E.i. Dupont De Nemours and Company

Harold L Jackson

Frederick W Mader

Kenneth T Dishart

George R Coraor

Mark C Wolff

Abraham B Cohen, Deceased

A purified form of adipic acid containing 0.1 to 2.0 ppm of copper in the form of an ionic copper compound that is useful in the formation of nylon polymer, nylon yarns, and polyester polyols of low color.

Copper-modified high purity adipic acid

A cleaning composition is disclosed which is suitable for cleaning substrates and particularly for cleaning flux residues from a printed circuit board. The cleaning composition comprises a hydrocarbon component, a compatibilizing agent, a multibasic ester additive, and optionally water. The multibasic ester may be an alkanoic acid ester of a diol or polyol, an alkanoic acid ester of a hydroxy alkanoate alkyl ester, or and alkyl ester of a compound containing two or more carboxylic acid groups and one or more hydroxyl groups which are optionally esterified with an alkanoic acid group. The cleaning composition may be used as a solution or as an emulsion or dispersion to clean a substrate.

Cleaning composition of hydrocarbon component, surfactant and multibasic

A cleaning composition is disclosed which is suitable for cleaning flux residue from a printed circuit board and comprises dibasic ester, a hydrocarbon solvent, a compatibilizing surfactant and water.

Cleaning composition of dibasic ester, hydrocarbon solvent,

A low toxicity paint remover composition containing C.sub.1 to C.sub.4 dialkyl esters of C.sub.4 to C.sub.6 aliphatic dibasic acid, an activator, a thickener, a surfactant and at least one other organic nonhalogen-containing solvent.

Paint remover

Process of drying water-wet solid materials, which process comprises, in a system, A. forcibly contacting the water-wet solid material with circulating vapor of a fluorocarbon having a fluorine to carbon atom ratio of at least 1.0 and a boiling temperature of less than about 80.degree. C at atmospheric pressure, said fluorocarbon vapor being at a temperture above about 100.degree. C and said contacting being carried out in the absence of a substantial amount of a noncondensable gas, such as air or nitrogen, B. passing the resulting mixture of fluorocarbon vapor and water vapor from step (a) through a zone maintained at a temperature less than 100.degree. and at least 1.degree. C above the atmospheric pressure boiling temperature of the fluorocarbon to condense a substantial portion of the water vapor but not a substantial portion of the fluorocarbon vapor and, preferably, so that the partial pressure of the water in the remaining vapor mixture is less than about 25 cm of mercury, C. heating the vapor mixture from step (b) to a temperature above about 100.degree. C and recycling the mixture to step (a), D. repeating steps (a), (b) and (c), while maintaining substantially constant in the system the amount of fluorocarbon vapor, until the solid material is substantially free of water and contains only fluorocarbon vapor on its surfaces and/or occluded in its interstices, and thereafter E. removing and recovering from the solid material the fluorocarbon vapor values and F. recovering solid material which is substantially free of water and fluorocarbon.

Drying of water-wet solid materials

Fluorocarbon dye dispersion comprising an organic disperse dye; a certain normally liquid fluorocarbon having a fluorine to carbon atom ratio of at least 1.5, a solubility parameter of not greater than 7.0 and a critical temperature of at least 135.degree. C., and, optionally, an effective amount of a compound having both surface activity and solubility in the normally liquid fluorocarbon, said dye dispersion being useful in the exhaust dyeing of disperse dyeable synthetic polymers, in the form of films, fibers or fabrics, by the process comprising contacting the polymer with the dye disperson at a temperature above the glass transition temperature of the polymer for a sufficient time to exhaust the dye onto the polymer.

