GB1594954A - Lubricants comprising dialkanolamine derivatives - Google Patents

Description

(54) LUBRICANTS COMPRISING DIALKANOLAMINE DERIVATIVES (71) We, BALL BROTHERS RESEARCH CORPORATION, a corporation of the State of Colorado, located at Boulder Industrial Park, Boulder, Colorado U.S.A., do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement : The present invention relates to recording media requiring lubrication to an lubrication composition for application to such media, and, methods of application. Improved, wear-resistant, low friction media result from simply treating said media with the composition of the present invention. A wide variety of media can be treated with the composition of the invention, having recordings thereon or capable of having recordings thereon. Such media include computer recording discs, magnetic recordings, photographic projection film such as moving picture film, slide film, and microfilm as well as sound and video recordings such as gramophone or phonographic records, and video discs. The invention relates to those recording media for which lubrication would provide an advantage in use.

Sound recording media have been extensively used for some years in at least three major fields, namely, in the manufacture of phonograph records, in recording media in dictating machines wherein they may be in the form of endless belts, sheets; discs and in other forms, and in the computer system field to record data in various plastics coated surfaces in the form of drums and discs.

Lubrication of the various media, and, particularly media upon which recorded signals have been stored and from which said signals can be recalled by dynamic means, has not been generally recognized as a straight-forward act. Where attempts have been made to lubricate such substrates, they have not proven fully satisfactory. In particular, substrates possessing this special problem include synthetic, natural and combinations of thermoplastic materials and includes resins, shellac, polyvinyl acetate, polyvinyl chloride, cellulose acetate, cellulose nitrate, polyvinyl-benzene, and their derivatives. Numerous other compositions are contemplated and especially those which are generally formed through various press moulding means into phonographic records or discs as well as similar thermoplastic structures having trackable, helical groove contours thereon, which when used in conjunction with certain dynamic means such as styli which are capable of following said contours, reproduce recordedmnonoaural and stereophonic and video signals.

As is generally known, a phonograph cartridge serves to convert the variations on the walls of the grooves of a phonograph record into electrical signals whereby the variations or wavy pattern on the grooves determine the frequency and the amplitude of the sound vibrations. The cartridge includes a stylus or pickup needle, usually made of a diamond or sapphire, which generally has a hemispherical 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 atached to an armature which moves with the stylus to induce variations in an electrical or magnetic field in response to 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 comprises the recorded signal.

A stylus has to track a plurality of evenly spaced groove contours with recorded signals of 15Hz to 20,000 Hz. Moreover, with the introduction of discrete four-channel record systems 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 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 results in records becoming unusable and often being discarded within a short period of time. A number of factors are 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 consequent loss of playback fidelity cannot be entirely eliminated. At any rate, most attempts of the prior art via record cleaners or alleged lubricants have simply resulted in cleaning only or depositing chemical films onto records without being successful, in that such materials generally reduce the record fidelity due to rapid groove wear, if cleaned, or to hydrodynamic damping of the stylus tracking, if oil 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 to use powdered solid lubricants such as graphite, molybdenum disulfide and the like have several disadvantages for they do not only reduce the fidelity, but they also increase noise due to particulate interference in the record grooves.

The present invention is founded on the remarkable discovery that the certain dialkanolamines are extremely effective lubricants upon sundry recording media but especially upon those substrates having dynamic presentations thereon, such as phonograph records.

The term "recording medium" as used herein signifies various materials in a form appropriate for the carrying of information said information being recovered by relative movement of the medium to a transcribing element which movement is facilitated by a lubricant on the surface of the medium. The media can be manufactured from plastics metals, or a combination of plastics and metals. In particular the media can be playing elements of synthetic, natural and combinations of thermoplastic materials and include resins, shellac, polyvinyl esters such as polyvinyl acetate, polyvinyl-benzene, polyvinyl chloride, cellulose acetate, cellulose butyrate, cellulose nitrate, their derivatives as well as copolymers and blends thereof. In particular, the term "media" include those elements having 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 reproducing recorded monaural and stereophonic and video signals therefrom.

According to the invention there is provided a recording medium (as defined 'herein) requiring lubrication in use which bears on a surface thereof a lubricating amount of a non-volatile (as defined herein) N-alkyl-substituted N,N-dialkanolamine.

There is also provided a composition consisting essentially of a solution of a non-volatile (as defined herein) N-alkyl-substituted N,N-dialkanolamine in amount of 1.0 to 0.001 weight percent and a volatile (as defined herein) carrier which is an alcohol, ketone, ester, halogenated hydrocarbon or hydrocarbon.

