Abstract: A porous membrane of vinylidene fluoride resin, having two major surfaces sandwiching a certain thickness, including a dense layer which governs filtration performance on the one major surface side and a sparse layer which contributes to reinforcement on the other opposite major surface side, and having an asymmetrical gradient network texture including pore sizes which increase continuously from the one major surface to the other opposite major surface, wherein the dense layer includes a 7 ?m-thick portion contiguous to the one major surface showing a porosity A1 of at least 50%, and the one major surface shows a pore size of at most 0.30 ?m. The vinylidene-fluoride-resin porous membrane is generally useful as a porous membrane for separation and particularly exhibits good water-permeation-rate retentivity even in continuous filtration of cloudy water.

Abstract: An object of the present invention is to provide a method for manufacturing a hollow fiber module that makes it possible to decrease the spacing between a plurality of hollow fiber sheets and facilitate the formation of a potting portion with a two-layer structure.

Abstract: The disclosed subject matter provides a composite semiconductor device which can include a common substrate, a first semiconductor light emitting structure, and a second semiconductor light emitting structure. The first semiconductor light emitting structure can include an epitaxial grown layer containing a light emitting layer formed on part of the common substrate either directly or via a bonding layer. The second semiconductor light emitting structure can be provided in a notch at at least one location to which the epitaxial grown layer is not bonded, or in a recess formed in the notch at one location. The disclosed subject matter also provides a method of manufacturing a composite semiconductor device having the above-described and other structures.

Abstract: The object of the invention is to provide: a screen-like object made of hollow fibers, a method of manufacturing a hollow fiber bundle, a cylindrical module of hollow fiber membrane, and an immersion type module of hollow fiber membrane wherein the hollow fibers are easy to bundle while keeping fiber-to-fiber intervals. The screen-like object made of hollow fibers includes: porous hollow fibers 10 disposed parallel at even intervals, tapes 26 for tying together the hollow fibers respectively at both ends of the hollow fibers, and a water-soluble tape for tying together the hollow fibers at a position apart from both ends of the hollow fibers across the hollow fibers.

Abstract: A composition is formed by blending a vinylidene fluoride resin having a relatively high molecular weight and an improved crystallinity represented by a difference Tm2?Tc of at most 32° C. between an inherent melting point Tm2 and a crystallization temperature Tc of the resin with a plasticizer and a good solvent for vinylidene fluoride resin, and the composition is melt-extruded into a hollow fiber-form. The hollow fiber-form extrudate is then cooled to be solidified from an outside thereof by introduction into cooling medium and subjected to extraction of the plasticizer and stretching, thereby forming a hollow fiber porous membrane of vinylidene fluoride resin characterized by co-presence of crystal oriented portion and crystal non-oriented portion recognizable by X-ray diffraction method.

Abstract: A hollow-fiber porous membrane, comprising a hollow fiber-form porous membrane of vinylidene fluoride resin providing: a ratio F (L=200 mm, v=70%)/Pm4 of at least 7×105 (m/day·?m4), wherein the ratio F (L=200 mm, v=70%)/Pm4 denotes a ratio between F (L=200 mm, v=70%) which is a value normalized to a porosity v=70% of a water permeation rate F (100 kPa, L=200 mm) measured at a test length L=200 mm under the conditions of a pressure difference of 100 kPa and a water temperature of 25° C. and a 4-th order value Pm4 of an average pore size Pm. The hollow-fiber porous membrane has an average pore size smaller than before leading to an improved ability of removing fine particles, while suppressing the lowering in water permeability.

Abstract: A semiconductor device manufacturing method can produce semiconductor light emitting/detecting devices that have high connective strength and high luminous energy by increasing contact areas of electrodes thereof and decreasing enclosed areas of electrodes thereof. A wafer is provided with a semiconductor substrate and a semiconductor epitaxial layer. A plurality of substrate concave portions and epitaxial layer concave portions are formed on the semiconductor substrate and the semiconductor epitaxial layer, respectively. Substrate electrodes and epitaxial layer electrodes are formed in the substrate concave portions and the epitaxial layer concave portions. A substrate surface electrode and an epitaxial layer surface electrode can be formed on the semiconductor substrate and the substrate electrodes and the semiconductor epitaxial layer and the epitaxial layer electrodes, respectively.

