DE2624350A1 - LUBRICANTS AND LUBRICATION PROCEDURES - Google Patents

Description

KRAUS & WEISERT

DR. WALTER KRAUS DIPLOMA CHEMIST. DR.-ING. ANN EKÄTE WEISERT DIPL-ING. SPECIALIZATION CHEMISTRY D - 8 MUNICH 19 FLÜGGENSTRASSE 17 TELEPHONE 089/177061. TELEX O5-215145 ZEUS

TELEGRAM CRAUS PATENT

1244 AW / MY

BALL BROTHERS RESEARCH CORPORATION Boulder, CoI. / UNITED STATES

Lubricants and methods of lubrication

The invention relates generally to the lubrication of substrates. In particular, it relates to an improved one Two component lubricant and a method for its use. The invention also relates to scratch-resistant, lubricated low friction substrates such as photographic films, sound recording and reproducing elements and similar materials.

The lubrication of various substrates and particularly substrates on which information is stored and from which the information can be obtained by dynamic means has long been known to be difficult. Examples of such substrates are recording disks for computers, records for turntables, magnetic recording materials for sound and video production and photographic "films such as cinema films, Slide films and microfilms. Previous attempts for a

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Lubrication just had varying degrees of success.

For example, the lubrication of a photographic film, and particularly the lubrication of a photographic film Film that is used either statically or dynamically for the projection of images by using a beam of light passes through the transparent photographic film, one of the most difficult lubrication problems. Becomes a photographic When film is repeatedly placed in a film projection window or holder, the mechanical parting surface rubs watch the film. In motion pictures, such abrasion or sticking will result in a misrepresentation on the Screen when the movie is held and released. Recently there has been another area of application in which the requirements are even bigger. This occurs with cartridges for continuous roll film, where there is a continuous loop photographic film that unwinds inside the roll and recovers on the periphery of the roll winds up. Quite a considerable amount of friction occurs when the photographic film is in a general direction sideways Spiral type is pulled out from the inner part of the roll. Despite the greatly increased possibility of wear and tear, the Cartridges with continuous loop films are increasingly used, for example for projection of entertainment films in airplanes, sales films, educational films, etc.

Photographic films are difficult to smear and wear due to their nature Substrates. Basically, there is a photographic film from a relatively soft emulsion coated on a generally flexible support. The emulsion must be protected against abrasion and have a low coefficient of friction. A low coefficient of friction alone is not sufficient for the necessary protection, - since the soft emulsion does not have the strength that it

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withstand essential forces acting on them, even when the friction is low. In the past, however, attempts have mainly been made to increase the coefficient of friction and therefore often no protective coating is provided for sufficient surface strength. Because the emulsion If the inherent strength and abrasion resistance are poor, the lubricating coating must have these properties in addition result in low friction. In addition to the emulsion side, it is also important that the "backside" of the film is protected and lubricated, as cracks in it become visible when projected.

It is also important that the lubricant coating for photographic films, and particularly for photographic films intended for projection, be transparent. With many known coatings, the only way to avoid turbidity is that they are applied as very thin coatings. In order to achieve suitable, if not complete, light transmission, the essentially cloudy lubricants are only applied in small amounts. The difficulty of haze is exacerbated when properties, such as strength, other than lubricity are created by using more than one component.

Although photographic film is particularly difficult to lubricate, it is also magnetic to lubricate Recording and reproducing elements complicated when also different. The coatings from the lubricants must be very thin so that the interaction between the recording or pick-up head and the magnetic particles is not is disturbed. The lubricant coating must not collect on the head. In the case of disc and cylindrical Rotor recording elements cause the "sliding Heads "or" magnetic heads "used in such recording elements

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elements are used on the element "background noise", and strongly localized forces are formed · The disk must be protected in such a way that damage that occurs as a result of such "interference noises" or "clicks" is avoided. A magnetic tape consists of highly abrasion-resistant particles, which are dispersed in a binder. Without protection, the recording head can quickly be worn out by the particles when the magnetic tape moves over the recording head. In short, must, conditioned by the operating environment and the type of magnetic recording elements in which these lubricants are used, who meet high requirements.

