KR20090031770A - Phosphazene compound, lubricant and magnetic recording medium having such compound, method of preparation, and method of lubrication - Google Patents

Abstract

(I) is provided, where R is selected from CF3, F, and H, and m is an integer from 1 to 22. The compound may be prepared by reacting a first reactant with a second reactant in a solution, where the first reactant is a 2,4-dichloro-2,4,6,6-tetra(aryloxy)-1,3,5-triaza-2,4,6-triphosphorine, and the second reactant is a perfluoropolyether of the formula CF3CF2CF2O(CF2CF2CF 2O)mCF2CF2CH2OH. The aryloxy is selected from 4-(trifluoromethyl)phenoxy (p-CF3-C6H4O), 4-fluorophenoxy (p-F-C6H4O), and phenoxy (C6H5O). The first reactant may be prepared by reacting 2,2,4,4,6,6-hexachloro-1,3,5-triaza-2,4,6-triphosphorine with a phenoxide. The compound may be used in a lubricant for lubricating a surface. The lubricant may be applied to a recording surface in a magnetic recording device including a recording medium.

Description

Phosphagen compounds, lubricants and magnetic recording media having such compounds, methods of manufacture and lubrication methods TECHNICAL FIELD

The present invention relates to a phosphazene compound, a method for preparing the compound, a lubricant and a magnetic recording medium having the compound, and a surface lubrication method.

Various phosphazene compounds have been used as lubricants, such as for magnetic recording applications. Some of the conventional phosphazene compounds include fluorinated or perfluoroalkyl aromatic groups and hydroxyl terminated perfluoropolyether (PFPE) chains. While these conventional phosphazene lubricants have been found to be useful in a variety of applications, alternative improved lubricants are still desirable. For example, compounds having reduced dynamic friction coefficients and improved thermal stability are desirable for lubricants used in magnetic recording applications such as heating magnetic recording (HAMR) devices that include recording media. Other desirable improvements to lubricants used in magnetic recording applications include improved corrosion resistance and good balanced mobility.

Thus, according to one aspect of the invention there is provided a compound of the formula:

Wherein R is selected from CF ₃ , F and H and m is an integer from 1 to 22, such as 10 to 12. In certain embodiments R is CF ₃ .

According to another aspect of the present invention, a method for preparing a compound described in the above paragraph is provided. The method includes reacting a first reactant with a second reactant in a solution to form a compound. The first reactant is 2,4-dichloro-2,4,6,6-tetra (aryloxy) -1,3,5-triaza-2,4,6-triphosphorin, and the second reactant is CF ₃ CF ₂ CF ₂ O (CF ₂ CF ₂ CF ₂ O) _m CF ₂ CF ₂ CH ₂ OH, a perfluoropolyether. The aryloxy is 4- (trifluoromethyl) phenoxy ( p -CF ₃ -C ₆ H ₄ O), 4-fluorophenoxy ( p -FC ₆ H ₄ O) and phenoxy (C ₆ H ₅ O). The solution may comprise a solvent comprising tetrahydrofuran. The solution may also include a perfluorinated solvent. The first reactant may be prepared by reacting 2,2,4,4,6,6-hexachloro-1,3,5-triaza-2,4,6-triphosphorine with phenoxide. The phenoxide can be prepared by reacting phenol with a base in solution. The base may be selected from sodium hydride, potassium hydroxide, potassium carbonate and sodium hydroxide. The compound contains 2,2,4,4,6,6-hexachloro-1,3,5-triaza-2,4,6-triphosphorine, the second reactant, phenol and sodium hydride in solution. It can be prepared by mixing, and the solution includes a perfluorinated solvent and tetrahydrofuran.

According to a further aspect of the invention, a surface lubrication method is provided. In this method, the effective amount of the compound described above is applied to the surface to smooth the surface. The surface may be a recording surface of a magnetic recording device. The magnetic recording device may be a magnetic recording medium. The magnetic recording medium is a rotating magnetic recording medium selected from a horizontal recording medium, a vertical recording medium, a patterned recording medium and a heat assisted magnetic recording medium. It may include.

