Deposition compositions and methods of making and using same

Abstract

The deposition composition includes a solvent containing a hydrofluorothioether compound represented by the following general formula (I): Rf-S-Rh (I), where Rf is a fluorinated or perfluorinated group having 2 to 9 carbon atoms, optionally containing one or more linearly linked heteroatoms or chlorine atoms, and Rh is a non-fluorinated hydrocarbon group having 1 to 3 carbon atoms. The deposition composition further includes a coating material that is soluble or dispersible in the solvent.

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates to deposition or carrier solvent solutions and methods for using same to coat substrates. [Background technology]

[0002] Various deposition or carrier solvent solutions are described, for example, in US Pat. Nos. 7,691,282, 6,403,149, and 5,049,410. DETAILED DESCRIPTION OF THE INVENTION

[0003] In deposition or carrier solvent applications, a solute is dissolved, emulsified, suspended, or otherwise disposed in a solvent to form a solution. The solution is then applied to a substrate, after which the solvent is evaporated or otherwise removed, leaving the solute on the substrate (e.g., in the form of a thin film or coating). Application of the solution to the substrate can be carried out using a number of techniques, including dip or drain coating, spin coating, spray coating, or roll-to-roll coating. Solvents used in these applications and techniques require a balance of properties, including the following: Solubility of deposited materials / solutes Ability to wet the substrate being coated - low surface tension and low viscosity of solvents and solutions Complete evaporation from the substrate - no solvent residue left behind Material compatibility - the solvent must be compatible with the solute, substrate, and materials used in the solution preparation and deposition process Stability - the solvent must be stable under the conditions of solution preparation and use. Safety – the solvent should be non-toxic / low-toxic and non-flammable · Environmentally friendly - the solvent should have a short atmospheric lifetime, low global warming potential (GWP) and no ozone depletion potential (ODP).

[0004] Solvent blends may be an option in some cases where a solvent, typically a fluorinated solvent, has the desired properties for deposition but lacks sufficient solubility for the solute. In such cases, the solvent may be blended with an organic solvent that has a higher affinity for the solute but does not itself possess the desired properties of a deposition solvent. Some examples of these co-solvents include alcohols, including isopropanol, and trans-1,2-dichloroethylene. While these systems can be made to work in some cases, such solvent blends have several drawbacks, including: Composition changes upon natural evaporation from the bath affect performance characteristics, including solute solubility (e.g., natural evaporation of one component from a mixture imparts changes in properties compared to a solution), safety, and quality of the deposited solute film (e.g., when the ratio of the solvent blend is changed, the solubility of the solute in the solvent blend changes, which affects the amount of solute absorbed onto the substrate). Potential material compatibility issues with added solvents Environmental regulations for added solvents ·Increased solubility for other undesirable solutes.

[0005] As a result, a single solvent solution that can balance the property requirements outlined above for a wide variety of solutes is desirable.

[0006] In general, this application is directed to the use of certain hydrofluorothioethers as deposition or carrier solvents. Surprisingly, it has been discovered that such hydrofluorothioethers have strong solubility for several important solutes, including perfluoropolyether (PFPE) lubricants, silicones, and fluoropolymers, while also providing a balance of properties that meet most, if not all, of the requirements outlined above. The excellent wetting properties of these solvents, combined with their environmental, physical, and safety properties in a single solvent system, make them ideal for use in numerous applications.

[0007] As used herein, "fluoro-" (e.g., with respect to a group or moiety, such as in "fluoroalkylene" or "fluoroalkyl" or "fluorocarbon") or "fluorinated" means partially fluorinated so that there is at least one hydrogen atom bonded to a carbon.

[0008] As used herein, "perfluoro" (e.g., with respect to a group or moiety, such as in "perfluoroalkylene" or "perfluoroalkyl" or "perfluorocarbon") or "perfluorinated" means completely fluorinated, and unless otherwise indicated, fully fluorinated such that there are no carbon-bonded hydrogen atoms available for replacement with fluorine.

