Note: Descriptions are shown in the official language in which they were submitted.
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PROTECTIVE CO~OS ITIONS FOR RECORDING
T~e present invention relatea.generally to
lubrication of substrates and, more particularly, to an
impro~ed lubrication composition and method of its.
application. The improved, wear-resistant, low friction
5 s.ubstrates have a coating provided by such composition, :
. :, ..
~aid su~strates: including sound and video recordings such
: as. gramophone or phonographic records, video discs and
the like.
Lubrication of various substrates, and
lQ particularly of substrates upon which recorded signals
have ~een stored and from w.hich said signals can be
recalled by dynamic means, has not been generally re-
co~ni7ed and where attempts have been made to
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lubricate such.substrates they have not proven fully
satis.factory. In particular, substrates possessing this
special pro~Iem include synthétic, natural and combinations
of the thermoplastic materials and include resins ,- shellac;
polyvinly aceta:te, polyvinyl chloride, cellulose .acetate,
poly (methyl methacrylatej, cellulose nitrate:and their
deriyatives as. weLl as numerous other compositions that
are generally formed through various press moulding means
into phonographic records or discs as weIl as similar
thermoplastic s:tructures. having trackable groove contours
and reproaucing recorded monaural and stereophonic and
video signals therefrom.
As is generally known, a phonograph cartridge
serves to convert th~ variations on the ~alls and/or
bo.ttom of.~he grooves of a phonograph:xecord into.
electrical signali whereby
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the variations or wavy pattern on the grooves determine the
frequency and the amplitude of the sound vibrations. The
cartridge includes a stylus or picku~ needle usually in the
form of a diamond or sapphire which generally as a hemi-
spherical or ellipsoidal tip which rides or dips into the
record groove and moves in response to variations of the
pattern of said groove. The stylus, in turn, is generally
attached to an armature which moves with the stylus to induce
variations in an electrical or magnetic field in response to
- 10 the stylus movement. This generates an electrical signal
representative of the groove configuration which may then be
amplified and used to drive speakers. Again, the stylus is
caused to mechanically vibrate in response to the variations
in amplitude and frequency of the undulations of the record
groove wall which comprise the recorded signal.
A stylus has to track a plurality of evenly spaced
groove contours with recorded signals on the order of between
15-20 and 20,000 Hz. Moreover, with the introduction of
discrete four-channel record system or quadrasonic systems,
a stylus must faithfully track grooves with recorded signals
to cause vibrations of up to 50,000 Hz. As the stylus rides
in the record groove, the relatively hard stylus wears away
the relatively soft thermoplastic material of the record
forming the groove. There has been heretofore no easy solution
to alleviate the problem of record wear caused by the stylus
.
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riding in the groove contour of such recordings.
The deterioration of the sound quality of records
with increase in the number of plays through wear of their
tracks by repeated uses re~ults in records becoming unusable
and often being discarded within a short period of time. A
number of factors is responsible for wear including the
general wear through abrasive and adhesive wear mechanisms to
an extent proportional to stylus loading. This loading is not
only the deadweight stylus load on the record which may range
from about 1 gram to 4 grams but also includes dynamic inertial
forces caused by stylus mass and the frequency of stylus
directional changes as it tracks the groove undulations. As
.:
known, reduction of deadweight load and stylus mass lowers
the rate of groove wear but wear and the conse~uent loss of
lS playback fidelity cannot be entirely eliminated. At any rate,
most attempts of the prior art via record cleaners or alleged
lubricates have simply resulted in cleaning only or
depositing chemical ilms onto records without being
successful in that such materials generally reduce the record
2~ fidelity due to rapid groove wear if cleaned or to hydro-
dynamic damping of the stylus tracking if oily substances are
` deposited. Further, it is often observed in the use of these
materials that the noise level is increased due mainly to
dust captured along with the formation of a tacky deposit
upon the stylus. Moreover, it has been observed that attempts
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to use powdered solid lubricants such as graphitel molybdenum
disulfide and the like have several disadvantages for they do
not only reduce fidelty but also increase noise due to
- particulate interference in record grooves.
In general, various silicones and hydrocarbon waxes
and certain fluorinated telomeric compositions have been used
as lubricants in sundry applications. One example of prior
disclosure is a ethylene telomerized with trichlorotrifluoro- -
ethane whereby moderately high molecular weight products are
provided. In order to obtain a wax-like product~ a second
active telogen must be included in the telomerization process.
