CLEANING SOLVENT BLENDS OF LOW GLOBAL WARMING POTENTIAL EXHIBITING AZEOTROPE-LIKE BEHAVIOR AND THEIR USE

Abstract

Cleaning solvent compositions comprising, consisting essentially of, or consisting solely of, trans-dichloroethylene, 1-chloro-2,3,3-trifluoropropene and 1,1,2,2,3,3,4-heptafluorocyclopentane, and, optionally, one or both of surfactants and cosolvents, have utility as non-flammable, low-global warming potential, azeotrope-like cleaning fluids and carrier fluids for lubricants and the like. A method for cleaning articles of soiling substances comprises contacting the articles with the solvent composition by any suitable means such as a spray delivered by a propellant gas, or by contact with liquid and/or vapor solvent compositions, as in a conventional vapor degreaser apparatus, and removing the composition from the articles.

Claims

1. A solvent composition having azeotrope-like properties and consisting essentially of at least about 70 weight percent trans-dichloroethylene, at least about 1 weight percent 1,1,2,2,3,3,4-heptafluorocyclopentane, at least about 0.5 weight percent of 1-chloro-2,3,3-trifluoropropene, and, optionally, one or both of a surfactant and a cosolvent.

2. The composition of claim 1 wherein the trans-dichloroethylene is present in the amount of from about 70 to about 97 weight percent, 1,1,2,2,3,3,4-heptafluorocyclopentane is present in the amount of from about 1 to about 15 weight percent, and the 1-chloro-2,3,3-trifluoropropene is present in the amount of from about 0.5 to about 15 weight percent.

3. The composition of claim 1 or claim 2 wherein the cosolvent is present and is selected from the class consisting of one or more of (a) N,N dimethyl 9-decenamide trade name Steposol MET-10U (b) a mixture of about greater than 80 weight percent polyoxyethylene tridecyl ether phosphate, less than about 18 weight percent alcohol ethoxylate, less than about 1 weight percent phosphoric acid, and less than about 1 weight percent water (c) benzyl alcohol, and (d) hexylene glycol.

4. The composition of claim 1 or claim 2 wherein the surfactant, when present, is present in the amount of from about 0.1 to about 3 weight percent.

5. The composition of claim 4 wherein the cosolvent is present in an amount of about 1 to about 50 weight percent of the weight of the other ingredients of the composition.

6. The composition of claim 1 or claim 2 containing from about 70 to about 95.7 weight percent trans-dichloroethylene, from about 15 to about 3.8 weight percent heptafluorocyclopentane, and from about 15 to about 0.5 weight percent 1-chloro-2,3,3-trifluoropropene.

7. The composition of claim 1 or claim 2 containing from about 88 to about 94.2 weight percent trans-dichloroethylene, from about 6 to about 3.8 weight percent heptafluorocyclopentane, and from about 6 to about 2 weight percent 1-chloro-2,3,3-trifluoropropene.

8. The composition of claim 1 or claim 2 containing from about 91 to about 92.7 weight percent trans-dichloroethylene, from about 4.5 to about 3.8 weight percent heptafluorocyclopentane, and from about 4.5 to about 3.5 weight percent 1-chloro-2,3,3-trifluoropropene.

9. The composition of claim 1 or claim 2 containing from about 70 to about 95.5 weight percent trans-dichloroethylene, from about 15 to about 4 weight percent heptafluorocyclopentane, and from about 15 to about 0.5 weight percent 1-chloro-2,3,3-trifluoropropene.

10. The composition of claim 1 or claim 2 containing about 92 weight percent trans-dichloroethylene, about 4 weight percent heptafluorocyclopentane, and about 4 weight percent 1-chloro-2,3,3-trifluoropropene.

11. The composition of claim 1 or claim 2 containing from about 88 to about 92 weight percent trans-dichloroethylene, from about 6 to about 4 weight percent heptafluorocyclopentane, and from about 6 to about 4 weight percent 1-chloro-2,3,3-trifluoropropene.

12. The composition of claim 1 or claim 2 containing about 90 weight percent trans-dichloroethylene, about 5 weight percent heptafluorocyclopentane, and about 5 weight percent 1-chloro-2,3,3-trifluoropropene.

