C-HQ stability both as solid and in D-58 ?

[Cor]

Chlorhydroquinone is a less well know, perhaps old fashioned developing agent (and a relative of hydroquinone). It primary use is a in warmtone developer such as Defender D-58: I quote from a post made by Randy, another very interesting thread from him on (there was a url link here which no longer exists)
........................................................................................
Here is the formula from the “Photo-Lab-Index” 1949 version

Defender 58-D
Water 750ml
Sodium Sulfite 16.0grams
Chlor-hydroquinone 4.0grams
Sodium Carbonate 16.0Grams
Potassium Bromide 0.6grams
Water to make 1Liter

Develop for at least 4 minutes. With more exposure and less time in the developer tones will be browner but some deepness in the shadows will be sacrificed.

Chlor-hydroquinone stays active even down into the 50s°F range. Much lower then Hydroquinone.
...........................................................

As seen in the link: C-HQ has the ability to develop fairly heavily fogged B&W paper fog free with clear whites. I had some fogged Kentmere Kentona I tried it: works like quite nice, but I have a few questions for those who are perhaps familiar with this developer:

I used a 4 min developing time at 20degC and obtain a nice warm tone image on the Kentmere paper (with a hint of pink/salmon), perhaps a bit weak in de max density. Is this to be expected ?

I diluted the D-58 1:1 with water per the recipe I found also elsewhere, but maybe I should not dilute ?

The next day I wanted to print a few images more, to find out that the developer has almost lost all it's strength. The developer is not keeping well once mixed ?

What colour does the solid chloro-hydroquinone have ? Mine is tan coloured (bought in 2002) and the resulting mixed developer is light brown coloured.

Best,

Cor

 

[Xmas]

Chlorhydroquinone is a less well know, perhaps old fashioned developing agent (and a relative of hydroquinone). It primary use is a in warmtone developer such as Defender D-58: I quote from a post made by Randy, another very interesting thread from him on (there was a url link here which no longer exists)
........................................................................................
Here is the formula from the “Photo-Lab-Index” 1949 version

Defender 58-D
Water 750ml
Sodium Sulfite 16.0grams
Chlor-hydroquinone 4.0grams
Sodium Carbonate 16.0Grams
Potassium Bromide 0.6grams
Water to make 1Liter

Develop for at least 4 minutes. With more exposure and less time in the developer tones will be browner but some deepness in the shadows will be sacrificed.

Chlor-hydroquinone stays active even down into the 50s°F range. Much lower then Hydroquinone.
...........................................................

As seen in the link: C-HQ has the ability to develop fairly heavily fogged B&W paper fog free with clear whites. I had some fogged Kentmere Kentona I tried it: works like quite nice, but I have a few questions for those who are perhaps familiar with this developer:

I used a 4 min developing time at 20degC and obtain a nice warm tone image on the Kentmere paper (with a hint of pink/salmon), perhaps a bit weak in de max density. Is this to be expected ?

I diluted the D-58 1:1 with water per the recipe I found also elsewhere, but maybe I should not dilute ?

The next day I wanted to print a few images more, to find out that the developer has almost lost all it's strength. The developer is not keeping well once mixed ?

What colour does the solid chloro-hydroquinone have ? Mine is tan coloured (bought in 2002) and the resulting mixed developer is light brown coloured.

Best,

Cor

I used a different developer but...

You could try two experiments

i) increase exposure and increase dev tilme to 8 minutes.

if that produces better density

ii) all below

increase exposure x2 - x3
dilute dev x10
add more potassium iodide
develope for ten minutes

then review the the print you have already with the two new prints... my developer was from a 1935 book...It had one to one hydroquine and chloro so was probably more contrasty.

 

[Gerald C Koch]

Since you have some CHQ you might wish to try the following fine grain developer. This developing agent is one of a small group that are capable of being used alone to produce normal contrast negatives.

Champlin 16 (Edwal 36)

Distilled water (50°C) …………………………………………… 750 ml
Sodium sulfite (anhy) ……………………………………………… 100 g
Chlorohydroquinone ……………………………………………………… 50.0 g
Triethanolamine, 90%¡ ……………………………………………… 11.0 ml
Distilled water to make ………………………………………… 1.0 l

Note that the formula specifies 90% TEA, which also contains 10% DEA (technical grade), it will not work correctly with the 100% product. This is because the DEA raises the pH of the working developer.

