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Mustafa Umut Sarac
05-23-2007, 07:20 PM
Do anyone knows how to make black and white polaroid film ? They are extremelly expensive for me and it would be great fun to prepare their emulsions and experiment with them.

Best ,

Mustafa Umut Sarac

htmlguru4242
05-24-2007, 08:20 AM
When you say "Polaroid", I'm assuming that you're referring to an "instant" film that can be developed on the spot.

I agree that that would be really cool. but I'd imagine it would be incredibly difficult, especially for a positive emulsion.

I experimented with "instant" developing stuff once, using resin-coated paper as the photosensitive material. I'd discovered earlier, accidentally, that a sodium hydroxide solution would result in incredibly rapid development of the image on the paper; I assumed this was due to the incorporated developer interacting with the NaOH and water.

I made a mixture of water and sodium hydroxide, and something to make it into a paste (I do not recall what it was). I sealed this into a pod at the end of a paper and plastic setup that I made, put it in a camera, took a picture, and ran the whole thing through a set of rollers (my old old Kodak instant camera). After about 30-40 seconds, an image was visible, though obviously not fixed.

I'd think that something like that could be done with your own developer-incorporated emulsion, but its just an idea. There's still the issue of fixing the image ...

Mustafa Umut Sarac
05-24-2007, 11:56 AM
It is funny to learn to dublicate the chemical recipes of Polaroid. I am an archaeologist and I prefer to analyse a culture with its original methods.
If I am not wrong , they call it industrial archaeology. I want a print very similar to ansel adams prints from 60 years ago.
As you know after 200 years , there will be men who will want to learn these recipes.
We have to document them before polaroid off.
And
I am sorry about small format positive negative bw polaroid film. They say , it was hard to find the necessary chemicals.
Lets list :
We want same recipe Ansel Adams used.
We want same recipe with BW PN Polaroid film.
I am sure there are papers about it. I looked to us patent office and there are registered 3000 patents on polaroid. There was 3 patents on Edwin Land.
There are many patents on manufacturing special chemicals.
May be moderator can help ,

Best ,

Mustafa Umut Sarac

Photo Engineer
05-24-2007, 12:33 PM
The polaroid developer is in a pod that contains a thickener, carboxy methyl cellulose or the equivalent, and sodium or potassium hydroxide at a pH of about 12 - 14. I don't know the rest of the ingredients, but one of them is a silver halide solvent to assist in nucleation and formation of the positive image from the negative original.

This is probably spelled out in the original patents by Land.

PE

Mustafa Umut Sarac
05-25-2007, 10:09 AM
Polaroid Company gave their archives to Harvard and I sent a mail regarding correspondance between Ansel Adams and the company.
I am looking for an individual researcher who will research in the lab documents. I do not like university archives or foundation archives. Generally , there are no university staff for research and they invite you to do everything yourself. This can be seen at Rolls Royce , Frank Lloyd Wright Foundation and Getty Archives. Generally there are millions of microfiches and individual researchers want 50 dollars per 50 pages. I looked to polaroid company web site and there is even no e mail address of company for to ask pn 55 formula or its location in the archives.
I read these developers contains exotic chemicals .But I hope I find them at aldrich catalog.
It is very exciting to learn the comments of AA on a print If there is polaroid prints traffic between AA and polaroid. By this way , it will explain what he was thinking on a print , emulsion or developer at research and development stage. And it is interesting to read how polaroid staff reacts to these messages with chemical mixes.
Well , it will take time and money but it worths .

Best ,

Mustafa Umut Sarac

Photo Engineer
05-25-2007, 12:15 PM
Go to the US patent web site and search for polaroid patents granted to Edwin Land, or use www.freepatentsonline.com for searches.

A google search might start you off, as well as searches of SPSE journals where Edwin Land published first. I have read some of his papers and heard him speak on this. Also, George Eastman House has this sort of thing in their archives.

A more 'concentrated' source exists at GEH.

PE

htmlguru4242
05-25-2007, 01:18 PM
If you're going to be browsing through old (pre ~1970) patents, patent to PDF is an indispensible tool. Otherwise, you're going to be going [very slowly] through really really really large TIFF images.

http://www.pat2pdf.org/

Emulsion
05-25-2007, 04:30 PM
Another patent search tool with familiar interface is the new Google one available at:

http://www.google.com/patents

Three key advantages (over the .gov site) I have found are:
-Can easily save as a .pdf
-No .Tiff plugin is required
-Searching before the 1970's is now very easy!

AgX
05-25-2007, 06:21 PM
Mustafa,

The Polaroid processes are diffusing processes. Colour dyes migrating in their colour materials (with exception of that grid system); Silver salts migrating in their B&W processes.

The latter is the more modern version of what is called over here Silver-Salt-Diffusion-Processes and employed in several instant processes. The basic ideas were gained in 1940 by Agfa and Gevaert R&D people (Weyde/Rott) independently of each other. (Thus decennias before their merger.) As far as I remember a developed but unfixed paper by accident coming in contact with fixing agent and another plain paper formed the initial cause for further research in on case.