In addition to photographic film lubrication, there are phonographical ones Record elements of importance. For example With phonographic records, the more often they are played, the sound quality deteriorates. For that are responsible for various factors such as general wear and tear from abrasion and adhesive wear mechanisms to an extent proportional to the loading of the needle. That burden isn't just dead weight the needle load, but also includes dynamic inertia forces caused by the needle mass and frequency the changes in direction of the needle are caused when it follows the groove deflections. It is known that by a decrease in dead weight load and needle mass decreases the rate of groove wear; but the wear and tear and the corresponding loss of playback quality for the second leg cannot be completely eliminated. In the past it was mostly lubricated by using fluids or wax-like lubricant deposits on the records. This has the disadvantage that these materials improve the reproduction quality of the record due to hydrodynamic damping of the needle track. When using these materials it is often observed that the noise level is increased. This is mainly due to dust caught by the

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sticky film is held in place. Powdered, solid Lubricants such as graphite, molybdenum disulfide and similar materials decrease the fidelity and generate noise caused by the fine particles disturb in the grooves.

Various waxes and other compounds have been used to lubricate substrates. One also has fluorinated agents have been used as lubricants in various applications, for example fluorinated polymers have been used used in the lubrication of magnetic tapes.

For photographic films you have Vydax AR, a commercially available tetrafluoroethylene telomer as a photographic Film lubricant used. This specific lubricant is used as a comparative sample when testing the Effectiveness of the method and means according to the invention used.

It is an object of the present invention to provide lubricants and lubricating methods which can be used in lubricating various substrates including photographic materials and which Do not have disadvantages of the known means and methods.

The invention is a lubricant, which is characterized in that it is a mixture of one Copolymer of trifluorochloroethylene and vinylidene fluoride, a tetrafluoroethylene telomer and a solvent for contains the copolymer and the telomer.

The invention relates to a method for lubricating substrates, which is characterized in that one is a mixture which is a copolymer of trifluorochloroethylene and vinylidene fluoride, a tetrafluoroethylene telomer and contains a solvent, produces the mixture

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the substrate applies and the solvent with the deposition of a lubricant coating on the substrate from the Mixture removed.

According to the invention, an abrasion-resistant or wear-resistant, smooth, slippery coating for substrates using a two component composition created. One component primarily provides the lubricity, the other primarily provides the coating the strength. Both components together show a synergistic effect and result in a coefficient of friction, which is lower than what is obtained by each component separately. Optionally, the composition can easily refined to produce a transparent coating for photographic films, the preferred lubricating properties are retained.

. According to the invention, a mixture which is a copolymer with a relatively short chain length or a mixture of copolymers for creating a hard, wear-resistant surface and a tetrafluoroethylene telomer with contains relatively short chain length for slipperiness, making for a very good, wear-resistant and optionally translucent coating, the one has low friction, used on a substrate. In the present invention, copolymers can be used as copolymers used by trifluorochloroethylene and vinylidene fluoride will. Copolymers of trifluorochloroethylene and vinylidene fluoride do not act as lubricants. If such copolymers are used alone, for example in photographic films, they give coefficients of friction which are above 0.3. The telomer of tetrafluoroethylene does not act as a lubricant. Will it be alone, for example to a photographic film is applied the coefficient of friction about 0.11. If the two substances

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zen applied together on a photographic film, i.e. a mixture of telomer and copolymer is used, this gives a coefficient of friction of 0.08. If the telomere is used alone on a standard vinyl record, thus it has a coefficient of friction on the order of about 0.14 and the copolymer about 0.23. Will when both are used together, the coefficient of friction is greatly reduced to about 0.07. This remarkable decrease of the coefficient of friction relative to the coefficient of the individual lubricants in the composition an additional effect to the main function of the copolymers, i.e. the achievement of a solid or resistant, abrasion-resistant surface. It was surprising to find this latter effect with an acceptable coefficient of friction could be achieved, and it was particularly surprising that the overall coefficient of friction improved so much could be.

