything_ but air. If you frame it, use a matte. If you don't, it'll rub off.
[Additional by Araiguma; added bits by Victor Wren]

Problems: They never really dry, and the oil in them can bleed out into the paper. And if they're really gunked on thickly, the weight can actually distort the paper they're on. This is a medium that's really best on surfaces other than paper. However, a proper coat of gesso can make a stiff piece of illustration board suitable.


[Suggestion to add by Araiguma]

Classically pigment in an egg binder, these days it's "loud stuff of dubious origin and composition." It cracks and peels at the slightest flexing or fluxing in relative humidity. I've used it for a couple of temporary projects, and definitely would not recommend it for anything intended to be preserved. Even when new, it flakes; and worse - at least, the brand I used - "dusted," with some colours dusting off on touch.

For classical tempera, see "egg tempera," below.
[R'ykandar Korra'ti, Araiguma]

Egg Tempera:

The "real stuff," Classical Tempera, still available commercially, but often expensive. It will _always_ be listed as "egg tempera." Egg tempera artists often, in their quest for the perfect medium, will go so far as to make their own. Assuming proper pigment materials have been chosen, the result is an extremely durable paint, rivaled in this field only by high-quality oils. (Doing it by hand is also cheaper.)


Watercolours are generally considered the most ephemeral of the paint media, on average. This has to do with many people making watercolours use poor quality pigments and/or dyes in place of the higher quality materials, and not the media itself, but the end result is essentially the same from the artist's standpoint. Windsor and Newton claims solid durability, and I believe rates durability by colour.

Warning: be prepared to pay for durability; I remember that the stable watercolours cost about twice as much as other brands. And as always, take manufacturers' ratings with a grain of salt; see the 1eferences section. If all the colours are the same price, that's a sure sign that corners are being cut somewhere. Further, watch out for anything that lables itself a "hue;" that's marketing-speak for "approximated colour via an unknown method."
[R'ykandar Korra'ti, Araiguma, Neil McAllister]

Acrylic and oil paints:

Oil paints, on average, tend to be slightly more durable than acrylic paints. This will vary by brand, and by colour within a brand; student-grade paints will generally be less durable than professional or fine-arts lines, obviously. It is much harder to make a really bad choice in these media, however, than in markers, where it is very difficult to make a _good_ choice.

Note that any use of oil paints on canvas or illustration board will cause the board or canvas to dissolve unless the canvas or board is first prepped with a material called gesso.

Transparent liquid acrylics:

[Suggestion to add by]

I know very little about these, but have been told that have held up well to some artists' preliminary sunlightfastness testing.

Photocopier toner, dry:

[Suggestion to add by Hanno Foest]

Most dry toners are elemental carbon combined with some binding agent to allow the carbon to be bound with the paper. This method, in almost all cases, is heat.

The toner colour itself is stable. Unfortunately, the binder is not always so, and will often become brittle and flaky with age. Further, toner binding is particularly sensitive to heat, as anyone who has left a photocopy in a looseleaf binder exposed to the sun or a heat vent; the toner will transfer off the paper and onto whatever else it may happen to be touching. Humidity and outright moisture will cause the same sorts of effects. Laserprinted material may be more resistant to this sort of effect, as laserprinters often use higher fusing temperatures than photocopiers.

I've also been told that some toners will sometimes contain significant amounts of impurities. The impact of these impurities will depend upon their exact composition, and would be impossible to predict in advance.

For more commentary on photocopiers, see below, under "print paper."

Drawing Paper

Let me rant again about paper and backing (some of my favourite subjects :-) )...

Many artists will go out of their way to use a solid, high-quality, durable pigment for their work - and will then proceed to paint or draw on anything they find lying around. Where durability issues are concerned, however, paper is of prime importance. This is due to the acid content found in most papers, leading to paper discolouration, pigment discolouration, and even breakup of the paper.

Fortunately, this is a recognized problem, and you can purchase paper which has been pH neutralized. This paper will sometimes be referred to as "acid free," and sometimes "pH neutral." If it doesn't say, assume it has _not_ been pH neutralized. Strathmore bristol is a favourite paper for many artists.

It may also be worth your time to check even paper which declares itself pH neutral, as some companies have been caught shipping high- acid paper as "pH neutral." Testing can be done in a crude, but cheap and easy, way by using a pH testing pen, available for three or four dollars from multiple suppliers. Likewise, stay away from the cheapest papers; some which are indeed "acid free" may, if short- grained (like deacidified newsprint), retain a great deal of lignin, and be accordingly short-lived.

Your _very_ best bet would be a paper that's not just pH neutral, but which is actually buffered with alkaline salts to offset future degradation. The paper should have a high rag/cotton or alpha cellulose content; longer fibers, less of the lignin and hemicelloloses that contribute to acidity in paper.

Genuine Bristol paper is 100% cotton rag, with now wood fibre. If it contains wood, it will say "pine tree Bristol." [Victor Wren] 100% cotton rag is not acidic, and contains no lignin.

