US3833507A - Azeotropic composition - Google Patents
Azeotropic composition Download PDFInfo
- Publication number
- US3833507A US3833507A US00255972A US25597272A US3833507A US 3833507 A US3833507 A US 3833507A US 00255972 A US00255972 A US 00255972A US 25597272 A US25597272 A US 25597272A US 3833507 A US3833507 A US 3833507A
- Authority
- US
- United States
- Prior art keywords
- solvent
- azeotropic composition
- cleaning
- tetrachloro
- vapor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G5/00—Cleaning or de-greasing metallic material by other methods; Apparatus for cleaning or de-greasing metallic material with organic solvents
- C23G5/02—Cleaning or de-greasing metallic material by other methods; Apparatus for cleaning or de-greasing metallic material with organic solvents using organic solvents
- C23G5/028—Cleaning or de-greasing metallic material by other methods; Apparatus for cleaning or de-greasing metallic material with organic solvents using organic solvents containing halogenated hydrocarbons
- C23G5/02809—Cleaning or de-greasing metallic material by other methods; Apparatus for cleaning or de-greasing metallic material with organic solvents using organic solvents containing halogenated hydrocarbons containing chlorine and fluorine
- C23G5/02812—Perhalogenated hydrocarbons
- C23G5/02816—Ethanes
- C23G5/02822—C2Cl4F2
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D7/00—Compositions of detergents based essentially on non-surface-active compounds
- C11D7/50—Solvents
- C11D7/5036—Azeotropic mixtures containing halogenated solvents
- C11D7/5068—Mixtures of halogenated and non-halogenated solvents
- C11D7/5077—Mixtures of only oxygen-containing solvents
- C11D7/5081—Mixtures of only oxygen-containing solvents the oxygen-containing solvents being alcohols only
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G5/00—Cleaning or de-greasing metallic material by other methods; Apparatus for cleaning or de-greasing metallic material with organic solvents
- C23G5/02—Cleaning or de-greasing metallic material by other methods; Apparatus for cleaning or de-greasing metallic material with organic solvents using organic solvents
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G5/00—Cleaning or de-greasing metallic material by other methods; Apparatus for cleaning or de-greasing metallic material with organic solvents
- C23G5/02—Cleaning or de-greasing metallic material by other methods; Apparatus for cleaning or de-greasing metallic material with organic solvents using organic solvents
- C23G5/028—Cleaning or de-greasing metallic material by other methods; Apparatus for cleaning or de-greasing metallic material with organic solvents using organic solvents containing halogenated hydrocarbons
- C23G5/02806—Cleaning or de-greasing metallic material by other methods; Apparatus for cleaning or de-greasing metallic material with organic solvents using organic solvents containing halogenated hydrocarbons containing only chlorine as halogen atom
Definitions
- This invention relates to an azeotropic composition of a tetrachlorodifiuoroethane, methanol and trichloroethylene.
- chlorofluoroethanes have attained widespread use as specialty solvents in recent years, particularly tetrachlorodifiuoroethane.
- This is a relatively high melting compound (CCI FCCl F, 24.5 C.), which is nontoxic and nonflammable, and which has satisfactory solvent power for greases, oils, waxes and the like under certain conditions. It has therefore found use in cleaning electric motors, compressors, lithographic plates, typewriters, instruments, gauges, and as noncorrosive brines.
- Printed circuits are well known in the electronics art; and consist of a circuit formed from a soft metal on a solid, non-conducting surface such as a reinforced phenolic resin. During manufacture, the solid surface is coated with the metal, the desired portion of metal is coated with an impervious coating, and the excess metal is removed by etching with a suitable acid. After the excess metal has been removed, it is necessary to remove the impervious coating because solder joints must be made to the printed circuit and these will not form if the coating is present. After the impervious coating is removed, the circuits are coated with a rosin flux to permit the joints to be soldered, after which the rosin flux must then be removed.
- the chlorofluoroethane solvent does not have sufiicient solvent power to clean printed circuits; that is, to effectively remove the rosin flux.
- mixtures of solvents may be used for this purpose they have the disadvantage that they boil over a range of temperatures and consequently undergo fractionation in vapor degreasing or ultrasonic applications which are open to the atmosphere.
- the solvent When employing either of these cleaning or degreasing methods the solvent must also be both relatively nontoxic and nonflammable for safety reasons.
- Tetrachlorodifluoroethane is a relatively high boiling fluorocarbon and for this reason is especially advantageous in vapor degreasing applications since at these temperatures the hot vapor has more of a tendency to dissolve high melting greases, or fluxes as Well as oil residues and the like.
- the solvent vapors tend to condense on the article until the articles are heated by the vapors from room temperature up to the temperature of the vapor.
