Carpenter's White Glue Process?

Carpenter's White Glue Process? :confused:

I just read a description of a vintage photographic print for sale. "Carpenter's White Glue Print." That's a new one on me! The print is American and from the early 40's. Anyone ever heard of the "glue process?" :confused:

Thanks,

Gene

I haven't heard of this as a direct print making technique, but white glue sensitized with dichromate is (or was) used routinely to make photographic silk screens. You coated the screen with the glue-dichromate mix, let it dry, exposed it through a coarse-screen halftone negative, washed out the unexposed resist, and printed. I suppose a gum-bichromate like printing process would be possible, using dyed or pigmented carpenters glue. Note that most carpenters glues now contain additives to reduce their solubility in water once they dry. Elmer's School Glue is an exception, and it seems to be similar to the old white carpenters glue.

nworth said:

I haven't heard of this as a direct print making technique, but white glue sensitized with dichromate is (or was) used routinely to make photographic silk screens. You coated the screen with the glue-dichromate mix, let it dry, exposed it through a coarse-screen halftone negative, washed out the unexposed resist, and printed. I suppose a gum-bichromate like printing process would be possible, using dyed or pigmented carpenters glue. Note that most carpenters glues now contain additives to reduce their solubility in water once they dry. Elmer's School Glue is an exception, and it seems to be similar to the old white carpenters glue.

Click to expand...

That sounds kind of cool. I might want to try that some day.

I too have come across white PVA glue sensitised with potassium dichromate as a screen printing emulsion. I have the details in a book somewhere. It is contact exposed using UV light and creates clear areas in the screen where the film was black and solid areas where the film was clear so that once printed, a positive image is formed. I think it is developed/hardened in a sodium bicarbonate solution and then the un-exposed areas are washed out in running water.
This process is suitable for solvent based or water based inks as it is waterproof. It is removed from the screen with household bleach.

If it were adapted to pictorial use, it would be very high contrast as it is intended to be either solid or clear so the suggestion of using a halftone screen is good. As I recall, it is a light purple colour so additional pigment may be needed to contrast against the paper it is coated on.


Steve.

Gene_Laughter said:

Carpenter's White Glue Process? :confused:

I just read a description of a vintage photographic print for sale. "Carpenter's White Glue Print." That's a new one on me! The print is American and from the early 40's. Anyone ever heard of the "glue process?" :confused:

Thanks,

Gene

Click to expand...

Gene,

You appear to have found a kill-thread mechanism. That could be useful to have at times!!

The only thing that comes to mind is that white glue has sometimes been recommended as a substitute for gum arabic in the gum bichromate, or direct carbon process. I played around with this myself many years ago, using plain white glue. This stuff is not waterproof, which I guess is what lets it work like other colloids.

I am not an avid gummist but in following discussions on the subject I have noticed that folks are using a wide variety of substances (polyvinyl, gloy, white glue, tempera, etc.) other than pure gum arabic in processes which they continue to call gum.

Sandy King

Isn't white glue made from casein? There is a casein print process - I believe I've read about it on the unblinking eye - or maybe here.
juan

PVAc

juan said:

Isn't white glue made from casein? There is a casein print process - I believe I've read about it on the unblinking eye - or maybe here.
juan

Click to expand...

No, Carpenter's White Glue was/is made with polyvinyl acetate. See:

http://en.wikipedia.org/wiki/Carpenter's_glue
http://en.wikipedia.org/wiki/Polyvinyl_acetate

Regards,
Loris.

Well, this link shows Elmer's glue (white glue) to be a casein glue- "Casein is a milk-cheese phosphoprotein." Although there are other references that say Elmer's is no longer made from casein.

Here's an (there was a url link here which no longer exists)on casein printing.

Perhaps your old reference was to a time when the glue was still made of casein.
juan

I've just found an email I once received from someone at Elmer's products, so I've asked her if Elmer's is casein - or what she might know about casein glues. I'll post when she answers.
juan

You can take a look at the "glue print" here:

http://tinyurl.com/2672wn

Gene

Man, those folks at Elmer's are quick - here's the reply

"Elmer's Glue-All is not (and never was) made from casein. It is a compounded synthetic latex based glue. It is mainly polyvinyl acetate (PVA) resin dispersed in water and some soluble polyvinyl alcohol (PVOH). PVA polymer is made from vinyl/acetate monomer that can be manufactured from acetylene and acetic acid. Acetylene can be processed from natural gas or petroleum feedstock and acetic acid from the fermentation of alcohol. The viscosity is built in with a water-soluble thickener. The white color is due to the PVA resin particles dispersed in the liquid, which is water."

There goes that theory, so far as Elmer's is concerned.

The print at Gene's link certainly looks a lot like the casein prints on the unblinkingeye link I gave earlier. It's an interesting mystery.
juan

I think Carpenters White glue, and Elmers glue-all are two different products that are used for the same gluing applications.

I went to a now defunct trade school for silkscreen and photo-offset in the 1980's called the Manhattan School of Printing. That was indeed the method used, BUT supposedly Elmers put additives in it that can mess things up. The chemical we used to sensitize the emulsion was sodium bichromate BUT dichromate works too the latter of the two is definitely carcinogenic. I can't find a chemical supplier who has it, been looking the past couple of days. The costs are pennies to the dollar as far as buying kits like Hunt Speedball make, the kits are great but pricey. The screens were stripped with a bleach / water solution in a photographic tray.
Dead Link Removed is my site, I blog about my adventures in printing. I love this Forum, great info!

Lukas Werth is an APUG member who makes wonderful casein prints, if you're interested. He also has a nice collection on Flickr. His process was also written about in one of the Post Factory Journals several years ago...