[0009] As used herein, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification and the accompanying embodiments, the term "or" is generally used in its sense including "and / or" unless the content clearly dictates otherwise.

[0010] As used herein, the recitation of numerical ranges by endpoints includes all numbers subsumed within that range (eg, 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.8, 4, and 5).

[0011] Unless otherwise indicated, all numbers expressing quantities or ingredients, measurements of properties, and the like used in the specification and embodiments are to be understood as being modified in all instances by the term "about." Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing specification and accompanying list of embodiments may vary depending upon the desired properties sought to be obtained by one of ordinary skill in the art utilizing the teachings of the present disclosure. At the very least, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques; this is not intended to limit the application of the doctrine of equivalents to the scope of the claimed embodiments.

[0012] In some embodiments, the present disclosure is directed to deposition compositions that include one or more hydrofluorothioether compounds and a solute (or material otherwise dispersed in the hydrofluorothioether and intended for deposition onto a substrate).

[0013] In some embodiments, suitable hydrofluorothioethers have the following structural formula (I): Rf-S-Rh (I) is expressed by

[0014] In some embodiments, Rf is a partially or fully fluorinated group having 2 to 9, 2 to 6, 2 to 5, or 2 to 4 carbon atoms that is saturated or unsaturated, straight or branched, acyclic or cyclic, and optionally contains one or more catenated heteroatoms, chlorine atoms, or bromine atoms. In some embodiments, Rf is partially fluorinated. In some embodiments, Rf has two or fewer hydrogen atoms. In some embodiments, Rf is fully fluorinated. In some embodiments, Rf is a fully fluorinated saturated branched group having 3 to 6 carbon atoms.

[0015] In some embodiments, Rh is a saturated or unsaturated, straight or branched chain, non-fluorinated hydrocarbon group having 1 to 3 or 1 to 2 carbon atoms, optionally containing one or more catenated heteroatoms. In some embodiments, Rh is CH3 or CH3CH2. In some embodiments, Rh is CH3.

[0016] In some embodiments, suitable hydrofluorothioethers have the following structural formula (II): [ka] is expressed by

[0017] In some embodiments, n is 0 or 1, m is 0 or 1, X is an oxygen atom or a sulfur atom, Y is an oxygen atom or a sulfur atom, provided that both X and Y are not oxygen atoms, and R1, R2, R3, and R4 are independently a fluorine atom or a partially or fully fluorinated group having 1 to 4 or 1 to 3 carbon atoms, which is saturated or unsaturated, straight or branched, acyclic or cyclic, and optionally contains one or more chain-linked heteroatoms, chlorine atoms, or bromine atoms. In some embodiments, at least one of R1, R2, R3, and R4 is a partially fluorinated group having 1 to 4 carbon atoms. In some embodiments, R1, R2, R3, and R4 are independently a fluorine atom or a fully fluorinated group having 1 to 4 carbon atoms. In some embodiments, none of R1, R2, R3, and R4 has more than two hydrogen atoms.

[0018] In some embodiments, any of the chained heteroatoms discussed above may be a secondary O heteroatom, where O is bonded to two carbon atoms. In some embodiments, any of the chained heteroatoms discussed above may be a tertiary N heteroatom, where N is bonded to three carbon atoms.

[0019] In some embodiments, the fluorine content of the hydrofluorothioether compounds of the present disclosure may be sufficient to render the compounds non-flammable according to the ASTM D-3278-96 e-1 test method ("Small-scale Closed Apparatus Flash Point of Liquids").