In general, such active telogens are hydrogen-containing
compounds including tertiary hydrocarbons~ aliphatic alcohols,
divalent sulfur compounds, aliphatic tertiary amines, aliphatic
ethers, carbonyl compounds and dialkyl phosphites. Since
these active telogens contain hydrogen, the telomer products
contain significant amounts of hydrogen, e.g. from 0.05 to
2% by weight.
Another example of prior disclosure would be
compositions~which have ~o hydrogen and are of a lower melting
point. In effect, such compositions are derived from the
product~ obtained by telomerization of tetrafluoroethylene
with cert~in haloalkanes. In fact, the compositions are made
by chlorination or fluorination of certain fractions of telomer
iodide mixtures whereby the iodine is replaced by chlorine or
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fluorine. The utility of these composition is found in their
application as a general dry lubricant, protective surface
treatment, oil and water repellants, and a mold release and
anti-stick composition.
The prior art discloses a method for renewing,
resurfacing and preserving a phonograph record by the steps
of coating the record with a composition consisting
e~sentially of acrylic polymer, polyethylene emulsion, a
detergent, an ether and water, brushing the composition into
~he grooves, removing any excess, drying and playing the
phonograph record.
Also, the prior art discloses a method, composition
and article are disclosed for improving lubricity, abra~ion
re~istance, and lowering the coefficient friction of substrates
such as photographic films, magnetic sur~acas and other
recording elements by applying to such substrates a sol~tion
comprising tetrafluoroethylene telomer and a copolymer of
vinyl chloride and trifluorochloroethylene in a volatile
~olventS drying and removing the exce~s, and substrates so
lubricated. In effect it was shown that ~he combination of a
lubricant, viz., tetrafluoroethylene telomer and nonlubricant,
viz~, poly ttrifluorochloroethylene-co-vinyl chloride)
provides a coefficient of friction ~elow that of the lubricant
per ~e.
The present invention, which provide~ a wear-
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resistant lubricous coating for photgraph records and the
like is a solution comprising essentially an ester lubricant,
and optionally a tetrafluoroethylene telomer or an an antistatic
agent, and a volatile solvent therefor. The composition can
be easily applied to any nu~ber of thermoplastic substrates
generally used in the record or gramophone trade, upon which
are recorded signals in the form of undulations or grooves,
to provide a glossy coating that promotes a marked increase
in lubrication properties thereof.
According to the present invention, a composition is formed
for imparting lubricity and wear resistance to a surface having
dynamic presentations thereon comprising about l.~Ol to about
3.000 weight percent of a composition containing a carboxylate
ester, said ester being derived from a perfluoroalkyl alcohol
of the formula CnF2n+1(CH2)mH wherein n is from about 3 to
about 14 and m is l to 3 and an aliphatic carboxyiic acid having
about 3 to 30 carbon atoms, and an antistatic a~ent selected
from the group consisting of amines, fatty ammonium compounds,
fatty acid esters, phosphate esters and ethoxylated compounds,
and about 97.00 to about 99.999 weight percent of a solvent
therefor.
The ester lubricants of the preferred embodiment to
be hereinafter described are soluble in the solvent and Eor
the most part do not exist in the composition herein contemplated
as particles or as colloidal suspensions. In effect, the
' #3
composition of the present invention is generally an
essentially homogeneous solution that is, it exhibits a
uniform composition throughout its entire volume.
The term "substrate" as used herein embraces
various surfaces of articles to be treated by the
compositions and refex to plastic suhstrates, metal substrates,
combination of plastic and metallic substrates, and in
particular to playing elements of synthetic, natural and
comhinations of thermoplastic materials and include resins,
shellac, polyvinyl esters such as polyvinyl acetate, poly-
vinyl benzene, polyvinyl chloride, cellulose acetate, po~y
(methyl methacrylate), cellulose butyrate, cellulose nitrate,
their derivatives as well as copolymers and blends thereof.
In particular, the term "substrates" include those surfaces
which are made of numerous compositions that are generally
formed through various press molding means into phonographic
records or discs as well as similar thermoplastic structures
having trackable groove contours thereon which when used in
conjunction with certain dynamic means such as styli are
capable of following said contours and repxoducing recorded
monaural and stereophonic and video signals therefrom~
The compositions herein of the subject invention
which impart to a given substrate a low coefficient of friction
comprise a solution of a carboxylate ester lubricant including
esters derived from alkalene glycol and polyoxyalkylene
.
