Diazo (Speedball) gelatin hologram
Posted: Mon Sep 27, 2021 2:17 am
Diazo-gelatin (DIAG). This is a follow-up to: https://holographyforum.org/forum/viewt ... 9&start=10
Thanks by the way, vasimv, for pointing to SPEEDBALL.
It appears that their diazo sensitizer for screen printing can be used to make holograms just like DCG. It's easy to use andΒ simple to add spectral sensitizatio to the system. Moreover, it's available in many countries.
So e.g. it can be bought from Amazon etc. This is the specific diazo sensitizer: www.speedballart.com/wp-content/uploads ... l_2021.pdf
It's on page 4, item #9, product #004578, "SPEEDBALL DIAZO SENSITIZER".
The MSD (/www.dick-blick.com/msds/DBH_SDS_433041002.pdf) lists the following chemicals:
4-Diazodiphenylamine / formaldehyde condensate hydrogen phosphate complex
P-diazoldiphenylamine polymer
Phosphoric acid
I assume most things doable with DCG can be done with DIAG, volume reflection, surface relief holograms that is.
I previously tried another diazo, "D.A.S". See: https://holographyforum.org/forum/viewt ... 0&start=20
With D.A.S.-gelatin I could make reflection holograms at 405nm that had the typical DCG look. However, with that diazo it becomes difficult to record holograms at longer wavelengths.
The SPEEDBALL sensitizer (SPS) seems to be compatible with a great many dyes. A Canon patent (US 3778274), "Spectrally sensitized diazo materials", deals with very similar diazo materials ("diazo diphenylamine derivatives such as p-diazo diphenylamine sulphate").
In regards to spectral sensitization it points out:
"Conventional sensitizing dyes, such as those used for sensitizing silver halides and zinc oxide may be used in this invention. Representative examples thereof are: triphenylmethane dyes such as Brilliant Green, Crystal Violet and Acid-Violet 6B; rhodamines such as Rhodamine B, Rhodamine 6G, Rhodamine G Extra, Sulforhodamine B and First-Acid-Eosine G; xanthene dyes such as Eosine S, Eosine A, Erythrosine, Phloxine, Rosebengale and fluorescein; thiazine dyes such as methylene blue, methylene green, methylene violet, methylene azine, thionine blue, toluidine blue, and Thiocarmine R; acridine dyes such as acridine yellow, acridine orange and Trypaflavin; quinoline dyes such as pinacyanol and cryptocyanine; quinone dyes such as alizarine, alizarine red S, quinizarine; cyanine dyes; aryl methane dyes such as Erythrosine 2Na, Rhodamine B 500, Fanal Pink B, Rhodamine 6GDN, and auramine; polymethine dyes such as 3, 3'-diethylthiacarbocyanine iodide; azo dyes such as Eriochrome blue black R, azo methine dyes such as bis(p-dimethylamino benzal) azine; carbonyl dyes such as Solway Ultrablue B, arizaline cyanine green GWA; and phtholocyanine dyes such as Segnale light turquoise NB."
II guess RGB holograms should be possible on such grounds. I've successfully tried methylene blue at 650nm in a SPB-gelatin mix.
Incidentally, there's a 1980 paper by Gladden, "Grating formation in diazo gelatin". Interestingly, he based his tests on very much the same diazo as the one in the SPB sensitizer. He exposed the diazo-gelatin layers at 488nm (625mJ/cm2) and processed them analog to DCG.
For coating I used 4.0g of a 10% gelatin solution to which I had pipetted 1 drop from the SPB stock solution. The stock solution was prepared by simply filling up the original SPB sensitizer bottle with water.
After the laser exposure it's best to "develop" the DIAG layer in an alkali solution. The nature of that solution doesn't seem to matter much - as long as it doesn't attack the gelatin.