[0020] In various embodiments, representative examples of compounds of general formula (I) include: CF3CF2-S-CH3, HCF2CF2-S-CH3, HCFClCF2-S-CH3, CF2ClCF2-S-CH3, CF3CFCl-S-CH3, CF3CF2CF2-S-CH3, CF3OCF2CF2-S-CH3, CF3CHFCF2-S-CH3, (CF3)2CF-S-CH3, (CF3)2CF-S-CH2Cl, CF3CF2CF2CF2-S-CH3, (CF3)2CFCF2-S-CH3, CF3CF2CF(CF3)-S-CH3, CF3OCF2CF2CF2-S-CH3, CF3CF2CF2CF2-S-CH2CH3, CF3CF2CF2CF2-S-CH2OCH3, CF3CF2CF(CF3)-S-CH2CH3, (CF3)2NCF2-S-CH3, [ka]

[0021] In various embodiments, representative examples of compounds of general formula (II) include: [ka]

[0022] In some embodiments, the hydrofluorothioethers of the present disclosure may be synthesized in a one-step process by i) the reaction of a perfluoroalkyl iodide with a dialkyl sulfide or dialkyl disulfide and an alkali metal alkanethiolate under UV or thermal conditions, as disclosed in U.S. Pat. No. 3,816,277, or ii) the reaction of a perfluoroalkyl anion generated from a perfluoroalkene with a metal fluoride (MF), or Rf-I or Rf-Br with Rh-SCN, as disclosed in J. Org. Chem., 1981, 46(9), 1938. In some embodiments, the hydrofluorothioethers of the present disclosure may be synthesized in a one-step process by the reaction of a perfluorinated olefin with sulfur in a catalytic amount of MF to form a cyclic dithietane (e.g., as disclosed in J. Org. Chem., 1982, 47(2), 377), followed by alkylation with a suitable alkylating reagent (e.g., as disclosed in Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya 1989, 6, 1380-3) in a two-step process.

[0023] In some embodiments, the hydrofluorothioethers of the present disclosure can be synthesized via the methods described in U.S. Pat. No. 3,749,794 and / or Russ. Chem. Bull., 1985, 34, 1906, which are incorporated herein by reference in their entireties.

[0024] In some embodiments, one or more of the above hydrofluorothioether compounds may be included in the deposition composition in an amount of at least 50 wt%, at least 70 wt%, at least 90 wt%, at least 95 wt%, or at least 99 wt%, based on the total weight of the composition. In some embodiments, the deposition composition may also include one or more additional solvents (e.g., ethers, alkanes, alkenes, perfluorocarbons, perfluorinated tertiary amines, perfluoroethers, cycloalkanes, esters, ketones, aromatic compounds, siloxanes, hydrochlorocarbons, hydrochlorofluorocarbons, hydrofluorocarbons, etc., and mixtures thereof). Such cosolvents are preferably at least partially fluorinated and can be selected to modify or improve the properties of the composition for a particular application, and can be utilized in a ratio (cosolvent to hydrofluorothioether) such that the resulting composition preferably has no flash point. For example, such additional solvents may be present in the deposition composition, but in an amount of less than 10 wt%, less than 5 wt%, or less than 1 wt%, based on the total weight of the deposition composition. In some embodiments, the deposition composition can consist essentially of one or more of the above hydrofluorothioether compounds and one or more solutes. For each application, small amounts of optional components can also be added to the compound to impart specific desired properties for a particular application. Useful compositions can also include conventional additives, such as surfactants, colorants, stabilizers, antioxidants, flame retardants, etc., and mixtures thereof.

[0025] In some embodiments, the hydrofluorothioether compounds may have a low environmental impact. In this regard, the hydrofluorothioether compounds of the present disclosure may have a global warming potential (GWP) of less than 500, less than 300, less than 200, less than 100, less than 50, less than 10, or less than 1. As used herein, GWP is a relative measure of a compound's global warming potential based on the compound's structure. The GWP of a compound was defined by the Intergovernmental Panel on Climate Change (IPCC) in 1990 and revised in 2007, and is calculated as the warming due to the emission of 1 kilogram of the compound relative to the warming due to the emission of 1 kilogram of CO2 over a specified integration time horizon (ITH).

number

[0026] In this formula, a i is the radiative forcing (the change in radiation flux through the atmosphere due to the IR absorbance of that compound) per unit mass increase of a compound in the atmosphere, C is the atmospheric concentration of the compound, τ is the atmospheric lifetime of the compound, t is time, and i is the compound of interest. A commonly accepted ITH is 100 years, which represents a compromise between short-term effects (20 years) and long-term effects (500 years or more). The concentration of an organic compound, i, in the atmosphere is assumed to follow pseudo-first-order kinetics (i.e., exponential decay). The concentration of CO2 over the same time interval incorporates a more complex model of the exchange and removal of CO2 from the atmosphere (the Bern carbon cycle model).

