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Cleaning Vinyl Records
The following article is an extract from 'The Care and Handling of
Recorded Sound Materials' by Gilles St-Laurent of the Music Division
of the National Library of Canada.
PRESERVATION OF SOUND RECORDINGS
A good definition of preservation put forward by the International
Institute for Conservation--Canadian Group and the Canadian
Association of Professional Conservators is that preservation
encompasses "all actions taken to retard deterioration of, or to
prevent damage to, cultural property. Preservation involves
controlling the environment and conditions of use, and may include
treatment in order to maintain a cultural property, as nearly as
possible, in an unchanging state."
There are essentially only three concerns to consider when handling
and storing sound recordings:
* that they be kept free of any foreign matter deposits;
* that they be kept free of any pressure that might cause deformations; and
* that they be stored in a stable, controlled environment.
FOREIGN MATTER DEPOSITS
General
Dirt can be classified into two categories:
(1) Foreign matter deposits which are not part of the original object,
such as grease from fingerprints, soot, stains, adhesives, etc. and
(2) alterations of original object material through chemical reactions
(whether internal reactions or reactions with environmental agents).
Metal corrosion products, palmitic acid from acetate discs, or a gummy
substance on tapes are examples of alteration in the state of the
original.
Dust is commonly a mixture of fragments of human skin, minute
particles of mineral or plant material, textile fibres, industrial
smoke, grease from fingerprints, and other organic and inorganic
materials. There are often salts such as sodium chloride (carried in
from sea spray or on skin fragments), and sharp gritty silica
crystals. In this chemical mixture are the spore of countless moulds,
fungi and micro-organisms which live on the organic material in the
dust (fingerprints, for example, serve as good culture media). Much of
the dirt is hygroscopic (water-attracting) and this tendency can
encourage the growth of moulds, as well as increase the corrosiveness
of salts, hydrolysis and the release of acids.
Dust (including fingerprints) will negatively affect sound recording
preservation in a number of ways:
Discs
Dust is abrasive, and combined with the pressure exerted on the groove
walls by the stylus, can permanently etch the walls worse, dust can
also be imbedded permanently into thermoplastic substances. Only a
small point of the stylus is actually making contact with the groove
walls. One and a half grams of stylus pressure on such a minute
surface translates to several tons of pressure per square inch. The
resulting drag generates enough heat that the plastic partially melts
(though not enough to deform), causing a microscopic flow around the
stylus into which dust can be embedded permanently.
To minimize foreign matter deposits
General
* Never touch the surface of a recording. Use clean, white
lintless cotton gloves and handle by the edges.
* Recordings should not, unnecessarily, be left exposed to open
air. Return items to their containers when not in use and never leave
storage containers open.
* Do not place recordings near sources of dust including paper or
cardboard dust.
* Keep the surrounding area clean. Do not consume food or
beverages in the area in which recordings are handled.
* Keep storage facilities as clean and dust-free as possible.
* The air conditioning system should be equipped with dust filtering equipment.
* Keep labelling to a minimum, but limit the placement of labels,
especially pressure sensitive labels, to the container using
conservation ink.
* Keep equipment clean, well adjusted and in good working condition.
Grooved discs
* Do not use paper or cardboard inner sleeves and do not store
records without inner sleeves.
* Use soft polyethylene inner sleeves. Do not use record sleeves made of PVC.
* Remove grooved discs from the jacket (with the inner sleeve) by
bowing the jacket open by holding it against the body and applying a
slight pressure with a hand. Pull the disc out by holding a corner of
the inner sleeve. Avoid pressing down onto the disc with the fingers
as any dust caught between the sleeve and the disc will be pressed
into the grooves.
* Remove grooved discs from the inner sleeve by bowing the inner
sleeve and letting it slip gradually into an open hand so that the
edge falls on the inside of the thumb knuckle. The middle finger
should reach for the centre label. Never reach into the sleeve.
* To hold a disc, place the thumb on the edge of the disc, and the
rest of the fingers of the same hand on the centre label for balance.
Use both hands on the edge to place disc on turntable.
Cleaning
Since dust is usually held in place by electrostatic attraction, dry
wiping on its own does not work effectively. The added friction
created by the duster will cause the dust to jump back to the charged
surface.
Distilled water is used for cleaning records and CDs for many reasons.
Its precise chemical makeup is known, it will not leave any residue
behind, is safe to use, and is inexpensive. Water disperses static
charges and counteracts the increase in conductivity from the pick-up
of salt deposits from finger prints. However, water alone cannot
dissolve grease, thus surfactants are used as additives to enable
water to be a grease solvent. Surfactants break grease surface bonds
and allow water to penetrate grease solids, causing swelling and then
random dispersion.
General
The Canadian Conservation Institute (CCI) recommends the use of
nonionic, ethelyne oxide condensates surfactants to clean sound
recordings. The CCI does not foresee long-term problems associated
with the use of nonionic surfactants such as Tergitol. Tergitol 15-S-3
is an oil soluble surfactant and 15-S-9 is a water soluble surfactant.
Combined they remove a wide range of dirt and greases and can safely
be used on sound recordings. Use 0.25 part of Tergitol 15-S-3 and 0.25
parts of Tergitol 15-S-9 per 100 parts of distilled water. (These
products are available in small quantities from TALAS (Division of
Technical Library Service Inc) 213 West 35th Street, New York, N.Y.
(212) 465-8722.) The recording must then be rinsed thoroughly with
distilled water to eliminate any trace of detergent residue. Keep an
airgun handy to blow off light surface dust.
Grooved discs
Grooved discs are best cleaned using a record cleaning machine such as
the Keith Monks, VPI, Nitty Gritty using 0.25 part of Tergitol 15-S-3
and 0.25 parts of Tergitol 15-S-9 per 100 parts of distilled water.
These machines allow for an even dispersion of fluid and can then
vacuum the liquid leaving a clean, dry surface. The discs must then be
rinsed thoroughly with distilled water and vacuumed dry to eliminate
any trace of detergent residue. Records should be cleaned before each
playback.
Clean Vulcanite discs showing signs of acid build up using 0.25 part
of Tergitol 15-S-3 and 0.25 parts of Tergitol 15-S-9 per 100 parts of
distilled water and rinse thoroughly.
Clean acetate discs showing signs of palmitic acid deposits (white
greasy substance on acetate disc surface) as if cleaning LPs, except
add 1 part ammonia per 100 to the Tergitol cleaning solution. Do not
use ammonia on shellac based discs.
SURFACE DEFORMATIONS
Since the surface of a sound recording is the information carrier, it
is critical that the surface be well cared for. Physical deformations
such as warping of discs, stretching of tape or shock from dropping
them, will directly affect sound information integrity. One must
develop a respect for the integrity of the artifact.
To minimize deformations
General
* Never leave recordings near sources of heat or light (especially
ultraviolet light) as plastics are adversely affected by both.
* Do not place heavy objects on top of recordings. Recordings
should never be placed on top of each other.
* Shelve recordings vertically; do not stack "off vertical" or horizontally.
* Do not use shelving units where supports put more pressure on
one area of the recording or where supports are more than four to six
inches apart.
* Do not interfile recordings of different sizes as smaller items
may get lost or damaged, while larger items may be subjected to uneven
pressure.
Discs
Remove shrink-wrap on LPs completely. Shrink-wrap can continue to
shrink, thus warping the disc. |
