U.S. patent application number 16/315985 was filed with the patent office on 2020-06-11 for nanofiber structure constituted of polyhydroxyalkanoic acid, and non-woven fabric.
This patent application is currently assigned to FUENCE CO., LTD.. The applicant listed for this patent is FUENCE CO., LTD.. Invention is credited to Kozo INOUE, Sudesh K. KUMAR, Kazuya NITTA.
Application Number | 20200181818 16/315985 |
Document ID | / |
Family ID | 60577689 |
Filed Date | 2020-06-11 |
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United States Patent
Application |
20200181818 |
Kind Code |
A1 |
KUMAR; Sudesh K. ; et
al. |
June 11, 2020 |
NANOFIBER STRUCTURE CONSTITUTED OF POLYHYDROXYALKANOIC ACID, AND
NON-WOVEN FABRIC
Abstract
The biodegradability of a nanofiber film (a nanofiber structure)
produced in example 1 by microorganisms or the like when the
nanofiber film is allowed to leave in soil is examined. FIG. 4(a)
shows a photograph of the nanofiber film immediately after the
nanofiber film is placed in soil. FIG. 4(b) shows a photograph of
the nanofiber film (a) that is allowed to leave as it for 12 days.
As is obvious from the comparison between these photographs, a
polyhydroxyalkanoic acid nanofiber film can be degraded in soil
remarkably rapidly. Therefore, PHA can be produced from a
plant-derived resource occurring in nature, can be degraded by
microorganisms in soil to return to nature, and can be used as a
resource material which can overcome the disadvantages of the
conventional PP non-woven fabrics (e.g., the generation of CO.sub.2
upon incineration) and which can be used permanently, thereby
enabling the production of a novel non-woven fabric.
Inventors: |
KUMAR; Sudesh K.; (Penang,
MY) ; INOUE; Kozo; (Tokyo, JP) ; NITTA;
Kazuya; (Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
FUENCE CO., LTD. |
Tokyo |
|
JP |
|
|
Assignee: |
FUENCE CO., LTD.
Tokyo
JP
|
Family ID: |
60577689 |
Appl. No.: |
16/315985 |
Filed: |
June 7, 2016 |
PCT Filed: |
June 7, 2016 |
PCT NO: |
PCT/JP2016/066904 |
371 Date: |
January 7, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
D10B 2401/021 20130101;
D04H 1/4382 20130101; D04H 1/435 20130101; D01F 6/62 20130101; D10B
2401/022 20130101; D10B 2401/12 20130101 |
International
Class: |
D04H 1/435 20060101
D04H001/435; D04H 1/4382 20060101 D04H001/4382; D01F 6/62 20060101
D01F006/62 |
Claims
1. A nanofiber structure formed of polyhydroxyalkanoic acid.
2. The nanofiber structure according to claim 1, wherein the
polyhydroxyalkanoic acid includes polyhydroxybutylate as a main
component.
3. The nanofiber structure according to claim 1, wherein the
nanofiber structure has a fiber diameter of 1 .mu.m or less.
4. The nanofiber structure according to claim 1, wherein the
nanofiber structure is degraded by microorganisms in soil in a
natural environment.
5. The nanofiber structure according to claim 1, wherein the
nanofiber structure has a porosity of 50% or more.
6. The nanofiber structure according to claim 1, wherein the
nanofiber structure has water repellency, and a contact angle of
pure water to a surface of the nanofiber structure is 100.degree.
or more.
7. The nanofiber structure according to claim 1, wherein the
nanofiber structure has oil absorbency.
8. The nanofiber structure according to claim 1, wherein the
nanofiber structure has organic solvent absorbency.
9. The nanofiber structure according to claim 1, wherein the
surface of the nanofiber structure has hydrophilicity by surface
modification by a plasma treatment, a corona discharge, electron
beam irradiation, or laser irradiation, or the like.
10. The nanofiber structure according to claim 1, further
comprising an adsorbent material.
11. The nanofiber structure according to claim 1, wherein the
nanofiber structure is partially fused to have a film shape.
Description
TECHNICAL FIELD
[0001] The present invention relates to a nanofiber structure
constituted of polyhydroxyalkanoic acid, and a non-woven fabric,
and more particularly, to a nanofiber structure constituted of
polyhydroxyalkanoic acid having oil or organic solvent absorbency
simultaneously with a property of being rapidly degraded by
microorganisms and the like in the natural environment, and a
non-woven fabric.
