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  1. #1
    holmburgers's Avatar
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    Developers in Tablet Form - Coincidence or Destiny?

    Ok, so I ask 'coincidence or destiny?' because last night I was reading through a book with a boat load of old developer formulas (W&J's PF&F) and among them were a few references to tablet form developers. This lit a light bulb...

    And what do I see when I log in this morning?? This thread.... http://www.apug.org/forums/forum37/9...developer.html using "frisk" tablets.

    So, it seems that it is indeed destiny.

    In all seriousness, a tablet seems like a very convenient way to package dry chemicals and especially for intermittent users of chemistry.

    What I'd like to know is how to make tablets. What is the binding agent? I'm sure there are a million patents in this vein, but I haven't looked yet.

    I hope that the above mentioned OP will chime in.

    Thanks!
    If you are the big tree, we are the small axe

  2. #2
    Steve Smith's Avatar
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    So rather than mix up the whole of the contents to e.g. one gallon like you do with D76, you want to thoroughly mix the dry ingredients then add some sort of binder and mould it into convenient tablet form so you only mix the right amount at the time you want it.

    It sounds like a good idea to me and I'm sure it can be done.


    Steve.
    "People who say things won't work are a dime a dozen. People who figure out how to make things work are worth a fortune" - Dave Rat.

  3. #3
    holmburgers's Avatar
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    Yeah, that's basically it! Another alternative, would be to mix up your own chemistry and put it into tablet form.

    I guess one good question is, if I can make a suitably homogenous mix, what's the advantage of tablet form as opposed to powder in little baggies or something?

    But, I suppose it would be convenient and well, fun. Furthermore, perhaps a coating on the tablets could effectively seal the ingredients from oxidation, and thus the storage container wouldn't be as critical.

    The wiki articles on pills & tablets (pharmacy) are pretty insightful. Some common binders (excipients) include glucose and hydroxymethylcellulose.
    If you are the big tree, we are the small axe

  4. #4

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    If kodak sold that I would be all over it, hell if anyone sold that I would be all over it, especially for the rare chemicals I dont use often but for some reason have to buy in massive quantities.

  5. #5

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    Apparently "Tabloid" brand photographic chemicals and kits were readily available for many years up to the late 1940's...I've often wondered why the idea was never revived in later times, when small-scale amateur darkroom work was more popular.

    There are references to the history on:-

    http://www.wellcome.ac.uk/About-us/H.../WTX051562.htm

    http://www.dartfordarchive.org.uk/te...euticals.shtml

  6. #6
    holmburgers's Avatar
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    Yeah, that's exactly what I thought. Imagine, you have a pill of D-76 (or whatever) that's measured for 500mL, drop it in and you're good to go. 1L, no problem, drop in two.

    There are many pill presses and pill rollers on eBay and the like. Apparently herbal medicine folks do this kind of thing.

    Thanks for the links!
    If you are the big tree, we are the small axe

  7. #7
    vpwphoto's Avatar
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    I know a guy here at Purdue that does this sort of thing with medicines. He is working on tablet food... I told him if only he could do Merlot in tablet form without the "gritty" feel of his coffee tablets. (Yes he has coffee chewables).

  8. #8
    nhemann's Avatar
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    The idea of tablet form developers is pretty cool but I would make these comments. 1) tablets can be a real bastard to dissolve completely, especially if you have a coating on them to prevent oxidation (and hence water uptake.) You can actually buy sodium sulfite tablets but they are so annoying to use that it was easier to just use granulated. 2) I basically do what you are describing - I just calculate the amount of dry chem I need for a volume and weight it out - even cheapo scales are accurate to a tenth of a gram.
    "There is no such thing as objective reality in a photograph"

    My flickr and (gasp!) dpug photos - take a look if you like.

  9. #9
    holmburgers's Avatar
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    I fear you are right. I don't know if it offers much of an advantage, but I will say that I wish that someone manufactured and sold them in this manner.

    If coated in CMC gum (hydroxy methyl cellulose) or even gelatin, they would definitely require hot water to dissolve quickly. And after that, now you need to cool your solution back down to 20°, kind of negating the convenience and use-when-needed aspect. So yeah... hmmm, sounds good on paper I guess.

    But if the right advantage comes to light, it'd be a fun project!
    If you are the big tree, we are the small axe

  10. #10

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    If you are thinking dissolve the tablet and you're ready to go, your development times will have to be adjusted, or wait until the next day to allow the dissolved O2 in the water to do its thing. I guess that's not too much trouble, for the convenience of it.

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