U.S. patent application number 12/812269 was filed with the patent office on 2010-11-04 for fabric and clothes using the same.
This patent application is currently assigned to Toray Industries, Inc.. Invention is credited to Kenji Akizuki, Kazuya Fujita, Takaji Yasuda.
Application Number | 20100279572 12/812269 |
Document ID | / |
Family ID | 40853037 |
Filed Date | 2010-11-04 |
United States Patent
Application |
20100279572 |
Kind Code |
A1 |
Fujita; Kazuya ; et
al. |
November 4, 2010 |
FABRIC AND CLOTHES USING THE SAME
Abstract
A fabric comprises conductive yarns inserted each in a warp
direction and a weft direction and disposed in a lattice at
intervals, wherein at least either one of the conductive yarns in
the warp direction or the weft direction is inserted as a double
weave to be a float yarn on the surface that the conductive yarn
becomes a float yarn in the double weave, wherein a ratio of the
conductive yarn inserted as the double weave not covered by an
orthogonal nonconductive yarn but exposed is not less than 50% in
arithmetic average, and a ratio of the conductive yarns in the warp
direction and the weft direction intersect and contact each other
is not less than 40% in arithmetic average. Clothes comprise the
fabric, wherein the conductive yarn is inserted as the double weave
in an obverse side of the clothes.
Inventors: |
Fujita; Kazuya; (Shiga,
JP) ; Akizuki; Kenji; (Osaka, JP) ; Yasuda;
Takaji; (Ishikawa, JP) |
Correspondence
Address: |
RATNERPRESTIA
P.O. BOX 980
VALLEY FORGE
PA
19482
US
|
Assignee: |
Toray Industries, Inc.
Tokyo
JP
|
Family ID: |
40853037 |
Appl. No.: |
12/812269 |
Filed: |
December 25, 2008 |
PCT Filed: |
December 25, 2008 |
PCT NO: |
PCT/JP2008/073597 |
371 Date: |
July 9, 2010 |
Current U.S.
Class: |
442/195 ;
442/189; 442/209; 442/301 |
Current CPC
Class: |
D10B 2331/04 20130101;
D03D 15/00 20130101; Y10T 442/3114 20150401; Y10T 442/3976
20150401; D10B 2501/00 20130101; D03D 1/0058 20130101; D10B 2331/02
20130101; D10B 2101/20 20130101; D03D 15/47 20210101; Y10T 442/3228
20150401; Y10T 442/3065 20150401; D10B 2101/12 20130101; D10B
2201/02 20130101; A41D 31/26 20190201; C09K 3/16 20130101; D10B
2401/022 20130101; D03D 15/44 20210101; D10B 2201/24 20130101; D10B
2401/16 20130101 |
Class at
Publication: |
442/195 ;
442/301; 442/209; 442/189 |
International
Class: |
D03D 15/00 20060101
D03D015/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 11, 2008 |
JP |
2008-004052 |
Claims
1) A fabric comprising conductive yarns inserted each in a warp
direction and a weft direction and disposed in a lattice at
intervals, wherein at least either one of the conductive yarns in
the warp direction or the weft direction is inserted as a double
weave to be a float yarn on the surface that the conductive yarn
becomes a float yarn in the double weave, wherein a ratio of the
conductive yarn inserted as the double weave not covered by an
orthogonal nonconductive yarn but exposed is not less than 50% in
arithmetic average, and a ratio that the conductive yarns in the
warp direction and the weft direction intersect and contact each
other is not less than 40% in arithmetic average.
2) The fabric of claim 1 further comprising a base weave having a
nonconductive yarn, wherein a total yarn fineness D1 of the
conductive yarn inserted as the double weave and a total yarn
fineness D2 of the nonconductive yarn forming the base weave in the
same direction satisfy the following relationship: D1<D2.
3) The fabric of claim 1, wherein the conductive yarns disposed in
a lattice at intervals have a pitch in a range of 1 to 20 mm both
in the warp direction and the weft direction.
4) The fabric of claim 1, further comprising a surface electric
resistance (R) between two points separated by 30 cm across at
least one seam that satisfies the following formula:
R.ltoreq.1.0.times.10.sup.12.OMEGA..
5) The fabric of claim 1, wherein the conductive yarn comprises a
monofilament having a circular cross section or an irregular cross
section having a convex part, wherein a conductive component is
exposed in at least 3 places in a circumferential direction of an
outer circumferential surface and continuously in a longitudinal
direction.
6) Clothes comprised of the fabric described in claim 1, wherein
the conductive yarn is inserted as the double weave in an obverse
side of the clothes.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a U.S. National Phase Application of PCT
International Application No. PCT/JP2008/073597, filed Dec. 25,
2008, which claims priority to Japanese Patent Application No.
2008-004052, filed Jan. 11, 2008, the contents of these
applications being incorporated by reference herein in their
entirety.
TECHNICAL FIELD OF THE INVENTION
[0002] The present invention relates to a fabric having excellent
surface electroconductive and antistatic properties, and to clothes
that the fabric is sewn. Further specifically it relates to a
fabric having the surface electroconductive property over the whole
region across the seam of clothes and being excellent in
electrostatic diffuseness, and to clothes using the same.
BACKGROUND OF THE INVENTION
[0003] Conductive clothes have been conventionally used for
preventing electrostatic attraction of dust in a workshop or clean
room handling parts and chemicals to which static electricity is an
obstacle. In the conductive clothes, conductive yarns are woven
into the clothes for taking measures against static electricity.