It has been found that the clarity of the agents according to the invention, the copolymers of trifluorochloroethylene and vinylidene fluoride, telomers, and a solvent is surprisingly good. If there is noticeable cloudiness, separation can easily be carried out by conventional decanting, filtering or centrifuging.

Various solvents can be used provided that they have no adverse effect on the Own substrate. Trichlorotrifluoroethane is particularly preferred as it has the appropriate organic dissolution properties and has a high volatility and also hardly any physical or chemical influences on the substrate shows. The trichlorotrifluoroethane can be any isomer, i.e. it can be 1,1,1-trichlorotrifluoroethane or 1,1,2-trichlorotrifluoroethane be. Other solvents that can be used are benzotrifluoride and perfluorodimethyl cyclobutane. To the solvents described above

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can certain halogenated aliphatic hydrocarbons are added such as 1,1,1-trichloroethane, chloroform, Tetrachlorethylene, trichlorethylene, methylene chloride, Carbon tetrachloride, dichloroethylene, dichloroethane and / or Mixtures of these.

In the copolymer, the ratio of trifluorochloroethylene to vinylidene fluoride is preferably about 80:20, where the copolymerization reaction is terminated at a time when the average molecular weight is low is enough that the material is at a concentration of at least up to about 10% by weight in trichlorotrifluoroethane is soluble. This copolymer has a specific gravity of about 2.02 and is available under the trademark "KeI F 800 "available from 3M Company, St. Paul, Minnesota.

A suitable tetrafluoroethylene telomer has a specific gravity of about 2.16 and a melting point of 300 ⁰ C. It is a 20% solids suspension in trichlorotrifluoroethane of EI DuPont de Nemours and Company, Wilmington, Delaware, under the trademark "Vydax AR" available as . Another tetrafluoroethylene telomer that is commercially available is supplied by Pennwalt Chemical Corporation of 3 Penn Center, Philadelphia, Pennsylvania under the trademark "MP-51". Generally, this telomer is a fully halogenated telomer, that is, it has zero hydrogen content and a molecular weight in the range of about 700 to about 1,800.

The particularly described copolymers can be readily mixed with a number of other suitable copolymers, including the copolymers of trifluorochloroethylene and vinyl chloride are mixed. Average molecular weights below about 100,000 for the trifluorochloroethylene and vinyl chloride copolymer are in the preferred range for such co-

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polymers added to the lubricants according to the invention will. However, the actual molecular weights are not critical as the higher molecular weight fractions can easily be separated according to a preferred embodiment of the invention.

The concentrations of poly (trifluorochloroethylene-co-vinylidene fluoride) copolymers and tetrafluoroethylene telomers in the solvent can be within wide ranges vary. In general, a preferred mixture is prepared by adding the poly (trifluorochloroethylene-co-vinylidene fluoride) to the solvent at a concentration of at least about 0.005% by weight and the tetrafluoroethylene telomer is added in a concentration of at least about 0.01% by weight. The separation stage described above can, if necessary, can be carried out easily even when the copolymer and telomer are in a highly diluted state, what is indicated by low concentrations.

The agents or compositions (these terms are used synonymously in the present application) can Contain any suitable additives according to the specific end use. For example, coatings for photographic films, records for turntables, etc. to avoid the formation of electrical Charge on the substrate during use contain common antistatic agents. These funds should of course be compatible with the lubricant in terms of solubility, reactivity, etc. However, it is not difficult select suitable additives.

Lubrication of the substrates can be accomplished by using the above-described dilute solutions of lubricating compositions on such substrates, evaporation of the solvent and, if necessary, light polishing of the so coated Substrate to produce a clear coating.

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The funds can be used in a number of ways. You can spray the remedies on, you can immerse yourself, you can brush it up, you can let it flow or with it Apply or brush on doctor blades. All of these procedures are possible. For most purposes it is a spray on and immersion are preferred as these methods give complete and complete coverage. Alternatively, you can Apply poly-ctrifluorochloroethylene-co-vinylidenfluoril) first and then a coating of the telomere thereon attach. This gives results that are comparable to those are obtained when the ingredients are applied in a mixed state.

