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dr5chrome
08-16-2012, 01:15 PM
Just an FYI - There has been an unknown recent radical jump in the 'wholesale' cost of Hydroqinone.

10mo ago the agent was less than 4$ a pound. In that time there has been a 250%+ increase.
Unlike other photo developing agents HQ is in many other industry applications:
Tires
Cosmetics
Flat-screen TVs
ALL photo dev solutions.

Thomas Bertilsson
08-16-2012, 01:23 PM
ALL photo dev solutions.

Except Xtol, if I remember correctly.

Photo Engineer
08-16-2012, 01:30 PM
There has been either a big jump in price or a decrease in availability of many photographic chemicals in the last year. HQ is just one of them. Much of the US supply came from Texas Eastman which is probably scaling way back.

PE

Michael R 1974
08-16-2012, 03:25 PM
Except Xtol, if I remember correctly.

Correct. No HQ in there. XTOL is a Dimezone-Ascorbate developer. Rodinal, D23, Perceptol and other formulas don't contain HQ either. Even D76 can be altered slightly and made to work the same without HQ (Haist version). Print developers are another matter. HQ in pretty much everything.

Bob Carnie
08-16-2012, 04:01 PM
Michael

could you post the formula for D76 without HQ?


Correct. No HQ in there. XTOL is a Dimezone-Ascorbate developer. Rodinal, D23, Perceptol and other formulas don't contain HQ either. Even D76 can be altered slightly and made to work the same without HQ (Haist version). Print developers are another matter. HQ in pretty much everything.

dr5chrome
08-16-2012, 04:42 PM
..Im getting the quake in Japan - but there are other big manufactures in China. Given there are other uses other than 'photo' [maybe bigger], I cant see a 250% jump as justified. If we though we have seen sticker-shock, just wait till this hits the pike. ..just me: I use 100lbs a year. dw



There has been either a big jump in price or a decrease in availability of many photographic chemicals in the last year. HQ is just one of them. Much of the US supply came from Texas Eastman which is probably scaling way back.

PE

Ektagraphic
08-16-2012, 05:17 PM
Perhaps if Kodak makes Hydroquinone themselves, Kodak products will not see a huge jump?

Photo Engineer
08-16-2012, 06:01 PM
..Im getting the quake in Japan - but there are other big manufactures in China. Given there are other uses other than 'photo' [maybe bigger], I cant see a 250% jump as justified. If we though we have seen sticker-shock, just wait till this hits the pike. ..just me: I use 100lbs a year. dw

IIRC, Kodak spun off Texas Eastman years ago so that is no assurance.

My information comes from companies making chemicals in the US. Hypo no longer ships in tank car lots, but in carboys due to decreased demand. This goes for several other chemicals including some members of the Phenidone family. There is a thread on this here on APUB about 2 months ago.

PE

Gerald C Koch
08-16-2012, 07:19 PM
Michael

could you post the formula for D76 without HQ?

You cannot just substitute ascorbic acid for hydroquinone. As has been stated many times on APUG the resemblence between these two chemicals is only superficial. Xtol is probably the closest ascorbic acid analog for for D-76 after all the correct adjustments to the formula have been made. Search on APUG for the formula which has been posted on more than one occasion.

There is also the Haist modification to D-76 which eliminates the hydroquinone and increases the metol content slightly. It is referred to as D-76H and is used just like D-76. Note that the name uses a captal H since there is another completely different version of D-76 referred to as D-76h.

D-76H

water (125F) 750ml
metol 2.5g
sodium sulfite (anhydrous) 100g
borax (decahydrate) 2.0g
water to make 1 liter

The version above is used as a one shot either FS or 1+1.

Michael R 1974
08-16-2012, 08:06 PM
I was not suggesting replacing HQ with ascorbic acid in any formula. I've stated many times on here I do not believe in simple substitution formulas. Once something is changed, the entire formula needs to be looked at and possibly rebalanced, or scrapped.

Bob - the formula Gerald posted for the Haist version of D76 (D-76H) is correct. The formula is the same as D-76 except the HQ is eliminated and the Metol is increased to 2.5g. Image characteristics are said to be virtually identical. As for its capacity compared to regular D-76, I cannot say.

Athiril
08-16-2012, 08:16 PM
The price rose massively here some time ago, over a year ago iirc.

jnanian
08-16-2012, 08:16 PM
You cannot just substitute ascorbic acid for hydroquinone. As has been stated many times on APUG the resemblence between these two chemicals is only superficial. Xtol is probably the closest ascorbic acid analog for for D-76 after all the correct adjustments to the formula have been made. Search on APUG for the formula which has been posted on more than one occasion.