BACKGROUND ART
[0002] Usage of a non-woven fabric manufactured from various
organic polymers has recently been expanded, and is used for
various uses in various industries from textile industries
(interlining field) to sanitary materials, medical materials,
automobile interior materials, industrial materials (filter,
wiping, etc.), civil engineering materials, agricultural materials,
geotextiles (fiber sheet for soil reinforcement), environmental
industries, and the like. In the future also, production of the
non-woven fabric is predicted to continuously expand every year.
Among the non-woven fabrics, polypropylene (PP) non-woven fabric
has a high growth rate, and a growth rate of nearly 10% is
expected.
[0003] However, growth of the non-woven fabric industry made of the
organic polymer has a big problem at the same time. Since the
organic polymer which is a main component of the non-woven fabric
is purified and synthesized from petroleum resources, problems of
depletion of future resources and treatment of used products occur.
The treatment of used products (wastes) is treating the used
products by pelletizing and the like to recycle the used product as
resources, incinerating the used products, burying and disposing
the used products, and the like. The products to be recycled as
resources are in a very small amount, and in the present situation,
the used products are largely incinerated or buried. Since
incineration discharges CO.sub.2 in a large amount, influence on
global warming is an important problem. In addition, in the case of
landfills, since resins derived from petroleum are very difficult
to degrade, the resins remain in the ground almost permanently such
that the global environment is polluted forever.
[0004] One of the solutions to these problems is to use a
biodegradable polymer in a raw material of the non-woven fabric.
Resin products using a biodegradable organic polymer such as
polylactic acid or polyhydroxyalkanoic acid have been already
developed. Although the polyhydroxyalkanoic acid has been developed
for a long time by domestic and foreign companies, costs of
production and purification by microorganisms delay
practicality.
[0005] However, Kaneka Corporation recently reported that
commercialization of a resin product manufactured from
polyhydroxyalkanoic acid is in progress. However, since the company
aims to develop a so called, resin product, development in the
non-woven fabric field as described above has not been made.
[0006] As non patent literatures of the related art of the
above-described biodegradable polymer, for example, there are
"Conclusion of a blanket agreement for product development of
"Kaneka Biopolymer AONILEX" with Biotech of Germany
(http://www.kaneka.co.jp/service/news/150217)" (Non Patent
Literature 1), "Certification of development of plant-derived
biodegradable resin manufacture technology by Japan Science and
Technology Agency (http://www.kaneka.co.jp/service/news/140710-2)"
(Non Patent Literature 2), "Manufacture of biodegradable plastic by
microorganisms (Microbiol. Cult. Coll. 29(1):25-29, 2013)" (Non
Patent Literature 3), and "The world's first full development of
100% plant-derived biopolymer having softness and thermal
resistance (http://www.kaneka.co.jp/service/news/n090206.html)"
(Non patent Literature 4).
CITATION LIST
Non Patent Literature
[0007] Non Patent Literature 1: A website of "Conclusion of a
blanket agreement for product development of "Kaneka Biopolymer
AONILEX" with Biotech of Germany":
http://www.kaneka.co.jp/service/news/150217 [0008] Non Patent
Literature 2: A website of "Certification of development of
plant-derived biodegradable resin manufacture technology by Japan
Science and Technology Agency":
http://www.kaneka.co.jp/service/news/140710-2 [0009] Non Patent
Literature 3: "Manufacture of biodegradable plastic by
microorganisms (Microbiol. Cult. Coll. 29(1): 25-29, 2013)" written
by Tetsuya Fujiki [0010] Non Patent Literature 4: A website of "The
world's first full development of 100% plant-derived biopolymer
having softness and thermal resistance":
http://www.kaneka.co.jp/service/news/n090206.html
SUMMARY OF INVENTION
Technical Problem
[0011] According to a market report, it is predicted that a market
size of a non-woven fabric, in particular a polypropylene (PP)
non-woven fabric is to increase by about 8% every year in the
future, and is to reach about 30 billion US dollars in 2020. The
main uses thereof are sanitary goods such as diapers (for infants
or the elderly), geotextiles, environmental pollutant treatments,
automobile industries, furniture, and the like, and it is said that
the uses are caused by growth in Asia-Pacific region which has a
high population growth rate.
