Eric Jungermann

Contact angle studies on viable human skin: II. Effect of surfactant ionic type in pretreatment

The effect of presoaking with various surfactant solutions on the skin-water contact angle was investigated. Various cationic surfactants and amine oxides were found to lower the skinwater contact angle at lowest concentrations. Rinsability data supported the findings and suggested that cationic surfactants are tightly bound to the skin.

Establishment of a standardized detergency evaluation method

This paper describes a standardized laboratory procedure for determining the fabric soil-removal efficiency of heavy-duty detergents. A careful analysis of machines, standard soil fabrics, operating times, and water hardness had led to the standardization of technique. The precision of the method has been presented for tests carried out in hard and soft water on two anionic heavy-duty detergents at a concentration of 0.2%. Standard deviations of 0.74% for a water hardness of 50 p.p.m. and 1.03% for a water hardness of 135 or 300 p.p.m. have been obtained.

Performance evaluation of selected fabric softeners

Some methods and variables of importance in softener evaluation were examined. A subjective, paired-comparison panel method is recommended for softening measurement, and a dye wicking method seems most reliable for rewettability measurement. Use of these methods shows that softening tends to decrease and rewettability to increase with unsaturation and introduction of ether groups in bridging radicals and with reduction of alkyl chain length, in a word with increasing hydrophilicity of various radicals. Rewet data are particularly sensitive to these effects. For excellent softening, two long chain alkyl groups are apparently required, and these should be at least C16 and more preferably C18 in length.

Quantitative gas chromatography of fatty derivatives. Relative detector responses to C6−C14 saturated methyl esters

The ralative response of a thermal conductivity cell, in terms of peak area produced per mole of compound, has been determined for the fatty methyl esters caproate through myristate. The values were found to be a linear function of molecular weight.

Statistical approach to detergency. III. Effect of artificially soiled test cloth

The relative effectiveness of several proprietary detergents is measured in cleaning “standard” soil cloths. Quantities of soil removal are related to detergent type, and to polarity or hydrophilicity of the soil and cleaning media. Various calculation methods and statistical treatments of detergency data are discussed.

Effect of tallow-coconut fatty acid ratios on properties of bar soaps

In this study, blends of tallow and coconut fatty acids prepared at ratios ranging from 95:5 to 75:25 were converted to sodium soaps, and were processed into soap bars through conventional milling and pressing techniques. Other minor ingredients were included in the bar to protect against rancidity and to provide color. The resulting bars were tested for lather, solubility, penetration, swell, slushing tendency, moisture and cracking. According to one mechanical method, the 85:15 tallow/coconut fatty acid blend yields optimum lather quickness. This does not agree with lather preference by an expert panel which preferred bars with increasing sodium cocoate content or with increasing levels of sodium laurate. Coincident with these effects was an increase in aqueous solubility. However, certain deleterious effects were observed with increase of sodium cocoate, namely: increased slushing and a higher erosion rate.

The reactions of hydrogen bromide with oleic acid and its esters. II. Free radical addition

SummaryOleic acid and a series of its esters were reacted with hydrogen bromide under conditions favoring addition by a free radical mechanism. Variations of the solvents, catalysts, temperatures, dilution, and the ester groups were investigated. Under all conditions a statistical 50∶50 distribution of position isomers was found.

A new broad spectrum antibacterial soap I. General properties

The first soap germicide system to show activity against gram-negative organisms is described. Addition of a new germicidal agent, 2-hydroxy-2′,4,4′-trichlorodiphenyl ether, combination of hexachlorophene and triclocarban which has been used in a soap known to be effective against gram-positive organisms, has broadened its antibacterial spectrum without impairing its mildness, safety and other desirable bar soap characteristics. Properties of the new system, including in vitro and in vivo tests of its antibacterial activity, efficacy and safety, are discussed.

Identification of soapstocks by gas chromatographic techniques

The stock of a given soap may be estimated when the ratios of the fatty acids present are known. A new gas chromatographic procedure utilizing a novel automatic attenuator is presented. The samples are prepared by refluxing the soap with a methanolic solution of boron trifluoride and separating the esters so formed by standard gas-liquid chromatographic procedures. Soapstock compositions are determined by comparison with reference curves.Summary1)In tallow-coconut soapstocks vapor-phase chromatographic techniques are superior in accuracy and less time-consuming than conventional physical-chemical methods.2)For stocks containing other than tallow and coconut base, or where partial hydrogenation has been carried out, vapor-phase chromatography gives a more complete picture.3)Vapor-phase chromatography gives indications of the source and/or prior treatment of a given stock.

Statistical approach to detergency evaluation. Correlation of performance data with gas chromatographic patterns of alkylbenzenes

The precision of a standardized detergency test based on the use of a Tergotometer and U.S. Test Cloth was found at a concentration of 0.4 and 0.5%. At these concentrations, the standard deviation was 0.56% soil removal units, and precision at a 95% confidence limit was±1.12% soil removal units.The detergency of some built spray-dried detergents was examined by this method and found to differ significantly, though chemical compositions were identical. Gas chromatographic analysis of the alkylbenzenes obtained by desulfonation of the alkylbenzene sulfonates indicated small structural variations which correlated with the observed variations in the detergency.