According to a further aspect of the invention, there is provided a lubricant comprising the compound described above. The lubricant may be for a magnetic recording medium. The magnetic recording medium may include a rotating magnetic recording medium selected from a horizontal recording medium, a vertical recording medium, a pattern recording medium and a heated magnetic recording medium.

According to a further aspect of the present invention, there is provided a magnetic recording apparatus having a recording surface and the lubricant described above on the recording surface. The apparatus may be a magnetic recording medium. The magnetic recording medium may include a rotating magnetic recording medium selected from a horizontal recording medium, a vertical recording medium, a pattern recording medium and a heated magnetic recording medium. The magnetic recording device may include a hard disk drive.

Other aspects and features of the invention will become apparent to those skilled in the art upon review of the specific embodiments of the invention described below in conjunction with the accompanying drawings.

An exemplary embodiment of the invention is a compound of formula (I):

Wherein R is selected from CF ₃ , F and H, and m is an integer from 1 to 22. In certain embodiments R is CF ₃ . In some embodiments, m can be 1-10.

The compound of formula (I) is PFPE covalently bonded cyclotriphosphazene. Each compound of formula (I) has four substituted aromatic groups and two PFPE chains. The aromatic group is para-trifluoromethylphenoxy, para-fluorophenoxy or phenoxy group. The PFPE chain does not have terminal hydroxyl groups. According to the conventional nomenclature, the compound of formula (I) is 2,4-di (PFPE-O) -2,4,6,6-tetra (4- (trifluoromethyl) phenoxy) -1, 3,5-triaza-2,4,6-triphosphorin (if R is CF ₃ ), 2,4-di (PFPE-O) -2,4,6,6-tetra (4-fluoro Phenoxy) -1,3,5-triaza-2,4,6-triphosphorin (if R is F) and 2,4-di (PFPE-O) -2,4,6,6-tetra (Phenoxy) -1,3,5-triaza-2,4,6-triphosphorin, where R is H.

It has been found that the compounds of formula (I) can be used in lubricants and the resulting lubricants have improved properties and characteristics over conventional lubricants used in magnetic recording applications. For example, as discussed further below, lubricants containing these compounds may have relatively low dynamic coefficients of friction and relatively high thermal stability compared to some conventional lubricants. Lubricants according to embodiments of the invention may also have good corrosion resistance and balanced mobility.

Thus, in a representative embodiment of the present invention, there is provided a lubricant containing a phosphazene compound of formula (I). The lubricant may also contain other suitable chemicals or additives such as PFPE. The lubricant can be used in magnetic recording devices or applications. The lubricant may be applied to the recording surface of the magnetic recording medium. The magnetic recording device or application may use HAMR technology. As can be appreciated, for HAMR applications or devices, lubricants with high thermal stability can be advantageous, where the temperature at the recording surface of the HAMR device or media is within a nanosecond cycling period. It is because it can cycle between room temperature and the temperature of 250-650 degreeC. As can be appreciated, the lubricant can be used in any suitable magnetic recording application with a suitable recording medium or other device. For example, the lubricant may be used for a rotating magnetic recording medium including a horizontal recording medium, a vertical recording medium, a pattern recording medium, a heating magnetic recording medium, and the like.

Moreover, the lubricant can be used in other similar or different applications. For example, lubricants can be advantageously used in any suitable application where high thermal stability and low dynamic coefficient of friction are required.

1A shows a magnetic recording apparatus 100 that includes a magnetic recording medium 102 and a magnetic recording head 104. The magnetic recording device 100 may be a disk drive, such as a hard disk drive, in which the head 104 reads from and writes to the magnetic recording medium 102. As shown, the magnetic recording medium 102 may have the shape of a disc and may rotate around a central axis.