In addition there is provided a method of providing a recording medium with a lubricant on a surface thereof which comprises applying to said surface a composition containing 1.0 to 0.001 weight percent non-volatile (as defined herein) N-alkyl-substituted N,Ndialkanolamine the balance of the composition being a volatile (as defined herein) carrier and evaporating the carrier therefrom.

By non-volatile is meant that the dialkanolamine will not volatilise under normal ambient conditions. Conversely, volatile in relation to the carrier means the carrier will be volatizable under normal ambient conditions. The composition can be easily applied to any number of the aforementioned media and especially to thermoplastic substrates, generally used in the record or gramophone trade upon which are recorded signals in the form of undulations or grooves, the composition herein providing a coating or film that promotes a marked increase in lubrication and reduction in wear properties thereof.

The composition of the present invention which imparts to a given medium allow coefficient of friction consists essentially of a solution of a dialkanolamine in a carrier or solvent therefor. The dialkanolamine preferably has the formula: (HORl)2N-R2 wherein R1 is an alkylene having 2 to 3 carbon atoms, i.e. ethylene, isopropylene and propylene and R2 is an alkyl radical having four to twenty carbon atoms. Illustrative examples of such dialkanolamines are the following: N-butyl-N,N-beta beta '-diethanolamine N-butyl-N ,N-beta ,beta ' -diisopropanolamine N-octyl-N,N-beta,beta'-diethanolamine N-octyl-N ,N-beta ,beta' -diisopropanolamine N-octyl-N,N-gamma, gamma' -diisopropanolamine N-decyl-N,N-beta,beta'-diethanolamine N-decyl-N,N-beta,beta'-diisopropanolamine N-decyl-N ,N-gamma gamma' -diisopropanolamine N-lauryl-N,N-beta,beta'-diethanolamine N-lauryl-N ,N-beta ,beta ' -diisopropanolamine N-lauryl-N ,N-gamma ,gamma' -dipropanolamine N-myristyl-N,N-beta,beta'-diethanolamine N-myristyl-N ,N-beta ,beta' -diisopropanolamine N-myristyl-N ,N-gamma ,gamma' -dipropanolamine N-butylauryl-N ,N-beta beta' -diethanolamine N-butylauryl-N ,N-beta ,beta'-diisopropanolamine N-butylauryl-N,N-gamma,gamma' -dipropanolamine N-stearyl-N,N-beta,beta'-diethanolamine N-stearyl-N ,N-beta ,beta ' -diisopropanolamine N-stearyl-N ,N-gamma,gamma ' -dipropanolamine.

The dialkanolamines can be readily made by conventional chemical techniques known in the art. A process for preparing various N-alkyl-substituted N,N-beta,beta!- dialkanolamines is generally known in the art wherein N,N-beta,beta'-diethanolamines or N,N-beta,beta'-diisopropanolamines are reacted with certain higher molecular alkyl halides in the presence of specified added organics having the property of acting as a mutual solvent for the reactants but providing relatively high yields of the N-alkyl-substituted N,N-dialkanolamines.

The dialkanolamines herein contemplated and disclosed may be employed in amounts ranging from 1.0 to 0.001 weight percent based on the total weight of the mixture, preferably from 0.05 to 0.01 weight and especially from 0.03 to 0.01 weight percent. The resulting treated article which also forms a part of this invention is made by applying such to the surface and removing the carrier whereby there is deposited thereon said dialkanolamines ranging from 0.3 to 3 micrograms per square centimeter.

The preferred dialkanolamines are the following: (HOCH2CH2 2NC12H25 HOCH2CH2 2NC13H27 (HOCH2CH2 2NC14H29 In general these dialkanolamines have a density of about 0.89 g/ml at ca. 75" F.

The preferred carrier of said composition is trichlorotrifluoroethane; however, any of a number of other volatile solvents is a useful carrier for dialkanolamines, provided only that it has no adverse effect on the substrates and has adequate dissolution powers for dialkanolamines. The trichlorotrifluoroethane, which can be either 1,1,1-trichloro-2,2,2trifluoroethane or 1,1,2-trichloro-1,2,2-trifluoroethane, is a particularly desirable carrier for application of dialkanolamines to plastics substrates because of its compatibility with most plastics materials, including those used to manufacture phonograph records, video discs, and other recording media.

