Chemistry of Paint & Pigments

[Turtle]

Unfortunately, that shot has turned completely blue! ;)

I tried the "putting them in the dark" approach, but it hasn't worked, so I guess I'm stuck with just a dark blue piece of paper. :(

Oh well. I'm hoping to try out a few more shots this winter (whenever I get some free time ---- which isn't something I have very much of these days).

 

As for the Potomac, I will certainly try, but it doesn't freeze over all that often. :cup:

 

Well, maybe try the opposite & put it in a sunny spot? Maybe the image will reemerge?;) At least you got a scan of it. It's very haunting and has a Currier & Ive's-esque quality I find appealing. Here's wishing for a white Christmas! :) Santa always knows when you've been bahahaaaahd. :eek:

[Mercedes Benzene]

Well, maybe try the opposite & put it in a sunny spot? Maybe the image will reemerge?;) At least you got a scan of it. It's very haunting and has a Currier & Ive's-esque quality I find appealing. Here's wishing for a white Christmas! :) Santa always knows when you've been bahahaaaahd. ;)

 

I will certainly try a sunny spot tomorrow.

And I hope you have a wonderful holiday yourself!

[Turtle]

I will certainly try a sunny spot tomorrow.

And I hope you have a wonderful holiday yourself!

 

erhm...merry christmas? :wave:

 

so anyway, i thought of you & this thread earlier this week while reading up on some flowers as i tried to id them. in addition to getting to the names- i must know the names!! :)- i enjoy reading about a plants ethnobotanical uses and occasionally i see an entry mentioning a use of a plant as a dye. naturally when i get onto an thing i know little about, i'm like, what's up with that!? :lol:

 

so, what is up with pigments in plants? i have the obligatory wiki that i just perused, but i'm just as interested in what you et al may have experience-with/knowledge-of/interest-in the chemistry of pigments in plants. say tree! :lol: :Alien:

 

Biological pigment - Wikipedia, the free encyclopedia

[Turtle]

i finally plunged in with a dye experiment. :doh: i had split up a green red-alder log for a wood project and put the resulting boards in a plastic bucket with water to minimize splitting while the wood cured. after a week i noticed the water was deeply colored and recalling from my botanical studies that alder has a long history as a dye, i filtered off the deep orange-yellow liquor.

 

taking a crocheted cotton wash-rag i received as a gift but could never bring myself to use on dishes (:doh:), i weighted it with a rock in a galvanized bucket holding the dye. a day or so of that & nothing was sticking so i decided to boil it.

 

not wanting to set the kitchen on fire or make it stink again i opted to avoid the comotion and set up my propane camp stove. got out the cast iron camp-pot, poured in some dye, dropped in the knit rag, & boiled it on up. within a shiort time the dye was coal black and the rag taking on a deep gray. wow!

 

wondering if it was the iron or just heating the dye caused the change, i poured some more raw dye in a stainless pot & tossed in a piece of canvas (also cotton in case i need to mention that scientifically speaking. ;) ) boiled the snot out of it & no change to black. the fabric did take on a yellowish hue however and the dye deepend in color as it boiled down.

 

i have a virgin wash-rag (i got a pair) and will make comparison photos of each dye sample and their un-dyed counterparts tomorrow when they are dry & i have good natural light.

 

in the mean time, here's a montage of my experiment & for you chemists, why did the dye turn black in the iron pot? did the dye being in the galvanized bucket play a role in either outcome?

 

that's the way it is. . . . . . . :hyper:

 

[Turtle]

the piece of canvas dyed in the stainless steel pot did not take the dye so no photo of nothing to see for you. :evil: :P the crocheted rag however took and held a nice medium gray after rinsing & drying. :) chemists? why did the iron-pot dye go black & how do i get the yellow-orange dye to stick? enquiring minds want to know. :) :) :shrug:

 

[modest]

I would guess (but, please don't take my word for this) that you got some iron acetate. Does wood liquor have vinegar? If so, then i'd be pretty sure that's what happened. To test the hypothesis you could wash the pot and repeat the experiment with vinegar. If you get a similar result then iron acetate it is.

 

~modest

 

EDIT:

 

After googling a bit, I'm sure that's what happened. Wood distills pyroligneous acid which reacted with the iron to make iron(III) acetate (ferric acetate). It is used as a dye:

 

http://www.answers.com/topic/iron-acetate-liquor

 

Well done Mr.T

[freeztar]

Turtle, I think you would be interested in this link:

 

A practical treatise on dying woolen ... - Google Books

 

I skimmed down through it a bit and it seems to deal mostly with indigo, but there's some "chymistry" in there and it might eventually talk about alder dyes but I haven't got that far yet.

 

I do see it recommends cutting the alder in April or May and peeling the bark right away then letting it dry.