I should perhaps mention one downside: after processing, that's-to-say, after alcohol dehydration, a slightly yellow-brown tint persists. Its strength directly depends on the amount of SPB sensitizer in the layer. I've yet to find a solution to that problem.
Thanks by the way, vasimv, for pointing to SPEEDBALL.
It appears that their diazo sensitizer for screen printing can be used to make holograms just like DCG. It's easy to use andΒ simple to add spectral sensitizatio to the system. Moreover, it's available in many countries.
So e.g. it can be bought from Amazon etc. This is the specific diazo sensitizer: www.speedballart.com/wp-content/uploads ... l_2021.pdf
It's on page 4, item #9, product #004578, "SPEEDBALL DIAZO SENSITIZER".
The MSD (/www.dick-blick.com/msds/DBH_SDS_433041002.pdf) lists the following chemicals:
4-Diazodiphenylamine / formaldehyde condensate hydrogen phosphate complex
P-diazoldiphenylamine polymer
Phosphoric acid
I assume most things doable with DCG can be done with DIAG, volume reflection, surface relief holograms that is.
I previously tried another diazo, "D.A.S". See: https://holographyforum.org/forum/viewt ... 0&start=20
With D.A.S.-gelatin I could make reflection holograms at 405nm that had the typical DCG look. However, with that diazo it becomes difficult to record holograms at longer wavelengths.
The SPEEDBALL sensitizer (SPS) seems to be compatible with a great many dyes. A Canon patent (US 3778274), "Spectrally sensitized diazo materials", deals with very similar diazo materials ("diazo diphenylamine derivatives such as p-diazo diphenylamine sulphate").
In regards to spectral sensitization it points out:
"Conventional sensitizing dyes, such as those used for sensitizing silver halides and zinc oxide may be used in this invention. Representative examples thereof are: triphenylmethane dyes such as Brilliant Green, Crystal Violet and Acid-Violet 6B; rhodamines such as Rhodamine B, Rhodamine 6G, Rhodamine G Extra, Sulforhodamine B and First-Acid-Eosine G; xanthene dyes such as Eosine S, Eosine A, Erythrosine, Phloxine, Rosebengale and fluorescein; thiazine dyes such as methylene blue, methylene green, methylene violet, methylene azine, thionine blue, toluidine blue, and Thiocarmine R; acridine dyes such as acridine yellow, acridine orange and Trypaflavin; quinoline dyes such as pinacyanol and cryptocyanine; quinone dyes such as alizarine, alizarine red S, quinizarine; cyanine dyes; aryl methane dyes such as Erythrosine 2Na, Rhodamine B 500, Fanal Pink B, Rhodamine 6GDN, and auramine; polymethine dyes such as 3, 3'-diethylthiacarbocyanine iodide; azo dyes such as Eriochrome blue black R, azo methine dyes such as bis(p-dimethylamino benzal) azine; carbonyl dyes such as Solway Ultrablue B, arizaline cyanine green GWA; and phtholocyanine dyes such as Segnale light turquoise NB."
II guess RGB holograms should be possible on such grounds. I've successfully tried methylene blue at 650nm in a SPB-gelatin mix.
Incidentally, there's a 1980 paper by Gladden, "Grating formation in diazo gelatin". Interestingly, he based his tests on very much the same diazo as the one in the SPB sensitizer. He exposed the diazo-gelatin layers at 488nm (625mJ/cm2) and processed them analog to DCG.
For coating I used 4.0g of a 10% gelatin solution to which I had pipetted 1 drop from the SPB stock solution. The stock solution was prepared by simply filling up the original SPB sensitizer bottle with water.
After the laser exposure it's best to "develop" the DIAG layer in an alkali solution. The nature of that solution doesn't seem to matter much - as long as it doesn't attack the gelatin.
I should perhaps mention one downside: after processing, that's-to-say, after alcohol dehydration, a slightly yellow-brown tint persists. Its strength directly depends on the amount of SPB sensitizer in the layer. I've yet to find a solution to that problem.