In the Polaroid B&W process a heavy metal plays a significant role in the recipient in reducing the silver migrated as salt from the unexposed parts of the developed negative.

It’s quite annoying doing this APUG thing without sufficient literature at hand. Besides those patents most of it is written in Dutch or German.
But in case you are seriously interested, pm me and the next time I’ll dive into those boxes of mine filled with books, I’ll try to find something of interest to you.

AgX
05-26-2007, 02:28 AM
I sealed this into a pod at the end of a paper and plastic setup that I made,...

How did you manage to make pods that burst the right way, not producing a great mess?
Actually, you didn’t state that they did not…

htmlguru4242
05-26-2007, 10:41 AM
HAHA. The pods breaking did make a bit of a mess!

I never said it worked well ... :-P


What you said, AgX, is very interesting about the unfixed sheet, paper, and fixing agent. When you say plain paper, do you mean plain regular paper or plain photo paper?

AgX
05-27-2007, 04:13 AM
When writing `plain´ I knew that such a question would arise...
Actually, I don't know. The story was about some junk stuff left about. Most probably some merely developed stuff coming into contact coating to coating with photo paper containing wet fixer. Some mess anyway, delivering intriguing results the next morning. When I got hold of the real story I shall post it.

Mustafa Umut Sarac
06-19-2007, 11:01 AM
AgX , Did you try your own way of instant photography ? Is result positive ?
Can you write more ?
I contacted with George eastman House and their chemicals history responsible said that there are no paper on chemistry of polaroid at GEH and he says chemicals are secret !
I wrote to Harvard on their polaroid archives but no reply ! I will write again

Best ,

Mustafa Umut Sarac

AgX
06-19-2007, 02:04 PM
Mustafa, no I did not forget you. But the results, a lot of printed paper but nothing substantial, were so that I hoped to get more; in vain. All I know I'll post within the next 24h.

htmlguru4242
06-19-2007, 08:01 PM
That'll be interesting. I'd forgotten about this topic, but it is interesting!

Let's hear it AgX!

Mustafa Umut Sarac
06-20-2007, 08:26 PM
I recieved a mail from Harvard Baker Library which secure polaroid archives. They say , first portion of the archives will be opened to the researchers at autumn. They will be administrive stuff.
I had been asked the correspondabce between AA and Land , and they said letters are not at Baker but still at polaroid.
I asked also PN 55 chemical recipes and the availability of them and answer will come.

Emulsion
06-21-2007, 02:18 AM
Using the google patents site take a look at the following patents:

2686716
2565378

http://www.google.com/patents

AgX
06-21-2007, 08:50 AM
htmlguru,

The encounter with those two papers leading to the Gevaert instant imaging system I hinted at above could only be traced back by me to this quotation:
“In 1938, André Rott, Gevaert R&D, observed a positive image on a baryta-coated base by the transfer of silver from a negative.”
This is far less accidental than I stated before. But, in case of a planned experiment, wouldn’t it be more apt to employ transparent film (with nuclei)? However it could be that outfixed paper still contains enough apt nuclei to let migrating halide form an image at the presence of developer…
(I’ve got a reproduction of one his results, looks a bit like lift-off transfer… A reproduction of an Edith Weyde result looks more like that accidental image transfer…)



Obtaining reversal images:

Land refers to 4 principle ways to gain a reversal picture:
-) exhausted developer (eg. Polacolor)
-) oxidized developer (eg. Cibachrome)
-) soluble silver complex (eg. Polapan)
-) coupler (which is rather a variation of the above)

-) I would add the Waterhouse reversal process
where a standard process competes with a fogging process. The bromide released by the initial development which should start at the exoposed halides hampers fogging. Thus development of the unexposed and unrestraintely fogged areas should prevale.




The Polaroid techniques can all be classified under,

`Image Diffusion Transfer´ or `Diffusion Transfer Reversal´



The B&W
process is based on the subsystem of

`Silver-Halide-Diffusion´

The idea behind it is to produce a negative, dissolve the remaining halide, letting it migrate into a receptive layer, preparing it for development, developing it and gaining a positive on this second layer.
For these processes often a mono-bath is used containing the developing agent, alkali and a halide solvent. The developing agent and the solvent can even be incorporated in the negative emulsion.

This technique makes for the second development use of a variant of solution-physical-development. Its more known counterpart, the chemical development, means that, starting from a nucleus caused by radiation exposure (or fogging), a reducing agent transfers all the silver-ions in that grain! into metallic silver. The solution-physical-development, however, means reducing nuclei after the very grain has already been greatly dissolved by a subtle halide dissolving agent. The resting silver is thus not longer delivered from the grain directly, but from the dissolved halide. (The name is due to a wrong theory on the kind of silver precipitation.)
In the silver-halide-diffusion process there are of course no nuclei, as the halides are originating from unexposed image areas. In order to make them developable in the receiving sheet fine spread metallic particles are incorporated which will form nuclei with the diffusing halides. Thus a solution-physical-development can take place.

Images made out of diffused silver have higher covering power than images originating of directly developed, which means less silver has to employed for the final image.


