Abstract: Azeotrope-like compositions of 1,1,1-trifluorohexane and perfluoromethylcyclohexane which are useful in a variety of industrial cleaning applications including defluxing of printed circuit boards.

Abstract: The system comprises a cleaning fluid circuit including at least one sealable cleaning vessel, which is adapted to hold a vacuum and contains a carrier for carrying stock to be cleaned and dried. The cleaning vessel is adapted to be hermetically sealed from the atmosphere and from the cleaning fluid circuit is adapted to be directly connected to the suction port of an ejector so that each batch of stock can be cleaned and can subsequently be dried more quicly and to a higher degree by the application of a desired vacuum. Even if the cleaning fluid consists of an organic solvent, the pollution of the premises and of the environment by solvent vapors will be minimized.

Abstract: Method for the production of ultrapure sulfuric acid including distillation of sulfuric acid material for the removal of soluble impurities and insoluble and non-volatile particles of 10 microns to 0.2 micron or less in size. Reprocessing is also provided. Distillation takes place in a distillation chamber having walls which are provided with means within the chamber to provide smooth convective upward flow of distilling liquid and vapor proximate the walls and means for smooth convective downward flow substantially centrally of the distillation chamber. Redirection means and packing together with reflux means insure the washing of rising vapor and direct the condensing vapor substantially centrally of the distillation chamber. Ultrapure sulfuric acid is also provided having 5 or less particles per cubic centimeter of a size of 0.5 micron and larger and less than 10 ppb of any specific trace impurity such as cations.

Abstract: For replacing cleaning compositions based on 1,1,2-trichloro-1,2,2-trifluoroethane (F113), the invention provides a composition comprising 55 to 79.5% by weight of 1,1-dichloro-1-fluoroethane (F141b), 20 to 40% by weight of methyl formate and 0.5 to 5% of methanol. These three compounds form a positive azeotrope (b.p.=28.3.degree. C. at atmospheric pressure).The composition, which may be stabilized, can be used for cleaning solid surfaces, in particular for removing flux from printed circuits and for degreasing mechanical parts.

Abstract: Azeotrope-like compositions comprising 1,1-dichloro-1-fluoroethane, dichlorotrifluoroethane, nitromethane and ethanol or methanol are stable and have utility as degreasing agents and as solvents in a variety of industrial cleaning applications including cold cleaning and defluxing of printed circuit boards.

Abstract: An improved stereolithographic apparatus and method is described. In one embodiment, the improvement includes immersing at least a portion of a part in a volume of a liquid solvent in a vapor degreaser while subjecting the portion to ultrasonic agitation to substantially remove excess resin. Several examples of solvents are provided, including ethanol, and Freon TMS. In a second embodiment, the improvement includes building the part on a layer of liquid resin supported by a volume of a dense, immiscible, and UV transparent intermediate liquid, and integratably immersing at least a portion of the built part in the intermediate liquid, and then either subjecting the immersed portion to ultrasonic agitation to substantially remove excess resin, or subjecting the immersed portion to UV light. Several examples of intermediate liquids are provided, including perfluorinated fluids, such as Fluorinert FC-40, and water-based salt solutions, such as solutions of magnesium sulfate or sodium chloride in water.

Abstract: Azeotrope-like compositions comprising 1,1,-dichloro-1-fluoroethane, dichlorotrifluoroethane, 1,2-dichloroethylene, and optionally ethanol or methanol are stable and have utility as degreasing agents and as solvents in a variety of industrial cleaning applications including cold cleaning and defluxing of printed circuit boards.

Abstract: Compositions suitable for use in cleaning processes formed of hydrogen-containing fluorochlorohydrocarbons selected from the group of consisting of tetrachloromonofluoroethanes, trichlorodifluoroethanes, dichlorotrifluoroethanes, dichloromonofluoroethanes and dichloropentafluoropropanes or a mixture one or more of these hydrogen-containing fluorochlorohydrocarbons in admixture with partially fluorinated alkanols containing two to four carbon atoms.

