I Put My Images Where My Mouth Is

Hello to All,
For Some time now, I have been blabing on this Forum that I am working on a Silver-Halide emulsion without gelatin. I have now solved the last known problem with my formuls, which was bubbles upon drying.
First, I must apologize for the fact that I can not disclose the nature of the "gelatin substitute", as it is covered by a Confidentiality Agreement which I have with a company which, I hope, will manufacture and market it. Also, there is a processing step in the making of the actual emulsion that I will, for now, keep confidential.
I will mention the following:
1) This is a glass negative emulsion.
2)The emulsion contains no animal or plant derivatives,such as gelatin,gums or startches.
3) The emulsion is an Ag/Br/I emulsion
4) Once the "gelatin substitute" is in hand, the emulsion is VERY simple and easy to make.
5) Without S or Au sensitizers the ISO is 40. With S and Au sensitizers the ISO is about 320.
6)The images I have attached are blue sensitive only. Making an Ortho Emulsion is easily done with adition of the green sensitive emulsion that PE has recommended, SDE3006. Or,alternatively, I could have added erythrosine prior to percipitation. All this is not speculation. I have actualy done these things with earlier makes of the same formula. Within the next couple of days, I will post images of the faster emulstion and of the ortho emulsion.
7) The emulsion looks and coats much like a silver/gelatin emulsion,EXCEPT that it dosn't set-up like gelatin. It must actualy dry in the dark. This takes about 3 to 8 hours with hardener, which is glyoxal.
Bill

Nice mouth!

I look forward to more!

Rockin!

Bill,

Great work!

Can you tell the group how you achieved such a high speed emulsion or is this related to the gelatin substitute?

Emulsion

Great work Bill. Congratulations.

PE

Exciting!

Bill,

Why does your first example plate remind me so much of this??



Ken

Great stuff, Bill!

Of course I make prints with gelatin, but no silver, but I don't think it would work well in-camera!

Vaughn

Emulsion said:

Bill,

Great work!

Can you tell the group how you achieved such a high speed emulsion or is this related to the gelatin substitute?

Emulsion

Click to expand...

I can tell you part of it now. The other part, I will discuss with my counterpart on the "other side" of the Confidentiality Agreement".
For S/Au senitization, I use Steigmann's Solution. Not the Hypo/Au combination recommended by most modern emulsion makers. For some reason, which I do not pretend to understand, the Steigmann's has worked better with this type of emulsion. Also, I use quite a bit more than is usualy suggested.
Bill

Congratulations!

I have an OT question though, is that Little Mountain in the second photo?

I have an OT question though, is that Little Mountain in the second photo?

No. It is called Blue Mountain. There are several hills about the same size around here (San Bernardino County, CA). They are not very high. But Mount Baldy is a real mountain, about 15 miles away.

Bill;

Some questions and thoughts after the fact.

What is the iodide content?

How do you wash out excess salts? If you do not, how do you prevent crystals from forming and the surface from being tacky from the salts and surfactants (if any)?

PE

Ken Nadvornick said:

Bill,

Why does your first example plate remind me so much of this??

Ken

Click to expand...

Ken - thanks for finding that photo. I had that same feeling as you.

Ken and Kirk,
Actualy, in "real life" the two look almost identical as far as grain and color are concerned. I don`t know why #1 looks so grainy and yellow in the scan.
I "pooped-out" last night. But I will coat more plates today and scan several.
PE,
The moler ratio ratio of Ag:Br:I = 1:1.02:0.02.
One of my goals was to make an emulsion which dose not require washing. I
minimized exess Br in order to do this. Also, I forgot to mention, the emulsion contains no ammonia.
Bill

Bill;

The emulsion does contain 1 molar equivalent of Nitrate per unit volume though, which can crystallize out and also cause tackiness. This is one of the reasons I asked.

PE

PE,
This may be why the emulsion is prone to bubble upon drying, if the wet film thickness is too thick. Partcles can create bubbles. Prior to very recently, I relied on the tape thickness on the ends of my puddle pusher to controle wet film thickness. Then I purchased a wet film gauge. I found that my wet film thickness was actualy 12-14 mils, not the 7-8 mils that I had presumed. Reducing film thickness to 7-8 mils got rid of the bubbles, so far.
I will make the higher speed emulsion today, coat this afternoon and have more plates to show you tomorrow.
Bill

Bill;

After looking through my old emulsion work, I find one interesting thing. Most polymers useful for "peptizing" or making an emulsion were not best for coating it. You had to mix two polymers. One was used for making and a second polymer was added for coating. I have several Defensive Publications and Research Disclosures on this. The rest is confidential.

We also attached couplers to polymers to make color coatings.

I cannot help you with the RDs and DPs, as they cost $$ to read and copy.

In any case, useful perhaps to you.

PE

I recall PE saying something about how the quality of gelatin that's available doesn't allow for fast film speeds. A few weeks ago I remember remembering this and thinking, "well then, why not use something other than gelatin?" Good to know that someone with the ability and knowledge to use that idea thought of it first. Fantastic stuff.

You mentioned that this emulsion was coated on glass plates. Is it possible to coat the same stuff onto a film base or instead?

As stated above non-gelatine binders have been used before. Even after the period of collodion there had been attempts in the last century and one system with synthetic binder was even commercialized but was not successful.

Bill,
What is your main intention behind going the non-gelatine way?

