Tween 20 Differences

[ChristopherCoy]

Are there any differences between the different grades of Polysorbate 20? I.e. food grade, cosmetic grade etc?

Also does it come in different colors? I'm only finding it in a yellowish color. Does this affect the highlights at all?

I ask because 4oz at this place is half the cost of 100ml at B&S, and its free shipping.

 

[nmp]

Tween 20 is a trademarked liquid. Polysorbate 20 is the generic, hence the price difference (plus B&S panache.) Chances are they are all probably made by the same people in the world. I bought mine from eBay as well labeled simply as Polysorbate 20, it works fine as far as I can tell. I suppose food grade is probably purer than the cosmetic, but not sure. Either would work for alternative processes. The color is off-white slight yellow but it is used in such a minute quantity, it makes no difference to the color on the paper. You certainly do not want one that has some external color mixed in.

 

[fgorga]

Should be fine... I would not worry about the pure compound being yellow.

The amount used is very small and, if you are washing your prints well, there will be none left in the final print anyway.

I recently bought this... https://www.amazon.com/gp/product/B01FY41OOM/ and it has been working fine. Not quite as cheap as the one you linked to, but reasonable.

 

[Jerevan]

I have bought Polysorbate-20 for possible future use, but for the sake of curiosity, would Photo-flo give a similar result? That is, letting the solution sink into the paper?

 

[nmp]

I have bought Polysorbate-20 for possible future use, but for the sake of curiosity, would Photo-flo give a similar result? That is, letting the solution sink into the paper?

Have not done a comparison myself but I have seen anecdotal reports of use of Photo-Flo or Ilfotol in place of T-20. Looks like the active ingredient in Photo-Flo (Triton X-100) is similar to T-20 in the sense that both have long chain of poly(thelene oxide) (the water-loving part) attached to a molecule that is hydrophobic. In case of T-20 that molecule is a linear hydrocarbon (portion of a fatty acid) whereas in Photo-flo it is a shorter molecule containing an aromatic group. If I had to guess, I would say Photo-Flo would work fine - the only thing to worry about is how much to use since T-20 amounts may not be directly comparable. Also, Photo-Flo is already diluted form of Triton X-100, not pure surfactant like T-20.

:Niranjan.

 

[fgorga]

I agree with Niranjan's comments.

The MSDS for photo-flo, lists its composition as:

Weight % - Component - (CAS Registry No.)
60-70 Water (007732-18-5)
25-30 Propylene glycol (000057-55-6)
5-10 p-tert-octylphenoxy polyethoxyethyl alcohol (009002-93-1)

The last ingredient is the Triton X-100 that Niranjan mentions.

Thus the concentration of Triton X-100 in Photo-Flo (5-10%) is similar to the concentration of Tween-20 stock solution typically used when coating paper. (My Tween-20 stock is 10% w/v.) Therefore, I would use Photo-Flo at the same concentration as Tween-20 when adding it to sensitizer.

I doubt that the propylene glycol included in Photo-Flo will have an adverse effect , but I would test it on a small sample before coating a lot of paper.

Personally, I would probably only use Photo-Flo only if I could not obtain Tween-20 for some reason.

 

[ProfessorC1983]

I use a 5% solution of Triton X-100 as a direct substitute to Tween 20 in various sensitizers and it works a treat.

 

[Jerevan]

Thanks for the answers on the differences - I do have Polysorbate 20 in 500 ml bottle, so I guess I am going to be set for a while. And if I should run out, then additionally I have a full bottle of Adox Adoflo on the shelf ...

 

[nmp]

...I guess I am going to be set for a while.

You can say that again!

Let's see. If you make 10% solution, that's 4000 ml. If you use a generous 4 drops per every 8"x10" print, at approx. 0.05 ml per drop, that's 0.20 ml per print. 4000/0.2 = 20000 prints.

 

[jonmon6691]

Reviving thread for a follow-up question if anyone knows, more about the general interchangeability of the detergents; I have some ilfotol that I use as a wetting agent on sheet film; 1 drop per 500ml in the development tank, any more and it leaves gummy residue on the film

Here's what the safety datasheet says: (https://www.ilfordphoto.com/wp/wp-content/uploads/2017/04/Ilfotol-EN-H17-44-10256.pdf)
isotridecanol, branched, ethoxylated <2.5%
2-PHENOXYETHANOL <1.5%

I'm not a chemist in any way so I'm not sure if there's some equivalency to the photoflo formula, but my real question is

Can Polysorbate 20 be used as a wetting agent for drying film interchangeably with ilfotol or photoflo? I'd rather just keep one in stock and use that for multiple things...

 

[nmp]

Reviving thread for a follow-up question if anyone knows, more about the general interchangeability of the detergents; I have some ilfotol that I use as a wetting agent on sheet film; 1 drop per 500ml in the development tank, any more and it leaves gummy residue on the film

Here's what the safety datasheet says: (https://www.ilfordphoto.com/wp/wp-content/uploads/2017/04/Ilfotol-EN-H17-44-10256.pdf)
isotridecanol, branched, ethoxylated <2.5%
2-PHENOXYETHANOL <1.5%

I'm not a chemist in any way so I'm not sure if there's some equivalency to the photoflo formula, but my real question is

Can Polysorbate 20 be used as a wetting agent for drying film interchangeably with ilfotol or photoflo? I'd rather just keep one in stock and use that for multiple things...

Photo-Flow contains quite a bit of propylene glycol (~30%) in additon to Triton X-100 which, and my memory is too vague as to how exactly, apparently plays an important role too. So my first order guess would be the reverse is not applicable here (i.e using T-20 in place of Photo-Flo.)

:Niranjan.