[Turtle]

I would guess (but, please don't take my word for this) that you got some iron acetate. Does wood liquor have vinegar? If so, then i'd be pretty sure that's what happened. To test the hypothesis you could wash the pot and repeat the experiment with vinegar. If you get a similar result then iron acetate it is.

 

~modest

 

EDIT:

 

After googling a bit, I'm sure that's what happened. Wood distills pyroligneous acid which reacted with the iron to make iron(III) acetate (ferric acetate). It is used as a dye:

 

iron acetate liquor: Definition from Answers.com

 

Well done Mr.T

 

fascinating! following those sources they have pyroligneous acid as a by-product of charcoal production, wheras i cold-soaked wood & bark to get my starting liquor. i see the term 'mordant' which is new to me and looking further i see it's a chemical that makes the dye 'stick'. i may need some of that to get the yellow-orange alder dye to stick. :)

 

Turtle, I think you would be interested in this link:

 

A practical treatise on dying woolen ... - Google Books

 

I skimmed down through it a bit and it seems to deal mostly with indigo, but there's some "chymistry" in there and it might eventually talk about alder dyes but I haven't got that far yet.

 

I do see it recommends cutting the alder in April or May and peeling the bark right away then letting it dry.

 

roger. will have a read.

 

i got my alder log when i found it laying in the gutter of the road by my house. fell off some fire-wood-cutter's truck no doubt. i found some etnobotanical stuff on alder dyes today, though there is a lot of mythology tied up with alder along those lines and going back thousands of years.

 

Alder

Italian witches used to mix the sap from the Alder tree with that of the madder plant, a Eurasian plant (Rubia tinctorum of the family Rubiaceae) to produce red dyes. These were then used to colour ribbons, cords and sashes for use in magick and ritual. Ritual bags made of wool and dyed red have been highly prized by Italian witches since classical times. Also, in Italy, the wood of the Alder was used to light the fires for the spring festival at Ostara.

 

 

In dyeing, the Alder’s bark is used as a foundation for blacks with the addition of copperas. Alone, it dyes woollens a reddish colour (Aldine Red). The Laplanders chew it and dye leathern garments with their saliva. The young shoots of the Alder dye yellow, and with a little copper a yellowish-grey, which is useful in the half-tints and shadows of flesh in tapestry. The shoots cut in March will dye cinnamon, and if dried and powdered produce a tawny shade. The fresh wood yields a pinkish-fawn dye and the catkins a green dye. The leaves have been used in tanning leather. They are also clammy and, if spread in a room, are said to catch fleas on their sticky glutinous surface.

 

as i have red alder here, Alnus rubra, it seems the locals figured out how to get different colors from different layers of the bark.

http://plants.usda.gov/plantguide/doc/cs_alru2.doc

Various layers of the red alder bark yield red, red-brown, brown, orange, and yellow dyes (Moerman1998). The various colors from the bark were used to color baskets, hides, moccasins, quills, and hair. The native Americans of the Pacific Northwest extracted a red dye from the inner bark, which was used to dye fishnets. Oregon tribes used the innerbark to make a reddish-brown dye for basket decorations (Murphey 1959). Yellow dye made from red alder catkins was used to color quills.

 

thanks guys. :) well thens, got me sum readin' ta do and i'm dyin' to get to it. :doh:

[modest]

fascinating! following those sources they have pyroligneous acid as a by-product of charcoal production, wheras i cold-soaked wood & bark to get my starting liquor.

 

Here's another:

 

Fun with Vinegar-and-Iron Dye Stains

 

It seems your liquor had a fair amount of acetic acid in the mix... and your pot a slight propensity toward oxidizing.

 

~modest

[Turtle]

Here's another:

 

Fun with Vinegar-and-Iron Dye Stains

 

It seems your liquor had a fair amount of acetic acid in the mix... and your pot a slight propensity toward oxidizing.

 

~modest

 

roger. i had sliced off much of the bark in the original soak because it's the cured wood i'm really after. i gathered the bark up though yesterday and i'm letting it dry for later use.

 

my cast-iron dutch oven came un-seasoned and as i was unfamiliar with seasoning cast iron i likely did a half-assed job of it. :doh: it is entirely black now though, to the level of the liquor i had in it and i wonder if this in itself is a protective coating against rust as is oil & heat seasoning or perhaps even like bluing of steel?

 

i have a bunch of black-eyed susans in bloom right now & i read that the petals make a yellow dye. prolly gotta try it! :) also i have a pint saved of the black dye and i think i may boil it down and try it as a drawing ink. . . . . . . . .

[modest]

i have a pint saved of the black dye and i think i may boil it down and try it as a drawing ink. :) . . . . . . . .

 

Good call on the ink.

 

The Spatula: a magazine for pharmacists - Google Books

 

It would be similar to iron gall ink.

 

~modest

[Turtle]

Good call on the ink.