The other aforementioned useful carriers may be incorporated in the composition of the present invention either individually or in misdible combinations with one another or with trichlorotrifluoroethane, provided there is no adverse effect upon the substrate. Such other carriers include the following: Alcohols Ketones Esters Methanol acetone ethyl acetate Ethanol methyl ethyl ketone propyl acetate n-propanol methyl propyl ketone isopropyl acetate isopropanol methyl isopropyl ketone butyl acetate methyl isobutyl ketone diethyl ketone ethyl propyl ketone ethyl isopropyl ketone Halogenated Hydrocarbons Hydrocarbons carbon tetrachloride benzene chloroform toluene methylene chloride xylene methyl-chloroform pentane tetrachloroethylene hexane trichloroethylene heptane dichloroethane octane dichloroethylene perfluorodimethylcyclobutane benzotrifluoride Treatment of the various media herein contemplated can be accomplished by applying the above-described composition in a concentration generally less than one weight percent of the dialkanolamine relative to the volatile carrier on the medium, evaporating the carrier therefrom to provide a coating or film thereon which consists essentially of the non-volatile portion of the composition, i.e. the said dialkanolamine. Application of the composition can be accomplished by numerous means including spraying, dipping, brushing, swabbing, flowing and doctoring. For most purposes, spraying and swabbing are preferred because of the complete and uniform coverage these methods afford.

There will be illustrated herein preferred examples of the lubricating compositions of this invention and method of using the same. The specific illustrations, however, are not intended to be a limitation upon the breadth of applicant's invention. Generically, the method of the invention taught herein is one in which a volatile carrier transports therein an essentially non-volatile material, the latter forming a film upon a given medium after, the carrier has volatilized.

Example I A solution was prepared consisting of 99.97 percent by weight of trichlorotrifluoroethane (Freon (Registered Trade Mark) TF) and 0.03 percent by weight of Anti-Stat 273C, a commercial N,N-bis(2-hydroxyethyl)alkylamine (available from Fine Organics, Incorporated, Lodi, New Jersey), the alkyl moiety thereof ranging from dodecyl to tetradecyl. A clear solution resulted and was sprayed onto a phonograph test record, National Association of Broadcasters (NAB) test record No. 12-5-98, the trichlorotrifluoroethane was allowed to evaporate, and the playing surface was lightly buffed to leave a thin coating of said alkylamine 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 grooves, was fed to a Tektronix (Registered Trade Mark) 5100 Series Storage Oscilloscope for display. During the first number of playings, 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 uncoated record showed on its first playing.

Example 11 Accelerated phonograph record wear tests were conducted on NAB test records which had been treated with the compositions of the subject invention. The results achieved from 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. The test utilized a standard type automatic record turntable rotating at 33-1/3 rum with the stylus on the tone arm 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 treatments. Various compositions of the present invention were applied to the record surfaces in accordance with the procedure described in Example I. Test results are presented in the tabulation below: Phono- Record.Sur- graph Composition of face appear Test Number Record Treating ance at Test Record of Solution: Trichloro- Termination Identifi- Times triftuornethane plus and Relative cation Played the following (wt. %) 'Rating (0 = clean, 100 = heavily covered with wear debris) A 129 0.03% by wt. N.N-bis Clean surface (2-hydroxyethyl)alkyl- no visible amine, (alkyl = wear particles C12-C14, Anti-Stat Rating = 0 273C.

B 108 0.018% by wt. N,N-bis Practically (2-hydroxyethyl)alkyla- clean--1 or 2 mine, (alkyl = Cl2-Cl4), visible wear Anti-Stat 273C. particles.

Rating = 1 C 130 0.03% by wt. N,N-bis Practically (2-hydroxyethyl)alkyla- clean--a few mine, (alkyl = C18), wear particles.

Anti-Stat 273E. Rating = 2 D 128 None; control record. Surface evenly Record surface was flecked with wiped with velvet visible but swatch saturated with tiny white trichlorotrifluoro- wear debris.

ethane only. Rating = 75 The above examples show that compositions of the subject invention effectively prevent phonograph record groove wear and preserve original recorded fidelity; and the compositions markedly reduce background or surface noise when applied to a record and significantly retard the rate of noise increase rover a large number of actual playings.

WHAT WE CLAIM IS: 1. A recording medium (as defined herein) requiring lubrication in use which bears on a surface thereof a lubricating amount of non-volatile (as defined herein) N-alkyl-substituted N ,N-dialkanolamine.

2. A recording medium according to claim 1 carrying a signal recallable by dynamic means.

3. A medium according to claim 2 in which the medium is a disc having a trackable helical groove.

4. A medium according to any one of claims 1 to 3 wherein the recording medium has a surface of a moldable plastics material which-is cellulose acetate, cellulose nitrate, shellac, polyvinyl chloride', polyvinyl acetate, polyvinylb nzene or a blend or copolymer of said polyvinyl compounds with one another.