Abstract: The object of the invention is to provide: a hollow fiber bundle, a method of manufacturing the hollow fiber bundle, a cylindrical module of hollow fiber membrane, and an immersion type module of hollow fiber membrane wherein the hollow fibers are easy to apply scrubbing while maintaining specified intervals among the hollow fibers.

Abstract: A hollow-fiber porous membrane comprising a hollow-fiber form of vinylidene fluoride resin and satisfying the following properties (A) and (B), is provided as a hollow-fiber porous membrane of vinylidene fluoride resin having an average pore size and a further uniform pore size distribution (A) and a large water permeation rate regardless of good efficiency of blocking minute particles (bacteria) (B), as represented by: (A) a ratio Pmax (1 m)/Pm of at most 4.0 between a maximum pore size Pmax (1 m) measured at a test length of 1 m according to the bubble point method and an average pore size Pm of 0.05-0.

Abstract: Monofilaments comprising resin compositions which contain 1% by mass or more of a comonomer component (for example, hexafluoropropylene), have an intrinsic viscosity of 1.3 dl/g or more and a melting point of 165° C. or higher and contain a PVDF-based resin. Owing to the above composition and physical properties, the crystallinity and elastic modulus of the PVDF-based resin are altered. As a result, an appropriate flexibility can be imparted to the monofilaments while preventing deterioration in the mechanical properties.

Abstract: A hollow-fiber porous membrane, comprising a hollow fiber-form porous membrane in a network texture of vinylidene fluoride resin showing a pore size distribution in a direction of its membrane thickness including an outer surface-average pore size P1 as measured by a scanning electron microscope and a membrane layer-average pore size P2 as measured by half-dry method giving a ratio P1/P2 of at least 2.5. The hollow-fiber porous membrane is excellent in long-term water filtration performance including efficiency of regeneration by air scrubbing. The hollow-fiber porous membrane is produced through a process, wherein a mixture of vinylidene fluoride resin, a plasticizer and a good solvent for vinylidene fluoride resin, is melt-extruded in a hollow-fiber film and cooled and formed into a solidified film within a cooling medium containing at least a certain proportion of a good solvent for vinylidene fluoride resin.

Abstract: There is provided a porous hollow fiber of vinylidene fluoride resin which has a water permeation rate that is large per fiber and little dependent on the length, has a large treatment capacity per volume of a filtering module, and is therefore suitable as a microfilter element. That is, a porous hollow fiber, comprising a vinylidene fluoride resin having a weight-average molecular weight of at least 3×105, having a water permeation rate F (m3/m2·day) measured at a pressure difference of 100 kPa and at a water temperature of 25° C. in a range of test length L=0.2-0.8 (m) and expressed in a linear relationship with the test length L of: F=C·L+F0 (formula 1) and satisfying requirements (a)-(d) shown below: (a) a average slope C (/day) of: ?20?C?0, (b) an intercept (basic permeability) F0 (m3/m2·day) of: F0?30, (c) a relation between F0 (m3/m2·day) and an average pore diameter P (?m) according to half-dry method of F0/P?300, and (d) an outer diameter of at most 3 mm.

Abstract: An object of the present invention is to provide a potting agent that enables the reduction of crawling and ensures sufficient penetration between the porous hollow fibers in stationary potting. The potting agent of the present invention is a potting agent for fixing an end portion of a porous hollow fiber group composed of a plurality of porous hollow fibers, and contains a resin material and a filler. The content of the filler is equal to or less than the content of the filler at a rising point of a variation curve of viscosity of the potting agent to filler content.

Abstract: A vinylidene fluoride resin having a weight-average molecular weight as relatively high as 300,000 or higher is mixed with a plasticizer and good solvent for the vinylidene fluoride resin to obtain a composition. A molten extrudate of the composition in a hollow-fiber membrane state is contacted, on its outer side, with a cooling liquid inert to the vinylidene fluoride resin to thereby cool the extrudate. During the solidification, the vinylidene fluoride resin is moderately and mildly crystallized. Thus, a hollow-fiber porous vinylidene fluoride resin membrane is produced which has a high crystallinity represented by an enthalpy of crystal melting 58 J/g or higher. The hollow-fiber porous membrane obtained is excellent in mechanical strength represented by tensile strength and elongation at break and in chemical resistance. It is effectively used as a water microfiltration membrane.