- the condensation thus formed on the articles tends to drip back into the solvent reservoir taking 3,833,507 Patented Sept. 3, 1974 with it some of the soil on the article. For this reason the ability of a cleaning solvent to condense on the surface is especially advantageous.
- Tetrachlorodifluoroethane also is a better solvent than materials such as trichlorotrifluoromethane, however, it suffers the disadvantage that it is solidus at room temperature whereas the latter is liquidus. Accordingly tetrachlorodifluoroethane is more difiicult to handle than liquid type cleaning solvents.
- the above object of this invention may be accomplished by a novel ternary azeotropic composition of tetrachlorodifiuoroethane (e.g. 1,1,2,2-tetrachloro 1,2 difluoroethane), methanol and trichloroethylene.
- 1,1,2,2-tetrachloro 1,2 difluoroethane is the preferred tetrachlorodifluoroethane
- the isomer 1,1,1,2 tetrachloro-2,2-difluoroethane may be substituted therefor in whole or in part and especially in minor amounts or trace amounts.
- the ternary azeotrope of this invention is unusual but not unique among ternary azeotropes in that the proportions of the three elements of the azeotrope can vary to appreciable extent.
- the permissible variations in the azeotrope, Without an appreciable change in boiling point are as follows:
- compositions Percent by weight 1,1,2,2 tetrachloro 1,2 difiuoroethane 34-41 Methanol 30 Trichloroethylene 36-29 These mixtures form azeotropes which distill at a constant temperature, the liquid phase and the vapor phase in equilibrium therewith having the same composition. Such mixture is relatively nonfiammable and nontoxic in both the liquid phase and the vapor phase. These mixtures are particularly useful as solvents for greases, oils, waxes, and the like and cleaning electric motors, compressors, lithographic plates, typewriters, precision instruments, gauges, and the like and are particularly useful for cleaning printed circuits.
- the azeotropic mixtures are obtained at approximately 760 mm. Hg a variation in pressure and consequently a change in the compositions and boiling points are also intended to be 'within the broad scope of the invention.
- the azeotropes may contain many ditferent proportions of all of the aforementioned components provided a constant boiling mixture is obtained at the various pressures at which the compositions are used. Stated otherwise any pressure may be employed to obtain the azeotropes of this invention as long as a three component or two component constant boiling mixture is obtained, and accordingly the ratio of components of the azeotropes of the invention will also vary.
- the present invention relates to the aforementioned azeotropes that boil at atmospheric pressure i about 25, especially 1 about 15 mm. Hg.
- Example II Repeating the procedure of Example I, beginning with a mixture of equal amounts of each of the three components an azeotropic mixture which has a constant boiling point of 140 F. at 760 mm. Hg consisting essentially of 34.3 percent l,1,2,2-tetrachloro-1,2-difluoroethane, 30.1 percent methanol and 35.6 percent trichloroethylene by weight.
- Printed circuit boards are usually prepared by impregnating glass cloth, nylon, or paper laminates with a phenolformaldehyde resin or an epoxy resin.
- Printed circuits are prepared by a variety of methods. In a typical procedure, the board consists originally of a phenolic resin impregnated base to which is bonded a sheet of copper, 2 to 4 mils thick, covering one surface of the board. The desired circuit is drawn on the copper with an asphalt based ink using the silk screen method. The excess copper is then removed by etching with a ferric chloride-hydrochloric acid bath, sometimes containing ammonium chloride, leaving on the board the copper that is covered by the ink.
- the asphalt ink is removed by cleaning with the azeotropic composition of this invention in an ultrasonic bath (some mechanical scrubbing is often used).
- the entire surface of the board is coated with a rosin flux and dried.
- the electronic components (resistors, capacitors, etc.) are then added at the proper places for soldering to the circuit.
- the board is then passed over a molten solder bath, contacting the desired joints with the molten metal, whereby the soldering is effected. After cooling, the excess rosin flux remaining on the board must be removed since, if present in the final assembly, it will lead to corrosion, poor electrical resistance and other deleterious properties.
- the board is cleaned by placing it in an ultrasonic bath of any of the aforementioned azeotropes and operating at about 32 kilocycles per second at about 10-20 F. below the boiling point of the particular azeotrope for about one minute.
- An azeotropic composition consisting essentially of from about 34 to 41 parts by weight of l,1,2,2-tetrachloro- 1,2-difluoroethane, about 30 parts methanol and from about 36 to 29 parts trichloroethylene.
- An azeotropic composition consisting essentially of about 34 parts by Weight of 1,1,2,2-tetrachloro-1,2-difluoroethane, about 30 parts methanol and about 36 parts trichloroethylene.
- An azeotropic composition consisting essentially of about 40 parts by weight of 1,1,2,2-tetrachloro-1,2-difiuoroethane, about 30 parts methanol and about 30 parts trichloroethylene.
