Is there a Chemist in the house?

[Michael Mutmansky]

I find glut to be much less offensive (odor-wise) than formalin, but I think formalin works better. I think both work better then glyoxol by a large margin, and the $50 spent on a respirator is a small price to pay for real consistant gelatin.

In truth, a respirator should probably be used with all of these, but many people don't with glyoxol, and some don't with glut. Basically, if you have to use the same precautions, then use what you think works best for your purposes...


---Michael

 

[donbga]

As I've said over and over, "Use what works for you".

PE

I should rephrase my initial post. The glut is a 2.5% concentration to start with. A much smaller % ends up in the gelatin. I'd have to look at my notes to be sure but as I recall the amount of 2.5% glut added to the gelatin (3%) is 1.5 ml per 150 ml of gelatin. But please don't hold me to that as I'm working purely on memory.

Never the less glut should be handled with caution, always with eye protection, plenty of ventilation and a respirator.

 

[Kerik]

I tried the Black Magic glut and found it much less effective than formalin or glyoxal. B.M. hardened gelatine resulted in greatly increased pigment staining. I've heard the same results from others. I've never had problems with glyoxal if I use the sized paper right away. However, I often have sized prints laying around for a while before I gum them, so I routinely use formalin for my work and glyoxal in workshops.

 

[donbga]

I tried the Black Magic glut and found it much less effective than formalin or glyoxal. B.M. hardened gelatine resulted in greatly increased pigment staining. I've heard the same results from others. I've never had problems with glyoxal if I use the sized paper right away. However, I often have sized prints laying around for a while before I gum them, so I routinely use formalin for my work and glyoxal in workshops.

Black Magic glut is the wrong glut to use. It contains, as I understand it, sulfates which causes problems. Photographers Formulary now sells glut without sulfates.

 

[Photo Engineer]

Well, I remind you again of the lawsuit over the use of glutaraldehyde which is pending in Australia. There was a lengthy thread on this subject over on Photo Net about a year ago.

In fact, X-Ray film processing was revised (IIRC) to remove the glutaraldehyde over this very suit. The fumes are not immediately annoying as are those of formalin, but they are quite bad over the long haul, from what I understand.

I don't like the odor of Glutaraldehyde or Succinaldehyde not to mention Formaldehyde. Glyoxal works for me and the odor is not objectionable when I have a whole room full of coatings hanging up to dry. And, the material is hard within 2 - 4 hours.

I have had some hardeners set the gelatin in the can before I can begin coating. Glyoxal does not do this unless the pH goes too high.

I remind you of another hardener that is not often mentioned. That is mucochloric acid. I have used that a lot, but not recently.

PE

 

[donbga]

Well, I remind you again of the lawsuit over the use of glutaraldehyde which is pending in Australia. There was a lengthy thread on this subject over on Photo Net about a year ago.

In fact, X-Ray film processing was revised (IIRC) to remove the glutaraldehyde over this very suit. The fumes are not immediately annoying as are those of formalin, but they are quite bad over the long haul, from what I understand.

I don't like the odor of Glutaraldehyde or Succinaldehyde not to mention Formaldehyde. Glyoxal works for me and the odor is not objectionable when I have a whole room full of coatings hanging up to dry. And, the material is hard within 2 - 4 hours.

I have had some hardeners set the gelatin in the can before I can begin coating. Glyoxal does not do this unless the pH goes too high.

I remind you of another hardener that is not often mentioned. That is mucochloric acid. I have used that a lot, but not recently.

PE

I'm not using glut everyday, only very infrequently under the conditions noted. Frankly I could care less about the law suit.

The pH of the glut I use is about 2.5

 

[Photo Engineer]

I'm not using glut everyday, only very infrequently under the conditions noted. Frankly I could care less about the law suit.

The pH of the glut I use is about 2.5

Don, I meant the final pH of the melted chemistry you are about to add the hardener to. Sorry.

PE