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Edradour
11-25-2014, 04:42 AM
Hello,
I have been aware for some time that there are questions about the durability of zinc white in oil paint.

Yesterday, I recieved a link (click) (http://www.naturalpigments.com/art-supply-education/zinc-white-oil-paint-color/) from Natural Pigments summarising a research project into zinc white in oil paint. In summary the article says "For the time being, [zinc white] should only be used in [oil] paint where the objective is not permanence."

As an artist, working in oil, are there alternatives to titanium white?
It is a pigment I do use, but there are times when it is either too opaque or too blue for the task in hand.

I live in Europe (UK), where, for regulatory reasons, lead based paints are practically unobainable.

Gigalot
11-25-2014, 04:59 AM
Hello,
I have been aware for some time that there are questions about the durability of zinc white in oil paint.

Yesterday, I recieved a link (click) (http://www.naturalpigments.com/art-supply-education/zinc-white-oil-paint-color/) from Natural Pigments summarising a research project into zinc white in oil paint. In summary the article says "For the time being, [zinc white] should only be used in [oil] paint where the objective is not permanence."

As an artist, working in oil, are there alternatives to titanium white?
It is a pigment I do use, but there are times when it is either too opaque or too blue for the task in hand.

I live in Europe (UK), where, for regulatory reasons, lead based paints are practically unobainable.

The role of Zinc White is not SCIENTIFICALLY studied. It is true.

Zinc White was widely used by Preraphaelite brotherhood artists. Their paintings are in a very good conditions. Zinc can't be replaced in paints, unless you are using alot of Lead White in paint, in mixtures, in gesso, in medium. Personally I don't have an alternative to ZInc. I used it much and will try to use even more, in increased amounts. Zinc white paint is always lean. I do not add solvent into it. I think, that properties of Zinc-Titanium White paints are just perfect. Permalba Original was tested many times by Weber and by artists. It works and it don't yellows much.

Do not bear it in mind, Robert. Oil paint is worst material, but nothing is better than oil painting! (Probably, Sir Winston Churchill can also agreed :) )
I can read so many well coordinated attacks to all painting materials we can use in art :) And the targets are Canvases, Alkyds, Damar, Solvents, Acrylic Gesso, Rabbit Skin Glue, Refined Linseed oil, Safflower oil, Ivory Black, Maroger Medium and many more! :clap: :confused:

"summarising a research project into zinc white in oil paint" - chickens laugh! :D
A bit oxidized, and after, heated linseed oil, show very good adhesive properties and good durability. It can be a specially, good medium to mix with Zinc White.

Mythrill
11-25-2014, 06:07 AM
Hello,
I have been aware for some time that there are questions about the durability of zinc white in oil paint.

Yesterday, I recieved a link (click) (http://www.naturalpigments.com/art-supply-education/zinc-white-oil-paint-color/) from Natural Pigments summarising a research project into zinc white in oil paint. In summary the article says "For the time being, [zinc white] should only be used in [oil] paint where the objective is not permanence."

As an artist, working in oil, are there alternatives to titanium white?
It is a pigment I do use, but there are times when it is either too opaque or too blue for the task in hand.

I live in Europe (UK), where, for regulatory reasons, lead based paints are practically unobainable.

Hi, Hidratour!

I don't know why, exactly, but paintings with an egg tempera ground show little to no damage to Zinc White (PW 4) over time. I suspect painting over egg emulsion gives oil better adhesion to the painting.

From what I understand from Natural pigments, sometimes Zinc White turns into soap. I don't know if you can completely stop it, but to slow this saponification in oil paint, one interesting idea would be to isolate the layers containing Zinc White from the rest of the painting. A simple technique would be rubbing a very thin layer of linseed oil over a surface, allowing it to dry, painting over it, and waiting again.

Another interesting idea would be to avoid Zinc White altogether. Just use Titanium White (PW 6) and a medium with colorless pigment, like oleogel, in different proportions to impart transparency to your painting.