[0012] In addition, it is predicted that the production quantity of
non-woven fabric is to increase from 5.94 million in 2013 to 9.97
million in 2020. As long as petroleum resource-derived PP is used,
CO.sub.2 emissions are increased in contrast to a global agreement
to prevent global warming, and thus, effective measures are needed.
The inventors of the present application established a technique
for inexpensively carrying out a production and purification
process of biodegradable polyhydroxyalkanoic acid (PHA) by
microorganisms, and conducted an applied study for various
uses.
[0013] Further, the inventors of the present application repeated
study and speculation for solving the problems, and as a result,
found a technique of making biodegradable polyhydroxyalkanoic acid
into nanofiber and using the nanofiber as a nanofiber structure
(such as non-woven fabric) having various characteristics.
[0014] An object of the present invention is to provide a nanofiber
structure constituted of polyhydroxyalkanoic acid. Another object
of the present invention is to develop the nanofiber structure as
the non-woven fabric to solve the problems of the current synthetic
resin non-woven fabric.
Solution to Problem
[0015] To solve the above problems, a nanofiber structure according
to a first invention is a nanofiber structure constituted of
polyhydroxyalkanoic acid (one or plural types).
[0016] In addition, a nanofiber structure according to a second
invention is characterized in that the polyhydroxyalkanoic acid
includes polyhydroxybutylate as a main component.
[0017] The structure includes polyhydroxybutylate as a main
component, and preferably, is blended with another
polyhydroxyalkanoic acid (for example, a copolymer with
polyhydroxyhexanoic acid).
[0018] In addition, a nanofiber structure according to a third
invention is characterized by having a fiber diameter of 1 .mu.m or
less.
[0019] In addition, a nanofiber structure according to a fourth
invention has a characteristic of being degraded by microorganisms
in the soil in the natural environment.
[0020] In addition, a nanofiber structure according to a fifth
invention is characterized by having a porosity of 50% or more.
[0021] The structure has high air permeability and a light weight
by having higher porosity.
[0022] In addition, a nanofiber structure according to a sixth
invention is characterized by having water repellency, and a
contact angle of pure water to a surface of the nanofiber structure
is 100.degree. or more.
[0023] In addition, a nanofiber structure according to a seventh
invention is characterized by having oil absorbency.
[0024] In addition, a nanofiber structure according to an eighth
invention is characterized by having organic solvent
absorbency.
[0025] In addition, a nanofiber structure according to a ninth
invention is characterized in that the surface of the nanofiber
structure has hydrophilicity by surface modification by a plasma
treatment, a corona discharge, electron beam irradiation, or laser
irradiation.
[0026] The nanofiber structure may be used in sanitary products and
the like by having hydrophilicity by surface modification.
[0027] In addition, a nanofiber structure according to a tenth
invention is characterized by including an adsorbent material.
[0028] An adsorbent is for example, activated carbon, zeolite, or
the like, and included in a nanofiber and on a surface of the
nanofiber.
[0029] In addition, a nanofiber structure according to an eleventh
invention is characterized in that the nanofiber structure is
partially fused to have a film shape.
[0030] As described above, the solution to the problem of the
present invention is described as a nanofiber structure, however,
the present invention may also be realized by a method of
manufacturing a nanofiber structure which substantially corresponds
to the solution, and it should be understood that the scope of the
present invention also includes the method.
Advantageous Effects of Invention
[0031] According to the present invention, it is possible to
provide a nanofiber structure (film) having characteristics of
being flexible and having oil or organic solvent absorbency,
simultaneously with being rapidly degraded by microorganisms in the
natural environment so as not to cause an increase of CO.sub.2 gas.
The nanofiber structure may be used as non-woven fabric in various
industries.
BRIEF DESCRIPTION OF DRAWINGS
[0032] FIG. 1 is a conceptual diagram representing a basic
configuration of an electrospray deposition device.
[0033] FIG. 2 is a SEM photograph of a nanofiber structure
manufactured in Example 1 as a material.
[0034] FIG. 3 is an electron microscope photograph (SEM photograph)
of a PHA nanofiber structure shown in FIG. 2.
[0035] FIG. 4 is a drawing representing biodegradability of a
nanofiber film of Example 1.
[0036] FIG. 5 is a drawing representing water repellency of the
nanofiber film of Example 1.
[0037] FIG. 6 is a drawing representing oil-water separability and
oil absorbency of the nanofiber film of Example 1.
[0038] FIG. 7 is a drawing representing organic solvent absorbency
of the nanofiber film of Example 1.