[0027] In some embodiments, the hydrofluorothioethers of the present disclosure can have an ozone depletion potential (ODP) of zero or near zero.

[0028] In some embodiments, the hydrofluorothioether provides excellent wetting properties, including low surface tension and low viscosity. In some embodiments, the surface tension of the hydrofluorothioether can be less than 25 dynes per centimeter (dyn / cm), or less than 20 dyn / cm, or less than 15 dyn / cm. In some embodiments, the viscosity of the hydrofluorothioether can be less than 2 centipoise (cps), or less than 1 cps.

[0029] In some embodiments, the hydrofluorothioether evaporates uniformly and completely from the substrate after the deposition process. Evaporation of the solvent is controlled by the boiling point and heat of vaporization of the solvent. In some embodiments, the boiling point of the hydrofluorothioether is less than 150 degrees Celsius (°C), less than 130°C, less than 100°C, or less than 80°C. In some embodiments, the heat of vaporization of the hydrofluorothioether is less than 50 calories per gram (cal / g), less than 40 cal / g, less than 35 cal / g, or less than 30 cal / g.

[0030] In various embodiments, the solute of the deposition composition (or material otherwise dispersed in the deposition composition and intended for deposition on a substrate) can include pigments, lubricants, stabilizers, adhesives, antioxidants, dyes, polymers, pharmaceuticals, archival materials (e.g., alkaline materials used to deacidify paper), release agents, inorganic oxides, and the like, and combinations thereof. For example, the coating material can include any one or combination of perfluoropolyethers, hydrocarbons, silicone lubricants, polymers or copolymers of various fluorocarbon or perfluorocarbon monomers (e.g., tetrafluoroethylene, vinylidene difluoride, fluorinated acrylates), or combinations thereof. Further examples of suitable coating materials include titanium dioxide, iron oxide, magnesium oxide, polysiloxane, stearic acid, acrylic adhesives, or combinations thereof.

[0031] In some embodiments, the deposition composition can include from 0.001 weight percent to 10 weight percent, from 0.1 weight percent to 10 weight percent, or from 0.1 weight percent to 5 weight percent of any one or combination of the above solutes, based on the total weight of the deposition composition.

[0032] Specific applications of the deposition compositions of the present disclosure include disk lubricants (PFPE lubricants) in the hard disk drive industry, needle deposition (silicones) in the medical industry, and deposition of fluoropolymer coatings for electrical components including printed circuit board assemblies (PCBAs) and sensors. Other applications include fingerprint developers or carrier solvents for particle deposition.

[0033] Further, with regard to disk lubricant applications, in hard disk drives, information is stored on a magnetic layer (also called the media) on the disk. This magnetic layer is protected by a diamond-like carbon (DLC) layer and a lubricant. The information in the magnetic layer on the media is read using a sensor in the head that "flies" over the media as it rotates. To improve the density of information stored on the media, one of the key parameters is the separation between the magnetic layer on the media and the sensor on the head. The thickness of the DLC and lubricant layer, along with the fly height of the head, determine this separation. A typically used lubricant is functionalized perfluoropolyether (PFPE). PFPE polymers are typically linear. Alcohol is a common functional group. Z-Dol (available from Solvay) has two alcohol groups and has been used as a lubricant by the HDD industry for many years: HOCH2CF2-(-OCF2CF2-) n -(-OCF2-) m -OCF2CH2OH The ratio of n to m is approximately 1, and the molecular weight can range from 1000 to 6000. New lubricants have been introduced to reduce the separation between the media magnetic layer and the head sensor, along with other performance needs. Some examples of these include Z-tetraol, which has four alcohol groups (available from Solvay): [ka] and ZTMD with eight alcohol groups (Journal of Applied Physics 100, 044306 (2006)). [ka] (Wherein Z is [ka] is) PFPE lubricants with six alcohol groups, along with molecules with other polar groups, are also being evaluated. As the polarity of lubricants used by the HDD industry increases, it becomes more difficult to find solvents that meet performance requirements. While commercially available single-solvent solutions of ZTMDs do not exist, the hydrofluorothioethers of the present invention provide such solutions due to their solubility in highly polar lubricants and other properties that meet the deposition solvent requirements already mentioned.

