Cleaning Film and Film Cleaners
Rx for Film Cleaning and Lubrication:
How often? Most importantly, don't over clean! Many
collectors become positively paranoid about cleaning their films.
Their compulsive efforts are better directed to keeping the
projector and it's film gate clean. Barring unusual
circumstances, once a film is cleaned it need not be cleaned for
several years. Over cleaning is trauma to film. Too much film
chemical will soften tape splices and discolor plastic reels. Use
chemical sparingly!
What chemical?
There are currently three products on the market which
collectors will find mentioned on the Internet. FilmGuard,
VitaFilm and FilmRenew.
FilmGuard: This
product is not recommended. It was primarilly designed with the
goal of having a treated film run continuously in
commercial theaters where dirt is common and scratches typically
occur. It is little more than an oily lubricant. Its ability to clean
film is dependant
upon an accompaning roller and dry web cloth accessory attached to the
projector. Whether this product is safe for films over the long term is
not known and uncertain. It's a chemical intended for theatrical release prints
which run continuously for 4 to 8 weeks and then routinely destroyed.
Film Collectors need a product for prints
that are infrequently viewed and need storage protection over the
long term. FilmGuard was not designed for those purposes.
FilmRenew:
This product is recommended. Although it is slow to
evaporate after its application, the overall result of using FilmRenew
is positive in achieving the objectives that collectors
seek in treating a print. It does an adequate light surface cleaning
and helps to lubricate a drying print. Soaking of a print over an
extented period helps relax "curl" and "saggy bag syndrome" but
is not a cure. Users must be carefull not to use an excess amount
as it will "blotch" where excess amounts failed to
evaporate. When properly applied FilmRenew is a
good choice.
VitaFilm: This product
is recommended. The primary complaint one can raise about this
product is that the maker advertises it as a "cure" for vinegar
syndrome. Soaking of a print in VitaFIlm does help to relax
"curl" and "saggy bag syndrome". An extended soak will help
remove the VS smell, and to a certain degree retard the VS process.
However, to say that "VS" has been cured is an overstatement.
Perhaps we have an argument over defined terms. A cure is in our
opinion a complete and permanent remedy and removal of VS.
VitaFilm has not demonstrated itself to do that.
VitaFilm evaporates a bit faster than FilmRenew, but still not as good
as the old time products that the EPA no longer allows. It does an
adequate job in light surface cleaning and does help in lubricating a
drying print. VitaFilm is a good choice as long as you understand
that nothing cures VS.
For those who may want to work towards their own home brew
(not recommended), or thirst for more information on the history of
Film Cleaning chemicals, we supply the following information :
According to literature dating as far back as 1960 up to the present, Kodak says:
"One of the best solvents found to date for nonmechanized film cleaning is methyl chloroform. It has relatively low toxicity, is nonflammable, evaporates quickly, removes most varieties of film dirt, is relatively inexpensive, and has antistatic properties."*** Unfortunately, since publishing that statement (which still appears on Kodak's web site) Kodak sold its chemical business and due to potential ozone depletion, the world's environmental science community recommended a cease in the manufacturing of this solvent after 1995. Some old stock may still be found, but it is no longer readily available. It is also known as 1-1-1 Trichloroethane. If you can get trichlor don't be afraid to use it. It is not a carcinogen. However, because of its toxicity, the "CAUTION! Harmful if inhaled" is required. It evaporates very fast and does an excellent cleaning job, but use it in a well ventilated area and wear rubber gloves as it is very drying to the skin.
When methyl chloroform became scarce, many labs began and continue to us Perchlorethyline (tetrachloroethylene) as the next best choice. It's nonflamable and other than having a slightly slower evaporation time, matches trichlor's excellent cleaning and degreassing ability. It is readily available from dry cleaning supply houses, as it is the basic solvent used by dry cleaners. The U.S. Department of Health and Human Services has determined that it may reasonably be anticipated to be a carcinogen. Based on evidence from animal studies, it is thought to be capable of causing cancer in humans. It should be emphasized, however, that currently available information is not sufficient to determine whether Perchlorethyline causes cancer in humans. As of December, 1999 it costs $7 per gallon for a 5 gallon case. "Perc" should be used in a well ventilated area and wear rubber gloves.
The most readily available chemical effective for cleaning film and without cautionary warnings is Isopropyl Alcohol. This is the rubbing alcohol which you can buy cheaply in any drug store. Comparing Isopropyl Alcohol with the previous two is like comparing a Ferrari to a VW bug. It's not the excellent cleaner/degreasser like trichlor or perc and it has a much slower evaporation rate, but it does clean film nicely and without any of the cautionary warnings. Your work will take a bit longer and stickey adhesive spots will require a bit more attention, but the usual dust and dirt that film attracts cleans up nicely.****
How to clean your film: Simply use a
nice, soft, lint free cloth..... keep it moist .... fold it into
a pad and lay it on a firm surface.... using your rewinds, run
the film thru the cloth while applying light pressure on top of
the pad with your hand. Most
importantly, distance the
pad from the take up reel and run the film through the cloth
slowly enough so that the chemical evaporates off the film before
winding up on the take up reel. You
don't want it winding up wet . This would
cause the film to spot, get stuck on itself and getting damaged.
Change cloths when noticeably dirty. Check the cloth often making
sure it is not scratching film. Proceed to lubricate the film.
Lubrication
Cleaning with straight chemical effectively removes the film's
dirt and lubrication. Now the film should be put through a full
coat lubrication. If the film was not very dirty to begin with,
it is advisable not to use the straight chemical at all, but
rather use a full coat cleaner/lubrication solution applied in
the same manner as described previously.
This from Kodak***: "Many oils and waxes are not suitable for full-coat lubrication of film because they form globules or mottle instead of a smooth, uniform coating. On prints, such mottle causes flicker or random variations in density. Hence the nature of the oil or wax used, as well as the solvent used to dissolve and coat it, is of critical importance. Before it is used, any lubricant formula must be carefully tested for its temporary and permanent effects on the film. One satisfactory formula for lubrication follows:
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PE Tetrastearate |
0.59 g |
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Methyl Chloroform (inhibited)** |
1 L |
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*Kodak's chemical business was sold to Fisher Chemicals.
Pentaerythritol tetastearate is a synthetic wax powder available
under their product #AC41691-1000. 100 grams for $21.00
**Methyl Chloroform (inhibited) aka 1-1-1
trichloroethane is no longer being manufactured. Perchlorethyline
or Isopropyl
Alcohol are alternatives.
***http://www.kodak.com/country/US/en/motion/support/processing/h242/h2402_04.shtml
**** Kodak cautions against the use of any alcohol as a film cleaner stating that "some types can soften the emulsion, or the base, and can increase the risk of abrasion during the cleaning process". After five years of use the Author has failed to ever experience any such result with Isopropyl Alcohol.