The following examples illustrate the invention.

example 1

Lubricants according to the invention are prepared by adding the amounts of copolymer given in Table I. to solutions of the telomere there. For agents that are decanted off, the solution is made by mixing the mixture from solvent plus ingredients to equilibrium and then the dissolved parts of the ingredients and decanting the solvent from the undissolved solids. An acetate-based color film for cinema is then machined by dipping it in the indicated solutions of lubricants and excess Solution removed. The film is then dried and slightly polished. The resulting, lubricated film will then the pin and disk wear test subjected to a laboratory test which showed a significant correlation with the wear resistance of the film in actual use.

The needle-and-washer test is performed by a short length of film is placed on the surface of a disc

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V *.

solidifies and rotates at a speed of 30 rpm with a load of 410 g, the load with a stationary 1.25 cm (1/2 inch) steel sleeve sliding on the film. The films will tested, Ms they fail, which is due to visible cracks in the emulsion and / or an increase in the friction between the slider and the movie.

Table I.

Sample lubricant composition trichlorotrifluoroethane plus the following compounds (Wt.%)

Needle-and-washer test, average usage time, cycles

0.25% tetrafluoroethylene telomer, MP-51 0.25% tetrafluoroethylene telomer, MP-51 plus 0.02% poly (trifluorochloroethylene-co-vinylidene fluoride), "KeI F 800" 0.25% tetrafluoroethylene telomer, MP-51 plus 0.05% poly (trifluorochloroethylene-co-vinylidene fluoride), "KeI F 800) 0.25% tetrafluoroethylene telomer, MP-51 plus 0.5% poly (trifluorochloroethylene-co-vinyl chloride), FPC 461 (decanted) 1.0% tetrafluoroethylene telomer, MP-51 1% tetrafluoroethylene telomer, MP-51 plus 0.5% poly (trifluorochloroethylene-co-vinyl chloride), FPC 461 (decanted)

no treatment

390 802

1882 454

997 1652

154

From the values in Table I it can be seen that a combination of the specified copolymer and telomers gives an agent that gives a longer film life compared to the tetrafluoroethylene telomer itself. It is shown that by adding 0.02% poly (trifluorochloroethylene-co-vinylidene fluoride) 0.25% tetrafluoroethylene telomer, the average service life is increased from 390 to 802 cycles (sample A and sample B). By adding of 0.05% poly (trifluorochloroethylene-co-vinylidene fluoride) will she

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increased significantly to 1882 cycles (sample A and sample C). By adding 0.5% poly (trifluorochloroethylene-co-vinyl chloride) to 0.25% tetrafluoroethylene telomer (sample A and
Sample D) results in an average increase in the service life limit from 390 to 454 cycles. If 0.5% poly (trifluorochloroethylene-co-vinyl chloride) to 1% tetrafluoroethylene telomer (sample E and sample F) is added, the service life is increased from 997 to 1652 cycles.

Example 2

The influence of the copolymer component on the frictional properties of the lubricant is used in both films for cinema as well as record recording material substrates certainly. The results are shown in Table II.

Table II

Substrate lubricant trichlorotrifluoroethane friction plus the following compounds (wt.%) Coefficient

Film emulsion film-on-film test

A 0.1% tetrafluoroethylene telomer, MP-51 0.11-0.13

B 0.1% tetrafluoroethylene telomer, MP-51 plus 0.08-0.11 0.5% poly (trifluorochloroethylene-co-vinyl chloride) , FPC 461 (decanted)

Paper clip test

C 1.0% tetrafluoroethylene telomer, Vydax AR 0.11 (decanted)

D 1% tetrafluoroethylene telomer, Vydax AR, plus 0.08 0.04% poly (trifluorochloroethylene-Co-vinylidene fluoride), KeI F 800 (decanted)

E 0.28% poly (trifluorochloroethylene-Co-vinyl-0.03 lidenefluoride), KeI F 800

Vinyl paper clip record test

F 0.2% tetrafluoroethylene telomer, MP-51 0.14

G 0.125% tetrafluoroethylene telomer, MP-51 plus 0.07 0.075% poly (trifluorochloroethylene-co-vinylidene fluoride), KeI F 800

