Spectral sensitizing dyes

TiO2 is quite light sensitive and can be spectrally sensitized. It also has a rather broad sensitivity to radiation and can capture radiation outside of the visible region.

Images captured with TiO2 are usually printed using digital means and thus this material is outside of our scope here.

Kodak had a full color system based on TiO2 in the '70s.

PE

I think it's this thread, several posts back, in which Bob Crowley brings up photovoltaic-cell dyes.

It's interesting to go back to the 1st post and look at the Eastman Kodak Chemicals list that PE posted; several of those dyes are in the historic literature. It also has the chemical structures of some of the dyes, i.e. Orthochrome T.

Just as an FYI, Ethyl Red (off the OP list) is available at Alfa Aesar http://www.alfa.com/en/GP100w.pgm?DSSTK=A18367&CAS=76058-33-8 for a fairly reasonable price. The nice lady who got back to me told me that shipping ought to be about $10.

They will only ship to a business address.

Also, the second one on the list, 1,1'-Diethyl-2,2'-carbocyanine iodide is available from Alfa Aesar as well http://www.alfa.com/en/gp100w.pgm?dsstk=H31540. That one looks like an infrared dye according to the list.

Is Rhodamine B good for anything? It certainly is cheap enough. OK, I'm done. That company does seem to source a number of interesting looking items off that list, or things that look very close, but not being a chemist I cannot say if they are any good.

Yes, in fact the holographers mention that rhodamine b is a green sensitizer, so it must be worth considering.

My thinking is that pinacyanol chloride is the ideal red sensitizer to start looking at. It sounds like Denise is experimenting with that, and by some accounts it should be a good, deep red sensitizer.

One of the papers in that word file suggests that it's not "a good panchromatic dye" because it has little sensitivity in the green and futhermore doesn't interact well with certain green sensitizers. However, they're looking at it from the perspective of bath sensitization, and also astronomy. For them, they don't need balanced panchromaticity, just continuous sensitization throughout the visible light band, no matter what strength. From there they can use their filters and apply generous filter factors. So perhaps pinacyanol is too spikey for them, which might in fact be good in a panchromatic/red-sensitive emulsion.

Chris;

Why not discuss this with Paul Gilman the next time you visit Rochester.

PE

You can bet that I will Ron!

Getting down to brass tacks...

Pinacyanol (chloride) = 1,1'-Diethyl-2,2'-carbocyanine chloride [CAS #: 2768-90-3], a.k.a. quinaldine blue

Orthochrome T = 1,1'-Diethyl-6,6'-dimethyl-2,3'cyanine Iodide

Pinaflavol (pinaflavole) = 2-(p-Dimethylaminostyryl)-1-ethylpyridinium Iodide [CAS #: 3785-01-1]

Ethyl Red = 1,1'-Diethyl-2,4'-cyanine Iodide [CAS #: 634-21-9]

Eosin Y = 2',4',5',7'-Tetrabromofluorescein (sodium salt) or 2,4,5,7-Tetrabromo-9-(o-carboxyphenyl)-6-hydroxy-3H-xanthen-3-one Disodium salt (CI# 45380), a.k.a. Acid Red 87

Erythrosine B = 2',4',5',7'-Tetraiodofluorescein (sodium salt) or 9-(o-Carboxyphenyl)-6-hydroxy-2,4,5,7-tetraiodo-3H-xanthen-3-one Disodium salt (CI# 45430), a.k.a. Acid Red 51

Neocyanine = 1,1'-Diethyl-11-(4-quinolyl ethiodide)-4,4'dicarbocyanine Iodide

Kryptocyanine (cryptocyanine) = 1,1'-Diethyl-4,4'-carbocyanine Iodide

Acridine Orange = 3,6-Bis(dimethylamino)acridine Hydrochloride (CI# 46005), a.k.a. Basic Orange 14

Benzopurpurine 4B = 3,3'-[3,3'-Dimethyl-4,4'-biphenylyne-bis(azo)]bis[4-amino-1-naphthalene sulfonic acid] Disodium Salt (CI# 23500), a.k.a. Direct Red 2

Congo Red = 3,3'-[4,4'-Biphenylyne-bis(azo)]bis[4-amino-1-naphthalene sulfonic acid] Disodium salt (CI# 22120), a.k.a. Direct Red 28


The following are all from Ron's list in post #1, but they don't have a colloquial name (if you know one, do share!). Copying here for searchability:

(Peak Absorbance 710nm) = 1,1'Diethyl-2,2'-dicarbocyanine Iodide

(Peak Absorbance 668nm) = 3-Ethyl-2-[5-(3-ethyl-2-benzothiazolinylidene)-1,3-pentadienyl]-benzothiazolium Iodide

(Peak Absorbance 650nm) = 1-Ethyl-2-[3-(1-ethylnaphtho)[1,2d]-thiazolin-2-ylidine)-2-methylpropenyl]naptho[1,2d]-thiazolium Bromide or 4,5,4',5'-Dibenzo-3,3'-diethyl-9-methylthiacarbocyanine Bromide

(Peak Absorbance 522nm) = 1,1'-Diethyl-2,2'-cyanine Iodide [CAS #: 977-96-8], a.k.a. pseudocyanine iodide, pseudoisocyanine iodide

(Other) = 2',7'-Dichlorofluorescein or 9.(o-Carboxyphenyl)-2,7-dichloro-6-hydroxy-3H-xanthen-3-one Disodium Salt

(Other) = 5-(p-Dimethylaminobenzylidene) rhodanine [CAS# 536-17-4], EK catalog says rhodamine, but the internet would suggest otherwise...