Gigalot
11-25-2014, 06:18 AM
Another interesting idea would be to avoid Zinc White altogether. Just use Titanium White (PW 6) and a medium with colorless pigment, like oleogel, in different proportions to impart transparency to your painting.
:) My own idea is somewhat equal. A quart of housepaint Alkyd white can do the same job. But this strategy is not completely compatible with my working technique. Oil painting is made from 70% of White paint. Housepaint do not have such a great working properties to replace all of my whites. :confused:

A quart of house paint Alkyd + one tube of prohibited, bought on Black market, Lead White treasure can be effective as a replacement to Zinc White pigment. Use house paint for everything except glazing and some delicate mixing in which Lead White can do it's job. :lol:
A big Paint Manufacturers do their paints for industry and exterior usage, so paint has more than enough durability and weatherfastness to use on artists canvases. The industrial Alkyd can stay 30 years on a lamppost on the street. Will stay on my canvas as well.

Mythrill
11-25-2014, 06:48 AM
:) My own idea is somewhat equal. A quart of housepaint Alkyd white can do the same job. But this strategy is not completely compatible with my working technique. Oil painting is made from 70% of White paint. Housepaint do not have such a great working properties to replace all of my whites. :confused:

Hi, Giga!

I would be concerned about weatherfastness when using house paint. Won't it delaminate from the canvas?

Gigalot
11-25-2014, 07:03 AM
Hi, Giga!

I would be concerned about weatherfastness when using house paint. Won't it delaminate from the canvas?
No, it stay well, I tried. :wink2: And it do not show beading effect. No beading! The other advantage - used on top, oil paint gives a pleasant gloss and dries faster. I guess, siccatives can penetrate from housepaint into oil paint layer.
I have 1,5 years experience to do that. However, I used Zinc White, not a Lead White over housepaint enamel. ;)
BTW, Fast Matte Alkyd Titanium White can be used over acrylic primer to prevent Zincs to contact with gesso layer.

mariemarie
11-25-2014, 08:36 AM
FastMatte Alkyd Titanium White can be used over acrylic primer to prevent Zincs to contact with gesso layer.
Good morning Gigalot,

I don't want to digress too much. Do you refer to Gamblin FastMatte Alkyd Titanium White? If so, it did very bad in Jonathan Linton's tests.

Do you still recommend using it?

(I can't find the link to the experiment this morning. I need another espresso. Sorry!)

Bradicus
11-25-2014, 10:07 AM
http://blog.jonathanlinton.com/2010/05/white-test-5-years-in-making.html

Here is link. Test was done with, what looks to be, almost no standards or consistancey. I dont automatically discount the results. But looking at the test shows oil running down the board on some, sample sizes are vastly different and so on. Think he squeezed the paint out of tube onto board and put outside.

I would suggest you do your own tests if conconcerned, maybe being a bit more precise. Using those whites which you might use or like.

Brad

Gigalot
11-25-2014, 10:22 AM
Good morning Gigalot,

I don't want to digress too much. Do you refer to Gamblin FastMatte Alkyd Titanium White? If so, it did very bad in Jonathan Linton's tests.

Do you still recommend using it?

(I can't find the link to the experiment this morning. I need another espresso. Sorry!)
Have a nice day, Marie!
Sure, FastMatte Alkyd will be yellowish even if you didn't seen the test! It do not have Zinc White, which is good bleaching agent and it has Cobalt Siccative , which is darkening agent into paint formulation. Yeah, this paint will turn yellow! :)
But I have a reason to use this paint as a layer on top of acrylic gesso. Alkyd show a good result in acrylic ground delamination test in which Zinc White additive can be problematic. It makes a barrier. To paint over it, I think, Permalba Original is a good choice. It highly tested much time by Weber and many artists. Nobody have seen how it cracks. It is low yellowing and cheap white paint. Safe to use on Fastmatte Titanium White. How you find this idea? Permalba original as a basic white on Fastmatte Alkyd underpainting?

Bradicus
11-25-2014, 11:50 AM
I will add that Gamblin offers "flake white replacement" which is only titanium white.

llawrence
11-25-2014, 12:39 PM
I put more stock in that test than others here do. (The 28 year (!) strength and flexibility test, not the Linton.) George O'Hanlon certainly knows what he is doing regarding art materials, and I don't believe he is prone to hysterics. As far as I'm concerned, if he is still sharing that information, then there is something to it.