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Table II (continued)

Substrate lubricant trichlorotrifluoroethane friction plus the following compounds (wt.%) Coefficient

Vinyl paper clip record test

H 0.28% poly-trifluorochloroethylene Corvi- 0.23 nylidenfluorid), KeI F 800

I 0.50% poly-trifluorochloroethylene-co-vinyl 0.18 Chloride), FPC 461 (decanted)

The values in Table II show that the combinations of the specified copolymers and tetrafluoroethylene telomers Provide compositions which provide substrates which generally have lower coefficients of friction than one it is observed when tetrafluoroethylene telomers are used alone. Are 0.5% poly (trifluorochloroethylene-covinyl chloride) 0.1% tetrafluoroethylene telomer (sample A and sample B, table II) and is decanted off as indicated, the film-on-film friction of the films treated with these solutions increases from 0.11 to 0.13 in the case of the tetrafluoroethylene telomer solution from 0.08 to 0.11 in the mix.

In the film-on-film rub test, a length of the film to be tested is applied to the cylindrical outer surface attached to a disc with a horizontally mounted axis. Another length of film is pinned over the first Film length laid with the emulsion side of the attached Film touches the back of the second length. A calibrated weight is placed on one end of the second length of film and a force is applied to the other end until there is movement between the two lengths of film. By common calculations, the coefficient of friction between the film lengths is determined for the various films calculated.

The following methods are used as the paper-clip friction method: "Processed Film Lubrication:

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Measurement by Paper Clip Friction Test and Improvement of Projection Life "by T. Anvelt, J.F. Carroll and L.J.Snyder, Journal of the Society of Motion Picture and Television Engineers, Volume 80, Pages 734-739 (1971). One poses solid, which can be seen from Table II that the coefficient of friction decreases from 0.11 to 0.08 (sample C and sample D), when 0.04% poly (trifluorochloroethylene-co-vinylidene fluoride) is added to 1% tetrafluoroethylene telomer. Any solution is first decanted from insoluble tetrafluoroethylene telomer residue. (A mixture of 1% tetrafluoroethylene telomer, Vydax AR, in trichlorofluoroethane after settling and decanting a solution that contains about 0.04% dissolved tetrafluoroethylene telomer.) Poly (trifluorochloroethylene-co-vinylidene fluoride) is not a lubricant per se, which is due to the high coefficient of friction (greater than 0.3), which is obtained from a film made with a solution of 0.28% poly (trifluorochloroethylene-co-vinylidene fluoride) is treated in trichlorotrifluoroethane (Sample E, Table II).

Table II also shows the friction values obtained from standard vinyl record samples obtained with solutions of poly (trifluorochloroethylene-co-vinylidene fluoride), tetrafluoroethylene telomer and their mixtures were treated in trichlorotrifluoroethane as a solvent. You notice that a 0.2% tetrafluoroethylene telomer solution itself gives a coefficient of friction of 0.14 (sample F), a mixture from 0.125% tetrafluoroethylene telomer and 0.075% poly (trifluorochloroethylene-co-vinylidene fluoride) gives one of 0.07 (Sample G). A solution of the latter (0.28% gives itself one of 0.23 (Sample H).

Example 3

Lubricants are used to demonstrate the effect on the friction of recording material

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Mixtures of tetrafluoroethylene telomer plus poly (trifluorochloroethylene-co-vinyl chloride) on the one hand with mixtures of the same telomer plus poly (trifluorochloroethylene-covinylidene fluoride) on the other hand, see Table III,

Table III

Recording recording material treatment Paper clips, vinyl Solution composition: trichloride friction

trifluoroethane solvent plus test, Λ% tetrafluoroethylene telomer friction coefficient (Vydax AR) plus the following compound fertilize

Poly- (trifluor- poly- (trifluor-

chlorethylene chlorethylene

Co-vinyl chloride co-vinylidene

FPC 461 (abde- fluorid) Kel F

edged) 800 (decanted)

Wt% wt%

A - 0.04 0.09

B 0.083 0.033 0.10

C 0.167 0.027 0.09

D 0.25 0.02 0.10

E 0.42 0.0067 0.08

F 0.50-0.08

G- - 0.14

From the values in Table III it is readily apparent that uniformly favorable results are obtained when one the two copolymers mixed with the telomer, regardless of the relative concentrations, as indicated by a comparison of samples A to F with the telomere solution itself (sample G) emerges.

