APX 100 dissolves in water!!!

[dpurdy]

I pulled an older 120 APX100 neg out of the files to make a print and found the neg I needed on the strip had a small brown stain on the corner. I tried cleaning it with alcohol with no luck. I decided to soak it in plain water a while. I checked it after a couple of hours and the stain wasn't going anywhere. So I gave up and used an alternate neg and left that strip of 4 negs in the tray of water. I forgot all about it and just now remembered and went to get it and after soaking in plain water for 4 days the negative strip was absolutley clear!! Not a thing on it.. no base fog no images nothing.. except of course the brown stain was still there. It seems that soaking in water for all that time caused the emulsion to dissolve off the film! I wasn't aware of that possiblility. Am I right?
Dennis

 

[Larry Bullis]

Was there any change in the viscosity or color of the water? We know from experience with Jello that gelatin will dissolve.

 

[PHOTOTONE]

Yep...long term soaking of gelatine emulsions in water can cause them to dissolve right off the base.

 

[Ian Grant]

Bacteria and fungi can eat the gelatin. They obviously found your APX neg very tasty

Ian

 

[naeroscatu]

nothing unusual; the emulsion on AGFA films is no different than any other. keeping the film submerged for extended time will destroy the emulsion.

 

[Photo Engineer]

Properly hardened film will dissolve with the action of bacteria or fungi as Ian says, but improperly hardened film will dissolve. Properly hardened film with a poor subbing layer or no subbing layer will float off but maintain its integrity as an emulsion floating in the water.

With improperly hardened film, the film begins to melt if the temperature rises above 20 deg C or 68 F which is the melting point of unhardened gelatin in water.

PE

 

[david b]

Are you still going to print it?

 

[dpurdy]

Print it.. only in my dreams. I actually liked the image and the alternate isn't as good.
Gone for ever. From water it came to water it returned..

http://www.pbase.com/dpurdy/image/66316065

Oh well.
dennis

 

[jim appleyard]

Are you still going to print it?

 

[df cardwell]

WATER = The Universal Solvent

.

 

[Larry Bullis]

Water, the universal solvent!

Oh oh. It's raining. I better wait inside till it stops or I'll melt for sure.

 

[Stephanie Brim]

You're made of gelatin?

*pokes Bowzart*

Do you jiggle?

 

[Larry Bullis]

Do you jiggle?

Unfortunately.

 

[ben-s]

I guess this thread should just remind us of the dangers of DHMO: http://www.dhmo.org/facts.html

 

[Larry Bullis]

Thanks. I bet DHMO dissolves film pretty well too. That is a very interesting and informative site. There was a time that DHMO was all the rage; you had to go to the native reservations to buy it, along with tax free tobacco and booze, but it seemed everyone was using it for something or other.

 

[Photo Engineer]

The only real "universal solvent" or something that approaches it is DMSO, Di methyl sulfoxide. Beware.

PE

 

[Kino]

We used to have stickers in our lab that read, "Danger! 1 MILLION OHMS!".

 

[Paul Verizzo]

Did you use aqua regia by mistake?

 

[Larry Bullis]

The only real "universal solvent" or something that approaches it is DMSO, Di methyl sulfoxide. Beware.
PE

Oh, yes, that's right. Thanks, PE. I had it wrong. Couldn't remember the letters. It was DMSO not DHMO. DHMO sounds bad, too, like American health insurance. But DMSO, shoot, people were smearing it on themselves and I don't know what all.

Water is a "good" universal solvent simply because it is NOT Universal, just "semi-universal". How's that for a concept? Like "go halfway to infinity and turn left, then, on past the third barking dog, you'll come to a fork in the road. Take it".

apologies to Yogi Berra.

How'd this start? I think somebody melted a negative. Dennis, did you get your answer?

This is TOO MUCH FUN!

 

[tim_bessell]

Properly hardened film will dissolve with the action of bacteria or fungi as Ian says, but improperly hardened film will dissolve. Properly hardened film with a poor subbing layer or no subbing layer will float off but maintain its integrity as an emulsion floating in the water.

With improperly hardened film, the film begins to melt if the temperature rises above 20 deg C or 68 F which is the melting point of unhardened gelatin in water.

PE

Why then does Kodak publish developments times for temperatures like 21C, 24C, and 27C. I'm I missing something?

Didn't mean to high jack the thread, just curious.

 

[MattKing]

Why then does Kodak publish developments times for temperatures like 21C, 24C, and 27C. I'm I missing something?

Didn't mean to high jack the thread, just curious.

Because no Kodak film is improperly hardened?

Just a guess.

Matt

 

[tim_bessell]

thanX Matt.

After I posted that question, I though maybe that was the case.

 

[jim appleyard]

I guess this thread should just remind us of the dangers of DHMO: http://www.dhmo.org/facts.html

Does DHMO dissolve in water?

 

[Photo Engineer]

Kodak films are hardened to withstand temperatures up to 38 deg C. I have run them higher than that such as 40 and 45 deg C. Not all films they make will withstand that, but they are hardened well. I presume that Fuji and Ilford products are the same in hardening. Without hardener, films will melt at about 70F, 20 C and with poor hardening they may melt, dissolve or just reticulate if sujbeted to temps much above 20 C.

DMSO = Di Methyl SulfOxide, and is quite dangerous as it will directly penetrate skin and take anything dissolved in it into the body. Thus, as mentioned above, you can dissolve an asprin in DMSO and rub it on your forehead and get almost instant relief for a headache, or rub the mixture on a swollen injured knee and get almost instant relief there. It is quite dangerous though, as anything else is also carried into the body.

DHMO = Di Hydrogen MonOxide or a synonym for water. It is a less potent solvent for some molecules than DMSO and has no where near the ability to penetrate the skin directly. We have a barrier layer to keep water in and out and only allow water to be excreted or expired for the most part.

Therefore, you can kill yourself accidentally by having a poison in DMSO and drop some on your hand, but you could not do this with water. You would have to drink the water.

Hardened film emulsion will dissolve (or come off the film) with treatment in DMSO. Usually, the subbing layer or subbing attachment of the emulsion to the film will dissolve. Some film supports (IIRC) will dissolve in DMSO.

PE

 

[Larry Bullis]

PE,

Thanks, what a great, informative post!