| Author | Message | ||
  Maidensmith New member Username: Maidensmith Post Number: 1 Registered: 8-2006 |
I have had the exact same problem with Winsor Greeen BS. I can use it unless it's in a covered palette. If I put it in a covered palette it has a white "stuff" on top of it when I next use it. It has lost a spot in my Cheap Joe's palette. I was wondering if it is something other than mold. | ||
Anonymous Painter |
I bought some empty half-pans and made my own replacements for those in the Cotman Field Kit, from my W/N artists' quality tube paints. In each pan, I mixed a very tiny amount of glycerine and honey with the pigment, using a toothpick. I have had no mold problem except with the Winsor green (PG 7) half-pan. It so happens that this particular pan sits in the upper part of the kit (where no pan sits in the kit as sold), so perhaps it is more vulnerable to moisture here. If I close the kit with this pan even slightly wet, it will develop mold again. (This doesn't seem to happen with the other pans.) No matter how often I wash off this mold, wipe the surface pigment away with cotton swabs, etc. the mold will come back and cover the surface, if it's left even slightly damp. Sunlight (ultraviolet radiation) should kill mold. Letting the paint dry should avoid the problem. In the studio I use a plastic covered palette, letting the paint dry out, and have not had any mold problems, even with that same tube of PG 7. So my theory is if mold spores do just happen to enter the pigment at any point, that pigment will develop mold whenever its surface is left moist again. Iow, I suspect it's a random thing -- mold spores floating in the air get into pigment occasionally. Once this happens, any moisture allows the mold to grow again from the spores. As I recall, however, I also used a touch more glycerine or honey with this pigment -- it was certainly the last of my home-made half-pans to dry, by more than 24 hours. There may just be too much honey in this formulation, offering sustenance to the mold.... These days, as soon as I get back home, I always open my Field Kit and let the paint dry thoroughly. (Just as I normally wash my brushes thoroughly, if I've been in the field.) This seems to avoid the problem. :) | ||
Donna |
I've had mold on reds such as alizerin and permanent rose. I have never had it on yellows. I live in the north where we have central heating and dry conditions. I wonder if there is mold in the circulating air of the home. We do have basements. Another thought is that I may fill my rinse bucket and if I don't use it I let it sit and use it days later. Could it have mold in it and I have inoculated my paints? I have never met another artist who has this problem. Many of them actually keep a damp sponge in the palette and have no problem. I'm dealing with it. Thanks again, for all the help......... | ||
A.N |
M.Graham paints utilize honey. Honey is a natural mold inhibitor. Might be worth a try. | ||
Rekha |
Suzy, are these paints from the same manufacturer? Gum arabic can be a good medium for bacterial and fungal growth. It might be worth taking it up with the manufacturer. | ||
Suzy |
I live in FL,(Humidity is a way of life...) I pack my pallette around with me to all my outdoor shows, leave it in the booth over night in all sorts of dreadful conditions. I pack it up wet, and don't open it again until the next weekend at the next show and that pallete has never had mold in it. My pallette at home, which is open in my air conditioned studio, that dries out everyday, and is technically in "ideal" conditons grows mold. It only grows mold however in the the following colours... Cobalt Blue Ultramarine Blue, Burnt Sienna Burnt Umber Thinking that maybe ther was mold spore stuck in those wells, I dug out the paint, cleaned it good, wiped it out with alcohal, then wiped it down with a tad of pure Organic Lavendar oil (..An anti-fugal)I threw away my old tubes (All WN) and bought new ones..(American Journey)) and it still grew back in those colors I don't get it. | ||
A.N. |
Actually the paint is altered, but perhaps not the pigment, since the paint is the mixture of pigment gum arabic and additives like dextrin. If I add alcohol to watecolour paint (let's say w&n Sap Green out of the tube), the chemistry is thereby altered. The only point of contention is "is this a bad thing?" | ||
Rekha |
A.N., as far as I know paint chemistry is not altered. In fact a lot of extractions of organic paints is done using fairly strong solvents like acetone, alcohol etc | ||
A.N. |
Rekha-- I think what I was getting at is that if you use alcohol to create texture you are in effect distorting the paint's appearance and altering the chemistry of the original product. That is what I meant by destroying the integrity (meaning the way it was meant to be out of the tube). I will concede though that I know next to nothing about this, just applying what I thought was common sense. But if people paint with alcohol... | ||