I'm thinking that in addition to sensitizers, we've got a great list of baby names here...

I did know a guy named "Congo" Red in Jr. High. And now that I think about it, he had a sister named Ethyl!!

That is absolutely hilarious...! hahaha... :joyful:

But Poly Ethyl Smith was the BEST pole dancer.

Sensitizers for Lippmann Photography

This table is reproduced from Hans Bjelkhagen's Silver-Halide Recording Materials: For Holography and Their Processing. Available on Google Books.

In a nutshell, Lippmann used cyanine & chinoline red, Vatenta used cyanine & erythrosine, and Ives used isocol, erythrosine & pinacyanol.

also...

Pinacyanol (1:1000 alcoholic solution) 4mL
Orthocrom T (1:1000 alcoholic solution) 4mL
Acridine orange (1:500 alcoholic solution) 4mL

The particular sensitizing dyes mentioned above and their combinations were discovered and used by H. Lehmann to produce the best correct-color sensitivity ever achieved in Lippmann photography. However, he kept secret his good formula for Lippmann plates and it was not revealed until after his death. If one wants to try this old photographic technique today, these dyes are definitely the first choice. (emphasis mine)

Another List from Bjelkhagen

Here's another great table of sensitizers from Bjelkhagen for silver-halide emulsions.

A lot of repeats, but a few new ones I think.

From here

Color-sensitising by Bathing, by T. Thorne Baker, pgs. 83-86, Process Engraver's Monthly, Volume 14, 1907.

"The following dyes may be used for bathing where red sensitiveness is wanted:-

Pinacyanol (Fuerst)
Pinachrome (Fuerst)
Orthochrome T. (Fuerst)
Homocol (Bayer)
Pericol (Bayer)
Isocol (Bayer)

With the exception of pinacyanol and pericol, all the above greatly enhance the green-yellow sensitiveness as well, and hence render the plates panchromatic, though the only dye which gives anything approaching an even sensitiveness throughout the spectrum without marked maxima and minima is homocol plus ammonia, and where ammonia can be left out of the question, I strongly recommend it, as plates treated with an isocyanine derivative plus ammonia keep indifferently, and rapidly deteriorate in color-sensitiveness."

holmburgers said:

This table is reproduced from Hans Bjelkhagen's Silver-Halide Recording Materials: For Holography and Their Processing. Available on Google Books.

In a nutshell, Lippmann used cyanine & chinoline red, Vatenta used cyanine & erythrosine, and Ives used isocol, erythrosine & pinacyanol.

also...

Pinacyanol (1:1000 alcoholic solution) 4mL
Orthocrom T (1:1000 alcoholic solution) 4mL
Acridine orange (1:500 alcoholic solution) 4mL

The particular sensitizing dyes mentioned above and their combinations were discovered and used by H. Lehmann to produce the best correct-color sensitivity ever achieved in Lippmann photography. However, he kept secret his good formula for Lippmann plates and it was not revealed until after his death. If one wants to try this old photographic technique today, these dyes are definitely the first choice. (emphasis mine)

Click to expand...

Hi Chris
When I was doing holograms I used eosin (aniline red) for green lasers, methylene blue for red, and glycerin for the electron donor in gelatin. I tried acridine orange, but don't remember anything special with it.(I think they came out violet) It also has to be washed out of the plate with alcohol,water alone won't do it.After coating they were dried out,and dipped in ascorbic acid to sensitize and let dry over night before use. They were not light sensitive until after the dip
Some really funny things happened with those holograms
If you can get the book do so . It is a gold mine of info,except I get lost when he sorts out what the types of bleaches are used for
rob

1,1'Diethyl-2,2'-dicarbocyanine Iodide from the OP list is available at Sigma Aldrich

Is there a difference between 1,1'-diethyl-4,4'-carbocyanine with iodine vs bromine vs chlorine?

Yes, there is.

You should not use the Iodide salt with a bromide or chloride emulsion. You should not use a bromide salt with a chloride emulsion. There are rules for counter ions when making emulsions.

PE

What kind of emulsion would you use an iodide form cyanine dye with? There are a number of them on the list of common Eastman chemical sensitizing dyes.

Denise;

A Br/I emulsion with a percentage of the Iodide on the surface would work well with the Iodide salt of a Cyanine dye. This pretty much includes most of today's modern emulsions.

PE