[0039] FIG. 8 is an electron microscope photograph (SEM photograph)
of a nanofiber film (nanofiber structure) which is partially fused
to have a film shape.
[0040] FIG. 9 is an electron microscope photograph (SEM photograph)
of a nanofiber film including fine particles as an adsorbent
material.
DESCRIPTION OF EMBODIMENTS
[0041] Hereinafter, embodiments of the present invention will be
described in detail with reference to the drawings.
[0042] A polyhydroxyalkanoic acid used in an exemplary embodiment
of the present invention is a sample prepared by microbial culture
and purification method, the patentee of which is University of
Science-Malaysia to which one of the inventors of the present
application belongs. Nanofiber may be manufactured from the sample
by an electrospray deposition (ESD) method, a melt blown method, or
other method of manufacturing nanofiber, however, an ESD method or
a melt blown method is preferred.
<Electrospray Deposition Method>
[0043] Before the embodiments of the present invention are
described, the principle of an electrospray deposition method (ESD
method) used in the embodiment of the present invention and an
electrospray deposition device (ESD: electrospray device) allowing
the electrospray deposition method to be carried out will be
described.
<Electrospray Deposition Device>
[0044] FIG. 1 is a conceptual diagram representing a basic
configuration of an electrospray deposition device. As shown in the
drawing, a container (CNT) contains a sample solution (SL). The
sample solution (SL) is, for example, an organic polymer solution,
a polymer solution, or the like. In the present embodiment, the
sample solution is a polyhydroxyalkanoic acid solution, that is, a
polyhydroxyalkanoic acid solution.
[0045] Although the ESD method is a very complicated physical
phenomenon and all of the processes are not explained, the ESD
method is generally considered as being the following phenomenon.
The sample solution is contained in a thin capillary shaped nozzle
(NZL), and voltage of thousands to tens of thousands of volts is
applied to a target substrate (TS) (counter electrode) opposing
thereto. At a capillary tip, a strong electric field occurs by an
electric field concentration effect, and microdroplets with charge
on a liquid surface gather to form a cone (also called Taylor
cone). In addition, the sample solution from the tip destroys
surface tension to become a jet. The jet is strongly charged and
becomes spray by a repulsion of electrostatic force (coulomb
explosion). The droplets formed by spray are very small so that the
solvent is evaporated and dried within a short time to become fine
nanoparticles or nanofiber. Of course, the solvent may be deposited
in a wet state which is not evaporated or dried. The charged fine
nanoparticles or nanofiber having a small diameter is pulled to the
target substrate (TS) functioning as a counter electrode by
electrostatic force. A pattern to be deposited may be controlled by
an insulator mask or an auxiliary electrode (not shown). The sample
is not limited to a solution, and a dispersion solution is
fine.
[0046] In addition, preferably, the sample solution in the
container (CNT) applies extrusion pressure toward the nozzle (NZL)
by an air pressure syringe pump, plunger, or the like (ejection
means, not shown). The extrusion pressure is imparted by for
example, a stepping motor and a screw feed mechanism (not shown).
The sample solution (SL) to which the extrusion pressure is applied
has increased internal pressure in the container (CNT) so as to be
discharged from the tip of nozzle (NZL). As described above, by
installing an adjustment mechanism (the stepping motor and the
screw feed mechanism) adjusting the speed of ejecting the sample
solution, it is possible to adjust the ejection speed
appropriately.
[0047] The nozzle (NZL) is made of metal, and positive voltage is
supplied from a high voltage power supply (HPS) through a conductor
wire (WL). The negative side of the high voltage power supply (HPS)
is connected to the target substrate (TS) (substrate to be a
counter electrode). By applying voltage from the high voltage power
supply (HPS), positive voltage is applied via the nozzle (NZL) to
the sample solution (SL) so that the solution is positively
charged. The polarity of the voltage applied to the sample solution
(SL) may be negative.
[0048] In addition, when the nanofiber structure is manufactured,
it is preferred that non-woven fabric is placed on the target
substrate (TS), and the nanofiber structure is deposited on the
non-woven fabric. In addition, various conditions such as voltage
level, concentration of the sample solution, the kind of
polyhydroxyalkanoic acid as a sample, the kind of solvent, and the
like are adjusted to manufacture the nanofiber structure.