For example, electrostatic attraction of dust is prevented by
weaving conductive yarns into the clothes at a certain interval in
a stripe or lattice and neutralizing static electricity by corona
discharge. In general, the conductive yarn is often colored black
or gray for aesthetic purposes. One example of an antistatic
clothing product in which the conductive yarn is exposed a lot in
the reverse side of clothes is described in Japanese Unexamined
Patent Publication No. 2001-73207. However, in this method, surface
electric resistance in the outer surface of clothes is high, and
efficiency of diffusing static electricity generated inside the
clothes into the outside of the clothes becomes bad.
[0004] In recent years, as demand characteristics of electrostatic
control according to IEC (International Electrotechnical
Commission) 61340-5-1, 5-2, surface electric resistance of
conductive clothes has been regulated, and surface
electroconductive property over the overall clothes may be
required. In order to enhance the electroconductive property in the
whole region of clothes, the electroconductive property across seam
is preferred, such as in the oblique direction of the cloth. In
this case, it becomes necessary or advantageous to weave conductive
yarns in a lattice to make contacts in the different directions,
and to bring conductive yarns into contact with each other in the
sewn part of clothing fabric. In the case of forming conductive
yarn as multiple wound yarn, twisted yarn or comingled yarn with
nonconductive yarn, when nonconductive yarn is disposed on the
surface of conductive yarn, electroconductive property with
conductive yarn of the other direction is not formed. That means,
to enhance the electroconductive property, a blending ratio of
conductive yarn must be increased, and an increase in cost
accompanied with this cannot be avoided.
[0005] Japanese Patent No. 3880743 describes that electroconductive
property with the conductive yarn of the other direction is
improved by covering nonconductive yarn with conductive yarn, but
there remains a problem on processing cost of covering yarn as
well.
SUMMARY OF THE INVENTION
[0006] The present invention provides a fabric exhibiting excellent
surface conductive performance in the whole direction. The present
invention also provides conductive clothes showing surface
electroconductivety overall in clothes and capable of diffusing
static electricity rapidly into air, by sewing the fabric.
[0007] The present invention provides a fabric comprising
conductive yarns inserted each in the warp direction and the weft
direction and disposed in a lattice at intervals, wherein at least
either one of the conductive yarns in the warp direction or the
weft direction is inserted as a double weave to be a float yarn on
the surface that the conductive yarn becomes a float yarn in the
double weave, wherein a ratio of the conductive yarn inserted as
the double weave not covered by an orthogonal nonconductive yarn
but exposed (exposing conductive yarn ratio in double weave part)
is not less than 50% in arithmetic average, and a ratio of the
conductive yarns in the warp direction and the weft direction
intersect and contact each other (conductive yarn intersect contact
ratio) is not less than 40% in arithmetic average.
In another embodiment of the present invention, the fabric further
comprises a base weave having a nonconductive yarn, wherein a total
yarn fineness D1 of the conductive yarn inserted as the double
weave and a total yarn fineness D2 of the nonconductive yarn
forming the base weave in the same direction satisfy the following
relationship:
D1<D2,
where D1 is the total yarn fineness of conductive yarn inserted as
the double weave (dtex), and D2 is the total yarn fineness of
nonconductive yarn forming the base weave in the same direction as
the conductive yarn inserted as the double weave (dtex)]. In a
further embodiment of the present invention, the conductive yarns
disposed in a lattice at intervals have a pitch in a range of 1 to
20 mm both in the warp direction and the weft direction. In yet
another embodiment, the fabric further comprises a surface electric
resistance (R) between two points separated by 30 cm across at
least one seam that satisfies the following formula:
R.ltoreq.1.0.times.10.sup.12.OMEGA., as measured by a method
described in IEC (International Electrotechnical Commission)
61340-5-1, 5-2 (under the environment of 23.degree. C. and 25% RH).
In still another embodiment of the present invention, the
conductive yarn comprises a monofilament having a circular cross
section or an irregular cross section having a convex part, wherein
a conductive component is exposed in at least 3 places in a
circumferential direction of an outer circumferential surface and
continuously in a longitudinal direction. The present invention
also provides clothes comprised of the fabric described above,
wherein the conductive yarn is inserted as the double weave in an
obverse side of clothes.
[0008] According to aspects of the present invention, it is
possible to obtain a fabric exhibiting excellent surface conductive
performance in the whole direction, and to obtain conductive
clothes with high surface electroconductive property in clothes
overall.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a diagram of textile weave of fabric produced in
Examples (however, the number of base yarns between conductive
yarns does not correspond for convenience.).
[0010] FIG. 2 is a cross sectional view of one example of surface
exposing type conductive yarn in an embodiment of the present
invention.
[0011] FIG. 3 is one example of piling methods of fabrics in
stitching two pieces of fabrics to measure surface electric
resistance.
[0012] FIG. 4 is a schematic diagram of measuring method of surface
electric resistance across seam.
DESCRIPTION OF NUMBER AND SYMBOL
[0013] 1: Conductive yarn incorporated in double weave [0014] 2:
Conductive yarn inserted by dobby [0015] 3: Nonconductive component
base polymer [0016] 4: Polymer part that matrix including carbon is
exposed at part of surface [0017] 5: Stitch by lock stitch sewing
machine [0018] 6: Overlapped part of cloth [0019] 7: Measuring
probe (linear distance between probes: 30 cm) [0020] 8: Flat felled
seam part [0021] 9: Surface electric resistance detector
DETAILED DESCRIPTION OF THE INVENTION
[0022] The fabric of the present invention may include only
conductive yarn just for exhibiting electrical conductivity, but in
order to exhibit electrical conductivity inexpensively, the fabric
preferably includes nonconductive yarn and conductive yarn.
[0023] As the nonconductive yarn used in the fabric of the present
invention, there are preferably used, for example, a synthetic yarn
and natural yarn, namely, a filament yarn of polyester, nylon etc.,
spun yarn, a blended yarn of staple of polyester, nylon etc. with
rayon staple, cotton yarn etc., further, an antistatic polyester
filament yarn or antistatic nylon yarn that a hydrophilic polymer
is blended or an hydrophilic group is introduced, and the like.