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g
alcohols as well as esters in which the alcohol portion
thereof is derived from halogenation of an aliphatic alcohol,
especially fluoronation thereof. In general, the fluoroalkyl
esters may be esters of monocarboxylic acid, viz.~ the
fluoroalkyl monoesters; the esters of dicarboxylic acid, viz.
the fluoroalkyl diesters; esters of tricarboxyli~ acid, viz.,
the fluoroalkyl triesters; and esters of tetracarboxylic
acid, viz., the fluoroalkyl tetraesters. Herein the fluoro-
alkyl esters are compounds derived from carboxylic acids by
replacing the ionizable hydrogen atom by a fluoroalkyl radical.
The fluoroalkyl portion of the molecule is the
alcohol moiety thereof and has generally from abo~t two to
about twenty carbon atoms. The preferred fluoroalkyl mono-
carboxylic acid esters are fluoroalkyl acetate, fluoroalkyl
- 15 laurate and fluoroalkyl stearate; the preferred fluoroalkyl
dicarboxylic-acid esters are fluoroalkyl malonate and
fluoroalkyl azelate, and the preferred fluoroalk~ tri-
carboxylic acid ester is fluoroalk~l citrate. These fluoroalkyl
esters can be readily prepared by conventional chemical
techniques known in the art. In general, the fluoroalkyl
monoesters may be produced by condensation of fluoroalcohols
with aliphatic monocarboxylic acids. Further, fluoroalkyl
polyesters may also be readily produced by the reaction of
fluoroalcohols with polycarboxylic acids, either of the
aliphatic or aromatic type. Mixed esters are also readily ~-
- 10 -
produced by the reaction of fluoroalcohols with polycarboxylic
acids, ei~her of the aliphatic or aromatic type. Mixed
esters are also readily produced such as those formed from
the condensation products of pyromellitic anhydriae with a
mixture of fluoroalcohols.
The esters herein contemplated embrace those esters
of terminally fluorinated alcohols in which a bridge containing
an alkylene group is interposed between the fully fluorinated
portion and the ester linkage. It is understood that the
fluorinated alcohol may be a branched as well as a straight
chain moiety~
In particular, the fluoroalkyl esters used in
accordance with this invention may be readily prepared from
the perfluoroalkyl aliphatic alcohols (viz., 2-perfluoroalkyl
alkanols) of the formula C F2 +1(OEI2) OH where n is from
about 3 to 14 and m is 1 to 3 and the corresponding carboxylic
acid by art-known procedures. For examples, esterification
reaction may be readily carried out by using para-toluene-
sulfonic acia or sulfuric acid as a catalyst with the alcohol
and carboxylic acid in benzene and heating these ingredients,
remo~ing the water of reaction by codistilling with the
benzene and thereafter removing any residual by di~tillation
to isoLate the given esters. The perfluoroalkylethanols may
be prepared by hydrolysis of fluoroalkyl hydrogen sulfate
25 which in turn are produced from the reactions of perfluoro-
.. .. . . . . .
27~
11 --
alkylethyl iodides with oleum. Also, the perfluoroalkylethyl
iodides may be prepared by known reactions of perfluoroalkyl
iodide with ethylene as well as by known telomerization
reactions. Conventional separation techni~ues may be
employed to isolate selected fractions as, ~or example, the
corresponding iodides having the perfluoroalkyl moiety in the
range of 6 to 14 car~on atoms may be separated by dic~tillation.
~he fluoroalkyl esters may generally be mixiures
which can, if desired, be further refined by fractional
distillation or chromatographic techniques. Nonetheless, the
esters may cover a somewhat broad ranye; for example, a common
fluoroalkyl ester such as fluoroalkyl malonate may generally
be a mixture of esters having an average of about 7~/O to 80%
perfluorohexyl to perfluoroheptyl-containing esters, with
esters ha~ing a perfluorobutyl moiety and lower, less than
about 5% and a per1uorodecyl moiety and higher, making up
the balance.
The alkylane glycols used to form the carboxylate
est~rs herein include ethylene glycol, propylene glycol,
glycerol and trimethylene glycol. Further, the polyoxyalkylene
glycols used to form the carboxylate esters herein include
polyethylene glycol, polypropylene glycol, polybutylene glycol,
poly(ethylenepropylene) glycol and the like. The polyoxy-
alkylene glycols of the preferred embodiment are those that
contain 2 to 4 carbon atoms of the recurring oxyalkylene group
- 12 -
and have a molecular weight k,elow ~bout 6000 for the
polyoxyalkylene portion of the molecule.
