Bonding film to glass

[Stefan Findel]

I would like to bond ('glue') film (preferably the emulsion side) to glass in an archival and permanent way. The bonding material must be optically clear (invisible) and in no way interfere with viewing the image on the film when seen through the glass and bond.

Does anyone have professional experience with this or insight into how this could be done?

Stefan

 

[Ian Grant]

Try Balsam cement as used for Microscope slides & pre-70's Optical elements in lenses.

I did many hundred microscope slides but not glass to film or glass to glass yet

Ian

 

[richard ide]

For what purpose do you wish to do this? I have mounted various photo materials to clear acrylic using both a clear double coated adhesive film and silicone adhesive. Canada Balsam is a good idea but my only reservation would be that the layer may be thicker than used in microscopy or cementing lenses and as the essential oil evaporates, might allow air bubbles to form.

 

[Stefan Findel]

Ian and Richard, thank you for replying. The purpose is to give more flatness and stability to the film I use, which is an Arista orthochromatic film, and thinner than standard camera film. I am printing on this film to make orotones, i.e. the other side is surfaced with gold (using gilder's oil as bonding medium). For handling and framing it would be good to bond the film to glass. I have not been succesful coating emulsions to glass, nor am I aware of coatable orthochromatic emulsions, so printing on Arista has been a good alternative so far. Maybe too, I could use that same gilder's oil to bond the film to glass. I didn't try that yet. I am not really aware of what Canada Balsam is and have to look into that.
Thanks again.
Stefan

 

[richard ide]

Would it be possible to just sandwich the film between two sheets of glass and apply the gold leaf and size to the inside surface of the back sheet of glass or the back of the film. When I was mounting film and paper, I had a very expensive learning curve.

 

[Stefan Findel]

I thought of that, but wonder about the archival aspects like humidity getting into the sandwich and possibly Newton rings forming.
The more I read about Canada balsam the more curious I get, and wonder if I can use it to also bond the gold to the film. I will be in Germany over the Holidays and want to approach the gold leaf company where I get my supplies and get their thoughts on this.
I wonder where I can find out about the PH of Canada Balsam and the Gold Leaf sizing.
Thanks guys,
Stefan

 

[Christopher Walrath]

How about preheating the glass and then pressing the film onto it while warm enough to cause the gelatin to semi 'melt' (?) and thus bond to the glass? Never done it but to the unknowing it kinda makes sense. I would try it anyway to see if it worked.

 

[Stefan Findel]

Yes, mh, maybe. And you're giving me an idea, like pressing the film onto glass while the gelatin is still wet. With the glass preheated.

 

[Christopher Walrath]

Can't risk chemical reactions from the one direction, work something out the other way, huh? Let us know what you get going. Might wanna try a variant myself.

 

[David A. Goldfarb]

I would think there would be a UV-cured adhesive like what is used to cement lens elements that would work. These adhesives are also used in auto glass. They are optically clear and completely repositionable until they are cured with UV light, but I don't know how they would bond with or interact with film.

Ron Mowrey's Azo-like silver chloride emulsion is available now from Photographer's Formulary, and I believe it will bond to glass that has been subbed with gelatin--

http://www.photoformulary.com/Deskt...0&selection=0&langId=0&Search=liquid emulsion

 

[Mark Fisher]

UV adhesive was my thought also. It is used in the assembly of medical disposables also. Once you position it and get rid of the bubbles, you would zap it with UV light. Loctite makes a number of them. I'd take a look at the Edmund Optics catalog as see what sort of adhesives they offer for optical bonding.

The other thing that might be worth considering is coating the glass with hardened gelatin as David suggests. The wet and submerge both the glass and the negative. Once the gelatin is nicely swelled and all bubbles are worked out, lift the assembly out of the water then press the two together. I would think that this will be easier than any adhesive. Keeping things neat and clean doesn't go well with handling adhesives.

 

[David A. Goldfarb]

My suggestion regarding the gelatin wasn't for bonding film to glass, but it might work. Formazo is a liquid emulsion that might bond directly to glass subbed with gelatin, making it possible to print directly on the sensitized glass.

 

[Stefan Findel]

I actually took Ron's emulsion making class and already asked his advice. I do like the ortho film I use because of how it sepia tones.
BUT I may have to give glass coating another try... My initial attempts were laughable, with the emulsion floating off with a wicked grin - just as I thought I had reached the end of the final wash...
(Probably should specialize on emulsion transfer, already know how to get it off.)

 

[Christopher Walrath]

See, play to your strengths. Attaboy.

 

[richard ide]

Having used both I make the following to consider and take in to account. Canada Balsam hardens by evaporation of the essential oil and takes a while. The % essential oil is relatively small IIRC perhaps around 15%. Gold size is like a varnish with probably well over 60% volatile solvents. For it's intended use, you apply it and wait until almost all of the solvent evaporates before applying the gold leaf. I think it might be prone to bubbles if used wet for mounting.

 

[paul_c5x4]

The gold size I've been using (from C. Roberson & Co) is a PVA solution. Works fine when used behind gold leaf for stuff like picture frames. When used on glass, it shows up every single spot of dust and bubble and you have to get the leaf down perfect first time if you are to avoid any creases or wrinkles.
I found a gelatin size to be much easier to work with - Two or three diamonds of gelatine in about 300ml water - Liberally brush on to the glass, pick up a square of leaf with a gilder's tip (don't use the stuff on backing paper). As you bring the leaf close to the wet glass, it will appear to jump on to the glass. The working area being wet, you have the chance to move the leaf around a little to get rid of creases and work any air bubbles out.

How easy is it -- [YOUTUBE]http://www.youtube.com/watch?v=4-eW6sxhli0[/YOUTUBE]

 

[Stefan Findel]

Wow, this is getting better and better. Thank you Paul for that video. I had initially used gelatin but without applying the gold the way it is shown here. I had never seen or heard of that particular tip used to apply the leaf. And if I can attach the film to the glass using gelatin sizing, it will be easy to move it around to position it perfectly on the glass.

 

[richard ide]

FYI trivia slightly off topic but related. Gold leaf is the thinnest material available and is not machine made. 200,000 sheets per inch. you can also see through it (green).

 

[rmolson]

Too bad they no longer make graphic arts strip film. Back in the days even before my time lith film was soaked and slide off the base onto glass plates It was sized and cut down and positioned in page position with text which later was burned to printing plates Using strip film is where the term "Stripper" for any one who combined text and images together for printing in graphic arts came from. Not taking off our clothes suggestively.

 

[paul_c5x4]

BUT I may have to give glass coating another try... My initial attempts were laughable, with the emulsion floating off with a wicked grin - just as I thought I had reached the end of the final wash...

Using a subbing layer usually avoids the problem of the emulsion lifting off during the wash - Ideally, you want to use a subbing layer containing chrome alum.

Most of my own attempts at coating glass with an emulsion have been less than perfect. Over the holiday period, I want to have a o at constructing a spin coating machine - Hopefully, it will be a little more repeatable and consistant than rod coating.