U.S. patent application number 14/247052 was filed with the patent office on 2014-11-27 for nonwoven fabric having improved air permeability and manufacturing method thereof.
The applicant listed for this patent is TORAY ADVANCED MATERIALS KOREA INC.. Invention is credited to Dong Wook Kim, Seo Jin Park, Je Deuk Yoon.
Application Number | 20140349539 14/247052 |
Document ID | / |
Family ID | 51935660 |
Filed Date | 2014-11-27 |
United States Patent
Application |
20140349539 |
Kind Code |
A1 |
Park; Seo Jin ; et
al. |
November 27, 2014 |
NONWOVEN FABRIC HAVING IMPROVED AIR PERMEABILITY AND MANUFACTURING
METHOD THEREOF
Abstract
A nonwoven fabric having improved air permeability and
manufacturing method thereof are presented. The nonwoven fabric has
improved air permeability and is formed with long fiber nonwoven
fabric of single or multi layer, wherein the long fiber nonwoven
fabric is produced by spinning polytrimethylene terephthalate
having viscosity of 0.8 to 1.2 and polyethylene terephthalate
having viscosity of 0.6 to 0.8 to sheath/core shape with using each
spinneret pack which can spin filaments having different denier
from each other and arranged in parallel with each other, and then
heat pressing with free-embossing or embossing pattern to bind the
filaments. The nonwoven fabric has excellent air permeability,
softness and resistance, which are required for nonwoven fabric
sheets used for various purposes as well as their economical
production.
Inventors: |
Park; Seo Jin;
(Kyungsangbuk-do, KR) ; Kim; Dong Wook;
(Kyungsangbuk-do, KR) ; Yoon; Je Deuk;
(Kyungsangbuk-do, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TORAY ADVANCED MATERIALS KOREA INC. |
Kyungsangbuk-do |
|
KR |
|
|
Family ID: |
51935660 |
Appl. No.: |
14/247052 |
Filed: |
April 7, 2014 |
Current U.S.
Class: |
442/334 ;
264/175; 428/219; 442/364 |
Current CPC
Class: |
D04H 3/011 20130101;
D01F 8/14 20130101; D04H 3/147 20130101; D10B 2331/04 20130101;
Y10T 442/608 20150401; Y10T 442/641 20150401 |
Class at
Publication: |
442/334 ;
442/364; 428/219; 264/175 |
International
Class: |
D04H 1/435 20060101
D04H001/435; D01D 5/34 20060101 D01D005/34 |
Foreign Application Data
Date |
Code |
Application Number |
May 21, 2013 |
KR |
10-2013-0057058 |
Claims
1. The nonwoven fabric having improved air permeability which is
formed with long fiber nonwoven fabric of single or multi layer,
wherein the long fiber nonwoven fabric is produced by spinning
polytrimethylene terephthalate having viscosity of 0.8 to 1.2 and
polyethylene terephthalate having viscosity of 0.6 to 0.8 to
sheath/core shape with using each spinneret pack which can spin
filaments having different denier each other and is arranged in
parallel with each other, and then heat pressing with
free-embossing or embossing pattern to bind the filaments.
2. The nonwoven fabric of claim 1, wherein the component ratio of
polytrimethylene terephthalate and polyethylene terephthalate
constituting the said nonwoven fabric is polytrimethylene
terephthalate of 10 to 50% by weight with respect to total
weight.
3. The nonwoven fabric of claim 1, wherein a basic weight of the
said nonwoven fabric is 40 to 100 g/m.sup.2.
4. The nonwoven fabric of claim 1, wherein the denier of filament
consisting of the said nonwoven fabric is at least 2 to maximum 12
deniers.
5. The nonwoven fabric of claim 1, wherein the air permeability of
the said nonwoven fabric is above 200 ccs.