The Polaroid technique added to this all the feature of instant development
(fast, chemicals in pods etc., later even self-controlled with SX-70).


The history behind the silver-halide-diffusion

1857 B. Lefévre
1898 R.D. Liesegang
1938 André Rott (Gevaert) B.P. 614,155 / 1939
1941 first commercial product ( “Transargo”, Gevaert)(two sheets)
1941 Edith Weyde (I.G. Farben /Agfa) D.R.P. 887,733 and US Pat. 2,875,052 (noble metals as nuclei)
4 mono-sheet processes (The receptive layer is positioned between the base and the negative; after development the obsolete negative layer is taken off.):
1942 air-reconnaissance film, Agfa
1942 “Veriflex”, Agfa
1947 “Diaversal”, Gevaert
1947(?) “Contargo”, Gevaert
1947 André Rott (Gevaert) US P. 2,665,986 1947 (where he describes silver-halide-diffusion yielding mono- and tri-chromatic positive images)
1947 Edwin H. Land (Polaroid) US P. 2,698,238 (lead sulphide, cadmium, lead and zinc salts as nuclei) this patent can be used as cooking book. In the Neblette, 7ed. Land describes a lot of the problems he had to overcome in precipitating the silver.


(Off topic: Image transfers based on migrating developing agent have been described 1898 and 1922)





The Colour
processes fall in two categories:

The Polachrome
is just a variation on the silver-halide-diffusion mono-sheet process combined with a filter screen

It employs a panchromatic layer coated on a linear additive screen. It lacks a separate receptive layer; but this layer is coated between the screen and the negative. For processing a second film strip is laid against the first film with processing chemicals being spread between them. After processing and forming of a positive image behind the screen by those migrated and developed halides, the second film is torn off and takes with it the obsolete negative sticking to it.

(The Polavision
seems to have been the same process however the negative is said to be left in place but to be bleached out somehow(?))


The Polacolor
is a dye-diffusion two-sheet technique

A developing agent fixed to the very layer is employed, with a dye coupled to it. Being of a colour complementary to the colour the adjacent halide layer is sensitive to. This agent being oxidised, after reducing the exposed halide, has become soluble and migrates with its attached dye into the receptive layer, where they are fixed to form an image in the kind of the imbibition technique.
The developing agent is Hydroquinone which is soluble in alkali but oxidises to quinone which is insoluble. In common development processes the latter is overcome by the presence of sulphite. This is lacking in the Polacolor process. The addition of the dye does not change these characteristics. To avoid diffusion of the hydroquinone-dye couple into neighbouring layers the moment the alkali is brought upon, spacing layers are employed.

However, in the literature it is not stated how it is overcome that those dyes do not form a filter layer which would spoil the exposure of the three light sensitive layers.


The integral films SX-70 etc.
employ a dye-diffusion mono-sheet technique

In contrast to the other mono-sheet techniques the negative remains and is not bleached either. In principle it is based on the Polacolor process. The negative emulsion is coated onto a black base, the receptive layer is transparent. To avoid post-exposure when outside the camera for development, a TiO2 layer is squeezed between the layers with the chemicals. It will form the optical base for the image. As there is no parting of the layers it must be self-controlled.





Just prior to uploading I found a hint at a book I never had in my hand, nor was it referred to in the literature I got (actually I just realized I overlooked the hint in the Neblette)…:
Photographic Silver Halide Diffusion Processes
by Rott / Weyde, 302 pages, Focal Press (1972), ISBN-10: 0240507266, ISBN-13: 978-0240507262

Photo Engineer
06-21-2007, 09:23 AM
AgX;

This has an error in it:

"A developing agent fixed to the very layer is employed, with a dye coupled to it. Being of a colour complementary to the colour the adjacent halide layer is sensitive to. This agent being oxidised, after reducing the exposed halide, has become soluble and migrates with its attached dye into the receptive layer, where they are fixed to form an image in the kind of the imbibition technique."

Where development takes place, the "dye developer" becomes INSOLUABLE due to becoming a quinone. It therefore migrates where there is NO development which thereby forms a positive image in dye.

So, that paragraph is sort of backwards.

There are many more methods of producing B&W and color images by using transfers. This includes a whole series of Kodak patents among others.

Also missing is the fact that after he invented the color material, Land could not get it to work properly and turned to Kodak to develop it under contract. After that, Kodak produced it in their own plant in Rochester until Land could build his own coating machines.

After that, Kodak went on to invent a whole series of instant imaging systems including the ones that were sold, and which used direct reversal images. I've mentioned before that when I left the project, the labs were working on an ISO 3000 instant product with outstanding dye stability.

PE

AgX
06-21-2007, 10:46 AM
Yes, PE.


When I saw you being the first to reply I knew something must have gone terribly wrong...

I had trouble with spelling `unsoluble´... somehow while doing a last spelling correction the prefix must have been lost unnoticed.

Luckily enough the rest of the text indicates that there must be a sort of error in this sentence.


Furthermore, Mustafa asked for hints on doing it, so i tried to go not into detail too much and if so to refer to early work.

Please be kind; this compilation of facts was many hours of work.