1,3 : 2,4-Di-O-benzylidene-d-sorbitol (d-DBS) can cause gelation of organic solvents of a wide range of polarity into a gel state. The aggregated structures of d-DBS/organic solvent systems were studied, mainly by using IR, UV, and circular dichroism (CD) spectroscopy. In the case of the racemate Dl-DBS, no gel state was formed. In IR spectra of d-DBS and Dl-DBS in the solid state, the intensities of νOH and νCO absorption in d-DBS were found to be larger than those in Dl-DBS. It is assumed that the hydrogen bonding formed between an acetal oxygen and a hydroxyl group in the aggregation of d-DBS. From the changes in the IR spectra from solution into a gel state, we can conclude that the chirality and the hydrogen bonding of DBS molecules are essential for the formation of the gel. Comparing the gel-forming ability of d-DBS with its derivatives, 5- or 6-hydroxyl-group-blocked compounds by methyl group, the 6-hydroxyl group seems to be important in the formation of d-DBS aggregates. The results of UV spectra suggest that the benzene rings are ordered in a side by side arrangement. The molar ellipticities in CD spectra increased about 500 times during the change from the solution to the gel state. From these results, it is concluded that d-DBS forms a helical structure of thin fibrous crystals in the gel state.

Monoalkyl phosphates of high purity were synthesized and were investigated for their surface‐active properties and cutaneous effects. It has been found that these surfactants possess adequate surface‐active properties similar to those of common anionic surfactants and that they exhibit considerable safety on the skin in comparison with typical anionic surfactants used commercially.

1,3 : 2,4-Di-O-benzylidene-d-sorbitol (d-DBS) is known as a chiral oil gelator for a wide variety of organic solvents. The relationship between texture, structure of the gel, and the aggregated structure formed by d-DBS was investigated in various solvents. In the low polar solvents, the gel held a mesh type network structure in which the fiber appeared to be a rope-like helical structure. In the moderately polar solvents, the gel held an isotropic mesophase, but in the polar solvents, a spherulite texture was observed. From the experiments for the critical gel concentration of d-DBS in various solvents, it is assumed that there are three regions that differ in the form of hydrogen bonding, depending upon the polarity of solvents. By IR spectroscopic measurements, we found that, with the increase of solvent polarity, the hydrogen bonding between d-DBS and the solvent became more predominant than the intramolecular hydrogen bonding, and the hydrogen bonding between d-DBS became weaker at the same time. In addition, the intensities of CD spectra in the d-DBS gel decreased according to the increase of the solvent polarity. Here it is considered that textures and structurs observed in the gel are related to the aggregated structure that is mainly formed through hydrogen bonding among d-DBS.

1,3 : 2,4-Di-O-benzylidene-d-sorbitol (d-DBS) is known to be a chiral oil gelator which forms the gel state with organic solvents having a wide range of polarities. Microscopic and thermoanalytical studies on the binary system, d-DBS/ethylene glycol, were carried out. The gel of the d-DBS/ethylene glycol system showed optical anisotropy under crossed polarizers. Two kinds of mesophases have been identified in the gel state. One was the crystalline phase, by means of observing the spherulitic texture. The other was an isotropic mesophase between spherulitic textures. In the crystalline phase the supramolecular helicoidal strucrture was observed by polarized and electron microscopy. The isotropic mesophase comprized of a network-like structure. It changed to the crystalline phase below the phase transition temperature from a gel to an isotropic solution (Ti), and the crystal of d-DBS was precipitated out from ethylene glycol. It is thus concluded that the gel state of d-DBS/ethylene glycol is a metastable state and that the chirality of d-DBS affects the shape which d-DBS forms in the crystalline state.

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