6. The method for producing nonwoven fabric having improved air
permeability, the method comprising the steps of: drying polyester
having intrinsic viscosity of 0.6 to 0.8 and melting point of
260.degree. C. and polytrimethylene terephthalate having viscosity
of intrinsic viscosity of 0.8 to 1.2 and melting point of
225.degree. C. in each dryer to moisture contents of below 100 ppm,
and crystallizing and then providing it with an extruder; spinning
to sheath/core shape with using each spinneret pack which can spin
filaments having different denier each other and is arranged in
parallel with each other, wherein a filament is formed such that
the spun polytrimethylene terephthalate is to 10-50% by weight with
respect to total weight; cooling the filament with cooled air, and
consolidating it to prevent welding among the filament; elongating
and dispersing the filament by crashing it to an impinging plate
with certain velocity and angle to form a web; stacking the
prepared filament uniformly on the moving conveyer belt
successively to form a web by using a suction device at below; and
thermally bonding the said stacked filament web by using the
calendar which has the upper roll set at temperature of
180-210.degree. C. and the lower roll set at temperature of
188-208.degree. C., and nip pressure of 30-100 kg/cm, and whose
bonding rate is 10-30%.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a nonwoven fabric having
improved air permeability and manufacturing method thereof, and
more particularly to a nonwoven fabric having improved air
permeability, in which the nonwoven fabric has excellent air
permeability while maintaining a former physical property of the
prior nonwoven fabric made of poly trimethyleneterephthalate which
has proper durability and softness to be required as an
agricultural sheet that can control growth of weeds by covering a
soil being planting with the corps, and can be useful as
agricultural sheet being capable of produced economically, but has
a drawback that its air permeability is unsatisfied, and the method
for manufacturing the nonwoven fabric having improved air
permeability.
[0003] 2. Description of the Prior Art
[0004] It is common method to defoliate the weeds by spraying
herbicide or to root up it with manual labor as weed-proofing or
weeding. However, the method of using herbicide is not preferable
since it contaminates the soil or kills a microorganism at the soil
which will be beneficial on the growth of plants, so that it can be
result in devastation of the soil. Therefore, to solve such
conventional problem, the nonwoven fabric has been used to inhibit
growth of the weed by inhibiting photosynthesis. Particularly, with
covering the soil of agricultural land planted with various crops
with nonwoven fabric, while suppressing the growth of weeds, the
air is permeated and the soil is warmed so that the growth of crops
can be facilitated. Therefore, the sheet which is configured to fit
the above object is widely used in agriculture. As such nonwoven
fabric for agriculture, a polyolefin-based, especially a
polypropylene-based spunbond nonwoven fabric considering the sides
of economy as a raw material has been proposed and has been used.
More specifically, the said agricultural nonwoven fabric, for
example, nonwoven fabric which is constructed by using a synthetic
fiber filament yarn made of a polypropylene resin is provided which
one side of the nonwoven fabric is partially thermocompression
bonding embossing process or a non-woven fabric is produced with
free embossing.
[0005] For example, Korean patent early publication 2002-36636
describes, with the title of "nonwoven fabric for agriculture",
nonwoven fabric which synthetic fiber filament yarn of 2-3 denier
is arranged with the density of 55.about.65 g/m.sup.2 smoothly, and
then heat-pressed with a roller press to be embossed on one or both
sides. These nonwoven fabrics for agriculture have a relatively
good mechanical properties and its handling is easy. Also, these
nonwoven fabrics have effects that the contact area with air
becomes large by concave-convex parts of embossing so that the
permeation of air is seamlessly. However, these nonwoven fabric
thicken not to achieve an optimal air flow, and to increase the
shielding degree of light, so that the corps take the rootlet into
these nonwoven fabric due to misconception as soil and then the
corps is withered when dry whether. Therefore, it is necessary a
solution for this problem and various methods have been proposed to
solve it. Such as the pre-mentioned description, the approach for
improving the nonwoven fabric for agriculture relates, for example
physical properties of nonwoven fabric, since the conventionally
proposed nonwoven fabric for agriculture has drawback that its
thick is excess and an air flow is not smooth, and a content of
moisture is also excess so that there is a problem that it is
difficult to achieve the original object as an inhibition of growth
of weed.