The magnetic recording medium 102 can have any suitable structure and can be made of any suitable material, as will be appreciated by those skilled in the art. An exemplary embodiment of the magnetic recording medium 102 is shown in FIG. 1B. As shown, the magnetic recording medium 102 may have a multi-layered structure, and a protective layer 112 such as a carbon overcoat having a substrate 106, an underlayer 108, a magnetic layer 110, and a surface 114. It includes. The write head 104 will move across the surface 114 to read and write data. Thus, the surface 114 is a recording surface written on a magnetic recording medium on which data is written from the recording medium. Lubricant containing an effective amount of the compound of formula (I) is deposited on the surface 114. The lubricant may be applied to the surface 114 using dip coating or vapor phase deposition. Surface 114 may be specially sputtered for good affinity for the lubricant. Other materials may be added to the lubricant as additives to further improve the performance of the lubricant. The lubricant may be applied to the surface 114 to form the thin film 116. The thin film 116 may have a thickness of 0.5 to 10 nm, such as about 1 to 2 nm.

Head 104 may be any suitable read / write head and may include a head-gimbal-assembly (HGA).

Device 100 may also include other components. For example, in a disk drive, a spindle motor (not shown) may be included to rotate the disk.

During use, the head 104 can be moved relative to the recording medium 102. For example, in a disk drive, the disk can be rotated so that other memory addresses can be accessed by the head 104. The head 104 may contact the lubrication film 116 during such relative movement. Since the film 116 has a low dynamic friction coefficient, the recording surface 114 is smoothed to reduce the friction between the recording surface 114 and the head 104.

It has also been found that the compound of formula (I) can be prepared by a representative embodiment of the present invention which is the following method. In the process, the compound of formula (I) selected is prepared by reacting the first reactant and the second reactant in solution. The first reactant is 2,4-dichloro-2,4,6,6-tetra (aryloxy) -1,3,5-triaza-2,4,6-triphosphorin, wherein the aryloxy is formed Phenoxy (C ₆ H ₅ O), 4-fluorophenoxy ( p -FC ₆ H ₄ O) and 4- (trifluoromethyl) phenoxy ( p -CF ₃ -C ₆ H ₄ depending on the compound being O). The second reactant is a perfluoropolyether in the form of R _f OH with one terminal hydroxyl group. R _f has the formula CF ₃ CF ₂ CF ₂ O (CF ₂ CF ₂ CF ₂ O) _m CF ₂ CF ₂ CH ₂ , where m is an integer from 1 to 22, such as 10 to 12. As can be appreciated, R _f OH has a molecular weight of about 400 to about 4000. The "m" value can be selected depending on the resultant compound required.

The solution may comprise two immiscible solvents such as tetrahydrofuran (THF) and perfluorinated solvents. The THF may be replaced with another suitable solvent such as benzene, methylbenzene and the like. The perfluorinated solvent may be selected from FC-77 ™, HFE 7100 ™, PF 5060 ™, and the like. Some of these solvents are commercially available from Dupont ™ or 3M ™ Novec ™. Suitable solvents for Vertrel ™ solvents may also be used.

The first reactant can be prepared by reacting a third reactant with a corresponding phenoxide in solution, wherein the third reactant is 2,2,4,4,6,6-hexachloro-1,3,5-tri Aza-2,4,6-triphosphorin. The phenoxide can be prepared by reacting phenol with a base. The base may be selected from sodium hydride, potassium hydroxide, sodium hydroxide, potassium carbonate and the like. In one particular representative embodiment, the base is sodium hydride.