5. A medium according to claim 1 which is a magnetic recording element.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (15)

1. **WARNING** start of CLMS field may overlap end of DESC **.

   record which had not been treated in accordance with the present invention. The test utilized a standard type automatic record turntable rotating at 33-1/3 rum with the stylus on the tone arm 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 treatments. Various compositions of the present invention were applied to the record surfaces in accordance with the procedure described in Example I. Test results are presented in the tabulation below: Phono- Record.Sur- graph Composition of face appear Test Number Record Treating ance at Test Record of Solution: Trichloro- Termination Identifi- Times triftuornethane plus and Relative cation Played the following (wt. %) 'Rating (0 = clean,

   100 = heavily covered with wear debris) A 129 0.03% by wt. N.N-bis Clean surface (2-hydroxyethyl)alkyl- no visible amine, (alkyl = wear particles C12-C14, Anti-Stat Rating = 0 273C.

   B 108 0.018% by wt. N,N-bis Practically (2-hydroxyethyl)alkyla- clean--1 or 2 mine, (alkyl = Cl2-Cl4), visible wear Anti-Stat 273C. particles.

   Rating = 1 C 130 0.03% by wt. N,N-bis Practically (2-hydroxyethyl)alkyla- clean--a few mine, (alkyl = C18), wear particles.

   Anti-Stat 273E. Rating = 2 D 128 None; control record. Surface evenly Record surface was flecked with wiped with velvet visible but swatch saturated with tiny white trichlorotrifluoro- wear debris.

   ethane only. Rating = 75 The above examples show that compositions of the subject invention effectively prevent phonograph record groove wear and preserve original recorded fidelity; and the compositions markedly reduce background or surface noise when applied to a record and significantly retard the rate of noise increase rover a large number of actual playings.

   WHAT WE CLAIM IS: 1. A recording medium (as defined herein) requiring lubrication in use which bears on a surface thereof a lubricating amount of non-volatile (as defined herein) N-alkyl-substituted N ,N-dialkanolamine.
2. 2. A recording medium according to claim 1 carrying a signal recallable by dynamic means.
3. 3. A medium according to claim 2 in which the medium is a disc having a trackable helical groove.
4. 4. A medium according to any one of claims 1 to 3 wherein the recording medium has a surface of a moldable plastics material which-is cellulose acetate, cellulose nitrate, shellac, polyvinyl chloride', polyvinyl acetate, polyvinylbènzene or a blend or copolymer of said polyvinyl compounds with one another.
5. 5. A medium according to claim 1 which is a magnetic recording element.
6. 6. A medium according to any one of claims 1 to 5 wherein the N-alkyl-substituted

   M,N-dialkanolamine has the formula (HOR1) 2N-R2 wherein R1 is an alkylene which is ethylene, isopropylene or propylene and R2 is an alkyl radical having four to twenty carbon atoms.
7. 7. A recording medium as claimed in claim 1 substantially as hereinbefore described.
8. 8. A composition consisting of a solution of a non-volatile (as herein defined) N-alkyl-substituted N,N-dialkanolamine in amount of 1.0 to 0.001 weight percent in a volatile carrier (as herein defined) which is an alcohol, ketone, ester, halogenated hydrocarbon or hydrocarbon.
9. 9. A composition according to claim 8 wherein said dialkanolamine has the general formula (HOR1) 2N-R2 wherein R1 is alkylene having two td three carbon atoms and R2 is an alkyl radical having 4 to 20 carbon atoms.
10. 10. A composition according to claim 8 or 9 wherein the halogenated hydrocarbon has one to six carbon atoms.
11. 11. A composition according to claim 10 wherein the halogenated hydrocarbon is trichlorotrifluoroethane, perfluorodimethylcyclobutane, carbon tetrachloride, chloroform, methylene chloride methyl-chloroform, tetrachloroethylene, trichloroethylene, dichloroethane or dichloroethylene.
12. 12. A composition according to claim 8 substantially as hereinbefore described;
13. 13. A method of providing a recording medium with a lubricant on a surface thereof which comprises applying to said surface a composition containing 1.0 to 0.001 weight percent non-volatile (as defined herein) N-alkyl-substituted N ,N-dialkanolamine the balance of the composition being a volatile (as defined herein) carrier and evaporating the carrier therefrom.
14. 14. A method according to claim 13 wherein the N-alkyl-substituted N,Ndialkanolamine has the formula (HOR1) 2N-R2 wherein R1 is alkylene of two or three carbon atoms and R2 is an alkyl radical of four to twenty carbon atoms,' the volatile carrier is at least one of alcohols, ketones, esters, halogenated hydrocarbons and hydrocarbons and the amount of composition applied and the concentration of, the composition provides when evaporated a coating of 0.3 to 3 micrograms of the N-alkyl-substituted N,N-dialkanolamine per square centimeter of the surface to which the composition is applied.
15. 15. A method according to claim 13 for applying a lubricant to the surface of -a recording medium substantially as hereinbefore described.