Devon, There's a great deal of variables that you can adjust to try and get a stronger bond between the liquid light emulsion and the film base. The first step you should take is to ensure that a subbing layer (i.e. Substratum Layer) exist for the liquid light to bond to readily. Typically, these layers are composed of a tanned (hardened) gelatin which you can make and coat yourself with relative ease. However, you may find that formulating and coating your own subbing layer will make things more difficult later on in the printing/processing stage and that some alternatives may suit you more.
The best alternative to making and coating your own subbing layer is to utilize some film with a pre-existing gelatin layers such as a manufactured film stocks. So, for example, if you have any camera or print stock which has been fogged to light and is no longer useable, you can easily convert it for use in your process by fixing the film to remove all residual halides followed by rinsing and (hypo) clearing to neutralize any chemicals in the gelatin. Additionally, you can also bleach processed black & white film with a reversal bleach, rinsing and clearing afterwards, to arrive at a similar result. Finally, it should be noted that if you choose to use a camera stock, you'll need to be wary that many have a tinted base which may or may not detract from your process. If you don't have any fogged film stocks around, see if you can get some from a film lab. Otherwise, you can purchase some for the express purpose of fogging, in which case I would recommend Kodak 5363/7363 High Contrast Positive II Print Stock. As far as formulating a subbing layer for film, you can use this recipe: Distilled Water @ 55 C....................750ml Inert Gelatin.........................................5g 2% Chrome Alum Solution.................20ml Distilled Water to Make...................1 Liter Coat and dry as you would emulsion. In regards to some of the other formulas that have been mentioned, I honestly don't believe that there is a need to utilize highly specialized chemistry such as what you'll find in commercial formulas. A hardened layer of gelatin, such as the formula above, should be sufficient for acting as a subbing layer. However, if your finding that that is not enough to affectively bond the emulsion to the film stock, than you could always experiment with the addition of a solvent to react with the base to create a stronger adhesive quality. In regards to acetate bases, I would experiment with the addition of acetone to the subbing formula above (à la film splicing cement) to create a bond between the gelatin and the acetate. I'm not certain what would be the best quantity to use, so maybe start with 100ml and work your way down. Also, I would rinse the film following drying. Of course, as I mentioned before, coating your own subbing layer onto the film might make things more complicated on account of the fact that your adding more layers of hand coated gelatin -- the more times you coat gelatin onto the film, the more thick, uneven and susceptible to problems throughout the process it will become. Then again, sometimes there's a certain appeal to that... As for alternative methods to subbing layers, such as using a spray adhesive, roughing the surface of the base, or altering the base in any other way, they're generally not recommended as they will greatly reduce the clarity of the base and most likely make your images unusable in the sense of having any...referential properties. Beyond the subbing layer, there are a few more steps you can take to help the emulsion stick to the surface of the base. For example, be sure that you give your film an adequate amount of time to dry before processing. The general rule of thumb is that there shouldn't be any tackiness to the emulsion when touched with a dry hand, otherwise it's not dry enough. Depending on how thick you coat your emulsion, this could be three hours or more. Along the same lines, avoiding excessively thick coats of an emulsion is also recommended as thicker coats are much more prone to falling off the base during processing. Finally, during processing, make sure to maintain temperatures at 20 C to within 0.3 C, including your rinse baths. You can also experiment with reducing the temperature of your processing solutions. Beyond those simple additions to your process, you could also consider hardening the emulsion either prior to coating or prior to processing. When hardening prior to coating, you'll need to utilize a 2% solution (for example, 2g / 100 ml Distilled Water) of chrome alum which you would need to mix yourself (Chrome Alum can be purchased from photographers formulary). The general procedure for this method is as follows: (1) mix a minimal amount of 2% chrome alum as the solution does not keep (5ml is more than enough for 200 ml of emulsion), (2) Heat only enough emulsion as needed for coating to around 55 C (3) Add, drop by drop, the 2% solution of chrome alum to around a ratio of 2 ml per 100 ml of emulsion, stirring constantly. (4) coat immediately, do not keep excess emulsion or 2% chrome alum... It should be noted, however, that I'm not terribly familiar with the Liquid Light emulsion and that it may already contain some form of hardener. Therefore, this method of hardening may not be the best route, particularly as it may greatly change the working properties of the emulsion and make it more difficult to process affectively if done in excess. Hardening prior to development with a pre-hardener might be the better option, but it requires more chemistry than the above method. Additionally, it is also complicated by the fact that most recommended pre-hardeners utilize Formalin (i.e. Formaldehyde) which is a known carcinogen. Below are two formulas for hardeners, one being the classic Formalin pre-hardener recipe and the other being a F-5A hardener which is usually not recommended prior to development (though I'm not certain why and I don't see any reason for not using it instead)... Classic Pre-Hardener (Not Recommended; Active carcinogens): Sodium Sulfate..............................100 g/l Formalin........................................3 - 10 ml /l Sodium Carbonate.........................10 - 50 g Water to make...............................1000 ml Treat for 1 - 5 mins at the working temp then wash 3 - 5 mins. F-5A Hardener (1 Liter Stock; Dilute 1:3 for working solution): Water @ 52C.................................750.00 ml Sodium Sulfite................................75.00 g Acetic Acid, 28% solution................235.00 ml Boric acid, crystals.........................37.50 g Potassium alum, dodecahydrate......75.00 g Water to make...............................1,000.00 ml Treat for 7 minutes at working temperature. Rinse and clear prior to development. Hope this helps, - Kevin Rice pcn03031989.com processreversal.org P.S. If you haven't already read it, you should look into Silver Gelatin: A User's Guide To Liquid Emulsion by Martin Reed & Sarah Jones. It has some fairly good, practical knowledge for working with liquid emulsion and is still available for purchase from SilverPrint in the UK.
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