Bill,
Perhaps I am too skeptical, but I am un-convinced.

I don't like being unpopular, but despite risking being hated by everyone, I feel the rxn here has been way too positive!

There has been a lot of work on gelatin substitutes... I have several entire volumes on the research right here, and many of them attained or claimed to attain some degree of success. The problem is how they compare to the best gelatin emulsions... at the same grain size... ease of manufacture, and their usefulness with different treatments that one may wish to subject them to..

Non-gelatin emulsions are not new. As AgX mentoned, they have even seen commercial daylight, but at least in the case I heard about, it was later discontinued due to problems that eventually surfaced.

However, I do not want to discourage you! On the contrary, I, being a vegetarian, am very interested in success in this area. The real question is how does it compare to the best gelatin emulsions that can be made.

The fact that you have entered a CA limits the usefulness of any thing you do, unless you are wildly successful... and even then, without the details of the process, I doubt I would benefit from your process.

(Yes-I know you are not doing this for my benefit. But we must look at this in the larger scheme of things... for whom is your effort going and what lasting benefit will it provide to the field?)

Again, sorry for being the sour lemon in your water glass; I hope we can still be friends.

Ray

Photo Engineer said:

I have several Defensive Publications and Research Disclosures on this. I cannot help you with the RDs and DPs, as they cost $$ to read and copy.
PE

Click to expand...

How much do they actually cost?

BTW, I checked Defensive Publications and what I saw there looked... misleading. Is the one you are thinking of related to linux?

http://www.defensivepublications.org/login.jsp?se=true

"Research Disclosures" is fairly well known, but have never tried to get a hold of one...how much does it cost to obtain them?

Does anyone know if there has ever been a challenge to their right to qualify as "proper publication"? What is their circulation? IIRC not just any form of "publicaton" is suitable.

thisismyname09 said:

I recall PE saying something about how the quality of gelatin that's available doesn't allow for fast film speeds. A few weeks ago I remember remembering this and thinking, "well then, why not use something other than gelatin?" Good to know that someone with the ability and knowledge to use that idea thought of it first. Fantastic stuff.

You mentioned that this emulsion was coated on glass plates. Is it possible to coat the same stuff onto a film base or instead?

Click to expand...

This is a misquote. Today's gelatins do allow for high film speed, but you must choose the right gelatin and add the Sulfur and Gold in the right proportions and in a separate step. In the early days of emulsion making, the sulfur was present as an impurity in gelatin and gave the speed in one concerted operation but today it is controlled and done in a separate operation.

The gelatin from the Photographers Formulary is a very highly purified bone gelatin made by Eastman Kodak for emulsion making. Other fine gelatins come from Rousselot in France and the Gelita division of Kind and Knox in the US.

PE

Ray Rogers said:

How much do they actually cost?

BTW, I checked Defensive Publications and what I saw there looked... misleading. Is the one you are thinking of related to linux?

http://www.defensivepublications.org/login.jsp?se=true

"Research Disclosures" is fairly well known, but have never tried to get a hold of one...how much does it cost to obtain them?

Does anyone know if there has ever been a challenge to their right to qualify as "proper publication"? What is their circulation? IIRC not just any form of "publicaton" is suitable.

Click to expand...

Ray;

I am not in a position to judge the merits of Research Disclosures. I know that they are an organization that will publish Research and allow others to obtain copies of the publication for a fee. Kodak used their service for years, and in several my co-inventors and I have disclosed polymeric peptizing agents and vehicles.

Defensive publications are issued by the US Patent Office. They are very difficult to obtain. They are noted by having a "T" in front of their name (IIRC). The RDs are hard to get at and you are charged, the DPs are almost impossible to find on the Patent Office web site, but they do refer to them in the advanced search.

I have no idea as to cost, as I have no interest in getting personal copies of my own work and paying for it. Sorry.

What comes to mind is the Silver Behenate thermally processed material that was offered by EK several years back. The emulsion was coated from an organic solvent using a synthetic polymer base. It was not hardened AFAIK as it never was wet processed but rather was heat processed.

PE

Photo Engineer said:

Ray;

I am not in a position to judge the merits of Research Disclosures. I know that they are an organization that will publish Research and allow others to obtain copies of the publication for a fee. Defensive publications are issued by the US Patent Office. They are very difficult to obtain. The RDs are hard to get at and you are charged....
PE

Click to expand...

Thanks...

I should try to get one just to see what it takes.

Hi AgX;Ray and thisismyname09,
...09,
I have not tried this emulsion on film. Most of my love of photography is intimately tied to glass. I will leave the film to those who are more interested in it. But I will get around to doing a few tests, just for info.
Ray and AgX,
My answere to AgX's question and to Ray's very valid points are very subjective. There probably is no great advantage to substituting synthetics for gelatin (unless you are a cow or pig). I like to know what I am working with, and my inquiries into the nature of gelatin have not satisfied my curiosity. If anyone has any refferences which adress, in a definative manner, the nature of gelatin, I am currious.
Why did I start this thread? Simply because I wanted people to know what I have been doing for all this time. There is no "Great Grand Plan". The reason that my "Gelatin Subsitute" is covered by a CA is that it is usefull for processes much less complex than emulsion making.
Ray, of course we are "still friends". Actualy, I am surprised that something like your post did not appear within an hour of my starting this thread.
Cheers,
Bill