13. The composition of claim 1 or claim 2 wherein the 1-chloro-2,3,3-trifluoropropene is present in the amount of from about 2 to about 7 weight percent.

14. The composition of claim 1 wherein the trans-dichloroethylene is present in the amount of from about 80 to about 97 weight percent, 1,1,2,2,3,3,4-heptafluorocyclopentane is present in the amount of from about 1 to about 13 weight percent, and the 1-chloro-2,3,3-trifluoropropene is present in the amount of from about 2 to about 7 weight percent.

15. A method of cleaning an article of manufacture by contacting the article with the solvent composition of any one of claim 1 or claim 2 and then removing the solvent composition from the article.

16. The method of claim 15 wherein the contacting of the article with the solvent composition is carried out by vaporizing the composition and contacting the article with the resulting vapor, and after such contacting the vapor is condensed to liquid and drains from the article.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG. 1 is a schematic view in elevation of a bench top simulation of a standard 2-sump vapor degreaser comprising a dual bulb apparatus of the type used to develop the data illustrated in FIGS. 2 and 3;

[0022] FIG. 2 is a graph plotting the change in composition of a cleaning solvent embodiment of the present invention (Example 5) measured in the rinse sump of a vapor degreaser against the time period of repeated distillation and condensation; and

[0023] FIG. 3 is a graph identical to that of FIG. 2 except that the change in composition is measured in the boil sump of the vapor degreaser.

DETAILED DESCRIPTION OF THE INVENTION AND SPECIFIC EMBODIMENTS THEREOF

[0024] The following abbreviations, trademarks and trade names have the following meanings, whether used in the singular or plural form.

“TDCE”. Trans-Dichloroethylene. Chemical Abstracts Number (“CAS #”) 156-60-5.
“XF”. The hydrofluorocarbon, 2,3-dihydrodecafluoropentane (HFC-4310-mee) [Tradename Vertrel XF]. CAS #1384-95-42.
“AS-300”. A blend of cis- and trans-stereoisomers of 1-chloro-2,3,3-trifluoropropene composed of >89 wt (Z)-1-chloro-2,3,3-trifluoropropene and <10 wt % (E)-1-chloro-2,3,3-trifluoropropene, as supplied by AGC, Inc. Chemicals Company under the tradename “Amolea AS-300”.
“SF33”. The hydrofluoroolefin, (Z)-1,1,1,4,4,4-Hexafluoro-2-butene; Tradename Opteon SF33 by Chemours Company. CAS #692-49-9.
“HFX-110”. Methylperfluoroheptene ethers; Tradename HFX-110. CAS #Proprietary.
“HFCP”. 1,1,2,2,3,3,4-Heptafluorocyclopentane. Tradename Zeorora. CAS #15290-77-4.
“Vertrel® SFR”. A blend of 67 wt % trans-dichloroethylene, 18 wt % 2,3-dihydrodecafluoropentane (HFC-4310-mee); 12 wt % heptafluorocyclopentane; 3 wt % methanol. This material has a boiling point of 106° F. (41.1° C.) and is available from Chemours Corporation of Wilmington, Delaware.
“Opteon SF79”. A blend of nominally 95.2 wt % trans-dichloroethylene, 4.0 wt % methylperfluoroheptene ethers (HFX-110) and 0.8 wt % 2,3-dihydrodecafluoropentane (HFC 43-10mee). This material has a boiling point of 121° F. (49.4° C.) and is available from Chemours Corporation of Wilmington, Delaware.
“Opteon SF80”. A blend of nominally 95.2 wt % trans-dichloroethylene, 4.0 wt % methylperfluoroheptene ethers (HFX-110) and 0.8 wt % (Z)-1,1,1,4,4,4-Hexafluoro-2-butene (Opteon SF33). This material has a boiling point of 121° F. (49.4° C.) and is available from Chemours Corporation of Wilmington, Delaware.

“MeOH”. Methyl Alcohol.