I think artists should use whatever materials they feel they need to best express themselves, and not spend too much time worrying about illusory 'permanence'. Having said that, I don't see any reason to doubt this study - at least, no more than any other.

Gigalot
11-25-2014, 12:50 PM
I will add that Gamblin offers "flake white replacement" which is only titanium white.
They said "Slower drying time". Just interesting "How much" slower?
Almost everybody have seen the test in which pure Titanium White pigment in raw cold-pressed linseed oil do not dried even after 17 years. It became even more weak over time!
Just interesting, if Zinc White drier is not added to this paint and Lead White drier is also not added (I trust Gamblin, they said no lead was added!) when which siccative gives to this paint "Flake White" pigment properties? And "how much" siccative they are using?

mariemarie
11-25-2014, 01:01 PM
(...) Yeah, this paint will turn yellow! :) (...) To paint over it, I think, Permalba Original is a good choice. It highly tested much time by Weber and many artists. Nobody have seen how it cracks. It is low yellowing and cheap white paint. Safe to use on Fastmatte Titanium White. How you find this idea? Permalba original as a basic white on Fastmatte Alkyd underpainting? Thank you, Gigalot. I have adopted the «Duchess of Alba» upon your recommendation and your idea obviously make sense: I will use my Gamblin FastMatte along but I really would prefer lead white by itself! ...or just an oil primer.

I also could try the «Flake Replacement» out of curiosity, Brad. And thanks for the link!

Gigalot
11-25-2014, 01:16 PM
...or just an oil primer.

This is the best idea! :heart:

Bradicus
11-25-2014, 02:39 PM
I put more stock in that test than others here do. (The 28 year (!) strength and flexibility test, not the Linton.) George O'Hanlon certainly knows what he is doing regarding art materials, and I don't believe he is prone to hysterics. As far as I'm concerned, if he is still sharing that information, then there is something to it.

I think artists should use whatever materials they feel they need to best express themselves, and not spend too much time worrying about illusory 'permanence'. Having said that, I don't see any reason to doubt this study - at least, no more than any other.
I agree, now they have released this report Questions must be asked.
These are smart people doing good research.
But so many have 20,30,50+ yr old paintings. No issues. Titanium/zinc white has been a staple for what 70 years? I cant make the two facts connect.
I can connect Zinc paint by itself cracking, Bill (WFMartin) posted an example just this month of a fish he painted twenty( I think) years ago, that had cracks at the glazing.
Any reputable paint peddler will say zinc by itself is brittle.

Hummmmm,
Brad

Gigalot
11-26-2014, 05:52 AM
Bill (WFMartin) posted an example just this month of a fish he painted twenty( I think) years ago, that had cracks at the glazing.
Any reputable paint peddler will say zinc by itself is brittle.

I asked Bill about his painting. ;) :) He answered, that cracked area has yellow color, painted with many layers, mostly with Yellow Ochre. White paint was used in a tiny amount. If so, Zinc White is not a cause of those cracks.

Looking to a Zinc White paint areas on my own paintings, I can say that Zinc White can crack. But, it will be the last "cracked" paint among other paints. :lol:
I thing, strong mechanical impact in winter period (in hot summer days my oil paint is more flexible) can harm my six years or older paintings. I will protect the back side of my paintings with polyethylene foam shield.

JamieWG
11-26-2014, 01:03 PM
I put more stock in that test than others here do. (The 28 year (!) strength and flexibility test, not the Linton.)

Me too. I don't use zinc white and steer clear of most mixtures that contain it. Maybe I'm playing it safer than is necessary, but it's what I'm comfortable with for now. I try not to be overly-reactive to information. As Gigalot has so wisely stated, we can end up not oil painting at all if we listen to everything that everybody says! I try to take reasonable precautions, and not using zinc, from my own perspective, is one of them. This is fueled by the fact that I never used it much anyway, so I don't really miss it.