Abstract: A hollow-fiber porous membrane comprising a hollow fiber-form porous membrane of vinylidene fluoride resin and having an average pore size Pm of 0.05-0.20 ?m, a maximum pore size Pmax giving a ratio Pmax/Pm of at most 2.0 between the maximum pore size Pmax and the average pore size Pm and a standard deviation of pore size distribution of at most 0.20 ?m based on a pore size distribution according to the half dry/bubble point method (ASTM•F316 and ASTM•E1294) is provided, as a hollow-fiber porous membrane of vinylidene fluoride resin having minute pores with a size (average pore diameter) and a further uniform pore size distribution suitable for water (filtration) treatment.

Abstract: A porous membrane for water treatment of the present invention is made of a resin composition containing 100 parts by weight of a polyvinylidene fluoride based resin, and 5 to 13 parts by weight of a polyvinyl alcohol based polymer having a degree of saponification of 10 to 80 mol %. The porous membrane has a permeation wetting tension of 38 to 72 mN/m, and a tensile strength of 7 to 20 MPa, and thus is characterized by having the excellent mechanical strength and wettability. This is a porous membrane for water treatment essentially containing the polyvinylidene fluoride based resin, which allows water treatment to be highly efficiently performed on raw water (river water, industrial waste water, and the like), in particular.

Abstract: There is provided a porous membrane of vinylidene fluoride resin which has pores of appropriate size and distribution and also excellent mechanical strength represented by tensile strength and elongation at break and is useful as a microfiltration membrane or a separator for batteries. The porous membrane of vinylidene fluoride resin is characterized by the presence in mixture of a crystalline oriented portion and a crystalline non-oriented portion as confirmed by X-ray diffraction, and is produced by subjecting a melt-extruded composition obtained by mixing a vinylidene fluoride resin having a molecular weight distribution which is appropriately broad and high as a whole with a plasticizer and a good solvent for vinylidene fluoride resin, to cooling for solidification from one surface, extraction of the plasticizer and stretching.

Abstract: The disclosed subject matter provides a composite semiconductor device which can include a common substrate, a first semiconductor light emitting structure, and a second semiconductor light emitting structure. The first semiconductor light emitting structure can include an epitaxial grown layer containing a light emitting layer formed on part of the common substrate either directly or via a bonding layer. The second semiconductor light emitting structure can be provided in a notch at at least one location to which the epitaxial grown layer is not bonded, or in a recess formed in the notch at one location. The disclosed subject matter also provides a method of manufacturing a composite semiconductor device having the above-described and other structures.

Abstract: A semiconductor device manufacturing method can produce semiconductor light emitting/detecting devices that have high connective strength and high luminous energy by increasing contact areas of electrodes thereof and decreasing enclosed areas of electrodes thereof. A wafer is provided with a semiconductor substrate and a semiconductor epitaxial layer. A plurality of substrate concave portions and epitaxial layer concave portions are formed on the semiconductor substrate and the semiconductor epitaxial layer, respectively. Substrate electrodes and epitaxial layer electrodes are formed in the substrate concave portions and the epitaxial layer concave portions. A substrate surface electrode and an epitaxial layer surface electrode can be formed on the semiconductor substrate and the substrate electrodes and the semiconductor epitaxial layer and the epitaxial layer electrodes, respectively.

Abstract: A composition is formed by blending a vinylidene fluoride resin having a relatively high molecular weight and an improved crystallinity represented by a difference Tm2?Tc of at most 32° C. between an inherent melting point Tm2 and a crystallization temperature Tc of the resin with a plasticizer and a good solvent for vinylidene fluoride resin, and the composition is melt-extruded into a hollow fiber-form. The hollow fiber-form extrudate is then cooled to be solidified from an outside thereof by introduction into cooling medium and subjected to extraction of the plasticizer and stretching, thereby forming a hollow fiber porous membrane of vinylidene fluoride resin characterized by co-presence of crystal oriented portion and crystal non-oriented portion recognizable by X-ray diffraction method.