In certain representative embodiments, the compound of formula (I) may be prepared by mixing the second and third reactants, the corresponding phenol and sodium hydride in a solution having a perfluorinated solvent and THF as solvent. The reaction in solution is expected to proceed as shown in Figure 2, where R is CF ₃ , F or H. The phenol and sodium hydride react in solution to form the corresponding phenoxide. Then, as shown in the first reaction of FIG. 2, the phenoxide reacts with the third reactant to form the first reactant. The first reactant formed reacts with the second reactant (R _f OH) in the presence of sodium hydride (NaH) to form the desired phosphazene compound, as shown in the second reaction of FIG. 2. The phosphazene compound can then be extracted from the solution. As can be appreciated by those skilled in the art, conventional purification techniques can be used in the synthesis of the compounds.

It can be appreciated that the first reaction step of FIG. 2 can be carried out in THF, benzene or methylbenzene. For example, the first reaction step can be performed in THF. The product of the first reaction, extracted from the first solution and purified, is then reacted with R _f OH in the presence of NaH in a mixture of perfluorinated solvent and THF. On the other hand, the perfluorinated solvent and R _f ONa can be added to the THF solution with the purified tetra-substituted intermediate obtained from the first step.

As can be appreciated, in the exemplary procedure described above, the ratio of the number of substituted aromatic groups and the number of PFPE chains in the resulting compound is suitably adjusted to exactly 4: 2.

Compounds of formula (I) can be readily formed and introduced into the lubricant by those skilled in the art using suitable techniques including conventional lubricant preparation techniques. Likewise, any suitable technique for applying lubricant to a magnetic recording medium or device, including techniques known to those skilled in the art, can be used to apply the lubricant of the present invention to a magnetic recording medium or device.

In an exemplary process of forming a thin lubricating film on a surface, diluents can be prepared by dissolving the lubricant compound in a suitable solution such as PF5060, HFE7100, or a suitable solvent in a Vertrel solvent. When the recording medium is immersed in the liquid and then taken out of the liquid, the surface of the recording medium is coated with the liquid. The coated fluid is dried. Once the solvent has evaporated sufficiently, a layer of lubricant remains on the media surface. The thickness of the lubricant layer can be adjusted by adjusting the concentration or immersion rate of the lubricant compound in the liquid, or both.

After further describing an exemplary embodiment of the present invention, some specific embodiments are disclosed.

In the drawings showing embodiments of the invention by way of example only,

1A is a schematic top plan view of a magnetic recording apparatus including a magnetic recording medium;

FIG. 1B is a schematic side view of the magnetic recording medium of FIG. 1A; FIG.

2 is a schematic diagram of a chemical reaction process;

3 and 4 are line graphs of weight loss, respectively measured as temperature functions for different lubricants;

5 is a line graph of friction coefficients measured for different lubricants;

6A and 6B are bar graphs of corrosion products measured for different lubricants;

7-9 are line graphs showing surface images showing lubrication film resilience for different lubricants, respectively, measured by time-of-flight secondary ion mass spectrometry (TOF-SIMS); And

10 is a bar graph of the contact angle of water measured for different lubricants.

Example I :

In Example I, 2,4-dichloro-2,4,6,6-tetra (4- (trifluoromethyl) phenoxy) -1,3,5-triaza-2,4,6-triphosphorine Was synthesized in the following order.

A first solution was prepared containing 200 mL of dry THF and 20.0 g (123.37 mmol) of 4- (trifluoromethyl) phenol. About 4.94 g sodium hydride (123.43 mmol as a 60% dispersion in mineral oil) was added to the first solution in small proportions to form sodium 4- (trifluoromethyl) phenoxide.

The second solution is 10.72 g (30.84 mmol) of 2,2,4,4,6,6-hexachloro-1,3,5-triaza-2,4,6-triphosphorine in 100 ml dry THF. It was prepared at approximately room temperature by dissolving it.

A mixture was formed by dropwise addition of sodium 4- (trifluoromethyl) phenoxide formed from the first solution to the second solution at 0 ° C. The mixed solution was stirred while adding sodium 4- (trifluoromethyl) phenoxide.

