Tung oil or China wood oil

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Q-Lee

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Does any one know if it's possible to use Tung oil or China wood oil for soap making?
I normally use this for making natural wood wax/wood polish then started thinking and wondering a bit....
o_O
 
Interesting question - can you find any breakdown of values for tung?

'Chemical characteristics acid value mg KOH/g max. 8 saponification value mg KOH/g 189 - 198 iodine value (Wijs) g I2/100g min. 158 moisture, impurities & volatile matter % max. 0,25 unsaponifiable matter % max. 0,75 gelling time minutes max. 13,5
Fatty acid composition Palmitic acid (C16) % max. 5,5 Oleic acid (C18:1) % max. 4 Linoleic acid (C18:2) % max. 8,5 alpha-Eleostearic acid (C18:3) % min. 82'
https://www.castor-international.nl...printbare-versie-op-briefpapier-sjabloon).pdf

It seems it has the right type of values but silly me doesn't know enough to convert this to usable knowledge for you.
 
Does any one know if it's possible to use Tung oil or China wood oil for soap making?
I normally use this for making natural wood wax/wood polish then started thinking and wondering a bit....
o_O

Sounds scary to me! A high percentage of soaping oils are also food oils. The remainder are used in other body products, including lip balms (shea, cocoa, etc.) I would say that since Tung and/or China wood oils are not used in any body products or comestibles, using it for soap would not be safe or healthy.

I would expect residues such as from hexane and other processing steps, in addition to additives unsafe for human skin and biology. The manufacturing standards and legal requirements for non-food and non-human use products are greatly different, as well.

I didn't Google it at all -- this is just from my 44 year journey as a highly critical natural and organic consumer with extremely high standards.
 
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o_O
Interesting question - can you find any breakdown of values for tung?

'Chemical characteristics acid value mg KOH/g max. 8 saponification value mg KOH/g 189 - 198 iodine value (Wijs) g I2/100g min. 158 moisture, impurities & volatile matter % max. 0,25 unsaponifiable matter % max. 0,75 gelling time minutes max. 13,5
Fatty acid composition Palmitic acid (C16) % max. 5,5 Oleic acid (C18:1) % max. 4 Linoleic acid (C18:2) % max. 8,5 alpha-Eleostearic acid (C18:3) % min. 82'
https://www.castor-international.nl...printbare-versie-op-briefpapier-sjabloon).pdf

It seems it has the right type of values but silly me doesn't know enough to convert this to usable knowledge for you.

That's what I found too..
 
Sounds scary to me! A high percentage of soaping oils are also food oils. The remainder are used in other body products, including lip balms (shea, cocoa, etc.) I would say that since Tung and/or China wood oils are not used in any body products or comestibles, using it for soap would not be safe or healthy.

I would expect residues such as from hexane and other processing steps, in addition to additives unsafe for human skin and biology. The manufacturing standards and legal requirements for non-food and non-human use products are greatly different, as well.

I didn't Google it at all -- this is just from my 44 year journey as a highly critical natural and organic consumer with extremely high standards.

But he oil is from pressing seeds from the nut of the Tung tree (Vernicia fordii) so it's all natural. Further..pure Tung oil is considered safe to use on wooden surfaces that comes in contact with food and/or as a varnish on wooden children's toys.
Maybe it's not used in cosmetics because it tends to hardens upon exposure to air?
 
But he oil is from pressing seeds from the nut of the Tung tree (Vernicia fordii) so it's all natural. Further..pure Tung oil is considered safe to use on wooden surfaces that comes in contact with food and/or as a varnish on wooden children's toys.
Maybe it's not used in cosmetics because it tends to hardens upon exposure to air?

Tung Oil (otherwise known as Chinawood Oil) is FDA approved for use on surfaces that come in contact with food, but only in it's pure form (there's a lot of products labelled "tung oil" that have other ingredients to speed up polymerization, so you'd have to be fussy buying it for use on skin).

The main fatty acid (over 80%) in first press tung oil is Eleostearic acid, which is an interestingly shaped 18-carbon unsaturated fatty acid

I had a bit of a look around for you, and while other drying oils (such as linseed and walnut) are included in soaps in small amounts (they are prone to rancidity in large quantities), I was not able to find a tung oil soap (or a soap that used tung oil/chinawood oil in the soap), except for a patent from 1967, where they emulsified the tung oil with a small amount of vegetable soap (to make a skin cream). In that patent they talked about having to stop the alpha form of elostearic acid being converted to the insoluable beta form by exposure to light.

Your data sheet gives the SAP value for Tung oil as around 192 (I found one reference that gave 190-195 as the KSAP value, and your sheet has 189-198, so 192 is a good median). The NaSAP is KSAP divided by 1.403, which puts the Tung oil at about the same NaSAP value as Safflower oil (at about NaSAP 137).