As a side comment, let me rant about hemp prohibition. Hemp, the non-psychoactive portion of the plant which produces marijuana, produces a _naturally_ pH neutral paper which is of significantly higher durability than any wood pulp paper. It would also be cheaper in mass production, and be more suited towards making really large pieces of illustrative paper. And thanks to the longer fibre length, it's noticeably more recyclable than wood-pulp paper. Yet another example of the stupidity of the drug war. End of polemic.

Drawing books containing pH neutral paper only cost a few dollars more than drawing books with regular high-acid paper. Buy them. Even if you're just planning on doodling in it, spend the extra three bucks. That way, if you come out with something you decide you really like and want to keep, you've got a good chance of doing so.

Of course, not all high-acid papers are equally bad. Newsprint is, of course, the least durable, and is marketed as such. It's great for temporary purposes - say, throwing together a couple of composition sketches, or warming up before figure drawing - but just remember that it won't last. Butcher paper - just as cheap, nicer to work on - has the same caveats.

Print Paper

First off: I will almost never buy anything done in any way on a photocopy for more than $4. In the US, the paper is almost guaranteed to be high-acid rot-o-rama material which will be turning brown inside five years. Apparently, this is less likely to be the case in parts of Europe; a German correspondent has tested all of his recent photocopies and found them all to be on acid-free paper, despite no efforts on his part to ensure that this was the case.

Colour copiers have different requirements, and as a result, colour photocopier paper is generally pH neutral in the US. But check to be sure.

Other than that, the same basic rules listed above apply here, too. Paper suppliers are generally pretty good at labelling pH neutral papers as "acid free," so if you're going to make prints, all you have to do is ask for the right materials. Even in low-volume print runs, this won't add much to your cost.

Mattes and Backing Board

These are also often overlooked, even by people who take the care to use pH neutral paper and lasting pigments. Mattes are less damaging, since they have limited contact with the piece in question - but you can still get a nasty brown bleed coming off the edge of a high-acid matte. This is because the acid in the matte can leak into the paper it touches.

This is especially true of those evil mattes with the "acid-free" face and back with pure junk cardboard filler in between. The acid migrates out of the mat bevels, producing mat burn, and the "acid-free" face and back can only endure for a little while before they become acidic, too. [Araiguma]

The backing board matters more, since it's in contact with all of your piece. I will often find that people have used cardboard as backing for their artwork. This is a very bad idea, as cardboard is _extremely_ high-acid - and fibrous, and likely to shed - and _will_ degrade the life of your piece if you don't isolate it from the art paper. If you must use cardboard, separate it from the artwork by a layer (or two!) of pH neutral paper, or, if you can find it, pH basic paper, buffered to pH 8.5 or so.

This is even more important when it comes to photographs, as the acids in the cardboard will also alter the chemicals making the colours in the print.

Most pre-made mattes I've found have, much to my shock, been pH neutral. Most backing board material, on the other hand, has _not_. And it costs half again as much as standard backing material, too. Foo.

One very important point to note about matte board is that, even those which are pH neutral are _not_ coloured with a lightfast medium! They are exclusively ink. Those who like to do little sidebar illustrations on the matte board should keep this in mind. [Victor Wren]

One topic often overlooked is adhering artwork to acid-free mattes and backing. There are several ways to do this. Scotch tape is, of course, right out, and brown masking tape is even worse - it is high acid, and the adhesive will crystalize and transfer onto the paper, leaving ugly stains. But if you want to use adhesive tapes, acid-free high-quality matting tapes are available, as is a white artist's tape made by Scotch (Tape #285). [White tape and data on masking tape by Victor Wren]

I prefer to avoid the issue of adhesive-against-artwork entirely, and use a securing method suggested to me by another artist which avoids the issue entirely; making art holders out of acid-free paper, and taping _those_ to the backing board. This is very easy:

It should look something like this (ASCII art never to scale):

         /\         /\
        /_/_       _\_\
       | / /-------\ \ |
      /|T1/         \T2|\
     / / /    art    \ \ \
     \/|/             \|\/
        |             |
        |             |
     /\|\             /|/\
     \ \ \           / / /
      \|T3\         /T4|/
        \ \         / /
         \/         \/

T1-T4 are triangles of acid-free paper, held down with acid-free mounting tape. The tape should be OVER the triangles, and should never touch the artwork itself.

The Buyer's Perspective

When I consider buying a piece, I look for a note from the artist which explicitly states that pH neutral paper was used. If I don't find that, I adjust my willingness to buy accordingly. If I do buy, I immediately take apart the matte and re-back the original with pH neutral paper. (This stuff is cheap, not exotic. You can buy a sketchbook full of it for $7.)

If the picture is backed with cardboard, that's another materials strike; cardboard is very high-acid material. That, too, always gets ripped out and replaced. The more of this I have to do, the more the picture ends up costing me before all is said and done.

I have some originals work by a particular artist hanging in my bedroom. It needed to be ripped apart, layered in back with pH neutral paper, and backed with new material. I love this artist's work, but I wonder whether much of it'll be around in 10 years, given some of the materials used; the paper is short-fibre and (I suspect) high acid, and was backed it with cardboard. I think _my_ copies will last, because I've worked to insure it. But most people aren't going to know to do this.