The mixture was warmed to rt and stirred for 24 h. THF in the mixture was then removed from the mixture by rotary evaporation. The oily residue was dissolved in chloroform and washed sequentially with water, dilute aqueous hydrochloric acid, water and brine to remove unreacted starting material and water soluble side reactions.

The remaining water in the chloroform layer is then removed with anhydrous MgSO ₄ as a desiccant. After drying, the precursor was filtered off and the chloroform was removed under reduced pressure, resulting in a crude liquid product.

The crude liquid product is 2,4,6-trichloro-2,4,6-tri (4- (trifluoromethyl) phenoxy) -1,3,5-triaza-2,4,6-tri Phosphorin, 2,4-dichloro-2,4,6-tetra (4- (trifluoromethyl) phenoxy) -1,3,5-triaza-2,4,6-triphosphorine and 2- Chloro-2,4,4,6,6-penta (4- (trifluoromethyl) phenoxy) -1,3,5-triaza-2,4,6-triphosphorin. The composition of the crude product was analyzed using thin layer chromatography.

The crude product was purified by column chromatography using a 1: 3 volumetric mixture of chloroform / hexanes as eluent. The purified product is 2,4-dichloro-2,4,6,6-tetra (4- (trifluoromethyl) phenoxy) -1,3,5-triaza-2,4,6-triforce It contained porin and was a viscous liquid. The resulting product weighed about 11.67 g and was produced in a yield of about 45%.

Example II :

In Example II, 2,4-dichloro-2,4,6,6-tetra (4-fluorophenoxy) -1,3,5-triaza-2,4,6-triphosphorine was Synthesized.

A first solution was prepared by adding 13.50 g (120.4 mmol) of 4-fluorophenol to 100 mL of dry THF. About 4.90 g sodium hydride (122.5 mmol as a 60% dispersion in mineral oil) was added to the first solution in small proportions to form sodium 4-fluorophenoxide.

The second solution was 2,2,4,4,6,6-hexachloro-1,3,5-triaza-2,4,6-triphosphorin (10.0 g, 28.8 mmol) in 100 mL dry THF. It was prepared by adding.

Sodium 4-fluorophenoxide formed from the first solution was added dropwise to the second solution at 0 ° C. to form a mixture. While adding, the second solution was stirred.

The mixture was advanced in the same manner as in Example I to obtain a crude product. The crude product is 2,4,6-trichloro-2,4,6-tri (4-fluorophenoxy) -1,3,5-triaza-2,4,6-triphosphorin, 2, 4-dichloro-2,4,6-tetra (4-fluorophenoxy) -1,3,5-triaza-2,4,6-triphosphorine and 2-chloro-2,4,4,6 , 6-penta (fluorophenoxy) -1,3,5-triaza-2,4,6-triphosphorin. The composition of the crude product was analyzed using thin layer chromatography. The crude product was purified in the same manner as in Example I. The purified product contained 2,4-dichloro-2,4,6,6-tetra (4-fluorophenoxy) -1,3,5-triaza-2,4,6-triphosphorin It was a colorless liquid. About 9.52 g of product was obtained, yielding about 51% yield.

Example III :

In Example III, 2,4-dichloro-2,4,6,6-tetra (phenoxy) -1,3,5-triaza-2,4,6-triphosphorin was synthesized in the following order.

A first solution was prepared by adding 22.74 g (241.62 mmol) of phenol to 100 mL of dry THF. About 9.66 g sodium hydride (241.62 mmol as 60% dispersion in mineral oil) was added to the first solution in small proportions to form sodium phenoxide.

The second solution is 20.0 g (57.53 mmol) of 2,2,4,4,6,6-hexachloro-1,3,5-triaza-2,4,6-triphosphorine in 50 ml of dry THF. It was prepared by adding.

Sodium phenoxide formed from the first solution was added dropwise to the second solution at 0 ° C. to form a mixture. The solution was stirred while adding.