- a method for cleaning a solid surface comprising contacting said surface with the composition of claim 1.
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Metallurgy (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Wood Science & Technology (AREA)
- Detergent Compositions (AREA)
- Manufacturing Of Printed Wiring (AREA)
Abstract
Description
Priority Applications (9)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US677715D USB677715I5 (en) | 1967-10-24 | ||
US677715A US3554918A (en) | 1967-10-24 | 1967-10-24 | Azeotropic composition |
CA027,298A CA955820A (en) | 1967-10-24 | 1968-08-13 | Azeotropic composition |
US54085A US3671446A (en) | 1967-10-24 | 1970-06-02 | Azeotropic composition |
US54081A US3671442A (en) | 1967-10-24 | 1970-06-02 | Azeotropic composition |
US54086A US3671445A (en) | 1967-10-24 | 1970-06-02 | Azeotropic composition |
US54084A US3671444A (en) | 1967-10-24 | 1970-06-02 | Azeotropic composition |
US54082A US3671443A (en) | 1967-10-24 | 1970-06-02 | Azeotropic composition |
US00255972A US3833507A (en) | 1967-10-24 | 1972-05-23 | Azeotropic composition |
Applications Claiming Priority (8)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US67771567A | 1967-10-24 | 1967-10-24 | |
US5408470A | 1970-06-02 | 1970-06-02 | |
US5408370A | 1970-06-02 | 1970-06-02 | |
US5408570A | 1970-06-02 | 1970-06-02 | |
US5408670A | 1970-06-02 | 1970-06-02 | |
US5408270A | 1970-06-02 | 1970-06-02 | |
US5408170A | 1970-06-02 | 1970-06-02 | |
US00255972A US3833507A (en) | 1967-10-24 | 1972-05-23 | Azeotropic composition |
Publications (1)
Publication Number | Publication Date |
---|---|
US3833507A true US3833507A (en) | 1974-09-03 |
Family
ID=27574375
Family Applications (8)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US677715D Pending USB677715I5 (en) | 1967-10-24 | ||
US677715A Expired - Lifetime US3554918A (en) | 1967-10-24 | 1967-10-24 | Azeotropic composition |
US54084A Expired - Lifetime US3671444A (en) | 1967-10-24 | 1970-06-02 | Azeotropic composition |
US54085A Expired - Lifetime US3671446A (en) | 1967-10-24 | 1970-06-02 | Azeotropic composition |
US54081A Expired - Lifetime US3671442A (en) | 1967-10-24 | 1970-06-02 | Azeotropic composition |
US54082A Expired - Lifetime US3671443A (en) | 1967-10-24 | 1970-06-02 | Azeotropic composition |
US54086A Expired - Lifetime US3671445A (en) | 1967-10-24 | 1970-06-02 | Azeotropic composition |
US00255972A Expired - Lifetime US3833507A (en) | 1967-10-24 | 1972-05-23 | Azeotropic composition |
Family Applications Before (7)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US677715D Pending USB677715I5 (en) | 1967-10-24 | ||
US677715A Expired - Lifetime US3554918A (en) | 1967-10-24 | 1967-10-24 | Azeotropic composition |
US54084A Expired - Lifetime US3671444A (en) | 1967-10-24 | 1970-06-02 | Azeotropic composition |
US54085A Expired - Lifetime US3671446A (en) | 1967-10-24 | 1970-06-02 | Azeotropic composition |
US54081A Expired - Lifetime US3671442A (en) | 1967-10-24 | 1970-06-02 | Azeotropic composition |
US54082A Expired - Lifetime US3671443A (en) | 1967-10-24 | 1970-06-02 | Azeotropic composition |
US54086A Expired - Lifetime US3671445A (en) | 1967-10-24 | 1970-06-02 | Azeotropic composition |
Country Status (2)
Country | Link |
---|---|
US (8) | US3554918A (en) |
CA (1) | CA955820A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0105427A1 (en) * | 1982-09-27 | 1984-04-18 | Daikin Kogyo Co., Ltd. | Use of a composition of 1,1,2,2-tetrachloro-1,2-difluoroethane, 1,1,2-trichloro-1,2,2-trifluoroethane and at least one other organic solvent for cleaning purposes |
US4659505A (en) * | 1985-02-20 | 1987-04-21 | Daikin Kogyo Co., Ltd. | Azeotropic like composition |