[0006] But, the conventional nonwoven fabric for agriculture has a
drawback that its strength and resistance is insufficient to use as
an agricultural usage, although the conventional nonwoven fabric
for agriculture has economical advantage since the polypropylene
made of it can be produced at low cost.
[0007] On the other hand, as those having good resistance,
polytrimethylene terephthalate (PTT) had been provided with the
nonwoven fabric and synthetic fibers of various kinds. For example,
Korean Patent Application No. 2002-0049047 describes a preparing
method of polytrimethylene terephthalate staple fiber which
comprises a step of (a) supplying polytrimethylene terephthalate,
(b) spinning melted polytrimethylene terephthalate at a temperature
of 245-285.degree. C. to a filament, (c) quick quenching the
filament, (d) extending the quenched filament, (e) winding the
extended filament with 8 to 30 winding orders/inches (3 to 12
winding orders/cm) by using a mechanical winder, (f) relaxing the
winded filament at a temperature of 50-120.degree. C., and (g)
cutting the relaxed filament with a staple fiber of a length of 0.2
to 6 inches (about 0.5 to 15 cm). Also, Korean Patent Application
No. 2003-0070138 describes a polyester-based latent-crimping
conjugated fiber and method for preparing the same. Japanese patent
publication No. 2001-146671 describes a long fiber nonwoven fabric,
Japanese patent publication No. 2003-306863 describes a polyester
filament nonwoven fabric and a separation membrane using the same,
and Japanese patent publication No. 2002-180366 describes a
filament nonwoven fabric having excellent formability.
[0008] But, the prior art such as the said one never describes and
suggests for a nonwoven fabric and producing method thereof which
has a physical property suitable for the nonwoven fabric for
agriculture while it has air permeability above a desired level as
an economical nonwoven fabric by using PTT. Therefore, it is
acutely needed to provide for a nonwoven fabric having air
permeability above a desired level, while it keeps a physical
property of PPT nonwoven fabric according to the prior art.
SUMMARY OF THE INVENTION
[0009] Accordingly, the present invention has been made in view of
the problems occurring in the prior art, and it is the main purpose
of the present invention to provide a nonwoven fabric having
excellent air permeability as well as soft property and proper
resistance of the prior PPT nonwoven fabric and being capable of
produced economically.
[0010] Another object of the present invention is to provide a
production method which can solve the above-described problems
occurring in the prior art, and thus can more easily produce
nonwoven fabric having the said excellent property.
[0011] Still another object of the present invention is to achieve
other objects which can be easily conceived by a person skilled in
the art from the above-described clear objects and the description
of the specification of the present invention.
[0012] As the result of investigation for method improvable air
permeability with keeping soft property and resistance of the prior
PPT nonwoven fabric excellently, the said object of the present
invention can be achieved by producing PPT nonwoven fabric with
using a general spinneret mixed with a spinneret for coarse denier
and then by optimizing a procedure condition.
[0013] To achieve the above objects, in one aspect, the present
invention provides nonwoven fabric having improved air permeability
which is formed with long fiber nonwoven fabric of single or multi
layer, wherein the long fiber nonwoven fabric is produced by
spinning polytrimethylene terephthalate having viscosity of 0.8 to
1.2 and polyethylene terephthalate having viscosity of 0.6 to 0.8
to sheath/core shape with using each spinneret pack which can spin
filaments having different denier each other and is arranged in
parallel with each other, and then heat pressing with
free-embossing or embossing pattern to bind the filaments.
[0014] In a preferred embodiment of the present invention, the
component ratio of polytrimethylene terephthalate and polyethylene
terephthalate constituting the said nonwoven fabric is
polytrimethylene terephthalate of 10 to 50% by weight with respect
to total weight.
[0015] In a preferred embodiment of the present invention, a basic
weight of the said nonwoven fabric is 40 to 100 g/m.sup.2.
