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#31
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"David Nebenzahl" wrote in message ...
On 12/23/2004 7:19 AM Beppe Alborč spake thus: i've heard that there are some ecological developers, without a substance called "hidroquinone". Speaking of hydroquinone, do y'all realize that this is the chemical agent thought to be responsible for Michael Jackson's death pallor? - http://itsb.ucsf.edu/~vcr/Freeze2b.html * - http://www.snopes.com/photos/jackson.asp - http://www.robertkotlermd.com/people_news.htm * actually, they say it's "a cream containing monobenzyl ether of hydroquinone (also called benoquin)" Yep, and this was the reason France promulgated a law obliging all photo shops to put the developers containing hydroquinone in closed cupboards ... Regards, -- Claudio Bonavolta http://www.bonavolta.ch |
#32
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#33
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#34
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David Nebenzahl wrote:
On 12/23/2004 7:19 AM Beppe Alborč spake thus: i've heard that there are some ecological developers, without a substance called "hidroquinone". Speaking of hydroquinone, do y'all realize that this is the chemical agent thought to be responsible for Michael Jackson's death pallor? - http://itsb.ucsf.edu/~vcr/Freeze2b.html * - http://www.snopes.com/photos/jackson.asp - http://www.robertkotlermd.com/people_news.htm * actually, they say it's "a cream containing monobenzyl ether of hydroquinone (also called benoquin)" I believe that Hydroquinone was used successfully in fighting malaria in the past, and this is why it was common enough in the early days of photography, when they were trying different compounds to see what could be used as developing agents, it was found to work, and didn't stain the hands, as some other chemicals do.... W |
#35
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I suggest Xtol for film and Agfa Neutol Plus for paper. Both are
Phenidone and Ascorbic acid developers with very low toxicity and good environmental properties. Xtol is sometimes subject to short term loss of activity. I've had this happen recently. However, I don't know of another film developer with only these ingredients. Most other Phenidone film developers also contain hydroquinone. Hydroquinone is not particularly hazardous in a photographic developer but has environmental problems. In general, liquid concentrate developers are less hazardous than powdered ones because they eliminate the danger of airborne particles. There are a number of good liquid concentrate film developers on the market, Kodak T-Max and T-Max RS being among them. Both use a form of Phenidone and Hydroquinone. Agfa Neutol Plus is a liquid concentrate. Richard Knoppow Los Angeles, CA, USA |
#36
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Richard's correct about Xtol and Neutol.
A home-made version which also does not use Hydroquinone is 5 g sodium metaborate or 6 g sodium carbonate (depending on desired level of activity) 4 g ascorbic acid (Vitamin C powder) 4 ml 1% Phenidone solution (1 g Phenidone dissolved in 100 ml either 90% alcohol or propylene glycol) Starting times at 22C. or 70F: Delta 400 (with metaborate): 6 minutes Delta 100 (with carbonate): 6:45 (with metaborate) 10 minutes Fuji ACROS (with carbonate) 7 (with metaborate) 10 minutes Fuji Neopan (with carbonate) 6:30 substituting borax in the above formula for the carbonate or metaborate will give similar results but somewhat longer times. Larry Richard Knoppow wrote: I suggest Xtol for film and Agfa Neutol Plus for paper. Both are Phenidone and Ascorbic acid developers with very low toxicity and good environmental properties. Xtol is sometimes subject to short term loss of activity. I've had this happen recently. However, I don't know of another film developer with only these ingredients. Most other Phenidone film developers also contain hydroquinone. Hydroquinone is not particularly hazardous in a photographic developer but has environmental problems. In general, liquid concentrate developers are less hazardous than powdered ones because they eliminate the danger of airborne particles. There are a number of good liquid concentrate film developers on the market, Kodak T-Max and T-Max RS being among them. Both use a form of Phenidone and Hydroquinone. Agfa Neutol Plus is a liquid concentrate. Richard Knoppow Los Angeles, CA, USA |
#37
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On Sun, 26 Dec 2004 18:45:00 -0500, The Wogster
