Serial arrangement having multiple plies of asymmetric filter media, production method, filtration unit, use of the arrangement, and characterization method

Patent metadata

Field	Value
Publication number	US-12115502-B2
Application number	US-201917052692-A
Country	US
Kind code	B2
Filing date	Jun 4, 2019
Priority date	Jun 7, 2018
Publication date	Oct 15, 2024
Grant date	Oct 15, 2024

Abstract

The present invention relates to a serial arrangement comprising n plies of asymmetric filter media, wherein n is at least two and the pore size of the n plies substantially continuously decreases in the thickness direction of the serial arrangement, to a production method for the serial arrangement, to a filtration unit comprising the serial arrangement, to the use of the serial arrangement, and to a method for characterizing the pores of a filter medium.

First claim

The invention claimed is:

1. A serial arrangement of filter media that comprises n plies, wherein
n is 3 to 10,
each of the n plies is an asymmetric filter medium having an asymmetry factor of at least 1.5,
the n plies have an overall asymmetry factor of at least 10,
a pore size of the n plies substantially continuously decreases in a thickness direction of the serial arrangement, and
wherein the arrangement is an assembly composed of n plies of asymmetric filter media which are loosely stacked on top of one another and are, in an edge region of the plies, embedded in a filter housing.

2. The serial arrangement as claimed in claim 1 , wherein each of the n plies is a microporous membrane.

3. The serial arrangement as claimed in claim 1 , the serial arrangement having a thickness of 100 to 1000 μm.

4. The serial arrangement as claimed in claim 1 , wherein the pore size of the n plies decreases linearly, concavely or convexly in the thickness direction.

5. The serial arrangement as claimed in claim 1 , wherein a thickness of the plies is, independently of one another, 50 to 250 μm.

6. The serial arrangement as claimed in claim 1 , wherein the plies are constructed from PVDF, PTFE, cellulose ester, cellulose hydrate, polyamide, polysulfone, polyarylsulfone, polyacrylic acid, polymethacrylic acid, acrylic acid-methacrylic acid copolymer, polyethersulfone or a mixture thereof.

7. The serial arrangement as claimed in claim 1 configured for filtration of viruses and/or for filtration of mycoplasmas.

8. The serial arrangement as claimed in claim 1 , comprising plies.

9. The serial arrangement as claimed in claim 1 , the serial arrangement having a thickness of 150 to 600 μm.

10. The serial arrangement as claimed in claim 1 , wherein a thickness of the plies is, independently of one another, 100 to 200 μm.

11. The serial arrangement as claimed in claim 1 , wherein the plies are constructed from polyethersulfone.

12. A filtration unit comprising a serial arrangement as claimed in claim 1 , wherein the filtration unit is a cassette, a plate module, a hollow-fiber module, a pleated cartridge or a capsule.

13. The serial arrangement as claimed in claim 12 , wherein the n plies of the serial arrangement each have a radiation resistance of 20-500 kGy such that the filtration unit is sterilizable with gamma radiation for sterile-filtration.

Assignees

• Sartorius Stedim Biotech Gmbh

Inventors

• Thom Volkmar
• Hosch Jörg
• Schneider Benjamin

Classifications

• G01N2223/507

  secondary-emission detector · CPC title

• G01N2223/418

  electron microscope · CPC title

• G01N2223/401

  image processing · CPC title

• G01N2223/07

  secondary emission · CPC title

• G01N23/2251

  using incident electron beams, e.g. scanning electron microscopy [SEM] · CPC title