[0034] In some embodiments, the deposition compositions described above can be useful for depositing films or coatings, in which the hydrofluorothioether functions as a carrier (also referred to herein as a solute) for the coating material, enabling the material to be deposited on a substrate surface. In this regard, the present disclosure further relates to a method for depositing a coating on a substrate surface using the deposition compositions of the present disclosure. The method includes applying to at least a portion of at least one substrate surface a coating of a deposition composition comprising (a) a solvent composition comprising one or more hydrofluorothioether compounds described above, and (b) one or more coating materials soluble or otherwise dispersible in the solvent composition, and optionally, a co-dispersant, co-solvent, or additional additive described above. The coating can be of any desired thickness; in practice, the thickness will be determined by factors such as the viscosity of the coating material, the temperature at which the deposition composition is applied, and the withdrawal rate (if immersion is utilized). In exemplary embodiments, the deposition methods of the present disclosure can be carried out by applying the deposition composition to a substrate by any conventional technique. For example, the composition can be brushed or sprayed (e.g., as an aerosol) onto the substrate, or spin-coated onto the substrate. In some embodiments, the substrate may be coated by immersion in the composition. Immersion may be carried out at any suitable temperature and maintained for any convenient length of time. If the substrate is a tube, such as a catheter, and it is desired to ensure that the composition coats the lumen wall, the composition may be drawn into the lumen by application of reduced pressure.

[0035] The method may further include removing the solvent composition from the coating, for example, by evaporation (evaporation may be assisted, for example, by the application of heat or vacuum).

[0036] Both organic and inorganic substrates can be coated by the method of the present disclosure. Representative examples of substrates include metals, ceramics, glass, polycarbonate, polystyrene, acrylonitrile-butadiene-styrene copolymers, natural fibers (and fabrics derived from natural fibers), such as cotton, silk, fur, suede, leather, linen, and wool, synthetic fibers (and fabrics), such as polyester, rayon, acrylic, nylon, or blends thereof, fabrics containing blends of natural and synthetic fibers, and composites of the aforementioned materials. In some embodiments, substrates that can be coated include, for example, magnetic hard disks containing perfluoropolyether lubricants, medical devices with silicone lubricants, or electrical connectors with copolymers of various fluorocarbon or perfluorocarbon monomers.

[0037] Another aspect of the present disclosure provides a method for lubricating a substrate. The method includes applying a coating of a lubricant composition to the substrate, followed by removing the solvent from the coating to form a pure lubricant film. The lubricant composition can include 0.001% to 10% by weight of a perfluoropolyether lubricant or silicone lubricant and about 90.0% to about 99.99% by weight of the hydrofluorothioether compound, based on the weight of the lubricant composition. The hydrofluorothioether solvent can then be removed during a drying process. The substrate can be, for example, a magnetic medium, including thin films and hard disks, or medical devices. The magnetic medium can include a base layer, such as glass, aluminum, or a polymeric material, and a magnetic layer containing iron, cobalt, nickel, or the like. The magnetic medium can contain an optional layer of carbon or other materials, for example, to enhance the durability and performance of the medium. The lubricant can be applied as an outermost layer. [Example]

[0038] Objects and advantages of the present disclosure are further illustrated by the following comparative and illustrative examples. Unless otherwise noted, all parts, percentages, ratios, etc. in the examples and elsewhere in this specification are by weight, and all reagents used in the examples were obtained or are available from common chemical suppliers, such as Sigma-Aldrich Corp. (Saint Louis, MO, US), or can be synthesized by conventional methods. The following abbreviations are used herein: mL = milliliter, L = liter, mol = mole, mmol = millimole, min = minute, h = hour, g = gram, °C = degrees Celsius.