The carboxylic ac:ids herein contemplated that form
the acid portion of the ester~ may contain rrom about 3 to 30
carbon atoms. The carboxylic acid moiety of the ester may be
aliphatic, alicyclic, aromatic or hete~cyclic and may be
saturated or may contain double bond unsaturation, such as
ethylenic unsaturation. Representative car~oxylic acids for
the esters herein contemplated are the fatty esters, both
~aturated and unsaturated and include acetic, malonic, butyric,
isovaleric,azelaic, caproic, caprylic, capric, lauric,
myristic, palmitic, palmitolic, stearic, oleic, ricinoleic,
vaccenic,linoleic, linolenic, eIeostearic, licanic, parinaric,
arachidic, gadoleic, arachidonic, behenic~ cetoleic, erucic,
lignoceric, selacholeic and cerotic acids, with lauric,
malonic, azelaicg stearic, citric, oleic and palmitic being
preferred acids.
The polyoxyalkylene glycol monoesters and polyoxy-
alkylene glycol diesters may be represented, respectively, by
the general f,ormula:
I R Q o (R-O~- H
1 n
; II R - ~ - O -~R-0~- Q - R
1 n 2
respectively,wherein R and R are alkyl radicals and R is a
1 2
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di~alent radical having 2 to 4 carbon atoms and n is an
integer from about 2 to 200. Illusl:rative of these mono-
and diesters are the following compounds: Polyethylene glycol
monostearate, polyethylene glycol distearate, polyethylene
glycol monolaurate, polyethylene glycol dilaurate, polyethylene
glycol monoleate, polyethylene glycol dioleate, polyethylene
glycol monobehenate, polyethylene glycol dibehenate, and
polyethylene glycol coco fatty acid esters.
To the compositions herein disclosed may be readily
included certain low-molecular weight telomers of fluorocarbons,
and especially telomers of tetrafluoroethylene. As used
herein, the term "telomers" includes homotelomers and
cotelomers and the term "telomerization" includes homotelo-
merization and cotelomerization and the term "low-molecular
weight telomers" means telomers having a maximum average
molecular weight of about 3700.
One group ofpreferred telomers of this invention
may be represented by the general structural formula:
R-(CF CF ) X (I)
2 2 a
wherein R is a haloalkyl containing one to four carbon atoms,
X is a member oelected from the group consisting of chlorine,
iodine, and fluorine and a is an integer from about 6 to about
16. A preferred composition of the present invention is one
where X is chlorine or fluorine and the radical R is a group
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having the structur;ll formula:
R
R - C -
F
wherein R and R each independently represent per~luoro-
alkyl and monochloroperfluoroalkyl wherei~ each alkyl moiety
has one to four carbon atoms. Th-s tetrafluoroethylene
telomer has been available commercially under the trade name
MP-51. In general, these telomers are completely halogenated
telomers, in that they do not contain hydrogen, and have a
molecular weight range of about 800 to a~ut 1800.
Other groups of related and preferred telomers are
those that ha~e the formula:
Rl(CF -CF ) y (II)
2 2 b
-; wherein R' is a hydrogen-containing moiety of a telogen,
Yaid telogen being a member selected from the group consisting
of tertiary hydrocarbons, aliphatic alcohols, divalent sulfur
compounds, aliphatic tertiary amines, aliphatic ethers,
.
: aliphatic carbonyl compounds, dialkylamides and dialkyl
: phosphites, and Y is chlorine or a chlorofluoroalkyl wherein
the alkyl portion has one to two carbon atoms and where b is
an integer from about 3 to about 50. In general, these
tetrafluoroethylene telomers, as distinguished from the
.
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telomers mentioned above, contain hydrc,gen, e.gO, from
0.05 to 2% by weight.
Hydrogen-containing tetrafluoroethylene telomers
are available under the trade mark Vydax AR. These telomexs
S have a maximum average molecular weight of about 3700, a
specific gravity of about 2.16, a melting point of 300C~,
and are generally furnished at various concentrations
including a 20% solid suspension in trichlorotrifluoroethane.
It has been found possible to separate from Vydax
AR a somewhat lower molecular weight fraction by the
conventional expedients of extracting, d~canting, filtering,
or centrifuging. By such methods, a selected fraction is
obtained where, in the above-mentioned structural formula II,
b has a value of about 3 to about 84 In general, lack of
lS turbidity or presence of clarity of the solution is found to
be a good indication of such a selected fraction. The average
molecular weight of this lower fraction is between about 400
and 900, the fraction being readily soluble in the herein
de~cribed organic solvents~ The melting point of this fraction
2~ is generally~less than 120c.
