NONWOVEN FABRIC AND PROCESS FOR PRODUCING THE SAME

• US 20080272520A1
• Filed: 07/07/2008
• Published: 11/06/2008
• Est. Priority Date: 03/31/2003
• Status: Active Grant

• Current Assignee: Teijin Limited
• Original Assignee: Teijin Limited
• Inventors: Miyoshi, Takanori, Komura, Shinya, Minematsu, Hiroyoshi, Sumi, Yoshihiko
• Granted Patent: US 8,636,942 B2
• Time in Patent Office: Days
• US Class Current: 264/465
• CPC Class Codes: D01D 5/0038 the fibre formed by solvent evaporation, i.e. dry electro-spinning
• CPC Class Codes: D01D 5/247 Discontinuous hollow structure or microporous structure
• CPC Class Codes: D01D 5/253 with a non-circular cross section; Spinnerette packs therefor D01D5/38 takes precedence
• CPC Class Codes: D01F 1/08 for forming hollow filaments
• CPC Class Codes: D01F 6/625 derived from hydroxy-carboxylic acids, e.g. lactones
• CPC Class Codes: D04H 1/43838 Ultrafine fibres, e.g. microfibres
• CPC Class Codes: D04H 1/43912 fibres with noncircular cross-sections
• CPC Class Codes: D04H 1/43916 microcellular fibres, e.g. porous or foamed fibres
• CPC Class Codes: D04H 3/02 characterised by the method of forming fleeces or layers, e.g. reorientation of yarns or filaments
• CPC Class Codes: Y10T 442/608 Including strand or fiber material which is of specific structural definition
• CPC Class Codes: Y10T 442/614 Strand or fiber material specified as having microdimensions [i.e., microfiber]

Abstract

A process for production of a nonwoven fabric, which comprises a step wherein a thermoplastic polymer is dissolved in a mixed solvent composed of a volatile good solvent and a volatile poor solvent, a step wherein the resulting solution is spun by an electrospinning method and a step wherein a nonwoven fabric accumulated on a collecting sheet is obtained, is employed to provide a nonwoven fabric having a surface area sufficiently large as a matrix for cell culturing in the field of regenerative medicine, with large gaps between filaments and a low apparent density suitable for cell culturing.

Claims

1-12. -12. (canceled)

13. A process for production of a nonwoven fabric, which comprises a step wherein a thermoplastic polymer is dissolved in a mixed solvent composed of a volatile good solvent and a volatile poor solvent, a step wherein the resulting solution is spun by an electrospinning method and a step wherein a nonwoven fabric accumulated on a collecting sheet is obtained, which process yields a nonwoven fabric with a mean fiber size of 0.1-20 μ

m, wherein any given lateral cross-section of said filaments is irregular, and a mean apparent density in the range of 10-95 kg/m³.

14. A process for production of a nonwoven fabric according to claim 13, wherein the ratio of the volatile poor solvent and volatile good solvent in said mixed solvent is in the range of (23:

77) to (40;

60), based on weight.

15. A process for production of a nonwoven fabric according to claim 13, wherein the volatile good solvent is a halogen-containing hydrocarbon.

16. A process for production of a nonwoven fabric according to claim 13, wherein the volatile poor solvent is a lower alcohol.

17. A process for production of a nonwoven fabric according to claim 16, wherein the lower alcohol is ethanol.