Abstract: Hydrophobic poly(4-methyl-1-pentene) hollow fiber membrane for retention of anesthetic agents with an inner and an outer surface and between inner and outer surface an essentially isotropic support layer with a sponge-like, open-pored, microporous structure free of macrovoids and adjacent to this support layer on the outer surface a dense separation layer with a thickness between 1.0 and 3.5 ?m. The membrane has a porosity in the range of greater than 35% to less than 50% by volume and a permeance for CO2 of 20-60 mol/(h·m2·bar), a gas separation factor ?(CO2/N2) of at least 5 and a selectivity CO2/anesthetic agents of at least 150. The process for producing this membrane is based on a thermally induced phase separation process in which process a homogeneous solution of a poly(4-methyl-1-pentene) in a solvent system containing components A and B is formed, wherein component A is a strong solvent and component B a weak non-solvent for the polymer component.

Abstract: Hydrophobic poly(4-methyl-1-pentene) hollow fiber membrane for retention of anesthetic agents with an inner and an outer surface and between inner and outer surface an essentially isotropic support layer with a sponge-like, open-pored, microporous structure free of macrovoids and adjacent to this support layer on the outer surface a dense separation layer with a thickness between 1.0 and 3.5 ?m. The membrane has a porosity in the range of greater than 35% to less than 50% by volume and a permeance for CO2 of 20-60 mol/(h·m2·bar), a gas separation factor ?(CO2/N2) of at least 5 and a selectivity CO2/anesthetic agents of at least 150. The process for producing this membrane is based on a thermally induced phase separation process in which process a homogeneous solution of a poly(4-methyl-1-pentene) in a solvent system containing components A and B is formed, wherein component A is a strong solvent and component B a weak non-solvent for the polymer component.

Abstract: Hydrophobic poly(4-methyl-1-pentene) hollow fiber membrane for retention of anesthetic agents with an inner and an outer surface and between inner and outer surface an essentially isotropic support layer with a sponge-like, open-pored, microporous structure free of macrovoids and adjacent to this support layer on the outer surface a dense separation layer with a thickness between 1.0 and 3.5 ?m. The membrane has a porosity in the range of greater than 35% to less than 50% by volume and a permeance for CO2 of IN 20-60 mol/(h·m2·bar), a gas separation factor ?(CO2/N2) of at least 5 and a selectivity CO2/anesthetic agents of at least 150. The process of for producing this membrane is based on a thermally induced phase separation process in which process a homogeneous solution of a poly(4-methyl-1-pentene) in a solvent system containing components A and B is formed, wherein component A is a strong solvent and component B a weak non-solvent for the polymer component.

Abstract: A photolithographic mask has the advantage that a combination of dummy structures, whose pattern is imaged into the resist layer, and auxiliary structures, whose pattern is not imaged into the resist layer, makes it possible to achieve a significant improvement in the imaging properties of the main structures which are disposed at an edge of a region containing a multiplicity of main structures. In particular, constrictions at the structures can be significantly reduced or completely avoided and/or a so-called “tilting” of the structures under non-optimum focus conditions is significantly reduced or completely avoided.

Abstract: An item of information about the respective positions (501, 502, 601, 602) of at least two structure elements (50, 60) on a mask is provided. The displacement of the positional positions during the imaging by the lens system of the exposure apparatus, the displacement being governed by lens aberration, is measured and correction values (540, 640) are determined for each of the structure elements. Using the correction values (540, 640) the positions (501, 502, 601, 602) are changed in order to form new positions (505, 506, 605, 606) of the structure elements (50, 60) in such a way that the aberration effects can be compensated for. A mask (40) adapted to the exposure apparatus is exposed with the structures at the changed positions. The variation in the positional accuracies and the structure width distributions which is governed by the aberration of lenses is advantageously reduced.

Abstract: A photolithographic mask has the advantage that a combination of dummy structures, whose pattern is imaged into the resist layer, and auxiliary structures, whose pattern is not imaged into the resist layer, makes it possible to achieve a significant improvement in the imaging properties of the main structures which are disposed at an edge of a region containing a multiplicity of main structures. In particular, constrictions at the structures can be significantly reduced or completely avoided and/or a so-called “tilting” of the structures under non-optimum focus conditions is significantly reduced or completely avoided.