For the hydrogen-containing telomers, such as Vydax
AR, it has been found, for certain preferred embodiments that
the use of the lower molecular weight fraction, that is, the
fraction having a molecular weight helow about 900, results
in favorable properties for certain end uses herein disclosed.
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Thu8, during stylus tracking on a stereo or quadraphonic
record coated with a composi*ion of the present invention,
there is observed no substartial wear particle build-up on
the stylus as compared to an untreated record~ Further,
there is no actual clogging or interference of the groove
undulations even in a single alternation with a record at
fre~uencies up to and ind uding 45,000 ~z., which may occupy
no more than about 0.0008 linear inches of space along tha
recoxd groove.
In general, the concentration of the above-mentioned
telomer additive can vary over a relatively broad range, but
a range of about 2.0 weight percent to about 0.00~ weight
percent of the total weight of the composition has been found
most effectiva. In practice, a concentration of between about
0.15 to about 0.005 weight percent has been found to be
satisfactory for treating phonograph records.
An antistatic agent is not always required with the
compositions of this invention. It has been noted in the
course of worX that some ester lubricants do exhibit the
~0 characteristic of effectively reducing static charge on a
substrate without incorporation of a separate antistatic agent
as such~
But an antistatic agent may be used, if desired, to
render the compositions herein described more e~fective from
a practical standpoint in that such compositions having
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incorporated therein said agent elimin~te or sub~tantialLy
reduce the electrostatic charge on phonograph record
surfaces to which such compositions are applied, thereby
reducing the attractice forces which induce the migration
o~ dust and other undesirable foreign particles to the
record surface. The electrostatic charge can result from
several causes, but is especially noticeable upon removing
a record from its protective iacket, wiping its sur~ace with
cl~th or brush, and otherwise contacting or buffing the
record surface. RepresentativP of one group of preferred
antistatic agents found highly effective in the compositions
herein are the tertiary amines, including the diaIkanolamines.
These amines have been found to be compatible in terms of
solubility with the solvents herein disclosed.
The particular dialkanolamines found highly
suitable for the herein described composition may be
represented by the general structural ~ormula:
HOCH CH N CH CH OH
2 2 2 2
R"
2Q wherein R" is an alkyl having about four to about twenty
; carbons atoms. These dialkanolamines have a molecular weight
o~ about 150 to about 400. IlLustrative of such dialkanola-
mines are N,~-bis(2-hydroxyethyl) dodecylamine, N,N-bis(2-
hydroxyethyl)tetradecylamine and N,N-bis(2-hydroxyethyl)
tetradecylamine. Tha dialkanolamines may be readily made by
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conventional chemical techniques known in the art.
Other suitable and preferred antistatic agents
may be readily incorporated, if desired, into the
compositions herein. Such agents should be soluble in tha
solvent employed. Thus other antistatic agent~ include
fatty quaternary ammonium compounds, fatty esters, phosphate
esters and ethoxylated compounds. The ethoxylated compounds
include such compositions as polyethylene glycols as well
as ethoxulated triglycerides, ethoxylated sorbitol and the
like. The concentration of the antistatic agent can vary
over a wide xange so long as it is ef~ective in reducing or
removing electrostatic charge. When incorporated, a
concentration of about 1.0 to about 0.001 weight percent
based on the total composition has been found to be most
e~fective.
The solvents utilized with the compositions of the
present in~ention include organic compounds as well a~ water.
While certain solvents are useful, provided there is no
adverse effect upon the substrate, trichlorotrifluoroethane
2~ is particularly desirable as having suitable oxganic
dissolution powers, high volatility, and essentially no
physical or chemical effect on the substrate. The trichloro-
tri1uoroethane can be either isom~ex, i.e., it may be 1,1,1-
trichloro-2,2,2-trifluoroethane or 1,1,2-trichloro-1,2,2-
trifluoroethane.
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Other userul solvents of the present invention,
either individually or in mi.scible combinations, include the
following:
Alcohols Ketones Estç~.rs
5 methanol acetone ethyl acetate
ethanol methylethyl ketone propyl acetate
n-propanol methylpropyl ketone isopropyl acetate
isopropanol methylisopropyl ketone butyl acetate
isobutanol methylisobutyl ketone
diethyl ketone
ethylpropyl ketone
ethylisopropyl ketone
Haloqenated HydrocarbQns H~drocarbons Etheræ
carbon tetrachloride benzene isopropyl ether
chloroform toluene diethyl ether .
methylene chloride xylene dioxane
methyl chloroform pentane
tetrachloroethylene hexane
trichloroethylene heptane
dichloroethane octane
dichloxoethylene
perfluorodimethyl.cyclobutane
benzotrifluoride
The penetrating ability or penetration coefficient
of a given solvent is Important to obtain the proper and
effective distribution of lubricant, especially in the fine
grooves and tiny crevices of a phonograph record, media,
2d substrate or the like having dynamic presentations thereon.