[0049] The sprayed material becomes fiber or droplets, and repeats
division during scattering by repulsion due to charging to form
nanofiber or nanoparticles. Since the sprayed material has a large
surface area in a nano size, when the sprayed material comes into
contact with the substrate, it is in an almost dried state. The
shape or size may be changed depending on the spray conditions, and
for example, when a polymer solution is used, thick nanofiber is
formed with a high molecular weight and a high concentration, and
thin nanofiber or nanoparticles are formed with a low molecular
weight and a low concentration. Besides, various conditions such as
voltage or a distance between the nozzle and the substrate and
ambient temperature or humidity have an influence thereon. In the
present embodiment, various kinds of solvent-soluble
polyhydroxyalkanoic acid are used as a sample to manufacture
nanofiber under various conditions, and confirmation of water
repellency, air permeability, hydrophilicity, and the like were
carried out by the method described in the Example. As the
electrospray deposition device, another type of ESD device as well
as the above-described device can be used. In particular, for mass
production, a method using air current described in Japanese Patent
No. 5491189, developed by the applicants, is preferred.
[0050] In addition, during mass production, a non-woven
manufacturing device using a melt blown method is also preferred,
in addition to the ESD device.
<Example 1> Nanofiberization by ESD Method
[0051] FIG. 2 is a photograph of a polyhydroxyalkanoic acid
nanofiber film (PHA nanofiber structure) manufactured by an ESD
device of FIG. 1. As a sample solution, a chloroform solution
including 10% by weight of polyhydroxyalkanoic acid (PHA) was used.
In the manufacturing process, an ESD device (ES-4000, manufactured
by HUENS Co., LTD.) was used to spray the solution at voltage of 50
kV and a flow rate of 10 .mu.l/min. A thickness of nanofiber film
shown in the drawing was 20 .mu.m. This nanofiber film is very
thin, is a free-standing film in spite of the small fiber diameter,
may be deposited on other non-woven fabric or film or incorporated
into another member or instrument, and is very useful.
[0052] FIG. 3 is an electron microscope photograph (SEM photograph)
of the PHA nanofiber structure shown in FIG. 2. The magnification
of the photograph is 1000 times. In addition, an average diameter
of the nanofiber was about 1 .mu.m. As shown in the drawing, it is
observed that a porous film in which fiber is entangled in a
mesh-like pattern is formed, which has high porosity and forms a
light structure. The PHA nanofiber structure may be used as a
filter using the porous property. The nanofiber diameter, porosity,
density, and the like are varied by changing various solution
compositions or spray conditions according to the purpose, and are
controllable.
<Example 2> Biodegradability
[0053] FIG. 4 is a drawing representing biodegradability of the
nanofiber film of Example 1. The biodegradability of the nanofiber
film (nanofiber structure) obtained in Example 1 by microorganisms
and the like was studied by leaving the nanofiber film in soil.
FIG. 4(a) is a photograph immediately after placing the nanofiber
film in soil. FIG. 4(b) is a photograph after leaving the nanofiber
film in FIG. 4(a) for 12 days as it is. As seen from the comparison
of these photographs, the polyhydroxyalkanoic acid nanofiber film
degrades quite rapidly in soil. As such, since PHA can be produced
by microbial fermentation from a plant raw material of nature, and
degraded by microorganisms in soil to be returned to nature, the
nanofiber film may be used as a resource which does not increase
gas causing global warming and may be permanently used.
<Example 3> Water Repellency
[0054] FIG. 5 is a drawing representing water repellency of the
nanofiber film of Example 1. FIG. 5 is a photograph immediately
after adding pure water dropwise by a pipette on the nanofiber film
obtained in Example 1. The dropped pure water (WD) remained on the
film as a droplet, as shown in the photograph. As a result of
visually measuring the contact angle, a value of 87.5-130.5.degree.
was obtained by measurement with 10 droplets, and the average was
113.7.degree.. The nanofiber film had water repellency.
<Example 4> Oil-Water Separability and Oil Absorbency
[0055] FIG. 6 is a drawing representing oil-water separability and
oil absorbency of the nanofiber film of Example 1. The nanofiber
film obtained in Example 1 was added to a container having a
methylene blue solution and salad oil therein by pouring it from
the above. FIG. 6(a) is a photograph before the nanofiber film was
added to the container. The aqueous methylene blue solution and
salad oil are mixed in a separated state. FIG. 6(b) is a photograph
1 minute after the nanofiber film was added to the container. As
shown in FIG. 6(b), it is observed that the nanofiber film floated
on the aqueous methylene blue solution so that only the salad oil
(OL) remained in the nanofiber film. FIG. 6(c) is a photograph 10
minutes after the nanofiber film was added. As shown in the
photograph of FIG. 6(c), it is observed that the nanofiber film
absorbed only the salad oil within 10 minutes, and absorbed all of
the salad oil in the film, at the end. In addition, the nanofiber
film did not absorb the aqueous methylene blue solution at all.
