Nanofiber sheet and method of producing the sheet

Patent metadata

Field	Value
Publication number	US-2016296874-A1
Application number	US-201615090952-A
Country	US
Kind code	A1
Filing date	Apr 5, 2016
Priority date	Apr 13, 2015
Publication date	Oct 13, 2016
Grant date	—

Abstract

Provided is a nanofiber sheet that has a high mechanical strength, is excellent in durability, and has a high specific surface area. The nanofiber sheet includes: a plurality of nanofibers; and a bulk portion produced by bonding of the nanofibers, in which 7×10 −3 portion/μm 2 or more of the bulk portion satisfying the following formula is contained:
0.5π X 2 ≦Y ≦5 μm 2   (1)

where X represents a diameter (μm) of each of the nanofibers and Y represents an area (μm 2 ) of an inscribed circle of the bulk portion when viewed from a surface.

First claim

What is claimed is:

1 . A nanofiber sheet comprising:
a plurality of nanofibers; and a bulk portion produced by bonding of the nanofibers, wherein 7×10 −3 portion/μm 2 or more of the bulk portion satisfying the following formula (1) is contained:
0.5π X 2 ≦Y≦ 5 μm 2   (1)

where X represents a diameter (μm) of each of the nanofibers and Y represents an area (μm 2 ) of an inscribed circle of the bulk portion when viewed from a surface.

2 . The nanofiber sheet according to claim 1 , wherein 7×10 3 portions/mm 2 or more of the bulk portion satisfying the formula (1) is contained.

3 . The nanofiber sheet according to claim 1 , wherein 7×10 5 portions/cm 2 or more of the bulk portion satisfying the formula (1) is contained.

4 . The nanofiber sheet according to claim 1 , wherein a diameter of a pore formed between the nanofibers is 5 μm or less.

5 . The nanofiber sheet according to claim 1 , wherein the diameter of each of the nanofibers is 1.78 μm or less.

6 . The nanofiber sheet according to claim 1 , wherein the diameter of each of the nanofibers is from 50 nm or more to 1.78 μm or less.

7 . The nanofiber sheet according to claim 1 , wherein an average presence ratio of the nanofibers on the surface is from 10% or more to 60% or less.

8 . The nanofiber sheet according to claim 1 , wherein the nanofibers are each formed of a thermoplastic resin.

9 . The nanofiber sheet according to claim 1 , wherein the bonding is performed by fusion.

10 . The nanofiber sheet according to claim 1 , wherein the nanofiber sheet has a thickness of from 1 μm or more to 1 mm or less.

11 . A dust-collecting filter for capturing a particle, comprising the nanofiber sheet of claim 1 .

12 . A container comprising:
a vent hole; and a dust-collecting filter mounted to the vent hole, wherein the dust-collecting filter comprises the dust-collecting filter of claim 11 .

13 . A method of producing the nanofiber sheet of claim 1 , the method comprising:
a nanofiber sheet precursor-forming step of entangling a plurality of nanofibers with each other to form a nanofiber sheet precursor; and a heating step of heating the nanofiber sheet precursor.

14 . The method of producing the nanofiber sheet according to claim 13 , wherein the nanofibers each contain an organic resin material and an organic low-molecular weight compound having chemical reactivity.

15 . The method of producing the nanofiber sheet according to claim 13 , wherein the heating step comprises heating the nanofiber sheet precursor under an unpressurized condition.

Assignees

• Canon Kk

Inventors

• Yasufuku Kaori
• Hino Tetsuo
• Takashima Kenji
• Yamauchi Kazuhiro

Classifications

• B01D46/546 Primary

  using nano- or microfibres · CPC title

• B01D39/163

  sintered or bonded · CPC title

• B01D2239/025

  comprising nanofibres · CPC title

• B01D39/1623

  of synthetic origin · CPC title

• B01D46/0001

  Making filtering elements · CPC title