Fluorocarbon dye dispersion for exhaust disperse dyeing

Non-aqueous process for improving a functional property of flexible, natural and synthetic, organic polymeric substrates, such as textiles, film and paper, for example, polyethylene terephthalate or cotton fabric, by applying thereto an agent other than a dye, which agent is capable of imparting the desired improved functional property to the substrate, which process comprises:

Rapid fixation of agents on flexible substrates

Process for continuously transferring heat to a moving band of solid material, for example, a textile, a film, particles, or any shaped or unshaped article, the band preferably comprising a disperse dyeable synthetic polymer, for example, a polyester or polyamide, said process comprising passing the band through a substantially enclosed purging-drying region containing the superheated condensable vapor of a liquid having an atmospheric pressure boiling point of less than 120.degree. C., thence immediately thereafter through a substantially enclosed, heat-transfer region containing the superheated condensable vapor of a fluorocarbon having a fluorine to carbon atom ratio of at least 1.5, a solubility parameter of not more than 6.5 and a molecular weight of at least about 300, the pressure in the heat transfer region being no greater than that in the purging-drying region, thence immediately thereafter through a substantially enclosed purging region containing dry steam, the pressure in the purging region being no less than that in the heat-transfer region, and thereafter recovering the band of material, said process characterized by efficient heat transfer resulting from rapid convective movement of superheated fluorocarbon in the heat-transfer region and by minimum loss of such vapor to the atmosphere.

Process for continuously transferring heat to a moving band

Stable concentrated dispersion of dye and/or textile finishing agent in liquid or solid media, suitable for dilution with a fluorocarbon to form a stable, non-aqueous textile treating bath.

Textile treating dispersion concentrate

Textile drying process comprising continuously contacting a moving textile web, which is wet with a first fluorocarbon liquid having a textile agent dispersed therein, with the superheated vapors of a second fluorocarbon liquid, the superheated vapors being at a temperature such that no substantial amount of second fluorocarbon liquid condenses on the web, to evaporate substantially all of the first fluorocarbon liquid from the web in no more than seven seconds without causing substantial migration of the textile agent on the web, said first and second fluorocarbon liquids being selected from fluoro and chlorofluoro substituted aliphatic and cycloaliphatic hydrocarbons, ethers and tert.-amines wherein the ratio of hydrogen atoms to halogen atoms is 0 - 0.2, the first fluorocarbon liquid having a boiling point of 20.degree. - 110.degree. C. and the second fluorocarbon liquid having a boiling point of 20.degree. - 220.degree. C.

Migration-free textile drying

Process for substantially quantitatively removing and recovering a volatile, organic, water-immiscible wetting liquid from a solid material which is wet therewith, which process comprises intimately contacting the solid material first with the superheated vapor of a water-immiscible, organic stripping liquid and thereafter with dry steam, said contacting taking place in an environment substantially free of noncondensable gas, condensing the mixture of organic vapor and steam to form a two-phase liquid mixture consisting of liquid organic phase and liquid water phase, and separating the liquid organic phase and the liquid water phase.

Process for recovering volatile organic liquids

Process, suitable for drying water-wet porous materials, for example, textiles, which comprises forcing a displacement liquid through the open interstices of the water-wet porous material to remove the water, the displacement liquid consisting of a water-immiscible, normally liquid organic solvent having a surface-active agent dissolved therein, said displacement liquid having at 25.degree.C. an interfacial tension versus water of no greater than about 10 dynes cm..sup..sup.-1 at 25.degree.C., a density of at least about 1.25 grams cm..sup..sup.-3 and an advancing adhesion tension versus platinum which is positive, and recovering porous material whose open interstices are substantially free of liquid water.

Process for drying porous materials

Process wherein an organic disperse dye is applied, for example, to a synthetic organic polymer in the form of a film or textile fabric, for example, a polyethylene terephthalate fabric, by printing, spraying or padding and the dye-containing film or fabric is then passed through a fluorocarbon fluid at atmospheric pressure and at a temperature greater than the glass transition temperature of the polymer, said fluorocarbon having a boiling temperature of at least 125.degree.C., a fluorine to carbon atom ratio of at least 1.5 and a solubility parameter of not greater than 7.0, preferably 6.5 or less, for example, a fluorocarbon of the formula F[CF(CF.sub.3)CF.sub.2 O].sub.n CHFCF.sub.3 wherein n is at least 3.

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Hockessin, DE, United States of America

Harold L Jackson