That is, it was found that polyhydroxyalkanoic acid nanofiber film
has a function of separating water and oil simultaneously with a
function of selectively absorbing only oil.
<Example 5> Organic Solvent Absorbency
[0056] FIG. 7 is a drawing representing organic solvent absorbency
of the nanofiber film of Example 1. FIG. 7(a) is a photograph
before the nanofiber film obtained in Example 1 was added to the
container having an aqueous methylene blue solution (MB) and hexane
(HX). Here, the aqueous methylene blue solution (MB) and hexane
(HX) were separated into two layers. FIG. 7(b) is a photograph 10
minutes after the nanofiber film was added to the container. As
shown in the photograph of the drawing, it is observed that hexane
(HX) was all absorbed in the nanofiber film within 10 minutes.
Since the amount of the aqueous methylene blue solution (MB) was
not changed, it was found that the nanofiber film selectively
absorbed only hexane of the organic solvent and did not absorb
water. That is, it was found that the nanofiber film represents
excellent organic solvent absorbency.
<Example 6> Nanofiber Film (Nanofiber Structure) Partially
Having a Film Shape
[0057] FIG. 8 is an electron microscope photograph (SEM photograph)
of the nanofiber film (nanofiber structure) in which the nanofiber
film is partially fused to have a film shape. As shown in the
drawing, it is observed that there is a film shape in the front
side and a nanofiber film in the inside. This film shaped part is
useful for improving strength of the film itself.
<Example 7> Adsorbent Material-Containing Nanofiber Film
[0058] FIG. 9 is an electron microscope photograph (SEM photograph)
of the nanofiber film including fine particles as an adsorbent
material. As shown in the drawing, it is observed that activated
carbon fine particles AC1 and AC2 as the adsorbent material are
entangled with the nanofiber FBR1 and FBR2 and maintained. In
addition, the activated carbon fine particles may be in the
nanofiber or on the surface of the nanofiber. The adsorbent
material effectively absorbs the components dissolved in the
organic solvent (impurities or components to be separated) passing
between the nanofiber films. As an adsorbent, for example,
activated carbon, zeolite, or the like can be selected depending on
the use.
[0059] Finally, the advantages of the nanofiber film (nanofiber
structure and the like) according to each Example of the present
invention are indicated. Biodegradable polyhydroxyalkanoic acid
(PHA) which is a raw material of the nanofiber film can be produced
using a plant component of nature as a raw material. It is possible
to suppress an increase in carbon dioxide gas by using the
biodegradable polyhydroxyalkanoic acid to manufacture the nanofiber
structure and widely use it for a non-woven fabric.
[0060] The polypropylene non-woven fabric which is the conventional
product is flexible and strong and has good adhesion with other
materials, and thus, has been used for various uses. In particular,
the polypropylene non-woven fabric has been used as an oil
adsorbent material since the polypropylene non-woven fabric absorbs
oil. It was found by an experiment that the polyhydroxyalkanoic
acid or polyhydroxybutyric acid which is a material of the
nanofiber structure according to an exemplary embodiment of the
present invention absorbs an organic solvent and toxic organic
compounds soluble in the solvent as well as oil.
[0061] For example, when ocean, river, lake, groundwater, or the
like contaminated with an organic solvent and an organic compound
dissolved in the organic solvent was passed through the nanofiber
structure according to an exemplary embodiment of the present
invention, using these characteristics, contaminated goods can be
filtered and absorbed to make clean water.
[0062] As described above, the nanofiber structure (nanofiber film)
according to the present invention is expected to be used for
various purposes mainly as a non-woven fabric.
REFERENCE SIGNS LIST
[0063] CNT: Container [0064] HPS: High voltage power supply [0065]
NZL: Nozzle [0066] SL: Sample solution [0067] TS: Target substrate
[0068] ESD: Electrospray deposition device [0069] WL: Wire
* * * * *
References