[0025] FIG. 1 shows laboratory glassware 10 comprising a boil bulb 12 having a neck 12a which protrudes into rinse bulb 14. Neck 12a has formed therein an aperture 12b which is disposed within rinse bulb 14. A condenser 16 is fitted to rinse bulb 14 at the outlet end 14a thereof and comprises a cooling coil 18 disposed within condenser 16. A cold water inlet 18a is connected to a source of cooling water (not shown) and a cold water outlet 18b is connected to a water discharge (not shown). Boil bulb 12 is disposed upon a heating mantel 20.

[0026] In use, a solvent composition to be tested is introduced into boil bulb 12 and heated to boil the solvent composition and generate a vapor which rises to rinse bulb 14 and then into condenser 16 as indicated by arrows V 1. Vapor is condensed by contact with cooling coil 18 and flows into rinse bulb 14 as indicated by arrows C1. When the condensate collected in rinse bulb 14 reaches the level of aperture 12b, the overflow solvent flows back into boil bulb 12 as indicated by arrow C2.

[0027] Standard Test Procedure. Trials were conducted in standard 2-sump vapor degreasers or in bench top simulation using a “dual bulb” apparatus of the type illustrated in FIG. 1 having a standard solvent still head with collection flask and sampling port (not shown in FIG. 1) on the boil flask. Samples from various locations and times are analyzed by gas chromatography using an Agilent Corporation DB-200 capillary column (trifluoropropyl methyl dimethyl siloxane stationary phase) and an FID detector. The following examples report the results of trials conducted pursuant to this Standard Test Procedure.

Comparative Example 1. Distillation of Vertrel SFR in a Vapor Degreaser

[0028]

TABLE-US-00001 Composition of Vertrel SFR Over Time in Branson B-452R Degreaser wt % TDCE wt % HFCP wt % XF wt % MeOH Virgin (Drum) 67.7 12.2 17.3 2.8 Time Boil Rinse Boil Rinse Boil Rinse Boil Rinse Distilled Sump Sump Sump Sump Sump Sump Sump Sump 1 hour 75.8 68 16.5 12.2 6.6 16.7 0.9 2.9 2 hours 76.4 67.6 16.8 12.1 5.9 17.2 0.8 3 5 hours 77.3 68.3 16.4 11.7 5.4 16.9 0.7 3 7 hours 77.3 68.3 16.5 11.7 5.3 16.9 0.7 3 9 hours 76.9 67.9 16.9 12.1 5.4 16.9 0.7 2.9 12 hours 77.9 68.3 15.9 11.5 5.3 17.1 0.7 3 17 hours 78.2 68.7 15.6 11.1 5.3 17.1 0.7 3.1

[0029] It can be seen that this blend of solvents, although remaining substantially azeotrope-like in behavior, changes its vapor composition quickly and dramatically. The ratios partition between the boil and rinse sump with the TDCE levels changing by more than 10 wt % from the original values (67.7 weight % to 78.2 weight %).

Comparative Example 2. Distillation of Opteon SF79

[0030]

TABLE-US-00002 Composition of Opteon SF79 over time in a vapor degreaser wt % TDCE wt % HFX-110 wt % XF Virgin (Drum) 95.1 4.1 0.8 Time Boil Rinse Boil Rinse Boil Rinse Distilled Sump Sump Sump Sump Sump Sump 4.5 hours 95.64 95.05 4.23 4.03 0.13 0.92 13 hours 95.63 95.29 4.27 4.08 0.1 0.63 21.5 hours 95.61 95.28 4.24 4.1 0.15 0.62 29.5 hours 95.6 95.35 4.27 4.1 0.13 0.55 wt % +0.5 +0.3 +4.1 0 −83.7 −31.2 change

[0031] It can be seen that this product blend also changes ratio between the “boil” and “rinse” flasks. Most dramatically, the Vertrel XF which is present to improve the non-flammable characteristic of the blend, has been substantially depleted in the boil sump.