The mixture was advanced in the same manner as in Example I to obtain a crude product. The crude product is 2,4,6-trichloro-2,4,6-tri (phenoxy) -1,3,5-triaza-2,4,6-triphosphorine, 2,4-dichloro- 2,4,6-tetra (phenoxy) -1,3,5-triaza-2,4,6-triphosphorine and 2-chloro-2,4,4,6,6-penta (phenoxy) -1,3,5-triaza-2,4,6-triphosphorin. The composition of the crude product was analyzed using thin layer chromatography. The crude product was purified in the same manner as in Example I. The purified product contained 2,4-dichloro-2,4,6,6-tetraphenoxy-1,3,5-triaza-2,4,6-triphosphorin and was a colorless liquid. About 17.5 g of product were obtained, resulting in a yield of about 53%.

Example IV :

In Example IV, lubricant I, a lubricant, was synthesized.

50 ml FC-77 ™ fluid was dried through 4-mm molecular sieve and added to a 100 ml flask. The flask was equipped with a magnetic stirrer, a reflux cooler and a dropping funnel. About 0.15 g sodium hydride (60% dispersion in mineral oil) was added to the flask in small proportions. About 8.05 g of dried hydroxyl terminated PFPE was added to the flask. The resulting suspension in the flask was vigorously stirred at room temperature for 24 hours.

Approximately 1.50 g of 2.4-dichloro-2,4,6,6-tetra (4- (trifluoromethyl) phenoxy) -1,3,5-triaza-2,4,6-triphosphorine was administered Prepared as disclosed in Example I and dissolved in 50 ml dry THF. The resulting solution was added dropwise to the flask at room temperature. The mixture in the flask was then stirred at room temperature for 24 hours and then refluxed at 75 ° C. for 3.5 hours.

FC-77 and THF contents in the flask were removed under reduced pressure. Deionized water was poured into the residue in the flask and the mixture was stirred for 30 minutes. The resulting mixture was transferred to a plastic tube and centrifuged to remove water. The water removal process was performed repeatedly to remove sodium chloride formed during the steps described in the paragraph above. The residue in the flask was dried under vacuum to remove traces of water. Excess hydroxyl terminal perfluoropolyether was also removed by vacuum distillation. The resulting product (about 6.5 g, 70% yield) was classified as lubricant I.

Example Ⅴ :

In Example V, lubricant II, a second sample lubricant, was synthesized.

The synthesis process used about 0.141 g sodium hydride and about 9.0 g dried hydroxyl terminated PFPE to prepare a suspension, 1.15 g of 2,4-dichloro-2, prepared as described in Example II, Examples 4 and 6, except that 4,6,6-tetra (4-fluorophenoxy) -1,3,5-triaza-2,4,6-triphosphorine were used to prepare lubricant II, a lubricant Similarly. The product weighed 5.70 g and was produced in about 63% yield.

Example VI :

In Example VI, lubricant III, another sample lubricant, was synthesized.

Lubricant III used about 8.0 g of dried hydroxyl terminated PFPE to prepare the suspension and 0.82 g of 2,4-dichloro-2,4,6,6-tetra (phenoxy) prepared as in Example III. C) -1,3,5-triaza-2,4,6-triphosphorine was similar to Example V except that lubricant 1, which was used as lubricant, was prepared to prepare lubricant III (about 3.2 g, 45% yield).

Example Ⅶ :

In Example VII, thin lubricated nanofilms (films with nanometer-sized thicknesses) were prepared from lubricants I to III, respectively, using dip coating. The dip coating solution contained a respective lubricant and PF5060 solvent. The film thickness was adjusted by varying lubricant concentration and dipping / ejection rate. The uniformity of the film was measured using an optical surface analyzer (OSA). The film made from lubricant I was measured to have a thickness of about 1.2 nm.