[0024] The conductive yarn used in the fabric of the present
invention may be a yarn containing a conductive component; for
example, it is a metal-covered yarn, a yarn composed of conductive
yarn that a nonconductive base polymer of polyester or polyamide to
be fiber base, and a conductive fine particle of carbon or metal
and metal compound etc., or a white-color conductive ceramic fine
particle etc., are contained by composite spinning; or a yarn
containing these conductive yarns. In an embodiment of the present
invention, a conductive yarn with carbon as a conductive component
is preferable from the points of durability under acid or alkali
environment and washing durability.
[0025] As a method for compounding a conductive component in yarn,
there are methods for yarn making, such as core-in-sheath, covering
and partially surface exposing types. In the case of being used as
dust-proof clothes for clean rooms of high cleanness, a covering
type conductive yarn that core fibers were covered by a conductive
component, and a partially surface exposing type yarn that a
conductive component was exposed partially at the surface may lead
to dust generation from the conductive component and contamination
of workshop; thus, core-in-sheath type yarn that a conductive
component was included inside is preferably used. On the other
hand, in a workshop where that high cleanness is not required, by
using the above-described partially surface exposing type yarn, it
is possible to obtain cloth of lower surface electric
resistance.
[0026] The partially surface exposing type yarn means a yarn where
a conductive component is exposed partially in the circumferential
direction at the cross section of single fiber composing the yarn
and the conductive component exposed is exposed continuously in the
longitudinal direction of single fiber. Above all, from the point
of lowering surface electric resistance, preferable is a conductive
yarn composed of fibers with a circular cross section shown in FIG.
2 (a) or with an irregular cross section having a convex part shown
in FIG. 2 (b), and on the outer circumferential surface of the
single fiber, a conductive component is exposed in at least 3
places in the circumferential direction and continuously in the
longitudinal direction. Additionally, in the case of an irregular
cross-section fiber, it is preferable that a conductive component
is exposed at the convex part in the circumferential direction.
[0027] Further, in another embodiment of the present invention, a
conductive yarn can be also formed by doubling, twisting or
comingling a yarn containing these conductive components and a
synthetic yarn or natural yarn.
[0028] As a configuration of conductive yarn, staple can be used.
In this case, since electric resistance between single fiber
increases, not blending with nonconductive yarn, but the conductive
yarn alone is preferably used. More preferably, a filament is used
as the conductive yarn, thereby it becomes possible to suppress the
increase of electric resistance between single fibers to the
minimum.
[0029] As the conductive yarn, for example, one with a single fiber
fineness of 1 to 10 dtex and the total yarn fineness of 10 to 150
dtex is used. The electric resistance of conductive yarn is
preferably 10.sup.9 .OMEGA./cm or less, in particular, 10.sup.8
.OMEGA./cm or less. Such electric resistance can be easily attained
by exposing a conductive component on the part of surface. Here,
electric resistance of conductive yarn means specific resistance
that under the environment of 20.degree. C. and 30% RH, electric
voltage is loaded on both ends filament-cut to 10 cm (500 V set in
this case).
[0030] The fabric of the present invention, in at least one
embodiment of the present invention, is a fabric that the
above-described conductive yarns are inserted in the warp direction
and the weft direction to be disposed in a lattice at intervals.
The conductive yarns are incorporated in one of the warp direction
and the weft direction or in both as double weave to be disposed on
(or beneath at the reverse side of) base yarn (ordinarily
nonconductive yarn) composing the base weave of the same direction.
Namely, in the double weave, the conductive yarn is exposed on the
fabric as a float yarn to be a protruded shape from the base weave.
In this way, the area of conductive yarn exposed on the fabric
surface is increased, and contact with conductive yarn in other
direction is improved, so that the neutralization and diffusion of
static electricity becomes easy. Here, when the conductive yarn is
not disposed on (or beneath) the nonconductive yarn (base yarn) of
the same direction, but disposed between nonconductive yarns of the
same direction, the conductive yarn is buried in the base yarn
(nonconductive yarn) and contact with orthogonal conductive yarn
less.
Thus, the neutralization and diffusion of static electricity
becomes insufficient.
[0031] In an embodiment of the present invention, as described
above, conductive yarn is exposed on the fabric surface. For the
conductive yarn incorporated in the fabric as double weave, it is
preferable that an exposing conductive yarn ratio in double weave
part is not less than 50% in arithmetic average, and further
preferably not less than 70%.
[0032] Herein, an exposing conductive yarn ratio in double weave
part is a ratio of the area of, when the surface that conductive
yarn line A is inserted in double weave to be float yarn is viewed
from the upper surface, the part that the conductive yarn line A
being float yarn is not covered by the orthogonal nonconductive
yarn line but exposed relative to the total area of conductive yarn
line A inserted as double weave. Here, the total area of conductive
yarn line A inserted as double weave is a product of width of a
conductive yarn line A and length of the conductive yarn line A,
and that includes the part covered by the orthogonal other yarn
line and not exposed on the surface in said area. In the part not
covered by the orthogonal nonconductive yarn but exposed of
conductive yarn line A, the part covered by the orthogonal
conductive yarn line is included. On the other hand, the part not
becoming float yarn although it is the part of the above-described
conductive yarn line A, namely, the part not disposed on the
nonconductive yarn being base weave but disposed beside the
nonconductive yarn by rolling down is not included.
[0033] Additionally, in an embodiment of the present invention, an
exposing conductive yarn ratio per 2.54 cm (one inch) in the
longitudinal direction of conductive yarn inserted in double weave
is calculated. From the exposing conductive yarn ratios of 5 places
randomly chosen, an arithmetic average is calculated. The
arithmetic average herein is obtained by summing all values of data
and dividing which by the number of data (n number). Therefore, the
values of the exposing conductive yarn ratios at 5 places are all
summed, and the value summed up is divided by 5.