For use the concentrate is diluted 1+9 with a 10% solution of sodium sulfite.

 

[Gerald C Koch]

To avoid confusion with the Kodak developers the Dupont/Defender developers were numbered 58-D not D-58. Knowing this saves a lot of unproductive searches.

In the past CHQ was used almost exclusively in warm tone paper developers. This was due to its limited availability, cost and the fact that it confers no other advantage over conventional developing agents other than in producing warm tones.

 

[Xmas]

Found my book

recipe for chloro bromide papers
Chlorquinol-Hydroquinone for serpia to red chalk

Chlorquinol 60 gr (note not grammes but some strange imperial unit)
Hydroquinone 60 gr
Sodium Suphite cryst. 2.5oz
Sodium Carbonate cryst. 2.5oz
Potassium Bromide 6 gr
Water to 20 oz

table for colour

colour | exposure | dilution | extra KBr | dev time approx
| | | 10% soln |
warm black | normal | none | none | 1.5 to 2 mins
serpia | x3 | 10 times | 1 ml (cc) | 6 mins
brown sepia | x5 | 15 times | 3 ml | 10 mins
Red brown | x6 | 25 times | 5 ml | 18 mins
Red chalk | x7 | 30 times | 6ml | 20 minutes

note getting a real slow chloro bromide paper may be difficult Ive only got Bromesco left.

 

[Cor]

Thanks for the feedback, guys!

I guess I have to experiment a bit further, perhaps D-58 (or 58-D) is a weak developer by nature anyway; only one developing agent, the paper needs loads of exposure, and a long development time.

remains the question: is my C-HQ solid stock from 2002 perhaps oxidised since it has a tan colour as a solid and light brown in the D-58 ? According to the MSDS the colour of the solid should be beige, and mine is light brown/tan.

best,

Cor

 

[Ian Grant]

Chlorhydroquinone went out of use with the introduction of Phenidone. It was found by accident, well customer complaints, that the newly introduced Ilford commercial PQ versions of ID-2 & ID-20 weren't giving consistent Neutral tones, they just used a simple substitution of Metol by the relevant (lesser) amount of Phenidone.

The PQ versions of ID-2, ID20 (& ID-36) were reformulated as ID-67 & ID-62 essentially the same but with the addition of Benzotriazole to control the tone shift.

ID-20 was Ilford's main paper developer, in the reformulated ID-62 PQ version the level of Bromide was halved as well as the addition of Benzotriazole, the formula was then teaked further to give greater warmth by slightly increasing the Bromide level and the Carbonate (no Benzatriazole) to give ID-78 which Ilford then sold as their warm-tone developer (packaged in powder form). Today's Ilford Warmtone developer is derived from ID-78 the major difference being the use of Potassium Carbonate and some hydroxide in place of Sodium Carbonate.

From memory the last commercial developers containing Chlorhydroquinone were made by May & Baker who also manufactured raw chemicals, particularly developing agents, the company merged with two others to form Champion.

Ian

 

[Xmas]

Thanks for the feedback, guys!

I guess I have to experiment a bit further, perhaps D-58 (or 58-D) is a weak developer by nature anyway; only one developing agent, the paper needs loads of exposure, and a long development time.

remains the question: is my C-HQ solid stock from 2002 perhaps oxidised since it has a tan colour as a solid and light brown in the D-58 ? According to the MSDS the colour of the solid should be beige, and mine is light brown/tan.

best,

Cor

Hi Cor

The warm tone developers vary a lot, but Id stick with yours and do more step test strips varying as table above. before trying a different formula.

A plain Hydroquonine developer will give warmish tones the two compound one above even warmer never tried yours.

One problem I never had was the optimum time is a small window the print looks faint but will snap into 'black' too quickly. I avoided this by removing too early cant help that... I needed handcuffs. You may need to use a stop watch and take one too far and develop the next one 30 seconds less etc until you get the best tone density.

But I was using slow chloro bromide paper from 1960 in 1960

If your chemical works in the current formula Id not worry about it - (getting more will be difficult). You get the warmer tones with diluted developer so you are ok with semi expired...

Some one may have a better formula.

I did like the warm tones.

I'm interested in your results with a modern paper.