Comparative Example 3. Distillation of Opteon SF80

[0032]

TABLE-US-00003 Composition of Opteon SF80 over time in a vapor degreaser wt % TDCE wt % HFX-110 wt % SF33 Virgin (Drum) 95.04 4.1 0.87 Time Boil Rinse Boil Rinse Boil Rinse Distilled Sump Sump Sump Sump Sump Sump 1 hours 95.54 95.28 4.43 4.01 0.03 0.71 2 hours 95.54 95.15 4.40 4.03 0.03 0.82 3 hours 95.57 95.10 4.37 4.05 0.04 0.85 4 hours 95.60 95.15 4.36 4.05 0.03 0.80 wt % +0.6 +0.1 +6.3 −1.2 −96.6 −8.0 change

[0033] It can be seen that this product blend also changes ratio between the “boil” and “rinse” flasks. Most dramatically, the SF33 which is present to improve the non-flammable characteristic of the blend, has been substantially depleted in the boil sump.

Example 4. Distillation of Blend 18-63-1 in a Dual-Bulb Apparatus

[0034] Blend 18-63-1 is nominally a blend of 92 wt % trans-dichloroethylene, 4 wt % heptafluorocyclopentane and 4 wt % 1-chloro-2,3,3-trifluoropropene

TABLE-US-00004 Composition of 18-63-1 over time in a dual-bulb apparatus wt % TDCE wt % HFCP wt % AS-300 Virgin (Drum) 91.97 3.92 4.11 Time Boil Rinse Boil Rinse Boil Rinse Distilled Sump Sump Sump Sump Sump Sump 1 hours 95.41 90.13 2.12 4.91 2.47 4.95 2 hours 94.98 90.71 2.35 4.61 2.67 4.67 3 hours 94.71 91.02 2.49 4.45 2.80 4.53 4 hours 94.57 91.16 2.57 4.38 2.86 4.46 5 hours 94.65 91.41 2.53 4.20 2.82 4.39 6 hours 94.63 91.46 2.54 4.19 2.83 4.35 7 hours 94.77 91.52 2.47 4.16 2.76 4.32 8 hours 94.91 91.61 2.39 4.11 2.70 4.28 9 hours 95.00 91.69 2.35 4.05 2.65 4.26 10 hours 95.18 91.77 2.27 4.02 2.55 4.20 11 hours 94.65 91.82 2.54 4.00 2.81 4.18 wt % +2.9 −0.2 −35.2 +2.0 −31.6 +1.7 change

[0035] As shown by Example 4, this embodiment of the present invention redistributes ratios to a smaller degree than Opteon SF79 or Opteon SF80. The cleaning power and non-flammable behavior is maintained in all locations of the vapor degreaser.

Example 5. Distillation of Blend 18-70-1 in a Dual-Bulb Apparatus

[0036] Blend 18-70-1 is nominally a blend of 92 wt % trans-dichloroethylene, 5 wt % 1,1,2,2,3,3,4-heptafluorocyclopentane and 5 wt % 1-chloro-2,3,3-trifluoropropene. FIGS. 2 and 3 are graphs which plot the values of the following table, the rinse sump data being shown in FIG. 2 and the boil sump data being shown in FIG. 3. It is seen that in both FIGS. 2 and 3 the values for HFCP and AS-300 substantially overlie each other.

TABLE-US-00005 Composition of 18-70-1 over time in a dual-bulb apparatus wt % TDCE wt % HFCP wt % AS-300 Virgin (Drum) 89.94 5.05 5.01 Time Boil Rinse Boil Rinse Boil Rinse Distilled Sump Sump Sump Sump Sump Sump 1 hours 92.45 88.32 3.75 5.89 3.79 5.79 2 hours 91.99 88.69 3.99 5.69 4.02 5.61 3 hours 91.89 88.82 4.05 5.63 4.06 5.55 4 hours 91.79 88.83 4.09 5.65 4.12 5.52 5 hours 91.78 88.84 4.10 5.65 4.12 5.51 6 hours 91.86 88.81 4.06 5.66 4.08 5.53 7 hours 91.96 88.97 4.00 5.55 4.04 5.48 wt % +2.2 −1.1 −20.8 +9.9 −19.4 +9.4 change

[0037] Example 5 shows a smaller overall shift in composition of this embodiment of in the present invention as compared to composition 18-63-1 (Example 4) or Opteon SF79 (Comparative Example 2) or Opteon SF80 (Comparative Example 3). The blend of this Example 5, as is the case with the other embodiments of the present invention, redistributes and stabilizes the components to form consistent rinse and boil compositions.