The Iodine value is very high, at 163-173. What this tells you is that the oil would be better used at a small percentage of the total oils in your soap, rather than as a single oil soap, to avoid rancidity. Having said that, make a single oil soap anyway, just to test how long it lasts :)

I've never soaped this oil, but the final soap is likely to retain a strong scent, probably will be fairly soft (but try it, like I said, the molecule shape is odd and it might end up harder after a long cure). It also looks like this oil was used for medicinal purposes in the past.

In other words, it looks interesting and you could use Safflower as a very rough equivalent in the soap calc (that will give you a good average for the SAP value), but make sure you get a pure oil (that is not partially polymerized; preferably first cold-press/organic/wild harvest if you can get it, just to be sure).
 
Fig darling, you are amazing. I still wouldn't personally use it, but it seems a bit less scary now. ;)

ETA: I read the patent. At the first mention of "animal's skin" i said, oh well, maybe it's also animals, but toward the end, I read this:

"In another embodiment 70-85 parts by weight of raw tung oil, and 5-10 parts by weight of other vegetable oil (such as linseed, castor, olive, cottonseed oil) are added to 10-20 parts of an aqueous solution of vegetable oil soap, containing 7085% water.

The above ingredients are either vigorously mixed by stirring or heating or are run through a colloid mill or homogenizing machine for several minutes to produce a creamy and white emulsion. Use of a colloid mill or homogenizing machine decreases the size of the oils fat droplets, increases fluidity and facilitates rapid penetration into the animals skin."

This still sounds terribly yucky to me. I'll pass, thank you.
 
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It's classed as an irritant, can cause dermatitis, and people allergic to tree nuts can react to it. I wouldn't use it.

And folks.. all natural doesn't mean safe. Foxglove, strychnine, polio, lead and arsenic are all natural.
 
So far I've found plenty of warnings for tung products where the oil is blended with a solvent, such as naptha, for finishing applications, and for solvent extracted tung oil (which is more stable and will remain liquid after heating) and for the tree itself, which is toxic.

For every instance of the cold pressed oil, it's come up as non-hazardous, and the natural oil (when cold-pressed from the tung kernel) does not appear to be any more problematic than some of our common soaping oils.

It's classed as an irritant, can cause dermatitis, and people allergic to tree nuts can react to it. I wouldn't use it.

And folks.. all natural doesn't mean safe. Foxglove, strychnine, polio, lead and arsenic are all natural.

Hi paradisi, have you got a reference for this?
(It would be great to have more data on the natural tung kernal oil posted here.)
 
It's classed as an irritant, can cause dermatitis, and people allergic to tree nuts can react to it. I wouldn't use it.

And folks.. all natural doesn't mean safe. Foxglove, strychnine, polio, lead and arsenic are all natural.
You forgot Cobra Venom. :)
 
[QUOTE="SaltedFig, post: 756400, member: 22026"


Hi paradisi, have you got a reference for this?
(It would be great to have more data on the natural tung kernal oil posted here.)[/QUOTE]

A couple, but I'm unable to paste them for some reason. It's easy enough to find however... chemicalbook and tungoil.co.uk both turn up, amongst others, when one searches on "tung oil" dermatitis or "tung oil" allergic. It's hazardous to ingest, can cause dermatitis, etc.
And no, the things I'm mentioning are just the straight oil, not including solvents.

That kind of search is something I'd always do when investigating a new raw material or ingredient, at minimum.
 
A couple, but I'm unable to paste them for some reason. It's easy enough to find however... chemicalbook and tungoil.co.uk both turn up, amongst others, when one searches on "tung oil" dermatitis or "tung oil" allergic. It's hazardous to ingest, can cause dermatitis, etc.
And no, the things I'm mentioning are just the straight oil, not including solvents.

That kind of search is something I'd always do when investigating a new raw material or ingredient, at minimum.

Can you provide (type into a post) the name of the chemical manufacturer you found the hazardous information on, in the list on Chemicalbook?
(Your restriction might be post volume based, so it shouldn't be long before you can add a link directly).

On checking your list (instead of going to chemical manufacturers directly), I found the first Chinese supplier is giving a 404 (page not found), the second supplier states that is "contains no substances with occupational exposure limit values" (SigmaAldrich at 8.1, whom I'd already checked the SDS prior to writing my first post), the third supplier (Chinese) did not list Tung Oil, Chinawood oil or CAS 8001-20-5 (and requires a login), and I decided not to check the 4th, 5th and 6th suppliers (all Chinese).