[0034] In the case that conductive yarns are incorporated in double
weave in both the warp direction and the weft direction, it becomes
possible to be a shape that conductive yarns are exposed on either
surface of front-back sides of fabric. In this case, the exposing
conductive yarn ratio in the double weave part may be calculated
each for the obverse face and reverse face by the foregoing method,
and an embodiment of the present invention, it is good enough that
in either face, the exposing conductive yarn ratio is not less than
50% in arithmetic average.
[0035] As means to achieve an exposing conductive yarn ratio of not
less than 50% in arithmetic average, it is preferable to adjust a
total fineness ratio of nonconductive yarn and conductive yarn.
Namely, in order to dispose the conductive yarn completely on the
nonconductive yarn in the double weave part (or beneath in the
reverse side), it is preferable, in an embodiment of the present
invention, that the total yarn fineness of conductive yarn D1 is
less than the total yarn fineness of nonconductive yarn forming the
base weave in the same direction D2 (D1<D2).
[0036] When the total yarn fineness of conductive yarn to be
inserted in double weave is set to be smaller than that of
nonconductive yarn being base yarn, the conductive yarn is easy to
take a position being disposed on the base yarn (nonconductive
yarn), and the delivery and receipt of electric charges is
efficiently done at the intersection of the conductive yarns to be
able to improve electroconductive property. In particular, a force
pushing down by the orthogonal other yarns is operated on the
conductive yarn in fabric, but by satisfying D1<D2, the
conductive yarn inserted in double weave tends to be disposed on
the base yarn. Hence, even when the total yarn fineness of
conductive yarn or the number of filaments is reduced, the surface
electric resistance does not deteriorate extremely, and it becomes
possible to reduce weaving costs by adopting the finer conductive
yarn.
[0037] Even when D1.gtoreq.D2, it does not bother for performance
of conductive fabric, but the cost of conductive yarn becomes more,
which will not be a preferable mode because conductive performance
of fabric becomes saturated. In the case that the total yarn
fineness of conductive yarn is large, when it is inserted in double
weave, disposing it on base yarn becomes difficult. For example,
there arise problems that the conductive yarn is disposed partially
rolling down from above the base yarn, or friction at the
conductive yarn inserting part in fabric becomes strong.
[0038] Additionally, making conductive yarn finer sometimes leads
to yield loss by yarn break in weaving; thus, it is preferable to
adopt a comingling or double-twisting conductive yarn with
nonconductive yarn as the conductive yarn. Thereby, it is possible
to adjust yarn strength and stabilize weaving performance. The
fineness ratio of conductive yarn in comingled yarn and double
twisted yarn is preferably not less than 30%, more preferably not
less than 50% for obtaining a good surface electric resistance.
[0039] By satisfying the above-described constituent, in at least
one embodiment of the present invention, it is possible to obtain a
conductive fabric where conductive yarns are more exposed on the
fabric surface. Since conductive yarns are more exposed on the
fabric surface, when the conductive fabric of the present invention
is sewn, point contact of conductive yarns between clothing fabrics
is easily done, and electroconductive property of sewn product
overall can also be more enhanced.
[0040] In another embodiment of the present invention, the method
of inserting an orthogonal conductive yarn in double weave is not
particularly limited, but it is advantageous for the ratio that
conductive yarns in the warp direction and the weft direction in
fabric intersect each other and make contacts (contact ratio of
intersecting conductive yarns) to be not less than 40% in
arithmetic average. When it is less than 40%, electroconductive
property in the oblique direction of fabric becomes insufficient,
and the electroconductive property between fabrics is not obtained
sufficiently when they are sewn. On the other hand, when it is set
to 40% or more, electroconductive property in the oblique direction
is easily obtained, and a good electroconductive property between
fabrics is obtained when they are sewn. The arithmetic average of
the contact ratio of intersecting conductive yarns is preferably
not less than 50%, and more preferably not less than 60%. For
example, in the case that conductive yarns are inserted in weft
double weave, when weft conductive yarns are disposed at intervals
in a ratio of every odd-numbered yarn and warp conductive yarns are
inserted in plain weave, the contact ratio of intersecting
conductive yarns becomes 50%, obtaining a sufficient
electroconductive property. On the other hand, when warp conductive
yarns are inserted in skipping over one yarn in the obverse side,
and 2 yarns in the reverse side, the contact ratio of intersecting
conductive yarns becomes 33%, not obtaining a sufficient
electroconductive property.
[0041] The contact ratio of intersecting conductive yarns defined
herein is a ratio of the number of intersections that conductive
yarns directly contact each other relative to the number of
intersections of orthogonal conductive yarns. Namely, in the case
that 5 conductive yarns are inserted each in the warp direction and
in the weft direction, the ratio is calculated from the number of
points where conductive yarns are intersecting and contacting in
the total 25 points of conductive yarns intersecting; for example,
when the number of points where conductive yarns are intersecting
and contacting is 15, the contact ratio of intersecting conductive
yarns is calculated to be 60%. Additionally, in at least one
embodiment of the present invention, the arithmetic average at 5
places in total randomly chosen is 40% or more.
[0042] In some embodiments of the present invention, conductive
yarns are not necessarily inserted in both the warp direction and
the weft direction in double weave, and only one of them can be
double weave. Namely, when conductive yarns are inserted either in
the warp direction or the weft direction as double weave, because
the other intersecting conductive yarn is made contact with a
conductive yarn at the intersection, electroconductive property is
ensured in the oblique direction as well.