Example 6

[0038] The composition of the solvent blend of this embodiment of the present invention stays nearly the same after 13 hours of distillation even with the addition of paraffin wax as a contaminant.

TABLE-US-00006 Composition of 18-70-1 over time in dual- bulb with contamination additions Hours wt % wt % wt % wt % Boiling distilled TDCE AS300 HFCP wax added Temp (C.) 0 89.88 5.05 5.07 0 45 1 88.33 5.78 5.89 0 45 2 88.66 5.62 5.72 1 45 3 88.68 5.59 5.72 2 45 4 88.69 5.58 5.73 3 45 5 88.76 5.58 5.65 4 45 6 88.76 5.59 5.66 5 45 7 88.42 5.72 5.86 5 45 8 88.57 5.65 5.78 6 45 9 88.67 5.59 5.74 7.6 45 10 88.71 5.58 5.71 9 45 11 88.78 5.58 5.64 11 45 12 88.88 5.52 5.6 12 45 13 88.85 5.52 5.63 15.5 45 wt % change −1.1 +9.3 +11.0 +15.5 0

[0039] Example 6 shows that the invention presents very little composition shift even when high concentrations of contamination are added to the boil sump. This example demonstrates that the azeotropic blend maintains stability during use.

Example 7

[0040] The embodiment of the present invention maintains good stability of the composition during fractional distillation.

TABLE-US-00007 Composition of 18-70-1 during fractional distillation Fraction wt % wt % wt % wt % Hours Distilled TDCE AS300 HFCP Solvent remaining Start 89.96 5.01 5.03 100 1 87.26 6.3 6.43 61.8 2 88.4 5.71 5.89 49.8 3 89.22 5.3 5.48 38.5 4 90.16 4.88 4.96 27.4 5 91.43 4.28 4.28 16.0 6 93.47 3.34 3.19 4.1 7 96.38 1.98 1.64 0.1

[0041] Example 7 shows that the present invention maintains azeotrope-like composition during fractional distillation. The composition exhibits little shift even when 84 wt % of the bulk solvent has evaporated.

Example 8

[0042] The present invention maintains non-flammability even after the compositions shifts during distillation.

TABLE-US-00008 Flammability of 18-70-1 distillation fractions by “pan test” Fraction wt % wt % wt % Hours Distilled TDCE AS300 HFCP Flammable? Start 89.96 5.01 5.03 Non-flammable 1 87.26 6.3 6.43 Non-flammable 2 88.4 5.71 5.89 Non-flammable 3 89.22 5.3 5.48 Non-flammable 4 90.16 4.88 4.96 Non-flammable 5 91.43 4.28 4.28 Non-flammable 6 93.47 3.34 3.19 Non-flammable 7 96.38 1.98 1.64 Non-flammable

[0043] The formulas listed in Example 8 were tested for potential flammability using the “pan test”. A metal pan was filled with 10 mL of solvent in a fume hood. A flame source was passed over the surface of the liquid and the flame was monitored for size and duration. Once the flame extinguished, the fumes were allowed to dissipate for 30 seconds. The flame source was then passed over the solvent surface again. This process was repeated until all of the solvent had evaporated. The testing was ceased if the flames did not self-extinguish within 10 seconds. A solvent which self-extinguished the flames in less than 5 seconds was deemed “non-flammable.” A solvent which did not extinguish the flames after 5 seconds was deemed “flammable.” This test method is an internal specification to gauge flammability potential for solvent blends before testing via closed-cup or open-cup methods. Example 8 demonstrates that the distillation fractions of 18-70-1 are likely to be non-flammable.

