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#1
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Source for paraphenylene diamine (base)
I'd like to try mixing my own 777 developer which requires paraphenylene
diamine (base), but I can't find anywhere to buy it. Can anyone help? -Lew S |
#2
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Lew wrote:
I'd like to try mixing my own 777 developer which requires paraphenylene diamine (base), but I can't find anywhere to buy it. Can anyone help? Try this http://www.photoformulary.com/DesktopDefault.aspx Cheers, Scott. |
#3
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Hi !
You can try at Sigma-Aldrich Chemical company. Great quality, all the products for organic chemistry or research. Cheers ! -- Message posted via http://www.photokb.com |
#4
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Lew wrote: I'd like to try mixing my own 777 developer which requires paraphenylene diamine (base), but I can't find anywhere to buy it. Can anyone help? -Lew S That agent gives poor sharpness. Don't waste your time. |
#5
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UC wrote:
Lew wrote: I'd like to try mixing my own 777 developer which requires paraphenylenediamine (base), but I can't find anywhere to buy it. Can anyone help? -Lew S That agent gives poor sharpness. Don't waste your time. It was well known for giving fine grain in the negatives of the day (1930s? 1940s?), probably because of its solvent action on the silver grains. Of course there would be an acutance penalty for that (might as well use D-25?) that probably did not matter as much with 4x5" and 120 size film as it would with 35mm. Also, there tended to be about a 2-stop speed loss. Since these days you can buy pretty fine grain film, and with small negatives you need (for most images) all the acutance you can get, you may not want to deal with paraphenylenediamine anyway or any solvent develper for that matter. It also has a reputation for being carcinogenic. Derivatives are used in color developers, but they are typically loaded with long hydrocarbon chains to make them less soluble in in things such as human skin. Even if they are not carcinogenic, they are irritating. The reputation that Metol has for being allergenic is mostly (not entirely) due to ppd impurities in it as a result of the early manufacturing process. Ppd does not seem to be a common impurity in it these days. But people can be found who are allergic or sensitive to just about anything. -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jersey http://counter.li.org ^^-^^ 09:35:00 up 49 days, 17:52, 3 users, load average: 4.09, 4.17, 4.17 |
#6
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Jean-David Beyer wrote:
UC wrote: Lew wrote: I'd like to try mixing my own 777 developer which requires paraphenylenediamine (base), but I can't find anywhere to buy it. Can anyone help? -Lew S That agent gives poor sharpness. Don't waste your time. It was well known for giving fine grain in the negatives of the day (1930s? 1940s?), probably because of its solvent action on the silver grains. Of course there would be an acutance penalty for that (might as well use D-25?) that probably did not matter as much with 4x5" and 120 size film as it would with 35mm. Also, there tended to be about a 2-stop speed loss. Since these days you can buy pretty fine grain film, and with small negatives you need (for most images) all the acutance you can get, you may not want to deal with paraphenylenediamine anyway or any solvent develper for that matter. It also has a reputation for being carcinogenic. Derivatives are used in color developers, but they are typically loaded with long hydrocarbon chains to make them less soluble in in things such as human skin. Even if they are not carcinogenic, they are irritating. The reputation that Metol has for being allergenic is mostly (not entirely) due to ppd impurities in it as a result of the early manufacturing process. Ppd does not seem to be a common impurity in it these days. But people can be found who are allergic or sensitive to just about anything. Yep, just do a google search on the chemical name and see what you get... probably 90% allergy and 'this stuff is bad' articles. Scott. |
#7
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On Thu, 10 Mar 2005 09:47:05 -0500, Jean-David Beyer
wrote: UC wrote: Lew wrote: I'd like to try mixing my own 777 developer which requires paraphenylenediamine (base), but I can't find anywhere to buy it. Can anyone help? -Lew S That agent gives poor sharpness. Don't waste your time. It was well known for giving fine grain in the negatives of the day (1930s? 1940s?), probably because of its solvent action on the silver grains. Of course there would be an acutance penalty for that (might as well use D-25?) that probably did not matter as much with 4x5" and 120 size film as it would with 35mm. Also, there tended to be about a 2-stop speed loss. Since these days you can buy pretty fine grain film, and with small negatives you need (for most images) all the acutance you can get, you may not want to deal with paraphenylenediamine anyway or any solvent develper for that matter. It also has a reputation for being carcinogenic. Derivatives are used in color developers, but they are typically loaded with long hydrocarbon chains to make them less soluble in in things such as human skin. Even if they are not carcinogenic, they are irritating. The reputation that Metol has for being allergenic is mostly (not entirely) due to ppd impurities in it as a result of the early manufacturing process. Ppd does not seem to be a common impurity in it these days. But people can be found who are allergic or sensitive to just about anyting. Yep, iwas allergic to Metol, but after massive overexposure, I was left allergic to my own sweat. I used PPD a number of times and found no problems with loss of sharpness. I also used modern PPD derivatrives while experimenting with Sease formulations. I got higher speed, improved grain and sharpness, after including Phenidone. Keep plugging away and experimenting. The radioactive one doesn't have the last word. He' stuck in a time warp. Robert Vervoordt, MFA |
#8
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On photonet, someone did a test and the sharpness loss was quite
noticeable. Robert Vervoordt wrote: On Thu, 10 Mar 2005 09:47:05 -0500, Jean-David Beyer wrote: UC wrote: Lew wrote: I'd like to try mixing my own 777 developer which requires paraphenylenediamine (base), but I can't find anywhere to buy it. Can anyone help? -Lew S That agent gives poor sharpness. Don't waste your time. It was well known for giving fine grain in the negatives of the day (1930s? 1940s?), probably because of its solvent action on the silver grains. Of course there would be an acutance penalty for that (might as well use D-25?) that probably did not matter as much with 4x5" and 120 size film as it would with 35mm. Also, there tended to be about a 2-stop speed loss. Since these days you can buy pretty fine grain film, and with small negatives you need (for most images) all the acutance you can get, you may not want to deal with paraphenylenediamine anyway or any solvent develper for that matter. It also has a reputation for being carcinogenic. Derivatives are used in color developers, but they are typically loaded with long hydrocarbon chains to make them less soluble in in things such as human skin. Even if they are not carcinogenic, they are irritating. The reputation that Metol has for being allergenic is mostly (not entirely) due to ppd impurities in it as a result of the early manufacturing process. Ppd does not seem to be a common impurity in it these days. But people can be found who are allergic or sensitive to just about anyting. Yep, iwas allergic to Metol, but after massive overexposure, I was left allergic to my own sweat. I used PPD a number of times and found no problems with loss of sharpness. I also used modern PPD derivatrives while experimenting with Sease formulations. I got higher speed, improved grain and sharpness, after including Phenidone. Keep plugging away and experimenting. The radioactive one doesn't have the last word. He' stuck in a time warp. Robert Vervoordt, MFA |
#9
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Dear Sirs,
we are the largest manufacturer of para phenylene diamine in India.kindly inform us your requirment.please inform us the quantity and specifications required for your end use.we would certinly assist you by all the possible ways. looking forward to your reply. regards. -- Message posted via http://www.photokb.com |
#10
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Dear Sirs,
we are the largest manufacturer of para phenylene diamine in India.kindly inform us your requirment.please inform us the quantity and specifications required for your end use.we would certinly assist you by all the possible ways. looking forward to your reply. regards. -- Message posted via http://www.photokb.com |
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