In the cementitious materials for construction and architecture, water-soluble polymeric dispersants which is one of the large quantity of polymeric surfactants have been widely used as chemical admixtures, imparting high fluidity to high-strength concrete and soil improvement. In recent years, for the purpose of playing a more advanced role in the progress of construction field, the authors have got down to a new technical development, and fortunately reaped plural rich harvest from the study.
This report relates especially to the following three subjects. (1) Development of chemical admixture comprising from a water-soluble graft copolymer (SP2), namely high-range AE water-reducing agent to produce ultra-high strength concrete for Super-High-Rise RC Structure. (2) Development of hybrid admixtures (HSP1 and HSP2) comprising from single-liquid combining high fluidity and shrinkage-reducing capability for the durability improved concrete. (3) Development of admixture (EF) for soil-cement which is able to impart high fluidity to soil improvement.
First of all in this articles, the fundamental principles, chemical structures, cementitious particle dispersing mechanism and the difference between concrete and soil- cement were reviewed from experiences.

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Mannosylerythritol lipids (MELs), which are amphiphilic glycolipids abundantly produced by yeasts from renewable resources, are one of the most promising biosurfactants because of their excellent surface-active properties and versatile biochemical activities. However, the structural variety of MELs hitherto discovered still remains limited; this makes the broad range of their applications difficult. We thus have been continuously developing new types of MELs with different structures and functions. Recently, we found that novel types of MELs, namely the tri-acylated and mono-acylated MEL, were preferentially obtained by the selection of cultural conditions, respectively. They have different hydrophobic structures and show different interfacial properties compared to the conventional di-acylated MELs. These MEL derivatives show wide hydrophilic-lipophilic balance (HLB) values, and the combination of them makes the wide range of applications possible. On the other hand, we found new MEL derivatives having the carbohydrate configuration different from the conventional MELs, which were selectively produced by specific yeast strains. These new diastereomers show different self-assembling properties and biological actions, and their application to pharmaceutical and cosmetic fields are expected. This study provides these novel MEL derivatives and the methods of their tailor-made production.

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