Abstract:
In order to replace 1,1,2-trichloro-1,2,2-trifluoroethane and 1,1-dichloro-1-fluoroethane in compositions for treating solid surfaces (in particular defluxing), the invention proposes the use of a quasi-azeotropic mixture containing, by weight, from 75 to 95% of 1,1,1,3,3-pentafluorobutane, from 1 to 15% of methylene chloride and from 1 to 10% of methanol.
Abstract:
Azeotropic and azeotrope-like compositions of 142/365 mfc, 142/methanol, and 142/365 mfc/methanol are provided, as are methods for using the same for cleaning, drying, foam blowing and the like.
Abstract:
The use of a mixture of cycloalkanes of general formula C.sub.n H.sub.2 (n+1-a) in which n is an integer ranging from 8 to 12 and a represents the number of rings as agent for cleaning and degreasing solid surfaces, e.g., printed circuits. The mixture has a flash point above 55.degree. C. (ASTM D56-70) and a distillation range of 175.degree. C. to 235.degree. C.
Abstract:
The invention relates to a composition based on stabilized methylene chloride composed essentially of at least one 1,2-epoxyalkane and of at least one acetal, and preferably no nitroalkane.The composition according to the invention can be used for degreasing, cleaning and/or drying metal components.
Abstract:
To replace compositions based on CFC or CFHC in applications for cleaning solid surfaces (in particular defluxing), the invention proposes azeotropic or quasi-azeotropic compositions based on 1,1,1,2,2,4,4-heptafluorobutane and a C.sub.1 -C.sub.3 alcohol.
Abstract:
The invention relates to a composition based on stabilized methylene chloride composed essentially of at least one 1,2-epoxyalkane and of at least one acetal, and no nitroalkane. The composition according to the invention can be used for degreasing, cleaning and/or drying metal components.
Abstract:
To replace cleaning compositions based on 1,1,2-trichloro-1,2,2-trifluoroethane (F113), the invention proposes a composition comprising, by weight, 93 to 99% of 1,1,1,3,3-pentafluorobutane (F365 mfc) and 7 to 1% of methanol. These two compounds form a positive azeotrope (b.p.=36.5.degree. C. at normal pressure).The composition, optionally stabilized, can be used for the cleaning and/or drying of solid surfaces, in particular for the removal of flux from printed circuits and for degreasing mechanical parts.
Abstract:
To replace the cleaning compositions based on 1,1,2-trichloro-1,2,2-trifluoroethane (F113), the invention proposes a composition comprising, on a weight basis, 60 to 90% of 1,1-dichloro-1-fluoroethane (F141b), 9 to 33% of 1,1,1,3,3-pentafluorobutane (F365 mfc) and 1 to 7% of methanol. These three compounds form a positive azeotrope (b.p.=29.1.degree. C. at normal pressure).The composition, optionally stabilized, can be employed for the cleaning and/or drying of solid surfaces, in particular for the defluxing of printed circuits and for the degreasing of mechanical components.
Abstract:
The invention relates to the preparation of 1,1,2,2-tetrahydroperfluoroalkanols and their esters.A 2-(perfluoroalkyl)ethyl iodide is oxidized using peroxomonosulphuric acid or peroxodisulphuric acid in a carboxylic acid or carboxylic acid ester.