[0016] In a preferred embodiment of the present invention, the
denier of filament consisting of the said nonwoven fabric is at
least 2 to maximum 12 deniers.
[0017] In a preferred embodiment of the present invention, the air
permeability of the said nonwoven fabric is above 200 ccs.
[0018] In another aspect, the present invention provides a method
for producing nonwoven fabric having improved air permeability, the
method comprising the steps of:
[0019] drying polyester having intrinsic viscosity of 0.6 to 0.8
and melting point of 260.degree. C. and polytrimethylene
terephthalate having viscosity of intrinsic viscosity of 0.8 to 1.2
and melting point of 225.degree. C. in each dryer to moisture
contents of below 100 ppm, and crystallizing and then providing it
with an extruder;
[0020] spinning to sheath/core shape with using each spinneret pack
which can spin filaments having different denier each other and is
arranged in parallel with each other, wherein a filament is formed
such that the spun polytrimethylene terephthalate is to 10-50% by
weight with respect to total weight;
[0021] cooling the filament with cooled air, and consolidating it
to prevent welding among the filament;
[0022] elongating and dispersing the filament by crashing it to an
impinging plate with certain velocity and angle to form a web;
[0023] stacking the prepared filament uniformly on the moving
conveyer belt successively to form a web by using a suction device
at below; and
[0024] thermally bonding the said stacked filament web by using the
calendar which has the upper roll set at temperature of
180-210.degree. C. and the lower roll set at temperature of
188-208.degree. C., and nip pressure of 30-100 kg/cm, and whose
bonding rate is 10-30%.
[0025] Being constituting as the above, the nonwoven fabric having
improved air permeability and the method for producing thereof
according to the present invention is constituted mainly
polytrimethylene terephthalate and additionally polyethylene
terephthalate, and produced by spun with a filament of different
denier after mixing the said component, so that the said problem at
prior art can be solved to provide a nonwoven fabric having
excellent air permeability as well as soft property and proper
resistance which is required for the nonwoven fabric sheet of
various usage and to make it possible to produce it
economically.
DETAILED DESCRIPTION OF THE INVENTION
[0026] Hereinafter, the present invention will be described in
further detail with reference to preferred embodiments. It is to be
understood, however, that the scope of the present invention is not
limited to these embodiments.
[0027] The PTT nonwoven fabric having improved air permeability
according to the present invention may be constructed with single
layer or multi layer structure of spunbonded nonwoven fabric sheet
and/or meltblown nonwoven fabric sheet and is constructed by
heat-pressing nonfabric tissue under certain pressure and certain
temperature.
[0028] The said PTT nonwoven fabric having improved air
permeability of the present invention is preferably formed with
long fiber nonwoven fabric of single or multi layer, wherein the
long fiber nonwoven fabric is produced by spinning polytrimethylene
terephthalate having viscosity of 0.8 to 1.2 and polyethylene
terephthalate having viscosity of 0.6 to 0.8 to sheath/core shape
with using each spinneret pack which can spin filaments having
different denier each other and is arranged in parallel with each
other, and then heat pressing with free-embossing or embossing
pattern to bind the filaments.
[0029] According to a preferred embodiment of the present
invention, the component ratio of polytrimethylene terephthalate
and polyethylene terephthalate constituting the nonwoven fabric
according to the present invention is polytrimethylene
terephthalate of 10 to 50% by weight with respect to total weight.
In case of being weight rate of the said polytrimethylene
terephthalate below 10% by weight, a soft property of the nonwoven
fabric is not sufficient so that workability becomes wrong at using
the product. In contrary, in case of being weight rate of the said
polytrimethylene terephthalate exceed 50% by weight, it is not
preferable since the strength is declined and the cost for
production is increased.
[0030] In a preferred embodiment of the present invention, a basic
weight of the said nonwoven fabric is preferably 40 to 100
g/m.sup.2.
[0031] In a preferred embodiment of the present invention, the
denier of filament consisting of the said nonwoven fabric is
preferably at least 2 to maximum 12 deniers, and the air
permeability of the said nonwoven fabric is preferably above 200
ccs.