Gigalot
11-26-2014, 01:22 PM
Me too. I don't use zinc white and steer clear of most mixtures that contain it. Maybe I'm playing it safer than is necessary, but it's what I'm comfortable with for now. I try not to be overly-reactive to information. As Gigalot has so wisely stated, we can end up not oil painting at all if we listen to everything that everybody says! I try to take reasonable precautions, and not using zinc, from my own perspective, is one of them. This is fueled by the fact that I never used it much anyway, so I don't really miss it.
Too many paints contains Zinc White, which is not documented as additive. Adding Zinc to their whites, manufacturers just say they use "a very small amount" which is not considered as a "pigment" addition, and do not needs to be published. But, when I dig deeper, I find 3% of not documented Zinc in "Titanium White", 2% ZInc in "Fast Drying White", 2,5% in "Flake White Hue" and so on.. It can be find in several "Yellow Ochre" in many organic "Cadmium Yellow/Red Hue", even in "Cadmium Yellow", "Cadmium Red". What is the reason to add Zinc to paint formulation? Just paint dries better with Zinc or it is completely non-drying without Zinc addition.
They do right thing. They can't add Lead to their paints due to it's toxicity, therefore they do Zinc. And most people are thinking, that they "do not needs to use Zinc White" :angel: :D Zinc is already present in their paints!

JamieWG
11-26-2014, 02:02 PM
Too many paints contains Zinc White, which is not documented as additive. Adding Zinc to their whites, manufacturers just say they use "a very small amount" which is not considered as a "pigment" addition, and do not needs to be published. But, when I dig deeper, I find 3% of not documented Zinc in "Titanium White", 2% ZInc in "Fast Drying White", 2,5% in "Flake White Hue" and so on.. It can be find in several "Yellow Ochre" in many organic "Cadmium Yellow/Red Hue", even in "Cadmium Yellow", "Cadmium Red". What is the reason to add Zinc to paint formulation? Just paint dries better with Zinc or it is completely non-drying without Zinc addition.
They do right thing. They can't add Lead to their paints due to it's toxicity, therefore they do Zinc. And most people are thinking, that they "do not needs to use Zinc White" :angel: :D Zinc is already present in their paints!

I know that it is present and that unless I'm going to be making all my own paints (which I do not plan to do!), I will have that small percentage of zinc in my paint. I cut out as much as I can without making myself crazy. It's the best I can do and still have a "reasonable" approach, from my perspective. Hopefully that small amount is okay, since I don't plan to start driving myself nuts over this anytime soon. ;)

Bradicus
11-26-2014, 02:17 PM
I know that it is present and that unless I'm going to be making all my own paints (which I do not plan to do!), I will have that small percentage of zinc in my paint. I cut out as much as I can without making myself crazy. It's the best I can do and still have a "reasonable" approach, from my perspective. Hopefully that small amount is okay, since I don't plan to start driving myself nuts over this anytime soon. ;)
Jamie and Gigalot, what white do you use?
Brad

Gigalot
11-26-2014, 02:20 PM
I know that it is present and that unless I'm going to be making all my own paints (which I do not plan to do!), I will have that small percentage of zinc in my paint. I cut out as much as I can without making myself crazy. It's the best I can do and still have a "reasonable" approach, from my perspective. Hopefully that small amount is okay, since I don't plan to start driving myself nuts over this anytime soon. ;)
:thumbsup:
I am not sure why people so much are worrying about it.:confused: I do not pay much attention on this Zinc. But every day they are posted Zinc, Zinc, evil Zinc crack, delaminate, decompose. Probably, they are in a strong panic...;)

Gigalot
11-26-2014, 02:31 PM
Jamie and Gigalot, what white do you use?
Brad
:D Zinc White and Zinc-Titanium White I use most of all. And sometimes, highly pigmented Titanium. It gives "flat", "lipstick" color in mixtures. It has a great hiding power!
But, in deep underground of my paint box, I have a rare tube of Lead-Zinc White! It was never opened!

JamieWG
11-26-2014, 03:28 PM
Brad, I only use titanium white. I use Winsor Newton Titanium White, and also use Utrecht, Lukas Sorte, Rembrandt, and others. I don't see a reason to break the bank and buy an expensive brand for titanium white. :) As long as it has a good pigment load and is ground in safflower oil, I'm happy. But I might have a new favorite.... I recently asked RGH Artist Oils to send me a stiffer, more highly pigmented titanium white than their normal version. I am loving that paint, and it's very reasonably priced. They did not charge me extra for it either!