 

The Spatula: a magazine for pharmacists - Google Books

 

It would be similar to iron gall ink.

 

~modest

 

i have a recipe for that; plenty of galls in lechtenberg too.

 

so, looks like i need to "mordant" my cotton with alum first before dyeing to get the yellows & greens. :) think i can get away with baking powder? Baking powder - Wikipedia, the free encyclopedia

 

About Mordants

Mordant literally means "to bite". The mordant is the chemical link that fixes the dye to a substrate by combining with the dye pigment to form an insoluble compound. This chemical can be a salt or a hydroxide of aluminum or chromium. And, of course, a variety of substrates can be mordanted and dyed: textiles, leather, flowers, and wood. ...

 

anyway, here's where i got so far today with the Rubeckia. . . . .

 

[modest]

so, looks like i need to "mordant" my cotton with alum first before dyeing to get the yellows & greens. :) think i can get away with baking powder?

 

I know nothing about dying, but I'd say it's certainly worth a try. You say the cotton didn't take the yellow / orange at all? You could probably soak the cotton in an oversaturated solution of baking powder then take it out and let it dry before putting it in the dye. Yeah, I'd say it's definitely worth a try.

 

You've got me interested in this topic

 

~modest

[freeztar]

Mordants! Aha!

 

Here's some neat info I found regarding mordants for natural dyes:

 

Alum: (Aluminum Potassium Sulfate)

This is the most widely used mordant. Be careful not to use too much with wool, otherwise you will get a sticky feeling that doesn't come out.

 

Copper: (Copper Sulfate)

This mordant is used to bring out the greens in dyes. It will also darken the dye colors, similar to using tin, but is less harsh.

 

*Chrome: (Potassium Dichromate)

Chrome brightens dye colors and is more commonly used with wool and mohair than with any other fiber.

 

Extremely toxic. Chrome should not be inhaled and gloves should be worn while working with chrome. Left over mordant water should be disposed of at a chemical waste disposal site and treated as hazardous waste.

 

Iron: (Ferrous Sulfate)

Dulls and darkens dye colours. Using too much will make the fiber brittle.

 

...

 

More at the following link: Natural Dyes, Mordants, and Helpful Tips

 

I wonder what the Native Americans in WA used. :)

 

You've got me interested in this topic.

 

Turtle has a knack for that, eh?

[Turtle]

I know nothing about dying, but I'd say it's certainly worth a try. You say the cotton didn't take the yellow / orange at all? You could probably soak the cotton in an oversaturated solution of baking powder then take it out and let it dry before putting it in the dye. Yeah, I'd say it's definitely worth a try.

 

You've got me interested in this topic :)

 

~modest

 

nope; virtually no residual color even after boiling in the dye.

done & done on the first mordant experiment. 2 tablespoons baking powder & 16 fl oz water soaking an 8"x10" swatch of canvas.

 

my interest was so keen that i tasted a few drops of the Rudbekia liquor; very bitter! :doh: it took an ipa to wash out the taste. :eek2:

 

I wonder what the Native Americans in WA used. [as mordants]

 

stale urine. :eek:

 

and other natural things. >>

 

Natural Dyeing of Textiles - Technical Information Online - Practical Answers

...Traditionally, mordants were found in nature. Wood ash or stale urine may have been used as an alkali mordant, and acids could be found in acidic fruits or rhubarb leaves (which contain oxalic acid), for example.

 

oxalic acid eh!? can we say Oxalis suksdorfii!?? aint that somethin' how nature provides and chaos favors the prepared imagination?

 

now to see if cotton prefers an alkali mordant or an acidic one. :)

eat, drink, and be merry for tomorrow i dye. :)

[freeztar]

oxalic acid eh!? can we say Oxalis suksdorfii!?? aint that somethin' how nature provides and chaos favors the prepared imagination?

 

Indeed. :)

 

Forget the oxalis suksdorfii, ( ) the Western skunk cabbage (Lysichiton americanus) might not be flowering now, but its leaves are perfect oxalic acid carriers.

[Turtle]

Indeed. :(

 

Forget the oxalis suksdorfii, ( :D ) the Western skunk cabbage (Lysichiton americanus) might not be flowering now, but its leaves are perfect oxalic acid carriers. ;)

 

:shrug: yeah, i only mentioned suksdorfii because hey, you can never mention suksdorfii too often and it's growing in my yard. :) there is skunk cabbage at lechtenberg and some other Oxalis species as well, & i will now have new reasons to get stuff there when i go. this time of year the skunk cabbage leaves here have died back, having done their job replenishing the bulb after the blooming cycle and there will be no new growth 'till next spring.

 

i have my baking soda mordanted canvas drying & will give the dyeing a whirl later today. i plan to cut 4 test strips and try cold & hot dyeing with the Rudbekia dye and the alder dye i prepared in the stainless pot. i'm on it like saffron on a monk's robe. ;)