For example, record grooves are generally closely spaced,
IJ-shaped crevices having an opening of about 0.003 inch
(7.6 microns) with a bottom radius of often e~ual to or less
than 0.002 inch (5.1 microns). In order to get within the
grooves of the record track the solvent itself must exhibit
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a high penetration ability, a propexty ;apparently depending
on a number of factors including surface tension ViSCQSity~
volatility, etc. Seemingly, solvents found most effective
for their purpose are those that have surface tensions of
le-s than about 20 dynes per centimetre (20C.). ~or this
reason trichlorotrifluoroethane is one desirable sol~ent.
A preferred composition of the present invention
consists of an este~ lu~ricant, an organic solvent and
optimally an antistatic agent which is, preferably, a tertiary
amine as defined above.
Lubrication of substrates herein contemplated can
be accomplished by applying the herein-described composition
wherein the ester lubricants are generally present in a solvent
in an amount less than three weight percent to a given substrate,
i5 evaporating the solvent thererom, and lightly buffing, if
desired~ the thus-coated substrate to pxovide a clear coating.
Application of the compo~ition can be accomplished by numerou~
means including spraying, dipping, brushing, swabbing, flowing
and doctoring. For mos$ purposes, spraying and swabbing are
2~ preferred because of the complete and uniform coverage these
methods afford.
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There can be added to the composition of the
present invention minor amounts of various conventional
components including antioxidants, pigments, hardeners,
illers, binders, odorants, dyes and the li~e if there is
S need to do so and to the extent that such ingredierts are
soluble or dispersible in the solvent and do not degxade
the pexformance characteristic of the present compositions.
The ester lubricants herein contemplated are those
that are solubla in the aforementioned solvents and for the
most part do not exist in the compositions hereindescribed
as particles ox as colloidal suspensions. In effect, the
compositions of the present invention are generally essentially
clear, homogeneous solutions, that is, each exhibits a
uniform composition through its entire volume without any
turbidity.
The ester lubricants herein contemplated and
disclosed may be employed in amounts ranging from about 3.0
to about 0.001 weight percent based on the total weight of the
solution, preferably from about 0.2 to about 0.01 weight percent
and especially from about 0.1 to about 0.03 weight percent.
The resulting treated axticle which also forms a part of this
invention is made by applying the compositions to the surface
and removing the carrier therefrom whereby there is deposited
thereon a coating of the ester ranging from about 0.3 to 3
micrograms per square centimeter.
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- 22 -
Treatrnent of the various substrates herein
contemplated can be accompli~;hed by applying the above-
described compositions in a concentration generally less about
three weight percent, evaporating the solvent therefrom to
provide a coating or film t:hereon which comprises an ester.
In practice a concentration of between about O.l to 0.03 weiqht
pexcent has been found to be satisfactory for treating
phonograph records. Further, it has been found advantageous
; to buff or polish after treatment to impart a good luster to
the playing surface thereof.
- There will be illustrated herein preferred examples
of the lubricating composition of this invention and method
of using the same. The specific illustration~, however, are
not intended to be a limitation upon the breadth of the
invention. Generally, the invention taught herein is one in
which a volatile but effective carrier transports therein an
ester, the composition forming a ~ilm upon a given substrate
after the solvent has volatilized.
EXAMPLE I
A solution was prepared comprising 99.96 percent by
C~ frad~?al~K
B weight of trichlorotrifluoroethane (Freon TF~) and 0.04 percent
by weight of perfluoroalkyl citrate (this triester is available
under the trade mark Zonyl TBC from E.I. du Pont de ~emours
& Co., Wilmington, DE), the average perfluoroalkyl moiety
thereof ranging from heptyl to octyl. A clear homogeneous
Z~
solution resulted and was sprayed onto a clean phonograph
test records, National Association of Broadcaster~ (NAB~
test record No. 12-5-98, the trichlorotrifLuoroethane was
allowed to evaporate, and t:he playing surface was lightly
buf~ed to leave a thin coating of said ester thereon.