[0043] As a method for inserting conductive yarns, other than
double weave, a mode that conductive yarn is incorporated in base
yarn has no problem. However, to satisfy the foregoing contact
ratio of intersecting conductive yarns of not less than 60%, it is
preferable to use twill or satin weave as fabric texture. In the
case of plain weave, there arises no problem when weaving design is
done for the conductive yarns inserted in double weave to be
contacted with intersecting conductive yarns. As another method,
change weave using a dobby loom is suitably used. When conductive
yarns are disposed on the fabric surface and a design is done so as
to satisfy a contact ratio of intersecting conductive yarns of not
less than 60%, a good surface electric resistance can be obtained
over the whole region of fabric.
[0044] In at least one embodiment of the present invention,
regarding the number of constraints of conductive yarn in the
double weave part by the orthogonal base yarn (nonconductive yarn),
the fewer it is, the more lowering trend the surface electric
resistance shows, but from the point of snagging performance, 6
yarns/2.54 cm or more are preferable.
[0045] In the fabric of the present invention, as described in at
least one of the embodiments above, conductive yarns are inserted
and disposed each in the warp direction and the weft direction into
a lattice at a certain interval for example. As the interval that
the conductive yarns are inserted and disposed, the narrower it is,
the better the conductive characteristic becomes. From the balance
among conductive characteristic, drape, aesthetic property,
appearance quality, cost and the like, it is preferably set for the
pitch to be about 1 to 20 mm. When the pitch is less than 1 mm, the
number of conductive yarns disposed becomes too large, it is not
preferable from the points of drape, appearance and quality, and
production cost of conductive yarn. When the pitch is more than 20
mm, it is advantageous to have more seam allowance width not so as
to increase surface electric resistance across seam, which is not
preferable from the production cost of fabric. The pitch is more
preferably about 1 to 10 mm.
[0046] According to an embodiment of the present invention as
described above, since conductive yarns are exposed a lot on the
surface composing fabric, point contact of conductive yarns between
clothing fabrics sewn is easily done. Hence, according the fabric
of the present invention, it becomes possible to satisfy IEC
(International Electrotechnical Commission) 61340-5-1, 5-2
regulation being a demand characteristic for electrostatic control.
Namely, under the temperature and humidity environment of
23.degree. C. and 25% RH, when surface electric resistance is
measured at an applied voltage of 10 V or 100 V between two points
separated by 30 cm in the oblique direction across at least one
seam, it is possible to obtain fabric or clothes of not more than
1.0.times.10.sup.12.OMEGA. in the surface electric resistance.
Here, the applied voltage is chosen according to the surface
resistance of test piece, 10 V in the region of not more than
10.sup.5.OMEGA., and 100 V in the region of not less than
10.sup.6.OMEGA. are chosen.
[0047] In order to achieve this demand characteristic, when the
fabric of the present invention is measured in the same way as IEC
(International Electrotechnical Commission) 61340-5-1, 5-2 except
for the change being not across seam, the surface electric
resistance R of R.ltoreq.1.0.times.10.sup.12.OMEGA. is preferable.
From the consideration of electrostatic diffusiveness, R in such
measurement is further preferably not more than
1.0.times.10.sup.10.OMEGA., and 1.0.times.10.sup.6.OMEGA. to
1.0.times.10.sup.9.OMEGA. is most preferable. In such range, static
electricity is diffused efficiently and quickly, spark electric
shock from a charged body can be prevented, and it becomes possible
to be used suitably as antistatic working clothes and dust-proof
clothing applications.
[0048] In the case that the surface electric resistance between two
points across seam is set to be not more than
1.0.times.10.sup.12.OMEGA., it is advantageous to bring conductive
yarns between cloths into contact in stitching. In this time, the
more the number of contact points of conductive yarns in seam
allowance increases, the more the surface electric resistance
between cloths lowers. In embodiments of the present invention
where conductive yarns are disposed on base yarns using double
weave, this is a very advantageous design upon thinking about
stitching of conductive yarn contacts, and the surface electric
resistance between two points across seam can easily satisfy the
above-described range.
[0049] Regarding the fabric of the present invention described
above, when the surface that conductive yarns are inserted in
double weave to be float yarn is used in the obverse side of
clothes, the clothes show excellent antistatic property even if
static electricity is generated in any part, since fabric and
clothes overall are stably electroconductive, corona discharge from
conductive yarns occurs or earthing is positively done.
[0050] In the case that clothes are produced using the fabric of
the present invention, stitch in sewing and seam are by no means
restricted. Any stitch can be chosen, such as lock stitch, single
chain stitch, double chain stitch and over lock. In regard to seam,
it is possible to use seam suitable for various types of
applications without limitation, such as rolled seam, flat felled
seam, safety stitch and piping.
EXAMPLES
[0051] Next, the present invention is explained specifically by
using Examples, but the present invention is by no means limited to
these Examples. Additionally, various measuring methods in the
present invention are as follows.
[0052] Exposing Conductive Yarn Ratio in Double Weave Part:
[0053] The woven surface that conductive yarns are inserted as
double weave to be float yarn is set to a state capable of
observing 2.54 cm (one inch) in the longitudinal direction of the
conductive yarn on the same screen using a microscope. By
monitoring the conductive yarn part in the double weave part of
this surface, in this screen, there is calculated a ratio of the
area of the part not covered by the orthogonal nonconductive yarn
line (conductive yarn exposed) to the whole area of conductive yarn
of 2.54 cm (one inch) length (projected area). Here, the exposing
conductive yarn ratios of the double weave part at 5 places in
total randomly chosen are calculated, and the arithmetic average is
adopted.
