Abstract: Disclosed are a paper support as well as a recording paper comprising the paper support and as formed thereon a recording layer, particularly a heat-sensitive recording layer, a transfer receiving layer for thermal fusion transfer recording or sublimation transfer recording or an ink receiving layer for ink-jet recording, the paper support having a security element embedded therein, the security element being a thread-shpaed or ribbon-shaped security element, and the paper support having a thickness which is at least 3 times the diameter of the thread-shaped security element or at least 3 times the thickness of the ribbon-shaped security element.

Abstract: A wave absorber is provided which has a wave absorption characteristic of 20 dB in a frequency band of 1 GHz to 20 GHz, is nonflammable, compact and lightweight, and has excellent durability. A porous ferrite is produced as the base material for which is an Ni--Zn type ferrite which has an excellent wave absorption characteristic in the high frequency range, and this serves as a wave absorber formed in the shape of a pyramid or triangular prism.

Abstract: A polyester resin composition comprises: an aliphatic polyester having a number-average molecular weight (Mn) in a range of 10,000 to 100,000; and a crystalline nucleating agent, wherein the aliphatic polyester and the crystalline nucleating agent are mixed in such that a half value width of an exothermic peak based on an annealing crystallization of the aliphatic polyester measured by differential scanning calorimetry in an atmosphere of nitrogen at a cooling rate of 3K/minute is not more than 15K. This polyester resin composition has a biodegradability and a high crystallization rate. The polyester resin composition also has excellent mechanical properties and eliminates a precise temperature control during a molding process which saves labor force resulting in desirable moldability and productivity. For the described beneficial properties, the polyester resin composition can be readily processed into a fiber, a molded article, sheet, film and the like.