In this example, the compound for the third reactant used was recrystallized from ethyl acetate before use. The THF used was treated with metallic sodium and distilled before use. Phenols, 4-fluorophenols, 4- (trifluoromethyl) phenols and other chemicals were used from Sigma-Aldrich ™ having a 99% purity grade. Hydroxyl-terminated PFPE (Demnum SA) is commercially available from Daikin ™ Industries.

Comparative study :

Several properties of lubricants I to III were measured and compared with conventional lubricants. Conventional lubricants used in this comparative study were Zdol 2000 ™ and AM 3001 ™ obtained from Solvay Solexis ™, and A20H ™ obtained from Moresco ™.

Degradation test results showed that both Zdol 2000 and AM 3001 lubricants degraded more during laser radiation than indicated by lubricant I. Conventional lubricants have started to degrade significantly at much lower temperatures. The results measured for Lubricant I (solid line) and Zdol 2000 lubricant (dashed line) are shown in FIGS. 3 (in nitrogen) and 4 (in air). Table 1 lists the measured thermal stability for various lubricants. Thermal stability of the test lubricant was evaluated using thermogravimetric analysis (TGA). The decomposition temperature (T _d ) was considered to be the temperature at which 5% weight loss occurred after heating. As can be seen from Table 1, lubricants I to III have much greater thermal stability than Zdol 2000 lubricants. For example, the decomposition temperature of lubricant I is 125 ° C. and 145 ° C. higher in air and nitrogen than Zdol 2000 lubricant, respectively.

TABLE 1 Thermal Stability (T _d )

slush T _{d in the} air T _{d in} nitrogen Lubricant Ⅰ 301 328 Lubricant Ⅱ 273 298 Lubricant Ⅲ 262 274 Zdol 2000 176 183

In addition, it was observed that the nanofilm formed from lubricant I by optical surface analysis showed excellent uniformity. In comparison, Zdol 2000 and AM 3001 showed significant nonuniformity under the same deposition conditions. These results suggest that lubricant I had better film formability than both Zdol 2000 and AM 3001.

The dynamic coefficients of friction of the thin films formed from lubricants I to III and Zdol 2000 and A20H lubricants were measured. The film was formed on the surface of a magnetic hard disk and measured using a VINA ™ contact start stop (CSS) tester attached to an OSA 5100 ™ optical surface analyzer (-1.36 ° skew angle and 2.5 g vertical load). . As shown in FIG. 5, the results showed that lubricant I had a lower coefficient of dynamic friction than conventional lubricants tested.

Lubricant I also exhibited high corrosion resistance as shown in FIGS. 6A and 6B. 6A and 6B show the amount of corrosion product (Ni or Co) detected on a magnetic media surface smoothed with each tested lubricant after treatment of the smoothed surface with a 0.5M acrylic acid solution at 60 ° C. for 48 hours, respectively. Shows. The measurement was performed using TOF-SIMS. As can be seen, the resulting comparative lubricant produced much more corrosion products than lubricant I under the same test conditions.

Lubrication mobility was also tested. In this test, each lubricant film was initially formed uniformly on the disk surface. Local areas in the film (radial “stripes” approximately 10-15 μm wide) were depleted of lubricant. The rate at which each lubrication film flowed back to the depleted area on the disk surface was measured using TOF-SIMS. Some example results are shown in FIGS. 7 (for A20H), FIG. 8 (Zdol 2000) and 9 (for Lubricant I), which show the resilience of each lubricant in the depleted area after 40 minutes. Indicated. The mobility of the A20H film was found to be much lower than that of the Zdol 2000 film: the A20H film appeared to have little restorability, while the Zdol 2000 film showed perfect recovery. In comparison, lubricant I exhibited moderate mobility. As can be appreciated, excessive mobility can cause lubricant spin-off and lubrication film dewetting, reducing the durability of the hard disk, while insufficient mobility lubricates some areas on the disk surface. It may cause a loss. Thus, moderate mobility is desirable for lubricants used in magnetic recording applications.

