ILFOCHROME HOME-BREWED BLEACH

[largeformat pat]

I will watch with held breath..............................

 

[AgX]

Quinoxaline 7K is 2,3,6-trimethylquinoxaline...the active dye bleach catalyst. This is the molecule that I now synthesize.

I remember there was some discussion here at Apug some years ago on details of that catalyst synthesis. But I can't find that thread back.

 

[brookse]

Thanks for the recent posts !

Wayne: Currently, the process is indeed hybrid, and a bit longer than what you are used to...but this is mainly because I am at the low end of the concentrations of the active ingredients in the bath. Thus, at present, the bleach is more of a dye-bleach bath rather than a silver-dye-bleach bath. So, I have to get rid of a little silver with the equivalent of a blix operation tacked on (this will change). For the moment, I am also sticking with the divided 1st developer approach, which works well in a drum system. Threfore, things are not quite perfect yet for a 3-tank processor.

I am aware of the APUG posts on hypo modification of standard developers which many of you have used. It would of course be profitable if these experiments were continued.

Pat: It appears to me that many people in Australia have huge, pent-up frustration concerning Ilfochrome due to lack of availability of chemistry...Can you comment?

AgX: Keep searching...I could not find anything myself, except for the encouragement of PE.

I am communicating with a few others via PM. A few issues have cropped up:
1) Many want a way to successfully use hoarded, outdated material. Although, I too have bought alot
of the old RC stuff on e-bay for my work, the unknown variables introduced are not conducive to a rigorous approach at present.

2) For those in other countries, the complex web of international regulation regarding transit is an issue for ME. Having detected that some people are put-off by the prospect of breaking any laws, I have just squeezed my network, and now I can FedX under the umbrella of a biotech company that already has a system for sending molecules worldwide.

3)Any potential takers need a modicum of standard photo chemicals (especially potassium iodide on e-bay), and initially, need to start off with with the easiest images...flatter, compressed tonal range, without large highlight areas.

 

[Wayne]

I'm not sure what you wish to continue in the way of hypo/developers experimentation, seems that has been pretty well explored already. I used home brewed developers including divided developers for years but finally went back to one part because the emulsion changed in the 90s and you could no longer get worthwhile contrast control through varying development. 1/4 teaspoon hypo/liter is what I used, IIRC.

 

[Photo Engineer]

Wayne;

There are several different forms of Sodium Thiosulfate. Which did you use? The pentahydrate? In any case was it the powder form or the pellet form? This makes quite a big difference in the final result.

PE

 

[AgX]

I found that thread on synthesizing that catalyst:

(there was a url link here which no longer exists)

(starting at post #18)

 

[Wayne]

Wayne;

There are several different forms of Sodium Thiosulfate. Which did you use? The pentahydrate? In any case was it the powder form or the pellet form? This makes quite a big difference in the final result.

PE

I always used the pentahydrate crystals. I was told by someone with more experience and smarts than I that the amount of hypo wasnt really critical, there just had to be "some" in there. I never experimented with that so I cant say whether it was true.

 

[Photo Engineer]

The formula as posted in the reference above gives no quantities of ingredients to be used in the bleach. In addition, see my correction to the synthesys. The wrong starting material was specified.

As for the hypo, the amount is critical if one is to prevent loss of dmax and other problems associated with hypo in a developer.

PE

 

[Wayne]

As for the hypo, the amount is critical if one is to prevent loss of dmax and other problems associated with hypo in a developer.

PE

That could be. I think the person who told me that was a former Ilford chemist but I just took his word for it. I just never worried whether my 1/4 t was a bit over or under.

 

[brookse]

AgX: Thanks for the thread reference-I remembered page 1, but for some reason did not follow to pages 2&3 ! ....At any rate, I can sympathize with Grweenfields problems:

1) the starting compound "was dark chocolate brown, and so initially were the quinoxalines." 2) "The difficulty was purifying the black oil/paste by re-crystallisation until it was light enough not to risk staining the prints." 3) "The trimethyl derivative is more difficult to recrystallise."

However, I used a different synthetic protocol which easily produces a catalyst which is light "French Vanilla" rather than "Dark Chocolate."

...Also, Sodium Thiosulfate is still on the bottle labels of the P30 developer part A units that I am using for this work.

 

[brookse]

Hrst in Finland has stepped to the plate! He has already done a nice piece of work with an RA-4 reversal system:

(there was a url link here which no longer exists)

He will receive formulae and enough catalyst to make 2 L. of bleach. Some of the chromes already used in the above thread will then form the basis of experiments on CLM.1M which is just shy of its expiration date.