Abstract: Stable azeotrope-like compositions comprising 1,1-dichloro-1-fluoroethane, dichloroethylene, and optionally an alkanol which are useful in a variety of industrial cleaning applications including defluxing and some of which are also useful as blowing agents in the preparation of polyurethane foams.

Abstract: A radioactive decontamination method for decontaminating a radioactive-contaminated object by using methylene chloride in place of conventionally used hydrocarbon fluoride or perchloroethylene. The radioactive-contaminated object is impacted by methylene chloride solution. Before the impacting, a preparatory step is executed as required in which radioactive contaminant, which is usually radioactive-contaminated epoxy-resin paint layer on a part used in a nuclear facility, is impregnated with methylene chloride solution so as to swell, thus facilitating exfoliation of the contaminant from the object. The methylene chloride solution is filtered and distilled so as to be decontaminated and subjected to a repeated use for impacting the radioactive-contaminated object.

Abstract: Stable azeotrope-like compositions consisting essentially of dichloropentafluoropropane and an alkanol having 1-4 carbon atoms which are useful in a variety of industrial cleaning applications including cold cleaning and defluxing of printed circuit boards.

Abstract: Azeotrope-like compositions comprising 1,1-dichloro-1-fluoroethane; dichlorotrifluoroethane; methanol; and alkane having 5 or 6 carbon atoms are stable and have utility as degreasing agents and as solvents in a variety of industrial cleaning applications including cold cleaning and defluxing of printed circuit boards and dry cleaning.

Abstract: Azeotrope-like compositions comprising 1,1-dichloro-1-fluoroethane; dichlorotrifluoroethane; ethanol; and alkane having 5 or 6 carbon atoms are stable and have utility as degreasing agents and as solvents in a variety of industrial cleaning applications including cold cleaning and defluxing of printed circuit boards and dry cleaning.

Abstract: Azeotrope-like compositions comprising 1,1-dichloro-1-fluoroethane; dichlorotrifluoroethane; ethanol; and alkene having 5 carbon atoms are stable and have utility as degreasing agents and as solvents in a variety of industrial cleaning applications including cold cleaning and defluxing of printed circuit boards and dry cleaning.

Abstract: Azeotropic and azeotrope-like compositions composed of dichloropentafluoropropanes and acetone are described which are suitable for use in cleaning processes and in printing and copying processes for fixing toner based on polystyrene.

Abstract: Azeotrope-like compositions comprising 1,1-dichloro-1-fluoroethane; dichlorotrifluoroethane; methanol; and alkene having 5 carbon atoms are stable and have utility as degreasing agents and as solvents in a variety of industrial cleaning applications including cold cleaning and defluxing of printed circuit boards and dry cleaning.

Abstract: Novel azeotrope-like compositions comprising dichloropentafluoropropane, ethanol and a hydrocarbon containing six carbon atoms which are useful in a variety of industrial cleaning applications including cold cleaning and defluxing of printed circuit boards.

Abstract: Stable azeotrope-like compositions consisting essentially of dichloropentafluoropropane and a hydrocarbon containing six carbon atoms which are useful in a variety of industrial cleaning applications including cold cleaning and defluxing of printed circuit boards.

Abstract: Azeotrope-like compositions comprising dichloropentafluoropropane and 1,2-dichloroethylene are stable and have utility as degreasing agents and as solvents in a variety of industrial cleaning applications including cold cleaning and defluxing of printed circuit boards.

Abstract: Azeotropic mixtures of dichloropentafluoropropane (HCFC-225) and trans-1,2-dichloroethylene (T-HCC-1130) with methanol or ethanol or isopropanol, are useful in solvent cleaning applications as refrigerants, aerosol propellants and polymer blowing agents.

Abstract: Improved cleaning compositions are disclosed based on fluorochlorohydrocarbons, alkanols and at least one ester selected from the group consisting of methyl propionate, ethyl propionate and ethyl acetate. The compositions may optionally contain additional additives and are highly suitable for industrial cleaning processes or for vapor degreasing, for example, particularly for removing resin soldering fluxes containing high amounts of activator.

