Vinylidene fluoride resin porous membrane, manufacturing method therefor, and method for manufacturing filtrate water
US9096957B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 8, 2010 |
| Grant date | Aug 4, 2015 |
| Priority date | — |
| Expiry date | Nov 10, 2032 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W10/10
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A porous membrane of vinylidene fluoride resin, including a 10 μm-thick portion contiguous to one surface thereof which comprises network resin fibers having an average diameter of at most 100 nm and shows a porosity A1 of at least 60% as measured by a focused ion beam-scanning electron microscope, and showing a surface pore size of at most 0.3 μm on said one surface thereof. The porous membrane has a treated water side surface layer showing a small surface pore size suitable for water filtration treatment and formed of extremely thin network resin fibers giving an extremely high porosity, thus showing an excellent minute particle-blocking performance and also extremely good anti-soiling resistance and regeneratability. The porous membrane is produced by a process including: melt-extrusion of a composition obtained by adding to vinylidene fluoride resin of a large molecular weight a relatively large amount of a polyester plasticizer which is mutually soluble with the resin and provides the resultant mixture with a crystallization temperature that is substantially identical to that of the vinylidene fluoride resin alone to form film, followed by cooling from one side of the film to …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.