[0054] Contact Ratio of Intersecting Conductive Yarns:
[0055] It is calculated from the number of points where conductive
yarns are intersecting and contacting at the orthogonal
intersections of 25 points in total composed of grids of 5 warps by
5 wefts of conductive yarns. Here, the arithmetic average is
calculated from the exposing conductive yarn ratios at 5 places in
total randomly chosen.
[0056] Surface Electric Resistance of Sewn Part:
[0057] It was measured as bellow based on IEC (International
Electrotechnical Commission) 61340-5-1, 5-2 regulation.
[0058] Clothes (blouson) are produced by carrying out a
predetermined stitching by a lock stitch sewing machine.
Thereafter, on the clothes, measuring probes of a surface electric
resistance tester (Model 152AP-5P manufactured by Trek Japan Co.,
Ltd.) are mounted at an interval of 30 cm across seam between them,
and surface electric resistance is measured at an applied voltage
of 100 V between two points. In this time, the two points are taken
so that the coaxial conductive yarns of fabric specimen are not
included. This is repeated at arbitrary three places, and the
arithmetic average is calculated. FIG. 3 shows a schematic diagram
after sewing, and FIG. 4 shows a schematic diagram for measuring
surface electric resistance.
Example 1
[0059] Using two-ply yarn of polyester melt adhesive fiber (84
decitex, 36 filaments) as a warp forming base weave and polyester
false twist yarn (334 decitex, 96 filament) as a weft, and as a
warp conductive yarn and a weft conductive yarn, a conductive yarn
(84 decitex, 9 filaments) composed of surface exposing type yarn
shown in FIG. 2 was used. The weave was made as shown in FIG. 1 in
such manner that base weave was plain fabric (one-sided mat), and
the warp conductive yarns were disposed by dobby weave in a ratio
of every 24 yarns of base warps (pitch 5 mm) in skipping over 2
yarns in the obverse side, and one yarn in the reverse side. The
weave was made as shown in FIG. 1 in such manner that the weft
conductive yarns were inserted in a ratio of every 11 yarns of base
wefts in weft double weave (pitch 5 mm), and disposed on the base
weft (namely being float yarn) in skipping over 3 yarns in the
obverse side, and one yarn in the reverse side. In this way, a gray
fabric of 141 yarns/2.54 cm in warp density and 57 yarns/2.54 cm in
weft density was produced. This gray fabric was refined, dyed and
finished according to the common method to obtain a fabric of 153
yarns/2.54 cm in finish warp density and 62 yarns/2.54 cm in weft
density. The fabric obtained was sewn by a sewing machine, and the
surface electric resistance of sewn part was measured. Various data
are shown in Table 1.
Example 2
[0060] It was carried out in the same conditions as Example 1
except that only conductive yarn was changed. Namely, as the
conductive yarn, there was used a double twisted yarn (89 decitex,
18 filaments) of polyester false twist yarn (33 decitex, 12
filaments) with surface exposing type conductive yarn (56 decitex,
6 filaments). The fabric obtained was sewn by a sewing machine, and
the surface electric resistance of sewn part was measured. Various
data are shown in Table 1.
Example 3
[0061] Using two-ply yarn of polyester false twist yarn (84
decitex, 36 filaments) as a warp forming base weave and polyester
false twist yarn (334 decitex, 96 filaments) as a weft, and as a
warp conductive yarn and a weft conductive yarn, a surface exposing
type conductive yarn (84 decitex, 9 filaments) was used. The weave
was made in such manner that base weave was plain fabric (one-sided
mat), and the warp conductive yarns were disposed by dobby weave in
a ratio of every 32 yarns of base warps (pitch 5 mm) in skipping
over 3 yarns in the obverse side, and one yarn in the reverse side.
The weave was made in such manner that the weft conductive yarns
were inserted in a ratio of every 15 yarns of base wefts in weft
double weave (pitch 5 mm), and disposed on the base weft in
skipping over 6 yarns in the obverse side, and 2 yarns in the
reverse side. In this way, a gray fabric of 202 yarns/2.54 cm in
warp density and 74 yarns/2.54 cm in weft density was produced.
This gray fabric was refined, dyed and finished according to the
common method to obtain a fabric of 208 yarns/2.54 cm in finish
warp density and 85 yarns/2.54 cm in weft density. The fabric
obtained was sewn by a sewing machine, and the surface electric
resistance of sewn part was measured. Various data are shown in
Table 1.
Example 4
[0062] Using two-ply yarn of polyester false twist yarn (84
decitex, 36 filaments) as a warp forming base weave and polyester
false twist yarn (334 decitex, 96 filaments) as a weft, and as a
warp conductive yarn and a weft conductive yarn, a surface exposing
type conductive yarn (84 decitex, 9 filaments) was used. The weave
was made in such manner that base weave was plain fabric (one-sided
mat), and the warp conductive yarns were disposed by dobby weave in
a ratio of every 32 yarns of base warps (pitch 5 mm) in skipping
over 2 yarns in the obverse side, and 2 yarns in the reverse side.
The weave was made in such manner that the weft conductive yarns
were inserted in a ratio of every 15 yarns of base wefts in weft
double weave (pitch 5 mm), and disposed on the base weft in
skipping over 2 yarns in the obverse side, and 2 yarns in the
reverse side. In this way, a gray fabric of 202 yarns/2.54 cm in
warp density and 74 yarns/2.54 cm in weft density was produced.
This gray fabric was refined, dyed and finished according to the
common method to obtain a fabric of 208 yarns/2.54 cm in finish
warp density and 85 yarns/2.54 cm in weft density. The fabric
obtained was sewn by a sewing machine, and the surface electric
resistance of sewn part was measured. Various data are shown in
Table 1.
