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Keep Color Developer away from PETs!

thuggins

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I seem to recall having seen something about this at some point in the past, but it obviously did not make enough of an impression. E-6 Color Developer concentrate will dissolve PET. CD1 is pretty aggressive, CD2 less so but it still will eat thru the bottle in time. The First Developer, Blix and Stabilizer all seem fine in PET.

I can't speak for C-41 (perhaps someone can comment) or the mixed chemicals. It would certainly be wise to steer away from PET for the CD whether concentrated or mixed.

I lost the last two batches for the Tetenal kit this way. Luckily, the new kit is due in from Freestyle tomorrow. The 100ml GLASS bottles are due in today.
 
I would never serve my dog E-6 Color Developer concentrate. If I had a cat, I definitely would!
 
I've kept E6 CD for some months in a pet bottle without any problems. It is quite alkaline at pH 12, but I only had one case of ruined pet bottle which had sodium hydroxide solution in it, much more alkaline and corrosive. I still have a C41 developer bottle from 2 years ago and it's still fine. Perhaps your bottles aren't very good. For the record, I always use fizzy drink bottles and never had a mishap in many years.
 
Same here. I keep all of my chems in fizzy drink bottles just fine. Many many months.
 
Sirius Glass said:
I would never serve my dog E-6 Color Developer concentrate. If I had a cat, I definitely would!
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I know cats love sweet tasting anti-freeze which will kill a cat by shutting down its kidneys. But I remember mixing a Kodak E-6 kit and one of the chems while I was mixing up smelled like artificial grape flavor and it had a purple tinge too.
 
I mixed 5L of ECN2 developer last weekend and filled it into a 5L PET bottle. My deionised water from a particular drugstore comes in those.

I don't expect trouble with it... I hope.
 
PET is succeptible to high pH.
But chemical stability charts typically only refer to single chemical solutions as aggressive medium, not complex solutions. If I remember right just a few weeks ago we got a warning concerning PET and E6.

Also there are at least over here different grades of PET beverage bottles, as single use and returnable bottle, which differ in wall thickness.
 
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Worked in a plant where they would get RC Cola syrup is concentrate. That stuff would eat through everything and anything.

I don't think developer is more acidic than say, Coca Cola or OJ.
 
Developer is alkaline. And PET is resistant to strong acids. Well, should be...
 
I found out the same thing the same way. Welcome to the club! I bought HDPE bottles from Freund container online. You can buy 1 or 1 million bottles from these guys.
 
It's the concentrate . It was only part of the CD. Embrittled and cracked my PET bottles. PET bottles are fine for most dilute solutions. I use them for XTOL etc.
 

According to the MSDS declaration, Tetenal Colortec CD part 1 concentrate has a pH of 13.6. Very, very close to NaOH (pH 14).
 
halfaman said:
According to the MSDS declaration, Tetenal Colortec CD part 1 concentrate has a pH of 13.6. Very, very close to NaOH (pH 14).
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This would probably require a special bottle if long term storage is needed.
 
AgX said:
Also there are at least over here different grades of PET beverage bottles, as single use and returnable bottle, which differ in wall thickness.
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The bottles I used were very thick, much thicker than the typical pop bottle.

I just checked the MSDS for the E-6 kit posted by Freestyle. Here is the breakdown of the pH of the components.

First Developer ..........9.9
CD1............................>13
CD2.............................2
BX1.............................6.8
BX2.............................5.4
Stabilizer.....................4.8

So the First Developer is alkaline, but apparently not enough to damage PET (at least not yet). I was surprised that CD2 is so acidic. One of those bottles is leaking, but that damage could have been caused from the outside in, by the leaked CD1. According to the interwebs, PET is susceptible to concentrated acid. After seeing the alkalinity of the CD1 and the acidity of the CD2, I will be a bit more careful in handling those. All the rest of the chemicals should be fine in PET.

Decanting the concentrate into 100ml bottles is actually very handy. Apart from greatly reducing the potential for oxidation, the subsequent mixing becomes very quick and easy. HDPE is probably the best overall choice. It is more permeable to oxygen, but the difference is probably negligible in real life.
 
The CD1 concentrate contains the Trisodium Phosphate needed for the colour developer and some excess Sodium Hydroxide, along with any other ingredients. Trisodium Phosphate and Sodium Hydroxide are what make it strongly alkaline. The CD2 concentrate likely contains the actual colour developing agent (CD3) and Sodium Metabisulfite as a preservative. The pH 2 value sounds normal and the metabisulfite reacts with excess hydroxide from CD1 to form Sodium Sulfite.
 
Oh, forgot to add...

Considering my last post, the CD1 concentrate probably doesn't contain something easily perishable and it's ok to be kept in its original container, even if partially full. The CD2 concentrate on the other hand would probably benefit from being decanted to smaller, full containers, especially for long term storage.
 
If this source is to be trusted (and I have no reason not to), then one should generally not store photo chemistry in PET bottles. Strongly alkaline or acidic fluids may exhibit problems earlier than milder solutions, but one never knows for certain how long some solution ends up in storage.
 
PET bottles work fine for wimpy black and white dilute chemistry. I found a bottle of XTOL stock that was 11 years old, in a wimpy soda bottle . Got lost in my darkroom ,the developer was the color of a nice pilsner beer. The developer worked fine ( HP5+) and the bottle was unharmed . I have nice bottles, no longer use soda bottles ,if I was short of money I would rather buy film than bottles
Mike
 
AgX said:
Developer is alkaline. And PET is resistant to strong acids. Well, should be...
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I checked again with different listings. In general PET is not resistant to strong Alkali AND Acids. Though resistance to Acids still seems better.

Those listings all should be taken with a grain of salt. One differs strictly for concentrations and temperature, but only offers few results. The other gives more results but does not differenciate at all. Also the classifications of harm are hard to compare between listings.
 
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AgX said:
I checked again with different listings. In general PET is not resistant to strong Alkali AND Acids. Though resistance to Acids still seems better.
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Agreed, I trust Tetenal, use what they use and never a problem.
 
I prefer glass. Though a bellows system is attractive.
 
Since I have kids, I go through great efforts to never ever store any non-food item in a bottle which was ever meant for food storage. It shall not even look similar to one.

All the pharmacies I ever interacted with sell decent bottles for chem storage for a real pittance, typically much cheaper than the first batch of photographic liquid you will fill them with. Unlike most bottles for drinks, lab bottles have some section of developable surface, and any labels (you do label your photo chems, yes?) will actually stick to them well.

I'm most definitely not in the "use safety goggles, gloves, respirator and an apron when refilling your salt dipper" camp, but chem storage is something everybody should seriously do correctly. A gallon sized spill of PMK in residential area probably costs a lot more than all you ever spent on photography.
 
Rudeofus said:
A gallon sized spill of PMK in residential area probably costs a lot more than all you ever spent on photography.
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Is not just that one of the reasons photographers consider plastic bottles instead ones from glass?
 
AgX said:
Is not just that one of the reasons photographers consider plastic bottles instead ones from glass?
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A spill (e.g. from a dropped bottle) happening while you are present is nasty, but a spill happening while you are away (e.g. from a slowly disintegrating bottle) is much more dangerous. Pharmacies and photo supply stores sell plastic lab bottles, too, and these plastic bottles are suitable for any photographic liquid you'll ever legally own.
 
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