Que sera sera

 

[Ray Rogers]

Interest is now falling off! I would like first to deal with those who are in the US. Certainly Nicholas, and perhaps akaa. I will PM everyone shortly.

Hrst in Finland has stepped to the plate!... He will receive formulae and enough catalyst to make 2 L. of bleach. Que sera sera

Is US focus is now lifted?

 

[brookse]

Ray.. Originally, the problem for countries other than the US was simply finding a legitimate method of shipping. The international FedX to Hrst required alot of paperwork along with choosing the proper codes for the bleach catalyst. A "no charge" invoice for a "sample" and a "cash value" also have to be indicated. For Hrst, a low $20 cash value was chosen. He will receive the package next week...will any customs be required?...will the chosen codes work?...I don't know right now, but I feel very good about it...and all will be clear shortly. So I think the answer to your question is YES....and there is a good deal of international interest. So just check in again later...especially for Hrst's comments on how things worked in his hands. Of course, some time will be required for all of this...and I assume at least a few problems WILL crop up.... but that's science.

 

[hrst]

I've got the first results now, and I can say that;

This stuff really seems to work. Brookse has done good work. I have perfect black and white, vibrant colors and only little crossover, and quite easily.

There is only a very tiny bit of silver for blix to remove after the dye bleach and fixer.

The very first test sheet was great. No problems arised yet.

I'll continue to work with this and report when I have more specific results.

I'm working with trays.

 

[hrst]

Examples.

CLM 1K. My first tests with home-brew developer and bleach. Agefix 1+5 as fix and then RA-4 blix. There was a bit of visible silver in the campfire picture in the flame before blix.

Scanning is a bit problematic as always, because that super-glossy feeling is missing. I ended up to make raw scans first and then do exactly the same level corrections to every scan, so you really can compare the relative densities. The first one is without hypo in developer. Scanning exaggerates the difference somewhat.

Step wedge steps are 0.15 (half stop).

 

[bwfans]

It looks great!

Though I am a little confused on what kind of chemicals you used in each stage. The only thing I am certain is CLM.1K .

 

[hrst]

2-bath MQ developer (formulas from Brookse), stop, dye bleach with Brookse's super secret catalyst stuff , rinse, fixer (Agefix 1+5), quick rinse, quick RA-4 blix, final wash.

 

[bwfans]

2-bath MQ developer (formulas from Brookse), stop, dye bleach with Brookse's super secret catalyst stuff , rinse, fixer (Agefix 1+5), quick rinse, quick RA-4 blix, final wash.

To further simplify the process with easy access chemicals, have you tried to replace the developer with Kodak Dektol, and replace fixer with Kodak Rapid Fixer? According to an article published 1992, someone uses Dektol 1:2 instead of Ciba developer and Rapid Fix instead of Ciba Fix, plus original Cibachrome bleach, gaining "results practically indistinguishable" from full kit of Cibachrome.

See link here:
http://findarticles.com/p/articles/mi_m1306/is_n2_v58/ai_11882356/

 

[hrst]

Developer is of course the "easiest" part to experiment with. You can try almost anything. 1 bath, 2 bath, different agitations, metol-HQ ratios, pH, bromide and sulfite levels, hypo level or thiocyanate level...... I just started by following the one recommended to me by Brooks. He has done some experimenting, I think.

 

[bwfans]

I agree with that. Replacing original chemical with home-brewed bleach is a big advance. Hope the chemicals in it is not difficult to obtain and cost effective compare with Ilford's.

I wonder what will be the result looks like if processing Ilfochrome in RA4 or even B&W process.

 

[Photo Engineer]

Ilfochrome will be black in both B&W and RA4 chemistry.

PE

 

[bwfans]

Thanks PE. Do you mean total black or a B&W image?

 

[Photo Engineer]

Totally black! No image whatsoever!

PE

 

[bwfans]

Thanks for answering that.

I have some well expired Ilfochrome in unknown condition and try to figure a way to use up them. But sure I am not interested in buying expensive kit just for the fun of it. If there is a more cost effective alternative way to process them.

I am considering photogram or in camera negative. I don't mind color is off and actually would like to see some random color effect like cross processing. Now hrst is working out a home brewed bleach - a good news.

Thanks all for the great work, I read a lot of posts about this topic and know PE has contributed a lof on this.

 

[AgX]

The dyes need to be destroyed to get any whites, and for image forming this bleaching is related to bleaching of the negative (Silver-Dye-Bleaching).