[0032] According to a different preferred embodiment of the present
invention, the fabric constituting the said nonwoven fabric may
preferably comprise the UV stabilizer of 6.0-9.0 parts by weight
which contains Hindered amine light stabilizer of 0.1-1.5 parts by
weight based on the fabric 100 parts by weight, to increase a
weatherproof. In case of being the added amount of UV stabilizer
below 0.1 parts by weight with respect to total PPT or PPT and PET
resin, an effect of weatherproof is insufficient, and in case of
being the added amount of UV stabilizer exceed 1.5 parts by weight,
it is not preferable since the workability is poor such that
pressure increases and yarn cutting occurs, and the cost for
production is increased.
[0033] According to yet another preferred embodiment of the present
invention, it is preferable to dry polyester having intrinsic
viscosity of 0.6 to 0.8 and melting point of 260.degree. C. and
polytrimethylene terephthalate having viscosity of intrinsic
viscosity of 0.8 to 1.2 and melting point of 225.degree. C. in each
dryer to moisture contents of below 100 ppm, and to crystallize and
then provide it with an extruder, and to spine to sheath/core shape
with using each spinneret pack which can spin filaments having
different denier, each other and is arranged in parallel with each
other. If the said spinneret pack which can spin filaments having
different denier each other is arranged in a random pattern, it is
difficult to make a producible product due to excessive variation
of air permeability between parts even though the total air
permeability of nonwoven fabric may become good. If the said
spinneret pack is arranged in a alternation pattern, there is a
drawback that it is impossible to form a web because a web shape
formed by filaments of thin denier is different from a web shape
formed by filaments of thick denier.
[0034] According to a preferred embodiment of the present
invention, a method for producing nonwoven fabric having improved
air permeability according to the present invention comprises the
steps of drying polyester having intrinsic viscosity of 0.6 to 0.8
and melting point of 260.degree. C. and polytrimethylene
terephthalate having viscosity of intrinsic viscosity of 0.8 to 1.2
and melting point of 225.degree. C. in each dryer to moisture
contents of below 100 ppm, and crystallizing and then providing it
with an extruder; spinning to sheath/core shape with using each
spinneret pack which can spin filaments having different denier
each other and is arranged in parallel with each other, wherein a
filament is formed such that the spun polytrimethylene
terephthalate is to 10-50% by weight with respect to total weight;
cooling the filament with cooled air, and consolidating it to
prevent welding among the filament; elongating and dispersing the
filament by crashing it to an impinging plate with certain velocity
and angle to form a web; stacking the prepared filament uniformly
on the moving conveyer belt successively to form a web by using a
suction device at below; and thermally bonding the said stacked
filament web by using the calendar which has the upper roll set at
temperature of 180-210.degree. C. and the lower roll set at
temperature of 188-208.degree. C., and nip pressure of 30-100
kg/cm, and whose bonding rate is 10-30%.
[0035] Hereinafter, the present invention will be described in
detail with reference to the following examples, but the scope of
the present invention is not limited to those examples.
EXAMPLE 1
[0036] Polyester having intrinsic viscosity of 0.65 and melting
point of 260.degree. C. and polytrimethylene terephthalate having
viscosity of intrinsic viscosity of 1.02 and melting point of
225.degree. C. were dried in each dryer to moisture contents of
below 100 ppm respectively, and crystallized and then provided with
each extruder which temperature of each zone was set at 280.degree.
C. and 260.degree. C. respectively. And it were supplied to each
spinneret pack of sheath/core shape through each supplying pump,
wherein the said packs were consisted of a pack having 52 spinneret
holes of diameter of 0.28-0.60 mm and a pack having 240 spinneret
holes and were arranged in parallel with each other. Wherein a
filament was formed such that the spun polytrimethylene
terephthalate was to 20% by weight with respect to total weight,
and two kinds of polyester was spun with 285 g per minute to form a
filament. The filament was cooled with cold air from a quenching
chamber, and consolidated it to prevent welding among the filament.