Abstract: A method of stabilizing chlorofluorocarbon compositions thereby is provided. The stabilized composition comprises a chlorofluorocarbon and a sufficient amount of an epoxidized, generally high molecular weight stabilizer having an oxirane content sufficient to effectively stabilize the chlorofluorocarbon. The stabilizer is preferably an epoxidized oil having a molecular weight in the range of about 300 to about 1,500 and an oxirane content of at least about 4%. The method includes the step of adding a sufficient amount of such a stabilizer to the chloroflurocarbon composition. The chlorofluorocarbon composition typically comprises chlorofluoromethane, chlorofluoroethane, mixtures thereof or a chlorofluorocarbon-alcohol azeotropic solution. Also provided is an improved continuous dialyzer cleaning method utilizing the stabilized chlorofluorocarbon composition.

Abstract: A method for maintaining a flammable solvent in a nonflammable environment involves covering the flammable solvent with a nonflammable vapor blanket provided by a nonflammable solvent, such that vapors from the flammable and nonflammable solvents form a nonflammable gaseous mixture in the blanket. Such a method is used in removal of both oil-based and polar contaminants to control the flammability potential of an alcohol solvent. An apparatus for cleaning articles using fluorocarbon and alcohol solvents includes a chamber having a plurality of compartments for containing the solvents and a bounded vapor space. At least one of the compartments contains liquid fluorocarbon and at least one other will contain liquid alcohol. The solvents voltalize into the bounded vapor space to provide a nonflammable vapor blanket over the alcohol-containing compartment.

Abstract: Novel azeotrope-like compositions comprising dichloropentafluoropropane, methanol, and a hydrocarbon containing six carbon atoms which are useful in a variety of industrial cleaning applications including cold cleaning and defluxing of printed circuit boards.

Abstract: Novel azeotrope-like compositions comprising dichloropentafluoropropane, 2-propanol and a hydrocarbon containing six carbon atoms which are useful in a variety of industrial cleaning applications including cold cleaning and defluxing of printed circuit boards.

Abstract: For replacing cleaning compositions based on 1,1,2-trichloro-1,2,2-trifluoroethane (F113), the invention provides a composition comprising 55 to 80% by weight of 1,1,1,2,2-pentalfuoro-3,3-dichloropropane (225ca) and 20 to 45% by weight of methyl tert-butyl ether.These two compounds form a negative azeotrope (b.p.=59.9.degree. C. at atmospheric pressure).The composition, which may be stabilized, can be used for cleaning solid surfaces, in particular for removing flux from printed circuits and for degreasing mechanical parts.

Abstract: An azeotropic mixture of polyfluoropentanes and methanol is disclosed. The azeotropic mixture is useful as: a cleaning agent, a blowing agent, a refrigerant, an aerosol propellant, a heat transfer medium and a power cycle working fluid.

Abstract: Azeotropic mixtures of 1,1,1,2,3,3-hexafluoro-3-methoxypropane with cis 1,2-dichloroethylene (c-CFC-1130) and methanol or ethanol or isopropanol or n-propanol, the azeotropic mixtures being useful in solvent cleaning applications.

Abstract: Azeotrope-like compositions of tertiary butyl 2,2,2-trifluoroethyl ether and perfluoromethylcyclohexane which are useful in a variety of industrial cleaning applications including defluxing of printed circuit boards.

Abstract: The invention relates to a novel azeotropic or azeotrope-like mixture which essentially comprises about 90-97% by mass of 2,2,2-trifluoroethyl 1,1,2,2-tetrafluoroethyl ether and about 3-10% by mass of ethanol and also to a process for cleaning electrical or electronic components, in particular soldered circuit boards or printed circuits, but also other solid surfaces, with the aid of said mixture. Soldering fluxes, in particular, can be removed from circuit boards with the aid of said mixture.

Abstract: Stable azeotrope-like compositions consisting essentially of 1,1-dichloro-1-fluoroethane, cyclopentane and optionally an alkanol which are useful in a variety of industrial cleaning applications including cold cleaning and defluxing of printed circuit boards.