My favorite is to take a good titanium white made with safflower oil, and mix it about 2:1 with Griffin Alkyd. That gives me a white that handles more like a traditional titanium white, but dries much faster. I mix up batches of it and then tube it myself. Lately I'm not using that though, mostly due to the fact that I am premixing my palette and storing it, mixing more as I run out of mixed colors. The alkyd would cause the white and all of my tints to dry out.

Bradicus
11-26-2014, 04:00 PM
It gives "flat", "lipstick" color in mixtures. It has a great hiding power!...
and here is statement from previous thread on reds...
?..BTW, lipstick red is Naphthol!...

Colour expert, foresooth! Everyone, EVERYone knows lipstick red is pr209.

I use Grumbacher titanium white which( insert panic and despair ) has zinc.

I like it alot. Tube is very bendy, so I should be ok, right?

Cheers,
Brad

Gigalot
11-26-2014, 05:59 PM
Colour expert, foresooth! Everyone, EVERYone knows lipstick red is pr209.

I use Grumbacher titanium white which( insert panic and despair ) has zinc.

I like it alot. Tube is very bendy, so I should be ok, right?

Cheers,
Brad

Lipstick Red is Naphthol PR4:
http://www.artiscreation.com/red.html#PR4
It is first described by Sid! :lol:

Mythrill
11-26-2014, 08:53 PM
Lipstick Red is Naphthol PR4:
http://www.artiscreation.com/red.html#PR4
It is first described by Sid! :lol:

For lipsticks, we also have PR112 and PR 57.1. However, PR112 is too expensive for lipsticks, since it only stays on one's face for around a day, and, when stored, it's mostly in the dark.

Bradicus
11-26-2014, 10:27 PM
For lipsticks, we also have PR112 and PR 57.1. However, PR112 is too expensive for lipsticks, since it only stays on one's face for around a day, and, when stored, it's mostly in the dark.
Oh for crying out loud... PR4 and 112? Really?

And 57.1? That fads so fast she would never make to the ball before her lips would be black.
Can we get serious here now please.
The Sky is blue and Lipstick red is 209. Thank you.



Jamie, I agree, I too like a low cost white. The soft form from grumbacher works great for me. And its like 6-8 bucks for 200ml. In fact I think grumbacher is a under rated paint and is perfect for UMB, sap green, etc.

Pretty cool RHG made you a special batch. I have never used them.

Happy Thanksgiving Everyone, I am grateful for my friends here at WC!

Cheers,
Brad

opainter
11-26-2014, 11:16 PM
Here's a tip to all you lipstick lovers: Add a little Titanium White (right out of the tube!) to your lipstick and you've got instant added sunblock protection!

Happy Thanksgiving!

JamieWG
11-27-2014, 12:21 AM
Jamie, I agree, I too like a low cost white. The soft form from grumbacher works great for me. And its like 6-8 bucks for 200ml. In fact I think grumbacher is a under rated paint and is perfect for UMB, sap green, etc.

Pretty cool RHG made you a special batch. I have never used them.

Happy Thanksgiving Everyone, I am grateful for my friends here at WC!

Cheers,
Brad

Grumbacher paint is too soft for me, and the cadmiums too weak. But some folks swear by them and love 'em to bits, and it's nice to have a paint out there at that in between price range. They have some colors that I'm okay with too.

For the record, I don't think RGH made the white batch for me, though they might have. I was telling a friend of mine that the RGH Titanium White was too soft and weak for my liking, and she told me that she asks them to make it stiffer and more concentrated for her. So that's what I did. They may make both kinds regularly now, or maybe they had some left from her batch, or maybe they did make it up fresh. But however they did it, I got it! :D

Bradicus
11-27-2014, 01:28 AM
I asked Bill about his painting. ;) :) He answered, that cracked area has yellow color, painted with many layers, mostly with Yellow Ochre. White paint was used in a tiny amount. If so, Zinc White is not a cause of those cracks...
Giga, I went back and you are right, WFMartin stated that the cracks could have, and was suspected, of coming from high medium usage.
Not from glazing with zinc, but from glazing with high ratio medium.
I got my glazing stories mixed up.
Was a really good fish painting.

Jamie, Grumbacher being soft is true, but I like that usually.
I dont use there cads much, more MGraham and BlueRidge.
I dont love GR to bits for sure, but the work for me in the "any brand" group like FUB. There are several brands that would sub fine.