The Tungoil.co.uk website contains similar information to the woodworking websites I checked, prior to writing in my post that it looks no more harmful than any other oils we use for soaping.
The Safety data on that particular website states that Tung Oil is a naturally occurring triglyceride vegetable oil with no hazardous ingredients. I've included it for completeness:
http://tungoil.co.uk/wp-content/uploads/2012/11/Tung-Oil-HS-2012.pdf

The two warnings I have seen for the natural Tung oil are that it is a slip hazard if spilt, and a fire hazard (releases carbon monoxide if burned). I have already noted that the tree itself is toxic, and that also includes the flesh and coating of the kernal (in the same way that the outer coating of the castor bean is a deadly toxin, we do not use the toxic parts).

Contact dermatitis is possible with any nut/kernal oil - if you are ruling out all nut and kernel oils on the basis that someone might be sensitive to nut oils, then yes, include this one as another kernel oil, however I do not (currently) see a reason to single out this this particular oil as being unsuitable for soaping with.
I am more than happy to change my mind if there is any evidence that the natural form of the oil (cold press) is any more harmful to skin than any other oils we use (such as walnut, sweet almond oil etc.).
 
The allergen part is a question for me. People with peanut allergies can eat peanut oil without a problem (or many can) because the oil is refined and the allergen that is present in the actual peanut is not in the oil. Looks like the FDA would not allow peanut oil to be label as an allergen because of this so one would assume dermatitis would be a separate issue and not related to peanut allergy. I wonder if the same is true for tree nut oils, where the oils are refined enough that the allergen is not present.

Also saying that tung oil is hazardous to ingest and therefore should not be made into soap doesn't make sense to me as a straight statement. Fragrance oils and many EO's should not be put directly on the skin and they can eat through certain materials in seconds. I would never dream of ingesting them but most of us do not hesitate to use them in soap. Some people use them in leave on products such as lotions and butters but I suspect drinking an FO would be highly unwise.
 
I should have read further into that patent, instead of stopping at the quote I posted last night.
The patent for using this with vegetable oil soap further stated:

"The emulsion of raw tung oil in an aqueous solution of vegetable oil soap product is useful as a
cleansing, dry skin preventing, skin conditioning, and hair grooming emulsified lotion or shampoo
for dogs and other animals.


"In addition it also aids in preventing and controlling various skin lesions and skin
ecto-parasites of dogs and other animals.
The oil emulsion in concentrated form may be
applied to the animals hair and skin as a lotion by thoroughly rubbing (massaging) it on or it may
be diluted with water (up to and applied as a shampoo, depending upon the condition of the animals
hair and skin and the desired results. In either case, several minutes (preferably 10
minutes) should be allowed to elapse to facilitate skin penetration of the oil, before
rinsing the animal with water to remove most of the soap and dirt
."

I need someone to find where this has ever been used for humans. I don't think you'll find it.
I could be wrong of course, but this ends my interest in the matter, and so others are free to take
up from here.

ETA: Aw, heck -- you knew I couldn't stand it...
https://www.canadianwoodworking.com/get-more/tung-oil-debunking-myths

"The earliest reference I can find to the use of tung oil is in the writings of Confucius
around 500 B.C.
The Chinese have used tung oil, also known as China wood oil, for at least 2500
years for wood finishing, wood waterproofing, caulking, inks and paints. I also found
some references to using tung oil for medicinal purposes in ancient history. I don’t
suggest you ingest it or take a bath in it, but apparently some primitive cultures did."


Continuing to research (which I have to say I excel at), I FINALLY found a soap reference!!
https://books.google.com/books?id=PLceAAAAIAAJ&pg=RA3-PA47&lpg=RA3-PA47&dq=tung+oil+medicinals+or+soap&source=bl&ots=RM6PH4fJss&sig=ACfU3U1qVEXo__7ysj1EwXxETt01SN_dLA&hl=en&sa=X&ved=2ahUKEwjY5JGW3vvgAhUGwYMKHf0VBdcQ6AEwDHoECAoQAQ#v=onepage&q=tung oil medicinals or soap&f=false

It was used in the US in 1916 and 1917 during the war when other soap oils were in inadequate
supply. "A leading American soap authority thinks it unlikely that tung oil will ever have an
important place among raw materials for soap manufacture. Tung oil is not a particularly
satisfactory soap ingredient from a technological standpoint
because of its excessive
drying qualities, which result in the production of a soft, mushy soap, subject in many instances
to rancidity. ... The use of tung oil would probably be limited to special soaps for leather dressing
or automobile cleaning
; but for such soaps corn oil and soybean oil are equally suitable."

Okay, NOW I really AM done! Goodnight everyone! If you make soap with this stuff, good luck!
 
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deleted

I think the post I was replying to was not talking about me, after all. ;)
 
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