Example 5
[0063] Using two-ply yarn of polyester melt adhesive fiber (84
decitex, 36 filaments) as a warp forming base weave and polyester
false twist yarn (84 decitex, 36 filament) as a weft, and as a warp
conductive yarn and a weft conductive yarn, a conductive yarn (56
decitex, 6 filaments) composed of surface exposing type yarn was
used. The weave was made in such manner that base weave was plain
fabric (one-sided mat), and the warp conductive yarns were disposed
by dobby weave in a ratio of every 24 yarns of base warps (pitch 5
mm) in skipping over 2 yarns in the obverse side, and one yarn in
the reverse side. The weave was made in such manner that the weft
conductive yarns were inserted in a ratio of every 11 yarns of base
wefts in weft double weave (pitch 5 mm), and disposed on the base
weft in skipping over 3 yarns in the obverse side, and one yarn in
the reverse side. In this way, a gray fabric of 141 yarns/2.54 cm
in warp density and 152 yarns/2.54 cm in weft density was produced.
This gray fabric was refined, dyed and finished according to the
common method to obtain a fabric of 150 yarns/2.54 cm in finish
warp density and 159 yarns/2.54 cm in weft density. The fabric
obtained was sewn by a sewing machine, and the surface electric
resistance of sewn part was measured. Various data are shown in
Table 1.
Example 6
[0064] Using two-ply yarn of polyester melt adhesive fiber (84
decitex, 36 filaments) as a warp forming base weave and polyester
false twist yarn (84 decitex, 36 filament) as a weft, and as a warp
conductive yarn and a weft conductive yarn, a conductive yarn (56
decitex, 6 filaments) composed of surface exposing type yarn was
used. The weave was made in such manner that base weave was plain
fabric (one-sided mat), and the warp conductive yarns were disposed
by dobby weave in a ratio of every 72 yarns of base warps (pitch 15
mm) in skipping over 2 yarns in the obverse side, and one yarn in
the reverse side. The weave was made in such manner that the weft
conductive yarns were inserted in a ratio of every 33 yarns of base
wefts in weft double weave (pitch 15 mm), and disposed on the base
weft in skipping over 3 yarns in the obverse side, and one yarn in
the reverse side. In this way, a gray fabric of 140 yarns/2.54 cm
in warp density and 153 yarns/2.54 cm in weft density was produced.
This gray fabric was refined, dyed and finished according to the
common method to obtain a fabric of 150 yarns/2.54 cm in finish
warp density and 160 yarns/2.54 cm in weft density. The fabric
obtained was sewn by a sewing machine, and the surface electric
resistance of sewn part was measured. Various data are shown in
Table 1.
Example 7
[0065] Using two-ply yarn of polyester melt adhesive fiber (84
decitex, 36 filaments) as a warp forming base weave and polyester
false twist yarn (84 decitex, 36 filament) as a weft, and as a warp
conductive yarn and a weft conductive yarn, a conductive yarn (56
decitex, 6 filaments) composed of surface exposing type yarn was
used. The weave was made in such manner that base weave was plain
fabric (one-sided mat), and the warp conductive yarns were disposed
by dobby weave in a ratio of every 120 yarns of base warps (pitch
25 mm) in skipping over 2 yarns in the obverse side, and one yarn
in the reverse side. The weave was made in such manner that the
weft conductive yarns were inserted in a ratio of every 55 yarns of
base wefts in weft double weave (pitch 25 mm), and disposed on the
base weft in skipping over 3 yarns in the obverse side, and one
yarn in the reverse side. In this way, a gray fabric of 141
yarns/2.54 cm in warp density and 152 yarns/2.54 cm in weft density
was produced. This gray fabric was refined, dyed and finished
according to the common method to obtain a fabric of 149 yarns/2.54
cm in finish warp density and 162 yarns/2.54 cm in weft density.
The fabric obtained was sewn by a sewing machine, and the surface
electric resistance of sewn part was measured. Various data are
shown in Table 1.
Example 8
[0066] It was carried out in the same conditions as Example 1
except that only conductive yarn was changed. Namely, as the
conductive yarn, there was used a double twisted yarn (140 decitex,
45 filaments) of polyester false twist yarn (56 decitex, 36
filaments) with surface exposing type conductive yarn (84 decitex,
9 filaments). The fabric obtained was sewn by a sewing machine, and
the surface electric resistance of sewn part was measured. Various
data are shown in Table 1.
Comparative Example 1
[0067] Using polyester false twist yarn (167 decitex, 48 filaments)
as a warp forming base weave and polyester false twist yarn (334
decitex, 96 filaments) as a weft, and as a warp conductive yarn and
a weft conductive yarn, there was used a double twisted yarn (89
decitex, 18 filaments) of polyester false twist yarn (33 decitex,
12 filaments) with surface exposing type conductive yarn (56
decitex, 6 filaments). The weave was made in such manner that base
weave was plain fabric, and the warp conductive yarns were disposed
by dobby weave in a ratio of every 16 yarns of base warps (pitch 5
mm) in skipping over 2 yarns in the obverse side, and one yarn in
the reverse side. The weave was made in such manner that the weft
conductive yarns were disposed also by dobby weave in a ratio of
every 10 yarns of base wefts (pitch 5 mm) in skipping over 2 yarns
in the obverse side, and one yarn in the reverse side. In this way,
a gray fabric of 85 yarns/2.54 cm in warp density and 54 yarns/2.54
cm in weft density was produced. This gray fabric was refined, dyed
and finished according to the common method to obtain a fabric of
92 yarns/2.54 cm in finish warp density and 58 yarns/2.54 cm in
weft density. The fabric obtained was sewn by a sewing machine, and
the surface electric resistance of sewn part was measured. Various
data are shown in Table 1.