wrote: I believe that Hydroquinone was used successfully in fighting malaria in the past, and this is why it was common enough in the early days of photography, .... Perhaps you were thinking of quinine ? Not that hydroquinone and quinine aren't related. In fact quinine is a very complex compound as shown in the following : "quinine bark chemicals include: aricine, caffeic acid, cinchofulvic acid, cincholic acid, cinchonain, cinchonidine, cinchonine, cinchophyllamine, cinchotannic acid, cinchotine, conquinamine, cuscamidine, cuscamine, cusconidine, cusconine, epicatechin, javanine, paricine, proanthocyanidins, quinacimine, quinamine, quinic acid, quinicine, quinine, quininidine, quinovic acid, quinovin, and sucirubine." It was used to treat numerous ailments though malaria was certainly it's cheif usage. Quinine - C20H24N2O2 The following from : http://www.ibiblio.org/herbmed/eclec...hona_alka.html Thus, by the ring-arrangement of atoms peculiar to this series, there are formed from Benzene, (C6H6), the following substances, viz.:— Phenol, or Carbolic Acid, C6H5OH-by replacing H by OH, (hydroxyl). Pyrocatechin, or Ortho-di-hydroxy-benzene, C6H4(OH)2—by replacing 2H by 2OH. Resorcin, or Meta-di-hydroxy-benzene, C6H4(OH)2—by replacing 2H by 2OH. Hydroquinone, or Para-di-hydroxy-benzene C6H4(OH)2—by replacing 2H by 2OH. Pyrogallol, Pyrogallic Acid, Tri-hydroxybenzene C6H3(OH)3,—3H by 3OH. Amido-benzene, or Anilin, C6H5.NH2—by replacing H by NH2 (amidogen). Nitro-benzene, C6H5.NO2—by replacing H by NO2 (nitroxyl). Benzoic Acid, C6H5CO.OH—by replacing H by CO.OH (carboxyl). Salicylic Acid, HC7H5O3—by replacing 2H by OH and CO.OH. Naphtaline, C10H8—by uniting two Benzenes in an overlapping ring. Pyridin, C5H5N—by replacing tetrad C by triad N. Chinolin, C9H7N—uniting Benzene (C6H6) and Pyridin (C5H5N) Most interesting. I never cease to be amazed at the usage of these chemicals. Regards, John S. Douglas, Photographer - http://www.puresilver.org Please remove the "_" when replying via email |
#38
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On 12/28/2004 2:56 PM John spake thus:
On Sun, 26 Dec 2004 18:45:00 -0500, The Wogster wrote: I believe that Hydroquinone was used successfully in fighting malaria in the past, and this is why it was common enough in the early days of photography, .... Perhaps you were thinking of quinine ? Not that hydroquinone and quinine aren't related. In fact quinine is a very complex compound as shown in the following : "quinine bark chemicals include: aricine, caffeic acid, cinchofulvic acid, cincholic acid, cinchonain, cinchonidine, cinchonine, cinchophyllamine, cinchotannic acid, cinchotine, conquinamine, cuscamidine, cuscamine, cusconidine, cusconine, epicatechin, javanine, paricine, proanthocyanidins, quinacimine, quinamine, quinic acid, quinicine, quinine, quininidine, quinovic acid, quinovin, and sucirubine." Plus, doesn't quinine figure in that most essential of social substances, namely tonic water? Where would mixed drinks be without it? -- Today's bull**** job description: • Collaborate to produce operational procedures for the systems management of the production Information Technology infrastructure. - from an actual job listing on Craigslist (http://www.craigslist.org) |
#39
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On 12/28/2004 2:56 PM John spake thus:
On Sun, 26 Dec 2004 18:45:00 -0500, The Wogster wrote: I believe that Hydroquinone was used successfully in fighting malaria in the past, and this is why it was common enough in the early days of photography, .... Perhaps you were thinking of quinine ? Not that hydroquinone and quinine aren't related. In fact quinine is a very complex compound as shown in the following : "quinine bark chemicals include: aricine, caffeic acid, cinchofulvic acid, cincholic acid, cinchonain, cinchonidine, cinchonine, cinchophyllamine, cinchotannic acid, cinchotine, conquinamine, cuscamidine, cuscamine, cusconidine, cusconine, epicatechin, javanine, paricine, proanthocyanidins, quinacimine, quinamine, quinic acid, quinicine, quinine, quininidine, quinovic acid, quinovin, and sucirubine." Plus, doesn't quinine figure in that most essential of social substances, namely tonic water? Where would mixed drinks be without it? -- Today's bull**** job description: • Collaborate to produce operational procedures for the systems management of the production Information Technology infrastructure. - from an actual job listing on Craigslist (http://www.craigslist.org) |
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