The various specific embodiments of the present invention have been made on particularly difficult substrates explained. It will be recognized, however, that numerous changes and modifications can be made that other substrates can be used.

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Claims (21)

Claims 1. Lubricant, characterized in that it contains: a mixture of a copolymer of trifluorochloroethylene and vinylidene fluoride, a tetrafluoroethylene telomer and a solvent for the copolymer and the telomer " 2. Lubricant according to claim 1, characterized in that it is a halogenated aliphatic solvent Contains hydrocarbon and that the copolymer in a concentration of at least about 0.005% by weight and that Telomere are present at a concentration of at least about 0.01% by weight. 3. Lubricant according to claim 2, characterized in that it contains trichlorotrifluoroethane as the solvent. 4. 'Lubricant according to one of claims 1, 2 or 3, characterized in that the tetrafluoroethylene telomer has a molecular weight between about 700 and about 4,000. 5. Lubricant according to claim 1, characterized in that the mixture of poly (trifluorochloroethylene-co-vinylidene fluoride) at a concentration of at least about 0.005% by weight and the telomere at a concentration of at least Contains about 0.01% by weight. 6. Lubricant according to claim 1, characterized in that the mixture of poly (trifluorochloroethylene-Co-viny.lidenfluorid) at a concentration of at least about 0.02% by weight and the telomere at a concentration of at least about Contains 0.1% by weight. 7. Lubricant according to one of the preceding claims, characterized in that the agent consists of a copolymer 709825/0858 Contains trifluorochloroethylene and vinyl chloride. 8. A method for lubricating substrates, characterized in that that a mixture is prepared which is a copolymer of trifluorochloroethylene and vinylidene fluoride Contains tetrafluoroethylene telomer and a solvent, the mixture applies to the substrate and under formation a slippery coating on the substrate removes the solvent from the mixture. 9. A method for lubricating substrates according to claim 8, characterized in that the treated substrate is polished after removal of the solvent. 10. A method for lubricating substrates according to claim or 9, characterized in that a solvent nalogenated aliphatic solvent used 11. A method for lubricating substrates according to claim 8, 9 or 10, characterized in that the tetrafluoroethylene telomer has a molecular weight between about and about 4000 that the copolymer is in the blend in a concentration of at least about 0.005 weight percent and the telomere in the mixture at a concentration of at least about 0.01% by weight are present. 12. A method for lubricating substrates according to claim 11, characterized in that the tetrafluoroethylene telomer has a molecular weight between about 800 and 3700. 13 · Method for lubricating substrates according to one of claims 8 to 12, characterized in that as Solvent trichlorotrifluoroethane is used. 709825/0858 - «τ. 262435Q , 3 14. A method for lubricating substrates according to any one of the preceding claims 8 to 13, characterized in that that the mixture contains a copolymer of trifluorochloroethylene and vinyl chloride. 15. A method for lubricating substrates according to any one of the preceding claims 8 to 14, characterized in that that the substrate is a phonographic recording material. 16. A method for lubricating substrates according to any one of the preceding claims 8 to 14, characterized in that that the substrate is a photographic film. 17 · Lubricated substrate, characterized in that it comprises: a substrate with a coating thereon which is a Contains copolymer of trifluorochloroethylene and vinylidene fluoride and a tetrafluoroethylene telomer. 18. Lubricated substrate according to claim 17, characterized in that that the substrate is a recording substrate. 19 Lubricated substrate according to Claim 17, characterized in that that the substrate is a photographic film. 20. Lubricated substrate according to claim 17, characterized in that that the substrate is a magnetic substrate. 21. Lubricated substrate according to claim 17, characterized in that that the substrate is a phonographic recording material. 709825/0858