Grace |
Ever hear of the Whiskey Painters of America? Use whiskey to paint minatures, and imbibe while do so. Seem to also have a propensity for stool sitting. Man who shows at the same gallery as I do sells quite a bit of his very lovely mini whiskey paintings. | ||
John Preston |
19th century British watercolorist Paul Sandby is supposed to have used gin in his rinse water. I've never read of any curatorial problems associated with his work and the published reproductions of his work don't appear unusual in any way. | ||
Rekha |
You are not clear, AN, but what you mean by integrity; any references? | ||
A.N. |
A.N.-- When alcohol creates texture it does so by destroying the integrity of the paint. The fact that alcohol distorts the nature of the paint is what I meant by destroying its integrity. One would assume that a substance which "creates texture" is doing something to the paint that water does not. | ||
Donna |
Thank you for all the responses. I looked up the handprint site - thank you, Marie. I'm going to try some of the suggestions, probably starting with refrigerating my palette. I cleaned my palette again and found mold also in the Windsor Green. I remember that it was in the Alizerin in the past and I use that with W. Green to make black. I will try some alcohol in my water rinse too. I might have just got something going in my paints and brushes and will have to be extra careful until it is gone. | ||
Rekha |
A.N., could you provide some references to the statement you made about 'alcohol will destroy the integrity of the paint'. Which integrity does it destroy? I ask because a lot of watercolourists use it to create texture without any noticeable change in the painting. | ||
Rekha |
I suggested alcohol and perhaps didn't clarify; at the end of washing of your palette rinse in alcohol and then let dry. Does that make sense? If you are using plastic palettes bleach will harden the plastic; I would test a small area before going ahead to dip the palette in bleach | ||
A.N. |
Sun kills mold. Mold thrives in humidity and darkness and on a medium (in this case gum arabic). Best solution is to always use fresh paint if you are in a high humidity area. Alcohol will destroy the integrity of the paint. The standard treatment for mold is sodium hypochlorite (bleach) but don't introduce that into your paint. Mold is highly toxic--the spores can cause all sorts of health problems. Do a search to confirm this. The comment "I couldn't bear to wash away all that paint" reveals a shortsightedness. Better to use fresh paint that expose yourself to health risks and your painting to decomposition through mold. | ||
John Preston |
I had that problem too. In my case the mold was in the tube and reappeared whenever I set that color out. Rekha's alcohol suggestion worked for me once it was on the palette but I eventually got rid of that tube. Don't know how it got in the tube or why other colors didn't get moldy. | ||
Rekha |
You could let the paints dry but that sometimes, not necessarily consistently for the same paint, I find it difficult to suspend the paint back in water. I tend to discard these because in these specific pots it is possible that the gum arabic (binder) has hardened. I have ordered a pot of binder to resuspend the paint to determine whether this is true. | ||
Rekha |
I have had this with two-three of the many paints I keep in air-tight plastic pots so I am not in a position to establish a definitive cause. I think Listerine has a pH of 3.8, that is, it is quite acid. Perhaps giving a final rinse of alcohol to the palette before putting paint on the palette may be an idea. It may also be an idea just to use filtered water. | ||
marie |
I have never had trouble with mold. Frankly, I am surprised that I haven't; I live in a humid climate, and don't clean my palette regularly. Handprint has lots of suggestions, including keeping your palette in the refrigerator and adding a bit of Listerine to your paints. He has more suggestions at http://www.handprint.com/HP/WCL/tech14.html | ||
Donna |
I occasionally have mold form on the tops of the paints in my palette and if I don't see it I get a string of slime on my brush that clues me in. It is usually just one or two. Currently, I have W&N Q Rose and Grumbacher student grade Permanent Green effected. I got a new palette and changed all the paint (it killed me to wash all that paint away). Someone said maybe it was heat so I changed my set-up so the palette wouldn't sit in the sun. I've left the top off to let the paints dry between sessions. Any suggestions? |