 

[Ian Grant]

One problem is modern warmtone papers aren't particularly flexible when it comes to altering image colour, you need older papers which had cadmium in them.

I managed to get rich reddish tomes with Agfa Record Rapid before they reformulated without the cadmium using Ilford ID-78. When my last stocks of Polywarmtone arrived from the very last production run it was very fresh, I accidentally over exposed a test strip and pulled it from the developer (ID-78) after 15 seconds the result was a an orange-red.

Another issue is modern warmtone papers get colder as they age, this really only effects the extremes of warmth you can get. I've 4 different warmtone papers at the moment, ADOX MCP 312, Fomatone MG 322 (both RC) and Forte Polywarmtone FB with 350 sheets Ilford Warmtone FB on it's way, I'll be interested to see which give me the warmest tones.

Ian

 

[Cor]

Thanks again,

My main objective was to save all the boxes of kentmere Kentona FB which are fogged. I am a bit surprised about this, these are AFAIK boxes with the old formula containing cadmium. This Kentona fogs even when frozen at -20degC, the only paper which I have which shows this behaviour.

I do use this fogged paper successfully for Lith printing, but since I had this bottle of C-HQ (originally used for a equidensity developer, but that is a different story) I gave the D-58 a try, and was surprised how warm it made the Kentona appear. Very clean bright white edges and highlights though.

best,

Cor

 

[Xmas]

http://www.lostlabours.co.uk/photography/formulae/developers/devID78.htm

If you add potassium bromide to paper developers you should reduce the fog level and shift the colour warm as well.

 

[Photo Engineer]

Chloro-HQ was noted by EK as a developer of little extra value for the cost and difficulty making it. It was never commercialized and fell out of disfavor as other agents could do the same job or better.

PE

 

[Cor]

Chloro-HQ was noted by EK as a developer of little extra value for the cost and difficulty making it. It was never commercialized and fell out of disfavor as other agents could do the same job or better.

PE

I originally used C_HQ in below formula for the Waterhouse effect in TechPan (35mm) with success:

Sodium sulfite anhydrous 18 g
2-Chlorohydroquinone 5 g
Sodium metaborate tetrahydrate (Kodalk) 40 g
Boric acid 2.5 g *
1-Allyl-2-thiourea 0.75 g
Water, distilled, to 1 liter

Admitting that this is quite esoteric and perhaps nowadays only of historic value, nevertheless I still have 10 rolls of TechPan in the freezer..

Anyway more to be found here:

http://unblinkingeye.com/Articles/Yurow/yurow.html

And the other use is it's fog restraining properties.

best,
Cor

 

[Photo Engineer]

Well, I can add then that Fuji, Agfa and Ilford dropped Cl-HQ as well in spite of the effects that are claimed.

Since I have never used it, I am neutral in this. Just commenting.

PE

 

[Gerald C Koch]

Chlorohydroquinone is used in Edwal FG-7. Originally it was listed as such in the MSDS. When it became hard to obtain Edwal began making it in situ from p-benzoquinone and hydrochloric acid. The revised MSDS shows this.

 

[Photo Engineer]

An now Bezoquinone is suspect as a carcinogen.

It used to be used in green ink.

PE

 

[Ian Grant]

Chlorohydroquinone was also used in Crawley's FX-9 with diethyl-p-phenylenediamine sulfate. The developer was said to produce extra fine grain without an emulsion speed loss.

I'd look at substituting Pyrocatechin for Chlorhydroquinone in FX-9, it's something I might try as I have some Genochrome - which seems to have kept well.

Pyrocatehin is also good for warm tone paper developers, hover I prefer to use it as a re-developer (as in IT-8) and wouldn't use it in a print developer I was using all the time.

Ian

 

[Alan Johnson]

See p54 of this 1940 book:
http://babel.hathitrust.org/cgi/pt?id=mdp.39015007557666;view=1up;seq=66
"Chlorhydroquinone is closely akin to hydroquinone but is preferred by some workers because it is faster working,less sensitive to cold and keeps longer.....
Metol-chlorhydroquinone is sometimes used in place of metol-hydroquinone when it is necessary to work at low temperatures.In any metol-hydroquinone developer, 1.3 parts of chlorhydroquinone may be substituted for 1 part of hydroquinone."

 

[timmct]

Some more stuff on CHQ on this thread...

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