Opainter, is that true?
And, I dont think I will be doing that! Ha.

opainter
11-27-2014, 02:01 AM
Opainter, is that true?
And, I dont think I will be doing that! Ha.

Interestingly enough, sunbathers do put sunblock lotion that contains white pigment on their noses. One product, for example, is called Zinka. On its website it has a list of ingredients that include both zinc oxide and titanium dioxide (no lead). So yes, this is true. About lipstick, I don't really know, but probably not.

JamieWG
11-27-2014, 01:14 PM
I just saw this (http://www.naturalpigments.com/art-supply-education/zinc-white-oil-paint-color/), which was published in October. So I think from this point forward, I'll only buy titanium white that is all titanium white. (There's a list if you scroll down the article.)

Gigalot
11-27-2014, 02:58 PM
I just saw this (http://www.naturalpigments.com/art-supply-education/zinc-white-oil-paint-color/), which was published in October. So I think from this point forward, I'll only buy titanium white that is all titanium white. (There's a list if you scroll down the article.)

Just old, negative, anti-zinc information. No one word about paint film polymer structures. I know or read ten times more. This is just an upper-water part of a giant iceberg.
The role of Zinc is not studied well, but the author's transform several facts on a negative notes to a 100% negative conclusion. And ignore Titanium troubles. Lead white troubles. Lets remove all those pigments from our palettes. Oh, yes, you are sure, Titanium White is OK just because this article do not discredited it too much? :) Oh, yes, strong photodestruction catalyst, TiO2, which can do crack water molecules to OH radicals, will have long term "archival" properties in a pure form. Zinc White is specially added to a Titanium to protect organic molecules against photodestruction.

Mythrill
11-27-2014, 07:00 PM
Well, Zinc White (PW 4) can be added to Titanium White (PW 6) without you knowing, as Natural Pigments says in Giga's link:


What the table does not reveal is the zinc that may be included in white oil colors by manufacturers not conforming to the standard. ASTM does not enforce its voluntary standards.

If Zinc White (PW 4) mixed to Titanium White (PW 6) seems a troubling idea, you can always get pure Titanium White, a respirator (so you won't breathe the dust), and make your own paint. Considering we use Titanium White a lot in acrylics and in oils, buying and making your own paint could actually save a lot of money.

opainter
11-27-2014, 08:56 PM
Well, Zinc White (PW 4) can be added to Titanium White (PW 6) without you knowing, as Natural Pigments says.

Because I don't know which paints from which manufacturers Natural Pigments is alluding to here, they might be sub-artist-quality paints, paints from less-than-reputable manufacturers, or paints that are from reputable manufacturers who happen to not label their paints with the pigments they use. I would also be leery of manufacturers who shift their production to Asia in order to save money, because who knows what quality controls (if any) or oversight exists. Otherwise, if one buys artist-quality paint from a reputable manufacturer who lists their pigments on their tubes and jars, I would really doubt that you would encounter this situation.

Gigalot
11-28-2014, 05:32 AM
Reputable oil paints makes reputable cracks with pleasant symmetry and deepness. Other, less reputable manufacturers produce paints with non-traditional crack orientation. Chinese paints gives random Chinese cracks.
Some of their paints do not crack, but I don't know which exact. :D
Unfortunally, reputation do not helps in chemistry. :clear:

Paint is Titanic, Zinc is iceberg. Everybody knows, that Titanic sunk affected by iceberg. Wrong suggestion! Titanic sunk affected by water around it. And this water penetrated there due to a worst structure of ship.

People can try to use Weber Permalba White Classic. It is produced since 1920 years and do not yellows, do not cracks! :angel:

Mythrill
11-28-2014, 06:50 AM
Reputable oil paints makes reputable cracks with pleasant symmetry and deepness. Other, less reputable manufacturers produce paints with non-traditional crack orientation. Chinese paints gives random Chinese cracks.
Some of their paints do not crack, but I don't know which exact. :D
Unfortunally, reputation do not helps in chemistry. :clear:

Paint is Titanic, Zinc is iceberg. Everybody knows, that Titanic sunk affected by iceberg. Wrong suggestion! Titanic sunk affected by water around it. And this water penetrated there due to a worst structure of ship.

