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PeterH

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  1. "What pigments that survive the heat" is an easy one: use ones in regular use in pottery. Such as "oxide-washes" and "ceramic stains". @blackthorn mentioned some in one of his earlier posts. Often a little frit or Gertsey borate (or it's modern substitutes) is added to aid the fusion. Temperatures depend strongly on the glaze (or glass) you're fusing onto. Glaze choice constrained by the clay body of your "pot" (must match thermal expansions). I've no idea if anybody has tried #5. You'll probably need to suck it and see ... or get lucky with literature-search/google. On the other hand if it doesn't work pretty much all avenues to fuse an "alternate photographic techniques" image to glaze/glass are probably doomed. Parting thoughts As stated pretty everywhere in these threads: test, test, test. Either it's a thought-experiment or you need to start making & firing at least some test-pieces. Perhaps join a local studio and get a little hands-on experience, and contact with potters at work. You also will only succeed if you can get all the stages (including exposing the 3d object) working right. A chain is as strong as its weakest link, and all that. Obviously you need to safely manage any fumes arising during firing. ... and I should have said that mixed-media is a legitimate choice if it satisfies your objectives. So covering an image on a porous pot with some sort of sealer might meet your needs (varnish, brick sealer, clear paint, ...) and would save a lot of hands-on learning pottery 101+. Or act as a stepping stone to greater things.
  2. There seems to be a degree of mutual confusion. I'll explain my thoughts. Decomposition temperatures 1) If you use a method like pigment-loaded gum-dichromate (or gum-DAS) after exposure and development you finish up with an image consisting of varying thickness of pigment-loaded "gum". 2) Essentially you have created a "transfer" in-situ. Either sitting on top of a glass/glaze or within the top layers of a porous ceramic. 3) At this point the dichromate/DAS has served its purpose, and can be burned-out with the gum during the firing. 4) Hopefully the pigment will stay in sufficiently close proximity to the surface to be fused/incorporated into it during the firing. There is absolutely no need to look for light-sensitive materials with a high decomposition temperature for this process. Cyanotype You state that cyanotype "can be fired to ceramic but not to glass", a reference for this would aid the discussion. But here we go: 1) The cyanotype process precipitates out a strongly coloured iron compound, which forms a strong image. If fired this will decompose to a paler iron oxide. Here are some pix of the unfired image. I've yet to see any pix of fired image. https://tinyurl.com/8ubba93x 2) Legalistic quibble. The initial cyanotype process was a liquid process and relied on the backing material (paper,cloth, etc) to hold the precipitated compound in place. This carries over naturally to porous ceramic but not to water-proof glass/glaze. 3) A long-standing solution to this problem is the precipitate the iron compound into a layer of gelatin or similar. https://tinyurl.com/ynhzneer 4) If you want a fired-on image from such cyanotype I would just try firing them. The situation is not that different from transfers or gum-DAS images so the chances of it working are promising. 5) Do we know anybody who has tried this? How successful was the attempt? Finally photo-sensitive glass This presents a completely different and formidable set of challenges. Which I'll comment on in a separate posting.
  3. As you are aware your link gives an article about using this product and a picture of it. On the picture you can see that it's CAS number is 2718-90-3. Aside: A CAS Registry Number, also referred to as CAS RN or informally CAS Number, is a unique numerical identifier assigned by the Chemical Abstracts Service (CAS) to every chemical substance described in the open scientific literature. There is an MSDS for 2718-90-3 (4,4'-Diazido-2,2'-Stilbenedisulfonic Acid, Disodium Salt) at https://fscimage.fishersci.com/msds/67032.htm There is an MSDS for 7778-50-9 (Potassium bichromate) at https://www.fishersci.com/msds?productName=AC197760050 ---------------- PS Anybody know a way of finding MSDSs in a uniform format, the disparate styles don't help comparison. PPS Google translates the warning you mention in the French-language MSDS as: Risk of explosion in case of fire. Fight fire remotely due to the risk of explosion. Be careful as it can decompose on combustion or at high temperatures and generate toxic vapors. My personal suspicion is that this is intended as guidance to fire brigades attending factory fires where there might be drums of the stuff lying about. If this is the case the warning may have little relevance to the owner of a 25/50g bottle. Although I definitely wouldn't throw it on the fire, and take due care disposing of it.