[0039] Sample preparation [Table 1]

[0040] Preparation of Example 1: Perfluoroisopropyl methyl thioether (PFIPTE) (CF3)2CFSCH3 A dry 600 mL Hastalloy Parr reactor was charged with sublimed sulfur (36 g, 1.1 mol), anhydrous spray-dried potassium fluoride (15 g, 260 mmol), and anhydrous N,N-dimethylformamide (300 mL). The reactor was sealed and the contents were heated to 60°C with stirring. Once the reactor was stabilized at this temperature, hexafluoropropene (150 g, 1.0 mol) was added at a rate of 6 g / min, maintaining the temperature below 65°C. Upon completion of the addition, the reaction was stirred at 60°C for 1 hour and then cooled to ambient temperature. The resulting slurry was transferred to a 2 L round-bottom flask to accommodate the addition of the remaining reagents. Potassium fluoride (116 g, 2.0 mol) was added in one portion, followed by dimethyl sulfate (104 mL, 1.1 mol) via the addition funnel at a rate that maintained the internal reaction temperature below 45°C. Once the addition was complete, the resulting reaction mixture was stirred at ambient temperature for 12 hours. The heterogeneous solution was then filtered to remove solids and then washed three times with an equal volume of water. The lower phase was collected, dried over magnesium sulfate, and filtered. The crude material was recovered as a pale yellow oil (117 g, 93% desired product by GC-fid). This material was purified by distillation at ambient pressure to give perfluoroisopropylmethyl thioether (98 g, 45% yield, boiling point = 65 °C).

[0041] solubility The solubility of Z-tetraol and ZTMD lubricants in PFIPTE (Example 1) and Comparative Examples CE1 and CE2 was determined at room temperature as follows: A glass vial with a PTFE-lined lid was weighed to four decimal points using a standard laboratory balance. The lubricant was added to the vial and the mass was recorded. Solvent was then added dropwise or incrementally to the vial until the lubricant was completely solubilized in the solvent. Once the lubricant was dissolved, the total weight of the container was measured, and the mass of the solvent was determined by subtracting the weight of the vial and lubricant. The weight percentage of the lubricant was calculated as the amount of lubricant divided by the total weight of the lubricant and solvent. Solubility was determined as the maximum weight percentage of the lubricant at which the lubricant was completely solubilized in the solvent. The results are shown in Table 2.

[0042] [Table 2]

[0043] The solubility of silicone and fluoropolymer lubricants in PFIPTE (Example 1) and Comparative Examples CE1 and CE3 was determined at room temperature as follows: An empty vial was placed on a standard laboratory balance and tared. Solvent was added to the vial and the weight was recorded. The desired lubricant solute was added to the vial and the mass of the solute was recorded. The vial was sealed, swirled, and the solubility was observed. If the solute was completely dissolved, additional solute was added, the mass was recorded, and the above steps were repeated. Addition of solute was continued until the solute was no longer soluble or the solubility was greater than 75% by weight. Solubility was determined as the weight percentage of the lubricant relative to the total weight of the lubricant and solvent.

[0044] [Table 3]

[0045] physical properties The boiling point and vapor pressure of Example 1 were determined using the procedures in ASTM E1719-97, "Standard Test Method for Vapor Pressure of Liquids by Ebulliometry." First, the vapor pressure was measured, and then the boiling point was calculated as described in Section 10 of ASTM Method E1719-97.

[0046] The heat of vaporization of Example 1 was calculated using vapor pressure data and the Clausius-Clapeyron equation.

[0047] Density was measured using a Rudolph DDM PLUS automatic density meter. Kinematic viscosity was determined using a ViscoSystem AVS350 viscosity timer (Schott Instruments GmbH, Hattenbergstraße 1055122 Mainz, Germany) and a Hagenbach-corrected 545-03, 545-13, or 545-20 Ubbelohde viscometer (Cannon Instruments Company, Box 812, State College, PA, US) according to ASTM D445-94e1 "Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (Calculation of Absolute Viscosity)," except that the bath temperature was controlled to ±0.1°C. For temperatures below 0°C, a Lawler temperature-controlled bath was used. Viscosity was calculated by multiplying the kinematic viscosity by the density.

