Abstract: A high-purity gas for plasma reaction having an octafluorocyclopentene purity of at least 99.9% by volume based on the total volume of the gas for plasma reaction, wherein the total content of nitrogen gas and oxygen gas, contained as trace gaseous ingredients of the remainder, is not larger than 200 ppm by volume. This high-purity gas for plasma reaction can be produced by (1) a process of distilling crude octafluorocyclopentene in an inert gas of group 0, or (2) a process of distilling crude octafluorocyclopentene into a purity of at least 99.9% by volume, and then, removing an impurity remainder.

Abstract: A high-purity gas for plasma reaction having an octafluorocyclopentene purity of at least 99.9% by volume based on the total volume of the gas for plasma reaction, wherein the total content of nitrogen gas and oxygen gas, contained as trace gaseous ingredients of the remainder, is not larger than 200 ppm by volume. This high-purity gas for plasma reaction can be produced by (1) a process of distilling crude octafluoro-cyclopentene in an inert gas of group 0, or (2) a process of distilling crude octafluorocyclopentene into a purity of at least 99.9% by volume, and then, removing an impurity remainder.

Abstract: A high-purity gas for plasma reaction having an octafluorocyclopentene purity of at least 99.9% by volume based on the total volume of the gas for plasma reaction, wherein the total content of nitrogen gas and oxygen gas, contained as trace gaseous ingredients of the remainder, is not larger than 200 ppm by volume. This high-purity gas for plasma reaction can be produced by (1) a process of distilling crude octafluorocyclopentene in an inert gas of group 0, or (2) a process of distilling crude octafluorocyclopentene into a purity of at least 99.9% by volume, and then, removing an impurity remainder.

Abstract: A dressing for a wound having a porous structure of continuous pores throughout the dressing made of minute filaments arranged in three dimensions and filmy links (viewed at a magnification of about 35 to 350) connecting the filaments. The porous structure has pores defined by the filmy interconnections. In other words, the wound dressing has a continuous open-celled structure in an expanded foam. The wound dressing can advantageously be made of a highly biocompatible material, such as poly-.alpha.-amino acid.

Abstract: A method of manufacturing a wound dressing having microscopic web-like interconnections and a porous structure of continuous pores throughout the wound dressing. In the first embodiment of the method, the dressing is produced by the steps of heating while simultaneously stirring a biocompatible material and solvent to form a homogenous solution; cooling while simultaneously stirring the homogenous solution to form a gel made of a dispersion of gel particles of the biocompatible material and freeze-drying the gel. In a second embodiment of the method, the wound dressing is produced by heating while simultaneously stirring a biocompatible material and the solvent to form a homogenous solution, cooling while simultaneously stirring the homogenous solution to form a gel made of a dispersion of gel particles of the biocompatible material; warming while simultaneously stirring the gel, allowing the warm gel to cool to form a soft gel and freeze-drying the soft gel.