Abstract: Stable azeotrope-like compositions of 1,1-dichloro-1-fluoroethane, a mono-chlorinated C.sub.3 alkane and optionally an alkanol which are useful in a variety of industrial cleaning applications including cold cleaning and defluxing of printed circuit boards.

Abstract: Stable azeotrope-like compositions comprising 1,1-dichloro-1-fluorethane, dichlorotrifluoroethane, ethanol, and a mono- or di-chlorinated C.sub.2 or C.sub.3 alkane which are useful in a variety of industrial cleaning applications.

Abstract: An apparatus for dissolving oil or PCB which exists in the electrical insulation of parts to be cleaned, wherein a solvent is evaporated during a heating phase by an evaporator located with the parts in an autoclave. The solvent vapor condenses on the parts and penetrates into the electrical insulation to form an oil or PCB-solvent mixture. The apparatus provides for a plurality of intermediate pressure reductions which are carried out in the autoclave, and during each intermediatre pressure reduction the solvent is simultaneously evaporated from the oil or PCB-solvent mixture, directly from the autoclave. That is, during each of the pressure reductions, the solvent supply is discontinued and the mixture circulated through a circulating line. Following the completion of each intermediate pressure reduction, the pure oil or PCB present in a condensate vessel is pumped out by an intermediately located feed pump through a connecting line and into a reservoir.

Abstract: Mixtures of the two fluorocarbon compounds 1,1,2,2,3,5,5,5-nonafluoro-4-trifluoromethylpentane and 1,1,1,2,2,5,5,5-octafluoro-4-trifluoromethylpentane with alcohols, ethers, esters, ketones, nitrogen-containing organic compounds, and halogenated hydrocarbons are disclosed; as is a process for cleaning a solid surface which comprises treating the surface with said mixtures. Ternary mixtures of about 88 to 96 weight percent total of said two fluorocarbon compounds with methanol (including at least about 11 weight percent 1,1,1,2,2,3,5,5,5-nonafluoro-4-trifluoromethylpentane and at least about 13 weight percent 1,1,1,2,2,5,5,5-octafluoro-4-trifluoromethylpentane) and with ethanol (including at least about 28 weight percent 1,1,1,2,2,3,5,5,5-nonafluoro-4-triluoformethylpentane and at least about 16 weight percent 1,1,1,2,2,5,5,5-octafluoro-4-trifluoromethyl-pentane) are disclosed as quasiazeotrope compositions that are useful where recovery and reuse of solvents is practiced.

Abstract: The invention relates to an azeotrope-type mixture which contains about 3-5% by weight of methanol and about 95-97% by weight of 1,4-dihydroperfluorobutane, and also to a process for cleaning electronic components, in particular soldered conductor boards or printed circuits, with the aid of said mixture.

Abstract: Mixtures of the compound 1,1,1,2,2,5,5,5-octafluoro-4-trifluoromethylpentane with alcohols, ethers, esters, ketones, nitrogen-containing organic compounds, and halogenated hydrocarbons are disclosed; as is a process for cleaning a solid surface which comprises treating the surface with said mixtures. Binary mixtures of 1,1,1,2,2,5,5,5-octafluoro-4-trifluoromethylpentane with about 5 to 13 weight percent methanol, with about 2 to 10 weight percent ethanol, with about 3 to 11 weight percent isopropanol, with about 50 to 58 weight percent dichloromethane, and with about 1 to 9 weight percent acetonitrile, are disclosed as azeotrope or azeotrope-like compositions and are particularly suited for use where solvent recovery and reuse is practiced.