My _requests_ to all creators and sellers of artwork are:

  1. Know your materials. Use stuff that'll last. I'll know, and pay more for it. This includes your paper. Acid-free illustration board tends to cost a couple of dollars more, I know, but I'll make that trade. Consider all markers to be ephemeral unless proven otherwise, and always remember: photocopies flake, doubly so when damp, triply so when hot.
  2. Don't forget that mattes and backing boards are (typically) paper too, and affect the things they touch. Most pre-made mattes I've seen _have_ been acid-free (much to my shock!) but most backing material is _not_. Be warned, and act appropriately. If you don't know when buying, _ask_. And if you make prints, make them on good paper. (I've seen people get everything but that right...) It won't cost you that much more per print (I've priced it for some of my own material :-) ) and will be worth it in five years.
  3. Show me that you knew what you were doing when you prepped the work. Tell me that the paper, backing, mattes are pH neutral. If they _aren't_, tell me that, too; I'll correct where I can. Give me clues about the permanence of the media you used - I'll presume the answers are bad, if you don't speak up.

People have been becoming more aware about these things. Slowly.

Reference Materials

The following books have been strongly recommended as reference texts on materials durability.
The Artist's Handbook - Ralph Mayer
"A constant companion... unfortunately, it becomes ever more dated as new pigments, materials and products enter the marketplace."
The World's Best Watercolour Paints - by Colin Wilcox, published by Northern Lights.
The most important independent test set. "Shock. Dismay. Sense of betrayal. And a whole bunch of very expensive so-called artist grade watercolour tubes into the garbage. It seems that with everyone taking the makers' word, had bothered to try the lightfastness tests for themselves..." "Reading the Wilcox book caused me to radically change my palette."

A Summary

For my own work, I use low-cost pH neutral paper (see the above $7) for most work, or pH neutral illustration board for anything I expect to want to do on something like that and keep. When I sell, I either back with pH neutral board (about 50% more expensive than the typical) or, if I can't (rare circumstances), I isolate the print/drawing/whatever from the bad backing board with layers of pH neutral paper. And, of course, I use pH neutral mattes.

A note from Neil McAllister: "If you have to slip pH neutral paper between a picture and its backing, I'd look for a material called Glassine. It's a pH neutral separator paper that's got almost a wax-paper surface. That should be sufficient to keep a picture away from a bad backing, rather than layers of a more porous acid-free drawing paper.

When drawing, I only use markers I have reason to believe are stable, if I intend to keep the work for more than a couple of months. I've yet to find a thick, black, controllable marker which I trust to stay, so I use brush and a permanent well ink instead. For colours, I use the aforementioned Letraset/Pantone markers or coloured pencil, and hope the Pantones live up to their billing. I've had it recommended that I use watercolours instead, as even cheap pigment-based watercolours will be better than markers.

For submissions, on the other hand - they're not supposed to last more than a couple of months, so I use whatever's handy that looks good. Photocopies touched up with Sharpie pens are my favourite, backed with a cardboard mailer. :-) (The reason I bring this up: remember when you should spend the money to make it last, and when you don't need to care. :-) )

Note that none of this costs me any more time or effort than using high-acid materials. Once you've found a source for all the things you need, you just remember to go there and buy the right things, rather than going someplace else and buying the wrong things. It does cost a little more, but only a very little, and it's a price I'm willing to pay.

Do these things, and your buyers will appreciate it eventually, even if they don't know about it at time of purchase.

When buying, I check what the artist has used, and correct where applicable. If the backing material is cardboard or not acid free, I replace it, or stick in a layer of pH neutral paper. Same with the matte. If I don't know about the paper, I stick extra layers of acid free paper behind it, to absorb as much acid from the original paper as I can. I then frame; this is more expensive, but limits air circulation (which helps delay acid problems) and also can block some UV light damage. If a piece is worth it or will be hanging in a high-light area, I'll get special clear plastic designed to block all UV, and use that instead of glass in the frame. _Never_ use shrink-wrap for this purpose; it won't help, and will leak gasses which are actively bad for the piece. Also, never hang in direct sunlight; anything that can go wrong will go wrong more quickly when exposed to the sun, even if you've put plastic or glass in front of it.

Neil McAllister notes again: "Glass with a UV-filtering coating is also available," and is almost always cheaper than plastic.

Do these things, and the artwork you buy will last much longer than it would have otherwise, and at relatively little additional cost. It'll also look better in the long run. Oh; if you can't frame, do everything up to that, including the layer of glass or plastic in front, and then clip (not tape!) it together. That'll save you some money and get you most of the preservation benefits of a frame.

One final note: I don't pretend that this is a be-all or end-all treatment on this subject. Reams of academic papers published on the subject will, in fact, easily demonstrate otherwise. However, I believe it to be a basically accurate set of rules which, if followed, will allow a much longer lifespan for artwork, at minimal additional cost and hassle.

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