US4906304A (en) * | 1987-01-28 | 1990-03-06 | Kali-Chemie Aktiengesellschaft | Difluorotetrachloroethane mixtures and their use in removing waxes |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3936387A (en) * | 1972-02-04 | 1976-02-03 | Phillips Petroleum Company | Azeotrope of 1,2-dichloro-1-fluoroethane and methanol |
US4023984A (en) * | 1973-02-02 | 1977-05-17 | Imperial Chemical Industries Limited | Azeotropic solvent composition for cleaning |
US3957530A (en) * | 1973-03-06 | 1976-05-18 | Phillips Petroleum Company | Ternary azeotropic paint stripping compositions |
US3904542A (en) * | 1973-03-06 | 1975-09-09 | Phillips Petroleum Co | Azeotropic composition of fluorocarbon |
US4035258A (en) * | 1973-08-27 | 1977-07-12 | Phillips Petroleum Company | Azeotropic compositions |
US4169807A (en) * | 1978-03-20 | 1979-10-02 | Rca Corporation | Novel solvent drying agent |
NO834067L (en) * | 1982-11-08 | 1984-05-09 | Dow Chemical Co | SOLVENT MIXTURE TO REMOVE FLUID |
US4524011A (en) * | 1982-11-08 | 1985-06-18 | The Dow Chemical Company | Flux removal solvent blend |
US5514221A (en) * | 1993-04-15 | 1996-05-07 | Elf Atochem North America, Inc. | Cold cleaning process |
US5552080A (en) * | 1993-04-15 | 1996-09-03 | Elf Atochem North America, Inc. | Cold cleaning solvents |
US6342471B1 (en) * | 2000-01-25 | 2002-01-29 | Toney M. Jackson | Electrical contact cleaner |
FR2855069B1 (en) * | 2003-05-22 | 2006-06-16 | Solvay | PROCESS FOR THE SEPARATION OF AT LEAST ONE ORGANIC COMPOUND |
-
0
- US US677715D patent/USB677715I5/en active Pending
-
1967
- 1967-10-24 US US677715A patent/US3554918A/en not_active Expired - Lifetime
-
1968
- 1968-08-13 CA CA027,298A patent/CA955820A/en not_active Expired
-
1970
- 1970-06-02 US US54084A patent/US3671444A/en not_active Expired - Lifetime
- 1970-06-02 US US54085A patent/US3671446A/en not_active Expired - Lifetime
- 1970-06-02 US US54081A patent/US3671442A/en not_active Expired - Lifetime
- 1970-06-02 US US54082A patent/US3671443A/en not_active Expired - Lifetime
- 1970-06-02 US US54086A patent/US3671445A/en not_active Expired - Lifetime
-
1972
- 1972-05-23 US US00255972A patent/US3833507A/en not_active Expired - Lifetime
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0105427A1 (en) * | 1982-09-27 | 1984-04-18 | Daikin Kogyo Co., Ltd. | Use of a composition of 1,1,2,2-tetrachloro-1,2-difluoroethane, 1,1,2-trichloro-1,2,2-trifluoroethane and at least one other organic solvent for cleaning purposes |
US4517108A (en) * | 1982-09-27 | 1985-05-14 | Daikin Kogyo Co., Ltd. | Cleaning composition |
US4659505A (en) * | 1985-02-20 | 1987-04-21 | Daikin Kogyo Co., Ltd. | Azeotropic like composition |
US4906304A (en) * | 1987-01-28 | 1990-03-06 | Kali-Chemie Aktiengesellschaft | Difluorotetrachloroethane mixtures and their use in removing waxes |
Also Published As
Publication number | Publication date |
---|---|
US3671444A (en) | 1972-06-20 |
US3671443A (en) | 1972-06-20 |
US3671445A (en) | 1972-06-20 |
US3671446A (en) | 1972-06-20 |
US3671442A (en) | 1972-06-20 |
US3554918A (en) | 1971-01-12 |
CA955820A (en) | 1974-10-08 |
USB677715I5 (en) |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: MORGAN GUARANTY TRUST COMPANY OF NEW YORK, AND MOR Free format text: MORTGAGE;ASSIGNORS:UNION CARBIDE CORPORATION, A CORP.,;STP CORPORATION, A CORP. OF DE.,;UNION CARBIDE AGRICULTURAL PRODUCTS CO., INC., A CORP. OF PA.,;AND OTHERS;REEL/FRAME:004547/0001 Effective date: 19860106 |
|
AS | Assignment |
Owner name: UNION CARBIDE CORPORATION, Free format text: RELEASED BY SECURED PARTY;ASSIGNOR:MORGAN BANK (DELAWARE) AS COLLATERAL AGENT;REEL/FRAME:004665/0131 Effective date: 19860925 |
|
AS | Assignment |
Owner name: ARCO CHEMICAL TECHNOLOGY, INC., 3 CHRISTINA CENTER Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:UNION CARBIDE CHEMICALS AND PLASTICS COMPANY, INC.;REEL/FRAME:005546/0106 Effective date: 19900911 |