Abstract: Mixtures of the compound 1,1,1,2,2,3,5,5,5-nonafluoro-4-trifluoromethylpentane with alcohols, ethers, esters, ketones, nitrogen-containing organic compounds, and halogenated hydrocarbons are disclosed; as is a process for cleaning a solid surface which comprises treating the surface with said mixtures. Binary mixtures of 1,1,1,2,2,3,5,5,5-nonafluoro-4-trifluoromethylpentane with about 5 to 13 weight percent methanol, with about 3 to 11 weight percent ethanol, with about 4 to 12 weight percent isopropanol, with about 52 to 60 weight percent trans-1,2-dichloroethylene, with about 47 to 55 weight percent dichloromethane, with about 1 to 9 weight percent trichloroethane, with about 0.1 to 7 weight percent acetonitrile, and with about 0.

Abstract: Azeotropic mixtures of 3-chloro-1,1,1-trifluoropropane (HCFC-253fb) with trans-1,2-dichloroethylene (t-HCC-1130) are useful in solvent cleaning applications.

Abstract: Azeotropic mixtures of 2,2-dichloro-1,2-difluoroethane (HCFC-132c) with methanol, ethanol, or trans-1,2-dichloroethylene (t-HCC-1130), the azeotropic mixtures being useful in solvent cleaning applications.

Abstract: Azeotropic mixtures of 1,1,1,2,3,4,4,5,5,5-decafluoropentane and methanol or ethanol or isopropanol, the azeotropic mixtures being useful in solvent cleaning applications, as blowing agents, refrigerants, heating mediums and aerosol propellants.

Abstract: Azeotropic mixtures of 1,1,1,2,3,4,4,5,5,5-decafluoropentane and trans 1,2-dichloroethylene with methanl or ethanol, the azeotropic mixtures being useful in solvent cleaning applications.

Abstract: Stable azeotrope-like compositions consisting essentially of 1,1,2-trichloro-1,2,2-trifluoroethane, 1,2-dichloroethylene, cyclopentane, methanol, nitromethane, and optionally diisopropylamine which are useful in a variety of industrial cleaning applications.

Abstract: A venetian blind or similar flexible flat article is held in tension on a foraminous belt and passed through washing, rinsing and drying zones. The condensate from the air from the drying zone is used as final rinse. The slats of the blind are held at a slight angle to improve drainage and prevent sag or the blind below the edge of the belt.

Abstract: A cleaning method and cleaning system using an organic solvent such as Freon. A cleaning tank is closed after an article to be cleaned is placed within the cleaning tank. The solvent is supplied to the cleaning tank from a solvent storage tank. The article is cleaned with the supplied solvent. After the cleaning, the solvent is discharged in liquid state from the cleaning tank while vapor of the solvent which remains in the cleaning tank is discharged to a condenser to condense the vapor. The condensed solvent is returned from the condenser into the solvent storage tank. After the liquid solvent and vapor solvent are discharged from the cleaning tank, the cleaned article is taken out from the cleaning tank. The condenser is incorporated in a distiller. A solvent vapor supplying unit is connected to the cleaning tank. The thus provided closed system prevents release of Freon to the atmosphere.

Abstract: Azeotrope-like compositions comprising 1,1-dichloro-1-fluoroethane; dichlorotrifluoroethane; and methyl formate are stable and have utility as degreasing agents and as solvents in a variety of industrial cleaning applications including cold cleaning and defluxing of printed circuit boards.

Abstract: Azeotropic mixtures of n-perfluorobutylethylene and cis-1,2-dichloroethylene with methanol or ethanol or isopropanol, the azeotropic mixtures being useful as: cleaning agents, blowing agents, refrigerants, aerosol propellants, heat transfer media and power cycle working fluids.

Abstract: Stable azeotrope-like compositions comprising dichlorotrifluoroethane, cyclopentane and nitromethane which are useful in a variety of industrial cleaning applications.

Abstract: Stable azeotrope-like compositions consisting essentially of 1,1-dichloro-1-fluoroethane, dichloromethane and optionally alkanol which are useful in a variety of industrial cleaning applications and one of which is also useful as a blowing agent in the preparation of polyurethane foams.

Abstract: An azeotrope or azeotrope-like composition of 2,2-dichloro-1,1,1-trifluoroethane (HCFC-123) and methanol, the azeotropic mixture being useful in solvent cleaning application.