People can try to use Weber Permalba White Classic. It is produced since 1920 years and do not yellows, do not cracks! :angel:
But Permalba White is made of Titanium White (PW6) and Zinc White (PW4), isn't it?

Gigalot
11-28-2014, 07:26 AM
But Permalba White is made of Titanium White (PW6) and Zinc White (PW4), isn't it?
Yes. But it was highly tested.

I miss my chief and people from chemistry laboratory I worked long time ago :crying: Probably he is not alive now. I know what he can say at this point. "Ask them only one question, Why did Pre Raphaelite painted Zinc White do not crack? If they dont answer you or kidding you with bla answers - do not trust them, they just know nothing there. Do your own undependent investigation if you like"

Bradicus
11-28-2014, 01:38 PM
Reputable oil paints makes reputable cracks with pleasant symmetry and deepness. Other, less reputable manufacturers produce paints with non-traditional crack orientation. Chinese paints gives random Chinese cracks...
:lol: :lol: :lol: So funny!
Now I know why Chinese paints are perfered in abstract.
I am with Giga so far. I reread the paper.

There are many things to think about and it is very well researched.
I agree with the overall idea, but not sure what they got, I will get.
I think keeping zinc low in usage would be a good idea though.

But a few qualifiers:
First, the show apainting that cracked from 1956.
But the painting had been rolled! Im no expert, but dont roll a 60 year old painting.
Next they discuss zinc white snapping like glass, but glass is tough, and I dont bend my painting, unless trying to fit them in the garbage can.
There are other things, too, but I digress.
I think a great solution is to paint on panel if very concerned.
Or if you are like me, and perfer canvas to panel(to stiff), then back your canvas with foam-board when its done.
Anyway, I think its good to discuss. I think many just put there head in the sand and say NOT TRUE! But as said by others, painting is a series of compromises, and I like to know the questions at least.

Wait till they are transporting my painting to off world "Museum of Earthly Painters" on Mars colony station. Then we are going to find out about zero-g and how cerulean and veridian should not be together! "Big study done...What can be won??"

Brad
PS that last bit rhymes

Gigalot
11-28-2014, 03:04 PM
Wait till they are transporting my painting to off world "Museum of Earthly Painters" on Mars colony station.

Do noy use heavy panels, Brad!

I will paint "The Fifty-three Stations of the Martian Tōkaidō road" :D signed "for use on Mars only, no heavy metals, Pb-Cd free, light weight oil paint on hemp canvas". "Girl with Martian fruit" - Griffin aerospace alkyd on polyethilene foamed hemp canvas, 16x20 . :lol:

Bradicus
11-28-2014, 04:21 PM
Do noy use heavy panels, Brad!...
My paintings will be worth the jet fuel Giga, well worth!
Nothing but Lead white, cads, and impasto!

... I will paint "The Fifty-three Stations of the Martian Tōkaidō road" :D signed "for use on Mars only, no heavy metals, Pb-Cd free, light weight oil paint on hemp canvas". "Girl with Martian fruit" - Griffin aerospace alkyd on polyethilene foamed hemp canvas, 16x20 . :lol:
Best part is, I think you are only half joking!

B.

karenlee
11-29-2014, 10:24 AM
Gigalot wrote:
Too many paints contains Zinc White, which is not documented as additive. Adding Zinc to their whites, manufacturers just say they use "a very small amount" which is not considered as a "pigment" addition, and do not needs to be published. But, when I dig deeper, I find 3% of not documented Zinc in "Titanium White", 2% ZInc in "Fast Drying White", 2,5% in "Flake White Hue" and so on.. It can be find in several "Yellow Ochre" in many organic "Cadmium Yellow/Red Hue", even in "Cadmium Yellow", "Cadmium Red".


I am curious about which paint brands you are referring to, and how you dug this info up? If you could take the time to provide those details to us-- thank you!

Gigalot
11-30-2014, 04:11 AM
I am curious about which paint brands you are referring to, and how you dug this info up? If you could take the time to provide those details to us-- thank you!