Example 9

[0044] Efficacious embodiments of the present invention include the following solvent blends, each of which shows good cleaning properties, non-flammability, low global warming potential, and azeotrope-like properties. Each of the following solvent blends optionally may include one or both of a suitable surfactant and cosolvent in amounts which do not adversely affect the above noted desirable properties. [0045] A. A solvent blend exhibiting azeotrope-like properties containing: [0046] from about 70 to about 95.7 weight percent trans-dichloroethylene; [0047] from about 15 to about 3.8 weight percent heptafluorocyclopentane; and [0048] from about 15 to about 0.5 weight percent 1-chloro-2,3,3-trifluoropropene. [0049] B. A solvent blend of exhibiting azeotrope-like properties containing: [0050] from about 88 to about 94.2 weight percent trans-dichloroethylene; [0051] from about 6 to about 3.8 weight percent heptafluorocyclopentane; and [0052] from about 6 to about 2 weight percent 1-chloro-2,3,3-trifluoropropene. [0053] C. A solvent blend exhibiting azeotrope-like properties containing: [0054] from about 91 to about 92.7 weight percent trans-dichloroethylene; [0055] from about 4.5 to about 3.8 weight percent heptafluorocyclopentane; and [0056] from about 4.5 to about 3.5 weight percent 1-chloro-2,3,3-trifluoropropene. [0057] D. A solvent blend-exhibiting azeotrope-like properties containing: [0058] from about 70 to about 95.5 weight percent trans-dichloroethylene; [0059] from about 15 to about 4 weight percent heptafluorocyclopentane; and [0060] from about 15 to about 0.5 weight percent 1-chloro-2,3,3-trifluoropropene. [0061] E. A solvent blend exhibiting azeotrope-like properties containing: [0062] about 92 weight percent trans-dichloroethylene; [0063] about 4 weight percent heptafluorocyclopentane; and [0064] about 4 weight percent 1-chloro-2,3,3-trifluoropropene. [0065] F. A solvent blend exhibiting azeotrope-like properties containing: [0066] from about 88 to about 92 weight percent trans-dichloroethylene; [0067] from about 6 to about 4 weight percent heptafluorocyclopentane; and [0068] from about 6 to about 4 weight percent 1-chloro-2,3,3-trifluoropropene. [0069] G. A solvent blend exhibiting azeotrope-like properties containing: [0070] about 90 weight percent trans-dichloroethylene; [0071] about 5 weight percent heptafluorocyclopentane; and [0072] about 5 weight percent 1-chloro-2,3,3-trifluoropropene.

Example 10

[0073] A. The solvent blend of any one of Examples 9A-9G further containing at least one surfactant in an amount of 0.1 to about 3 weight percent. [0074] B. The solvent blend of any one of Examples 9A-9G further containing at least one cosolvent in an amount of 1 to about 50 weight percent.

Example 11

[0075] The following are methods of cleaning soiled articles which methods are exemplary of the present invention. [0076] A. A method for cleaning soiling substances from metal, ceramic and synthetic polymer articles comprises contacting one or more of the articles with a solvent composition having azeotrope-like properties, the composition containing: [0077] from about 70 to about 95.7 weight percent trans-dichloroethylene; [0078] from about 15 to about 3.8 weight percent heptafluorocyclopentane; [0079] from about 15 to about 0.5 weight percent 1-chloro-2,3,3-trifluoropropene; and [0080] removing the composition from the one or more articles. [0081] B. A method identical to that of Example 11A except that the solvent composition contains: [0082] from about 88 to about 94.2 weight percent trans-dichloroethylene; [0083] from about 6 to about 3.8 weight percent heptafluorocyclopentane; and [0084] from about 6 to about 2 weight percent 1-chloro-2,3,3-trifluoropropene. [0085] C. A method identical to that of Example 11A except that the solvent composition contains: [0086] from about 91 to about 92.7 weight percent trans-dichloroethylene; [0087] from about 4.5 to about 3.8 weight percent heptafluorocyclopentane; and [0088] from about 4.5 to about 3.5 weight percent 1-chloro-2,3,3-trifluoropropene. [0089] D. A method identical to that of Example 11A except that the solvent composition contains: [0090] about 90 weight percent trans-dichloroethylene; [0091] about 5 weight percent heptafluorocyclopentane; and [0092] about 5 weight percent 1-chloro-2,3,3-trifluoropropene. [0093] E. A method identical to that of Example 11A except that the solvent composition contains: [0094] from about 88 to about 92 weight percent trans-dichloroethylene; [0095] from about 6 to about 4 weight percent heptafluorocyclopentane; and [0096] from about 6 to about 4 weight percent 1-chloro-2,3,3-trifluoropropene.

[0097] While the invention has been described in detail with reference to specific embodiments of the invention, these embodiments are exemplary and not limiting.