There is also the Haist modification to D-76 which eliminates the hydroquinone and increases the metol content slightly. It is referred to as D-76H and is used just like D-76. Note that the name uses a captal H since there is another completely different version of D-76 referred to as D-76h.

D-76H

water (125F) 750ml
metol 2.5g
sodium sulfite (anhydrous) 100g
borax (decahydrate) 2.0g
water to make 1 liter


The version above is used as a one shot either FS or 1+1.

hi gerald


this is kind of like split d23 ( dd23 ) or one version of it,
but mixed together ..
i had heard years ago that when mixed together it was pretty much like d76 ( or one of its variants )
thanks for posting this !

john

Gerald C Koch
08-16-2012, 08:40 PM
Hi Michael,

I know that you would not advocate a simple substution. I was answering Bob C's post which appearred to ask just that question. I also wanted to post D-76H as a remedy to the cost of hydroquinone. Since there is nothing to regenerate the metol as it is used up this version cannot be replenished. Looking back I was probably a bit rude to reply since Bob's question was addressed to you. My apologies.

Jerry

Gerald C Koch
08-16-2012, 08:55 PM
Hi John,

I have used D-76H in the past and the results appear to be identical to those of D-76. This formula also points out that at the low pH of D-76 the main purpose of the hydroquinone is to regenerate the metol as it is consumed. This can be seen from the rather small adjustment to the metol to compnsate for the lack of developing activity from the hydroquinone.

Jerry

walbergb
08-17-2012, 01:14 AM
There is a thread on this here on APUB about 2 months ago.

PE

APUB? PE, have you been drinking or got drinking on your mind?;)

Bob Carnie
08-17-2012, 09:22 AM
Thank you both


I was not suggesting replacing HQ with ascorbic acid in any formula. I've stated many times on here I do not believe in simple substitution formulas. Once something is changed, the entire formula needs to be looked at and possibly rebalanced, or scrapped.

Bob - the formula Gerald posted for the Haist version of D76 (D-76H) is correct. The formula is the same as D-76 except the HQ is eliminated and the Metol is increased to 2.5g. Image characteristics are said to be virtually identical. As for its capacity compared to regular D-76, I cannot say.

Keith Tapscott.
08-17-2012, 10:19 AM
could you post the formula for D76 without HQ?I read somewhere that DK-76b is an official Kodak formula without hydroquinone, but I could be mistaken.

http://www.digitaltruth.com/data/dk76b.php

Photo Engineer
08-17-2012, 10:35 AM
APUB? PE, have you been drinking or got drinking on your mind?;)

Drinking? Not that early. Just an error while touch typing, one that I missed. ;)

PE

Michael R 1974
08-17-2012, 04:34 PM
Hi John,

I have used D-76H in the past and the results appear to be identical to those of D-76. This formula also points out that at the low pH of D-76 the main purpose of the hydroquinone is to regenerate the metol as it is consumed. This can be seen from the rather small adjustment to the metol to compnsate for the lack of developing activity from the hydroquinone.

Jerry

Hi Gerald, sorry about that I must have been in one of my moods when I was reading the thread...:)

Indeed it seems in many low pH, dual-agent fine grain developers there is functionally one primary agent doing the direct development (Metol in the case of D76) while the secondary agent's function is to regenerate the primary agent. In the case of MQ developers like D-76 as you point out the pH is too low for HQ to be active enough as a primary developing agent.

Interestingly this appears to be the case with modern Metol-Pyrogallol developers too, where the working pH (below 10 in the cases of both WD2D and PMK) is too low for Pyro to do much direct developing.

What is your take on XTOL though? At its working pH it would appear the Phenidone derivative is the direct developing agent and the ascorbic acid regenerates the Phenidone. However I remember reading that Zawadzki believed the ascorbic acid was the primary developing agent. That might have been a misquote though.

RattyMouse
08-17-2012, 07:18 PM
Drinking? Not that early. Just an error while touch typing, one that I missed. ;)

PE

Come on PE, we wouldnt blame you for hitting the sauce early and hard. Watching your former company sink almost daily has got to be rough. My last company was bought out by a competitor and essentially shut down. That was a brutal experience that was very hard for me to take, even though I only worked there 6 years. I can't imagine what it would have been like with 20+ years.