A stylus/groove coefficient of friction t08t wa8
conducted~on the phonograph record before and after the
treatment descxibed by measuring the change in the
deceleration rate of the freely rotating phonograph record
on a turntable, the deceleration change being cau~ed by the
engagement of the tone arm stylus with the record groo~e.
This chaage in deceleration is converted to stylus/groove
coefficient of friction by the following formula:
f a I (A -A ) sin 45
t t ~ _
SR
f = coefficient of friction.
I - moment of inertia of total rotating system.
A = angular decelexation for the total effectQ
t
of stylus and turntable bearings.
A c angular deceleration for the effect of the
turntable bearings alone.
S a Stylus force on record.
R - mean record radius at groove where stylus is
sliding.
Using the above formula l:he coefficient of friction
,
- . . . . :
~ ' ' ', " ' - ~
1~ Z~7~3~
- 24 -
before coating with the aforementioned citrate composition
was 0~35 and after application of said composition tha
- coefficient of friction was reduced to 0~180
Another composition was prepared a~ above with the
exception that 0.04 weight percent fluoroalkyl stearate wa~
used in place of the a~orementioned citrate, thiæ monoester
being available from E.I. di Pont de Nemours & Co.,
Wilmington, Delaware, United States America. The avaxage
perfluoroalkyl moiety of said monoester ranged from heptyl
to octyl. The coefficient o~ friction of the untreated
record was 0~33 where the treated record with the fluoroalkyl
stearate gave a coefficient of friction of 0.11.
EXANPLE II
Accelerated phonograph record wear tests were
conducted on NAB test records which had been treated with
the compositions hereinafter disclosed. The results achieved
from cleaned and treated records were compared with the results
of the wear test conducted on a cleaned test record which had
not been treated in accordance with the present invention. A
graduated scale was established ranging from a rating of zero
for a clean, mint condition appearance to a rating of 100 for
a surface heavily covered with wear debris. A test utilized
; a;standard type automatic record turntable rotating at 33-1/3
rpm type with the stylus on the tone arm adjusted to 9.5 grams
load on the record surface. This high stylus load was used in
.
.
o
- 25 -
order to accelerate the wear process and thereby provide
better discrimination among record treatment$. Various
compositions of the present invention were applied to the
record surfaces in accordance with the proçedure described
in Example I. Test results after 125 to 127 playing cycles
are presented in the tabulation below:
Phono Record SurPace
graph Appearance at
Test Test Termin-
Record Composition of Record Treating a~ion and
Iae~tifi- Solution: Trichlorotrifluoro- Relative
cation __ _ ethane Plus the followinq (wt.%
A 0.04 wt.% fluoroalkyl citrate Relatively
(average perfluoroalkyl portion clean surface
7 to 8 carbon atoms) --scattered
~ine wear
particles:
Rating = 15
B 0.04 wt.% fluoroalkyl stearate Quite clean:
(average perfluoroalkyl portion scattered very
7 to 8 carbon atoms) fine particle$:
Rating = 7
C Control Record Heavily
(~ecord cleaned via mild covered with
detergent) various sizes
particles of
wear debris:
Rating = 100
The above examples show that compositions of the
subject invention effectively prevent phonograph record groove
wear, for the a~ove test results indicate that the compostions
herein described significantly reta.rd wear over a laxge number
. of actual playings~
"
.
. .
.
:
.
I
A solution was prepared comprising 99.96% by weight
of trichlorotrifluoroethane (Freon T~) and 0~04/O by weight of
perfluoroalkyl malonate, the perfluoroalkyl moiety average
thereof ranging from heptyl to octyl. A clear, homogeneous
solution resulted and was sprayed onto a clean p~onograph test
record, ~ational Association of Broadcasters (NAB) test re~ord
No. 12-5-98, the trichlorotrifluoroethane was allowed to
evaporate and the playing surface of the record was lightly
bu~fed to leave a thin coating of diester thereon.
The stylus/groove coefficient of friction test.wa~
conducted in accordance with Example I. The stylys/groove
coefficient of friction determined on the treated record was
0.18. In comparison, the coefficient of friction as determined.
on untreated ~AB records averaged about 0.32.
The accelerated record wear test was also conducted
on the treated record in accordance with Example II and
resulted in the record having a very clean surface appearance
indicating very little record wear and gave a relative rating
~0 of 1Ø
EXAM_LE_IV
A solution was prepared comprising of 99.97 percent
~y weight of denatured alcohol (90% ethyl alcohol, 5% methyl
alcohol and 5% water) and 0.03 percent by weight of polyoxy-
othylene glycol monostearate, the molecular weight of the
~ .