  4. I'm old enough to have made potassium dichromate based indoor fireworks, but that was another time. Maybe @blackthorn can suggest safer/greener sensitisers/processes. These are just a couple of google hits. Gum Diazo Printing v1.4 https://www.alternativephotography.com/gum-diazo-printing-v1-4/ The present paper aims to be a reference guide to anyone in the EU willing to go on printing with pigmented gum while being fully compliant with the actual safety regulations regarding chemical substances (i.e. avoid the use of dichromate, illegal as of September 2017 in the EU). Although many people may have some leftovers of the sensitizing agent still in their cabinets, it’s hard to imagine that anyone would go on using illegal substances even in small quantities, also because health concerns have more than solid background and vast scientific literature is available documenting how hazardous the hexavalent chromium compounds can be. Also A non-toxic alternative to gum dichromate https://www.jstage.jst.go.jp/article/photogrst1964/70/Suppliment/70_Suppliment_74/_pdf/-char/en
  5. I cannot think of any reason why iron oxide cannot be used as the "pigment" in gum-dichromatic style processes. Or any other photographic process with a wash-away binder carrying a pigment. Wouldn't keep banging on about it otherwise. [Or ceramic stains with or without a binder; eg frit or "Gerstley borate"]. PS Just trying to make the point that if you are using a photographic process involving a pigment and wash-away binder you can to some extent decouple your experiments on pigment-selection and photographic delivery. ... of course if your pigment need to be fired it's an open question how well any pigment will adhere to a 3D shape during the firing process. (I doubt that you will find a heat-tolerant adhesive.)
  6. This suggests a variety of ways iron-oxide can be applied to a ceramic glaze. Presumably the same methods would also work on glass. DIY Ceramic Decals From Your Laser Printer (Update: and Magnetic Tape) https://www.instructables.com/DIY-Ceramic-Decals-From-Your-Laser-Printer/ ... including To get the printed image to the ceramic glaze, you can simply glue the paper on the ceramic piece ... This might enable you to test the result for its archival qualities. Before investigating alternative photographic processes to apply the iron-oxide.
  7. I've no idea if hardened (cross-linked?) gelatin melts. If it does it might be worth trying the gum arabic form the gum-dichromate process instead. PS AFAIK the admittedly small quantities of gum arabic historically used as a glaze additive burnt-out cleanly. Use of gum arabic has largely been replaced by the use of CMC (carboxy-methyl cellulose), but I've no idea if this can be used in the gum-dichromate process.
  8. I'm being very careful to say as little as possible, in order not to mislead you. I'm just indicating further research might be worthwhile. If the transfer paper was much cheaper, I'd suggest doing a trial transfer with it to see how "archival" the the fused image is. [But I believe that not all toners contain iron.] If it turned out well it's likely a proof-of-concept that a refractory powder can be fused onto glass, with the burn-out of a carrier (plastic in the case of toner?).
  9. Can I point you to this advert https://tinyurl.com/t53rvyfn Not because I think you will be directly interested in the product, but because it implies that you can [to some extent] fuse iron-oxide to [flat] glass at ~680-800°. And then slump the glass or make multi-layer sandwiches if you wish. @Callie Beller Diesel Does that sound plausible? If it works as advertised it might try fusing with a gum bichromate image rather than printed decals, and perhaps Mason stains rather than iron oxide (esp. those with spinel structure?).
  10. I just tried and the manual is at the link @JohnnyKprovided, suggest you try again with https://community.ceramicartsdaily.org/applications/core/interface/file/attachment.php?id=14499
  11. Look like it's Malatchi CTS Slider Pot 10k Ohm on https://www.surplussales.com//Potentiometers/Slider/Slider-1.html
  12. Is this of any help? http://aakilns.com.au/pdf/novaman1.pdf 1st page is
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