[0048] Surface tension was determined at 24°C using a K100C force strength meter (available from Kruss, Hamburg, Germany). The method used the Wilhelmy plate technique according to ASTM D1331-14, "Standard Test Method for Interfacial Tension of Coating Solutions, Solvents, Surfactant Solutions, and Related Materials." Samples were tested in duplicate and reported as the average of two measurements.

[0049] The atmospheric lifetime of each test material was determined from relative rate studies utilizing chloromethane (CH3Cl) as the reference compound. The pseudo-first-order reaction rates of the reference and test compounds with hydroxyl radicals (·OH) were determined in a laboratory chamber system. The atmospheric lifetime of the reference compound has been reported in the literature. Based on this value and the pseudo-first-order rates measured in the chamber experiments, the atmospheric lifetime of each specimen was calculated from the reaction rate of the test compound relative to the reference compound and the reported lifetime of the reference compound shown below.

number

[0050] Global warming potential (GWP) values were calculated using the method described in the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5). Gas standards of the materials being evaluated, with known, documented concentrations, were prepared and used to obtain quantitative FTIR spectra of the compounds. Quantitative gas-phase, single-component FTIR library reference spectra at two different concentration levels were generated by diluting the sample standards with nitrogen using a mass flow controller. Flow rates were measured at the FTIR cell exhaust using a certified BIOS DRYCAL flow meter (Mesa Labs, Butler, NJ, US). The dilution procedure was also verified using a certified ethylene calibration gas cylinder. Using the method described in AR5, FTIR data was used to calculate radiative efficiencies, which were then combined with atmospheric lifetimes to calculate GWP values.

[0051] Flash points were measured according to the procedure outlined in ASTM D-3278-96 e-1, "Standard Test Method for Flash Point of Liquids in a Small-Scale Closed Apparatus." Materials exhibiting no flash point were considered non-flammable according to the ASTM test method.

[0052] The physical properties of Example 1 and Comparative Examples CE1 and CE2 are summarized in Table 4. Example 1 has evaporation (boiling point and heat of vaporization) and deposition (density, surface tension, and viscosity) properties comparable to CE1 and CE2, while possessing significantly lower GWP and improved solubility for solutes of interest (see Tables 2 and 3).

[0053] [Table 4]