',
, ~ ',.
- 27 -
polyoxyethylene gly~ol porticn beir~ about 400. A cle~r
solution resulted and was sprayed onto a phonograph test
record, ~ational Association o~ Broædcasters (NAB), the
alcohol was allowed to evaporate, and the playing surface was
lightly buffed to leave a thin coating of said monoester
thereon. The record was then subjected to playing and
compared with an untreated record to determine changes in any
surface noise. For this purpose,-the signal from the stylus,
tracking at one gram load in the record groove, was fed to an
oscilloscope for display. During the first number of playing~,
the coated record showed significantly less surface noise than
did an uncoated record; and progressively throughout some 120
playings, the level of background or surface noise of the
coated record ultimately reached the noise level that the
- 15 uncoated record showed on its first playing.
A solution was prepared comprising about 99.02 weight
percent of denatured alcohol (90/O ethyl alcohol, 5% methyl
alcohol and ~% water)~ about 0.05 weight percent polyoxy-
ethylene glycol monostearate, and about 0~03 weight percent
alkyldiethanolamine. The molecular weight of the polyoxy-
ethylene glycol portion of the stearate ester was about 400,
and the alkyl portion of the alkyldiethanolamine was C to C
12 14
A clear solution resulted and was sprayad onto a NAB test
~5 record, the alcohol was allowed to evaporate t and the playing
: - :
: . - . :
.
. - ,, ': ',, - . . : ,:
'- :~ . ' " ' :' - ~ ' ' ' '
~ 27i~
- 28 -
surace was lightly buffed. The accelerated record w~ar t~st
as descr~bed in Bxample II was cond~cted on the treated record
and resulted in the record 'naving a very clean surface
indicating very little record wear and gave a relative rating
of 2Ø
EXAMPLE VI
~nother series of accelera~ed phonograph record
wear tests was conducted on NAR test records which had been
treated with the compositions hereinafter disclosed. The
results achieved from cleaned and treated records were compared
with the results ~f the wear test conducted on a cleaned test
record which had not been treated in accordance with the
present invention. A graduated scale was established ranging
from a rating of zero for a clean, mint condition appearance
to a rating of 100 for a surface heavily covered with wear
debxis. A test utilized a standard type automatic record
turntable rotating at 33-1/3 rpm type with the stylus on the
tone ar~ adjusted to 9.5 grams load on the record surface.
This high stylus load was used in order to accelerate the wear
process and thereby provide better discrimination among record
treatme~ts. Various compositions of the present invention
were applied to thq record surfaces in accordance with the
procedure described in Example I. Test re~ults after 125 to
127 playing cycles are presented i31 the tabulation bPlow:
:
~z~
- 29 -
Phono Record Surface
graph Appearance at
~est Composition of Record Treating Test Termin-
Record Solution: Trichlorotrifluoro- ation and Relative
Identi~i- et~ane plus the followin~ (wt~%) Rating
cation _ _
A 1.0% tetrafluoroethylene Quite cle~n: a
telomer concentrate (20% solids) small numher of
Vydax AR, (decanted), plus 0.02% fine wear
polyethylene glycol monolaurate particles:
(mol. wt. of the polyethylene Rat:ing = 3
glycol portion was about 600)
B 0~03% polyethylene glycol mone- Very clean: a
laurate (mol. wt. of poly- few fine wear
ethylene glycol portion was particles:
about 600) Rating = 2
C 0.06% fluoroalkyl stearate Very clean:
(average perfluoroalkyl portion a few fine w~ar
was 7 to 8 carbon atoms) plus particles:
0.04% polyethylene glycol mono- Rating = 3
laurate (mol. wt. of polyethy-
lene glycol portion was about
600).
D Control Record Heavily covered
(Record cleaned via mild with various
detergent). sized particles
of wear debris:
Rating = 100
The above examples show that compositions of the
subject invention effectively prevent phonograph record groov~
wear, since the compositions have been found to significantly
retard wear over a large number of actual playings~
2(
There have been disclosed herein a method of and a
composition for lubricating surfaces, and in particular those
surfaces which are capable of having or have dynamic
presentations thereon. In view of this specification, those
skilled in the art will have man~ r;lodifications which fall
~,
- . - - .
,, . , - ~ ~:
: . . ,' . : : : .' :.
:- . ~
27~
- 30 -
within the true spirit and scope o~ thi~ in~ntion. It is
intended that all such modiications be within the scope of
the appended claims.