The water contact angle of the lubricant was also measured using a RameHart ™ contact angle goniometer. As shown in FIG. 10 showing that lubricant I has a low surface energy, under the same measurement conditions, the water contact angle of lubricant I was found to be greater than Zdol 2000 and A20H. It can be appreciated that lubricants having contact angles in the range of about 70 ° to about 90 ° or more may be desirable in various applications.

The compounds and lubricants described above may also include applications in different fields, including high speed motors, high performance vacuum pumps, automotive components, devices for use under extreme environmental conditions such as space development devices, and the like.

Other features, advantages, and effects described herein that are not expressly described above may be understood from this specification and drawings by those skilled in the art.

The contents of each reference cited above are hereby incorporated by reference.

Of course, the embodiments described above are intended to be illustrative only and are not intended to be limiting at all. The embodiments described above are subject to various modifications to the form, arrangement of components, details and order of action. The invention is rather intended to embrace all variations within that scope, as defined by the claims.

Claims (19)

Compound of the formula

Where R is selected from CF ₃ , F and H, and m is an integer from 1 to 22. The method according to claim 1, M is 10 to 12. The method according to claim 1 or 2, R is CF ₃ . A method for producing the compound of any one of claims 1 to 3, The method comprises reacting a first reactant with a second reactant in a solution to form the compound, The first reactant is 2,4-dichloro-2,4,6,6-tetra (aryloxy) -1,3,5-triaza-2,4,6-triphosphorin, The second reactant is a perfluoropolyether of the formula CF ₃ CF ₂ CF ₂ O (CF ₂ CF ₂ CF ₂ O) _m CF ₂ CF ₂ CH ₂ OH, The aryloxy is 4- (trifluoromethyl) phenoxy ( p -CF ₃ -C ₆ H ₄ O), 4-fluorophenoxy ( p -FC ₆ H ₄ O) and phenoxy (C ₆ H ₅ O) selected from. The method according to claim 4, Wherein said solution comprises a solvent comprising tetrahydrofuran. The method according to claim 5, The solution comprises a perfluorinated solvent. The method according to any one of claims 4 to 6, The method comprises the steps of reacting 2,2,4,4,6,6-hexachloro-1,3,5-triaza-2,4,6-triphosphorine with phenoxide to prepare the first reactant. How to include. The method according to claim 4, The process comprises 2,2,4,4,6,6-hexachloro-1,3,5-triaza-2,4,6-triphosphorine, the second reactant, phenol and sodium hydride in solution Mixing, wherein the solution comprises a perfluorinated solvent and tetrahydrofuran. A surface lubrication method comprising applying a effective amount of a compound of any one of claims 1 to 3 to the surface to smooth the surface. The method according to claim 9, The surface is a recording surface of a magnetic recording device. The method according to claim 10, And the magnetic recording device is a magnetic recording medium. The method according to claim 11, The magnetic recording medium is a rotating magnetic recording medium selected from a horizontal recording medium, a vertical recording medium, a patterned recording medium and a heat assisted magnetic recording medium. How to include. A lubricant comprising the compound of any one of claims 1 to 3. A lubricant for magnetic recording media comprising the lubricant of claim 13. The method according to claim 14, And the magnetic recording medium comprises a rotating magnetic recording medium selected from a horizontal recording medium, a vertical recording medium, a pattern recording medium and a heating magnetic recording medium. A magnetic recording medium having a recording surface and a lubricant on the recording surface, wherein the lubricant comprises the compound of any one of claims 1 to 3. The method according to claim 16, And the magnetic recording medium comprises a rotating magnetic recording medium selected from a horizontal recording medium, a vertical recording medium, a pattern recording medium and a heating magnetic recording medium. A magnetic recording apparatus comprising the magnetic recording medium of claim 16 or 17. The method according to claim 18, Magnetic recording device comprising a hard disk drive.

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