Abstract: A novel black coloring material is obtained by treating a chitosan with a dyestuff of the lithospermum root. If a water-insoluble chitosan is used as the chitosan, a finely divided black coloring material is obtained, and if a gelatinous chitosan salt is used as the chitosan, a gelatinous black coloring material is obtained. If a water-soluble chitosan, chitosan oligosaccharide or D-glucosamine, or a salt thereof is used as the chitosan, a liquid black coloring material is obtained. If a powdery polymeric substance is treated with such a black coloring material, a polymer-based black coloring material is obtained, and if a fiber is dyed with such a black coloring material, the fiber is dyed to a black color having a low lightness.

Abstract: A polygon-shaped house is composed of a foundation frame having a symmetrical polygonal shape; columns the lower ends of which are connected to the polygon-shaped foundation frame at vertices of the foundation frame; a beam frame disposed over and in parallel with the foundation frame having a polygonal shape similar to that of the foundation frame, said beam frame being connected at its vertices to the upper ends of the corresponding columns; angle rafters whose lower end portions are connected to the beam frame respectively at the vertices of the beam frame and whose upper ends extend obliquely and upwardly toward a position over the center of the beam frame; and a weighty post member supported by the upper ends of the angle rafters, said upper ends being connected to the post member, and exerting downward force on the angle rafters by its own weight. The polygon-shaped house is simple in framework, permits its easy construction, has sufficiently high strength, and provides a wide free space.

Abstract: A modular house is composed of eight columns to be provided upright respectively at eight points, each two of which divide each side of an imaginary square on a piece of land into three equal parts, and panels to be attached to the columns. The modular house is of an extremely simple structure, requires a low cost for its manufacture, permits effective utilization of land and easy enlargement and/or remodeling, and provides a wide interior floor area.