[0054] Various modifications and alterations to the present disclosure will become apparent to those skilled in the art without departing from the scope and spirit of the disclosure. It is understood that the present disclosure is not intended to be unduly limited by the exemplary embodiments and examples set forth herein, and that such examples and embodiments are presented merely as examples within the scope of the present disclosure, which is intended to be limited only by the claims set forth herein as follows. All references cited in this disclosure are incorporated herein by reference in their entirety. The present invention includes the following aspects. (1) The following structural formula (I): Rf-S-Rh (I) (wherein Rf is a fluorinated or perfluorinated group having 2 to 9 carbon atoms, optionally containing one or more chain-linked heteroatoms or chlorine atoms, and Rh is a non-fluorinated hydrocarbon group having 1 to 3 carbon atoms). a solvent comprising a hydrofluorothioether represented by a coating material that is soluble or dispersible in said solvent; A deposition composition comprising: (2) The deposition composition of item 1, wherein the coating material comprises a pigment, a lubricant, a stabilizer, an adhesive, an antioxidant, a dye, a polymer, a pharmaceutical, a release agent, or an inorganic oxide. (3) The deposition composition of item 1, wherein the coating material comprises a perfluoropolyether, a hydrocarbon, a silicone lubricant, a fluorinated acrylate polymer, or a polymer or copolymer of a fluorocarbon or perfluorocarbon monomer. (4) The deposition composition according to any one of items 1 to 3, wherein Rf is a perfluorinated saturated group having 2 to 5 carbon atoms. (5) Rh is CH 3 or CH 3 CH 2 5. The deposition composition according to any one of items 1 to 4, (6) The deposition composition according to any one of items 1 to 5, wherein the compound having structural formula (I) is present in the deposition composition in an amount of at least 70 wt %, based on the total weight of the deposition composition. (7) A method for depositing a coating on a substrate, comprising: (a) applying a coating of the deposition composition according to any one of items 1 to 6 to a substrate; (b) removing the hydrofluorothioether from the coating; and A method comprising: (8) The method according to item 7, wherein the substrate is a magnetic hard disk, an electrical connector, or a medical device. (9) The following structural formula (I): Rf-S-Rh (I) (wherein Rf is a fluorinated or perfluorinated group having 2 to 9 carbon atoms, optionally containing one or more chain-linked heteroatoms or chlorine atoms, and Rh is a non-fluorinated hydrocarbon group having 1 to 3 carbon atoms). and a hydrofluorothioether represented by a lubricant soluble or dispersible in the hydrofluorothioether; A lubricant composition comprising: (10) based on the total weight of the lubricant composition, (a) 0.001 wt % to 10 wt % of a perfluoropolyether lubricant; (b) 90% to about 99.999% by weight of the hydrofluorothioether; 10. The lubricant composition according to item 9, comprising: (11) The lubricant composition according to item 10, wherein the perfluoropolyether lubricant comprises a perfluoropolyether compound having a polar group. (12) The lubricant composition according to item 11, wherein the polar group comprises an alcohol group. (13) The lubricant composition according to item 12, wherein the polar group comprises at least four alcohol groups. (14) A method for lubricating a substrate, comprising: (a) applying a coating of the lubricant composition according to any one of items 9 to 13 to a substrate; (b) removing the hydrofluorothioether from the coating; and A method comprising: (15) The method according to item 14, wherein the substrate is a magnetic medium. (16) The following structural formula (II):

change

Claims

1. The following structural formula (I): Rf-S-Rh (I) wherein Rf is a perfluorinated group having 2 to 9 carbon atoms, and Rh is a non-fluorinated hydrocarbon group having 1 to 3 carbon atoms. a solvent comprising a hydrofluorothioether represented by a coating material that is soluble or dispersible in said solvent; Including, The deposition composition wherein the coating material comprises a perfluoropolyether or a silicone lubricant.

2. The deposition composition of claim 1 , wherein the coating material comprises a pigment, a lubricant, a stabilizer, an adhesive, an antioxidant, a dye, a polymer, a pharmaceutical, a release agent, or an inorganic oxide.

3. 3. The deposition composition of claim 1, wherein Rf is a saturated perfluorinated group having 2 to 5 carbon atoms.

4. Rh is CH ３ or CH ３ CH ２ The deposition composition according to any one of claims 1 to 3, wherein

5. 5. The deposition composition of any one of claims 1 to 4, wherein the compound having structural formula (I) is present in the deposition composition in an amount of at least 70 wt%, based on the total weight of the deposition composition.

6. 1. A method of depositing a coating on a substrate, comprising: (a) applying a coating of the deposition composition of any one of claims 1 to 5 to a substrate; (b) removing the hydrofluorothioether from the coating; and A method comprising:

7. The following structural formula (I): Rf-S-Rh (I) wherein Rf is a perfluorinated group having 2 to 9 carbon atoms, and Rh is a non-fluorinated hydrocarbon group having 1 to 3 carbon atoms. and a hydrofluorothioether represented by a perfluoropolyether or silicone lubricant that is soluble or dispersible in the hydrofluorothioether; and A lubricant composition comprising:

8. based on the total weight of the lubricant composition (a) 0.001% to 10% by weight of a perfluoropolyether lubricant; (b) 90% to about 99.999% by weight of said hydrofluorothioether; The lubricant composition of claim 7, comprising:

9. 1. A method of lubricating a substrate, comprising: (a) applying a coating of the lubricant composition of claim 7 or 8 to a substrate; (b) removing the hydrofluorothioether from the coating; and A method comprising:

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