Unfortunately, I didn't found this information again. There are a lot of pages in many articles. I don't pay much attention on Zinc White when I read them. I remembered this 3% and 2% Zinc White digits, just because it was strangely for me, why Fast Drying White paint has less Zinc additive in it, while Titanium White has more. Sure, this brand is reputable brand. But I only can remember 3%, 2% and 2,5% - nothing more. I just forget information, which is not important for me. My Zinc do not show me any cracks on my paintings. :D I am looking for vegetable oil polymers synthesis and structure and printing industry oils.
But, searching this info again, I found that: Zinc White has an effective bleaching properties in White Paint, when it's concentration is above 20%-30% into paint formulation. Therefore, paint with whitest formula and non-yellowing properties, has, actually, a lot of Zinc White added there.
And I fixed an article where I found this, so people can go and read it:
Maor_Yonah_200809_MAC.pdf

llawrence
11-30-2014, 11:08 AM
First, the show apainting that cracked from 1956.
But the painting had been rolled! Im no expert, but dont roll a 60 year old painting.
Next they discuss zinc white snapping like glass, but glass is tough, and I dont bend my painting, unless trying to fit them in the garbage can.Well, we don't stick our paintings out in the blazing sun for months either, but that's exactly how they test for lightfastness. Doesn't invalidate those lightfastness tests, I think.

The point is to stress the materials badly over a short period of time to find out what might happen in more normal conditions over a long time.
I think a great solution is to paint on panel if very concerned.:thumbsup: Yep, zinc white on panel is a great solution.

Another is to mix zinc white with lead white. Lead white is the opposite of zinc, and tends to retain its strength and flexibility over time - as well as lending some of its properties to other paints used, even across layers! Zinc white, in its turn, may help lead white retain its opacity a little better. Good for everyone! :clap:

Gigalot
11-30-2014, 11:57 AM
Another is to mix zinc white with lead white. Lead white is the opposite of zinc, and tends to retain its strength and flexibility over time - as well as lending some of its properties to other paints used, even across layers! Zinc white, in its turn, may help lead white retain its opacity a little better. Good for everyone! :clap:
This mixture has better whiteness and it's flexibility is not bad. But it has less adhesive properties. Nothing to be wrong, but it might be better to avoid to use it directly on smooth acrylic gesso. A little, adhesive, heated linseed oil couch can help. Or, a very thin layer of Titanium White under it.

Bradicus
11-30-2014, 06:54 PM
Well, we don't stick our paintings out in the blazing sun for months either, but that's exactly how they test for lightfastness. Doesn't invalidate those lightfastness tests, I think...
Agreed, and I believe that was my overall tone.
My first statement was to both state it was well researched, and that I agree with thier overall idea. I look to more of the details.

If lightfast testing was 28 years in the sun, I would discount it.
That not relevant to me as a test. Interesting, but beyond what I expect.
To that point, I ask what was done to 'test' zinc.
I wouldnt roll an old painting. I think this does show the brittleness.
Now, would it crack from the expansion of hot cold from night and day?
Dont know, but thats of interest to me.

I want to know where the line is to see if I feel comfortable on which ever side I am on. The people whom did the study are obviously super smart and I look forward to more research.

That was my point.
Cheers,
Brad

llawrence
11-30-2014, 07:59 PM
Okay, Brad - no offense meant. I like to discuss, is all. Cheers!

Bradicus
11-30-2014, 08:14 PM
Okay, Brad - no offense meant. I like to discuss, is all. Cheers!
Non taken at all.
I just want to be clear that I wasnt discounting out of hand.
Thought maybe I came across that way.
I enjoy the discussion aswell, a potentially serious issue.
Cheers to you,
Brad

Gigalot
12-01-2014, 08:06 AM
This paint do not have Zinc White in it. I guess, it has Kaolin, Stearate, Titanium White pigment in safflower oil binder. Even a small amount of Zinc White paint, mixed into it, can increase drying speed and oil film hardness of this paint significantly. That means no Zinc was added there by manufacturers. It dries to a soft, slightly yellow, highly adhesive paint film. So, people of China are very kind gives this paint to me at a low price! :)

Having this paint, I can control Zinc content into my whites. No Zinc in contact with gesso and high Zinc in glaze for example. The other "Zinc-free" white is housepaint. It has Titanium White and fillers into Alkyd binder.