Comparative Example 2
[0068] Using two-ply yarn of polyester false twist yarn (84
decitex, 36 filaments) as a warp forming base weave and polyester
false twist yarn (334 decitex, 96 filaments) as a weft, and as a
warp conductive yarn and a weft conductive yarn, a conductive yarn
(84 decitex, 9 filaments) composed of surface exposing type yarn
was used. The weave was made in such manner that base weave was
plain fabric (one-sided mat), and the warp conductive yarns were
disposed by dobby weave in a ratio of every 32 yarns of base warps
(pitch 5 mm) in skipping over one yarn in the obverse side, and
three yarns in the reverse side. The weave was made in such manner
that the weft conductive yarns were inserted in a ratio of every 15
yarns of base wefts in weft double weave (pitch 5 mm), and disposed
on the base weft in skipping over 6 yarns in the obverse side, and
2 yarns in the reverse side. In this way, a gray fabric of 202
yarns/2.54 cm in warp density and 74 yarns/2.54 cm in weft density
was produced. This gray fabric was refined, dyed and finished
according to the common method to obtain a fabric of 208 yarns/2.54
cm in finish warp density and 85 yarns/2.54 cm in weft density. The
fabric obtained was sewn by a sewing machine, and the surface
electric resistance of sewn part was measured. Various data are
shown in Table 1.
Comparative Example 3
[0069] Using two-ply yarn of polyester false twist yarn (84
decitex, 36 filaments) as a warp forming base weave and polyester
false twist yarn (84 decitex, 96 filaments) as a weft, and as a
warp conductive yarn and a weft conductive yarn, there was used a
double twisted yarn (89 decitex, 18 filaments) of polyester false
twist yarn (33 decitex, 12 filaments) with surface exposing type
conductive yarn (56 decitex, 6 filaments). The weave was made in
such manner that base weave was plain fabric (one-sided mat), and
the warp conductive yarns were disposed by dobby weave in a ratio
of every 32 yarns of base warps (pitch 5 mm) in skipping over 2
yarns in the obverse side, and one yarn in the reverse side. The
weave was made in such manner that the weft conductive yarns were
inserted in a ratio of every 28 yarns of base wefts in weft double
weave (pitch 5 mm), and disposed on the base weft in skipping over
6 yarns in the obverse side, and 2 yarns in the reverse side. In
this way, a gray fabric of 202 yarns/2.54 cm in warp density and
152 yarns/2.54 cm in weft density was produced. This gray fabric
was refined, dyed and finished according to the common method to
obtain a fabric of 212 yarns/2.54 cm in finish warp density and 164
yarns/2.54 cm in weft density.
[0070] However, regarding the conductive yarn inserted in weft
double weave, the total fineness is larger than the total fineness
of weft base yarn (D1>D2), thus, an embodiment that the
conductive yarn was buried partially in the base yarn (embodiment
of not being float yarn) was formed, and the exposing conductive
yarn ratio was 30%. The fabric obtained was sewn by a sewing
machine, and the surface electric resistance of sewn part was
measured. Various data are shown in Table 1.
Comparative Example 4
[0071] Using two-ply yarn of polyester melt adhesive fiber (84
decitex, 36 filaments) as a warp forming base weave and polyester
false twist yarn (84 decitex, 36 filaments) as a weft, and as a
warp conductive yarn and a weft conductive yarn, there was used a
double twisted yarn (84 decitex, 39 filaments) of polyester false
twist yarn (56 decitex, 36 filaments) with surface exposing type
conductive yarn (28 decitex, 3 filaments). The weave was made in
such manner that base weave was plain fabric (one-sided mat), and
the warp conductive yarns were disposed by dobby weave in a ratio
of every 24 yarns of base warps (pitch 5 mm) in skipping over 2
yarns in the obverse side, and one yarn in the reverse side. The
weave was made in such manner that the weft conductive yarns were
inserted in a ratio of every 11 yarns of base wefts in weft double
weave (pitch 5 mm), and disposed on the base weft in skipping over
3 yarns in the obverse side, and one yarn in the reverse side. In
this way, a gray fabric of 141 yarns/2.54 cm in warp density and
152 yarns/2.54 cm in weft density was produced. This gray fabric
was refined, dyed and finished according to the common method to
obtain a fabric of 150 yarns/2.54 cm in finish warp density and 158
yarns/2.54 cm in weft density. The fabric obtained was sewn by a
sewing machine, and the surface electric resistance of sewn part
was measured. Various data are shown in Table 1.
TABLE-US-00001 TABLE 1 Exposing conductive Contact raito of Total
finess of double weave part (dtex) yarn ratio in intersecting
Surface electric D1 (Conductive D2 (Nonconductive double weave part
conductive yarn resistance (.OMEGA.) yarn) yarn) (arithmetic
average: %) (arithmetic average: %) Example 1 3.7 .times. 10.sup.7
84 334 76 67 Example 2 1.1 .times. 10.sup.8 89 334 76 67 Example 3
6.8 .times. 10.sup.7 84 334 76 75 Example 4 8.7 .times. 10.sup.8 84
334 52 50 Example 5 2.3 .times. 10.sup.8 56 84 76 67 Example 6 1.5
.times. 10.sup.10 56 84 76 67 Example 7 3.9 .times. 10.sup.11 56 84
76 67 Example 8 6.2 .times. 10.sup.11 140 334 76 67 Comparative 1.0
.times. 10.sup.13 No double weave No double weave No double weave
50 example 1 Comparative 2.3 .times. 10.sup.12 84 334 76 25 example
2 Comparative 5.3 .times. 10.sup.12 89 84 30 67 example 3
Comparative 1.6 .times. 10.sup.12 84 84 48 67 example 4
[0072] The fabric of the present invention can provide a sewn
product excellent in durability of antistatic property. As a
result, such fabric can be suitably used in clothes such as
uniform, cap, dust-proof clothing, and other application for
prevention of static charge.
* * * * *