And then the cooled filament was elongated through an ejector of
air pressure of 3.5 kg/cm.sup.2 to give a property as a filament.
To form a web, the filament was dispersed by crashing it to an
impinging plate with certain velocity and angle and stacked the
said filament uniformly on the moving conveyer belt successively by
using a suction device disposed at below of conveyer belt. Here,
the velocity of conveyer belt was controlled to 22m per minute. To
thermally bond the said web, the calendar was used which has the
upper roll set at temperature of 200.degree. C. and the lower roll
set at temperature of 198.degree. C., and nip pressure of 60 kg/cm,
and whose bonding rate was 20%. The nonwoven fabric manufactured in
this manner was measured for its properties as following
experimental example, and the measurement results were shown in
Table 1.
EXAMPLE 2
[0037] The nonwoven fabrics were manufactured using the same
procedure as Example 1 above in the same condition as Example 1
except that polytrimethylene terephthalate was input to 50% by
weight with respect to total weight. The nonwoven fabric
manufactured in this manner was measured for its properties, and
the measurement results were shown in Table 1.
COMPARATIVE EXAMPLE 1
[0038] The nonwoven fabrics were manufactured using the same
procedure as Example 1 above in the same condition as Example 1
except that polytrimethylene terephthalate was input to 30% by
weight with respect to total weight. The nonwoven fabric
manufactured in this manner was measured for its properties, and
the measurement results were shown in Table 1.
COMPARATIVE EXAMPLE 2
[0039] The nonwoven fabrics were manufactured using the same
procedure as Example 1 above in the same condition as Example 1
except that a pack having 52 spinneret holes and a pack having 240
spinneret holes were arranged in alternation pattern. The nonwoven
fabric manufactured in this manner was measured for its properties,
and the measurement results were shown in Table 1.
EXPERIMENTAL EXAMPLE
[0040] The nonwoven fabrics manufactured in the manner of Examples
and Comparative examples were measured for its properties as
followings:
[0041] (1) weight per unit area (weight: g/m.sup.2): it was
measured according to the method of ASTM D 3776-1985.
[0042] (2) tensile strength: the maximum load was obtained
according to the method of ASTM D 1682-64 using the tensile
strength and extensometer device (Instron), under condition of
sample piece width of 5 cm, its interval of 7.5 cm and tensile
velocity of 300 mm/min.
[0043] (3) tensile extension: the extension degree was obtained
when being maximum extension according to the above method (2).
[0044] (4) air permeability: the amount of air which flows after
passing through a certain area of the nonwoven fabrics vertically
was measured by using an orifice (circular sample piece grasping
device) which can test an area of 38 cm.sup.2 by the method of KS K
0570.
[0045] (5) thickness: it was measured by using the dial gauge.
TABLE-US-00001 TABLE 1 Compar- Compar- ative ative Item Unit Exp. 1
Exp. 2 Exp. 1 Exp. 2 Total weight gsm 80 80 80 80 PTT contents % 80
50 30 80 PET contents % 20 50 70 20 Arrangement parallel parallel
parallel alter- shape of packs nation Temperature of .degree. C.
200 200 200 200 upper calendar Temperature of .degree. C. 198 198
198 198 lower calendar Strength (MD) kgf/5 cm 28.3 22.8 40.9 --
Strength (CD) kgf/5 cm 14.5 12.1 25.7 -- Extension (MD) % 48.2 57.6
12.4 -- Extension (CD) % 45.6 55.7 20.3 -- Thickness .mu.m 0.31
0.34 0.35 -- Air ccs 253 211 142 -- permeability Spun property good
good good spun and web impossible formability
[0046] Although the preferred embodiments of the present invention
have been described for illustrative purposes, those skilled in the
art will appreciate that various modifications, additions and
substitutions are possible, without departing from the scope and
spirit of the invention as disclosed in the accompanied claims.
* * * * *