Note: Descriptions are shown in the official language in which they were submitted.
CA 02947826 2016-11-08
Use of Continuous Filament Non-Woven Fabrics for Preventing Down
Leakage from Down-Filled Textile Products
The invention relates to the use of a nonwoven fabric made of continuous
filaments for
preventing down leakage from a down-filled textile product, whereby the
continuous
filaments have a titer of less than 0.15 dtex. The invention relates also to
down-filled textile
products and the processes for their manufacture.
Background Art
Down, also called under feathers, are feathers with short rachis and soft
barbs. Down is used
in textile products such as bedding, jackets or sleeping bags, as fillers for
thermal insulation.
The down feathers are thereby enclosed by and contained in envelopes made of
sheet form
textile materials. Down filled products must be down leakage proof during
their intended use.
That means that the down cannot penetrate or even exit the envelope. Since
rachis of down
feathers are pointy and hard, the envelopes must have a high closeness. Thick
and strong cloth
is especially suited as envelopes. Cloth consists of mutually interwoven warp
and weft yarns.
Down rachis, which are pointy but are in general significantly larger than
cloth yarns and
textile loops, cannot penetrate woven fabric, since the fibres are not
sufficiently displaceable
relative to one another. The down tightness of woven fabric can be tested with
a standardized
process according to DIN 12132-1.
Contrary to woven fabric, textile nonwoven materials are not suited as
envelopes for the
filling with down. Even thick textile nonwoven materials are relatively easily
penetrated by
down. Since the fibres of common nonwoven materials are unorganized and
therefore
displaceable relative to one another, rachis can readily penetrate them. Down
tightness of
nonwoven materials can be achieved by solidifying them over a large area
either thermally or
chemically. The fibres are then bound to one another, similar to in a woven
fabric and no
longer freely placeable relative to one another. Such a large area
solidification is however not
acceptable for textile uses, since it leads to disadvantageous properties such
as low softness
and elasticity, low porosity and associated low permeability for air and
humidity. Therefore,
woven fabric is generally used for down fill in the art since it was assumed
in the art that
commonly known nonwoven materials are not suited for filling with down, no
standardized
CA 02947826 2016-11-08
process for the measurement of down tightness for nonwoven materials exists
similar to the
DIN 12132-1 for woven fabric.
It would however be desirable to make nonwoven materials also suitable for
such
applications, since nonwoven materials have many advantageous properties which
distinguish
them from woven fabric, such as high softness, elasticity, stability, porosity
and high air and
moisture permeability, as well as good availability and workability.
It is therefore suggested in the art to use nonwoven materials for the storage
of down only as a
component in laminates. For example, JP 2008/303480A suggests the use of a
laminate
material made of a woven fabric and a nonwoven material. JP 2006/291421A
discloses down
tight laminates which include thermally solidified nonwoven materials. It is
however
disadvantageous that components are included which are actually not ideal
nonwoven
materials. Moreover, laminates are relatively difficult to manufacture in
particular because the
components need to be glued together or solidly connected with one another in
some other
manner.
The utility model DE 203 10 279 U 1 describes envelopes made of microfibre
nonwoven
material with good air permeability which form a protection against allergens
and mites. The
envelopes have advantageous mechanical properties characteristic for nonwoven
materials,
for example with respect to washability and stability. It is also alleged in
the disclosure that
the microfibre nonwoven material is down-proof. No evidence is provided. The
microfibre
fleece according to the exemplary embodiment of DE 203 10 279 U 1 is a real
nonwoven
material which was neither thermally solidified over a large area nor
strengthened by other
layers as part of a laminate. Therefore, the fibres in non-solidified regions
are displaceable
relative to one another and it is not believable to the person skilled in the
art that such a
common nonwoven material is supposed to be down-proof. Contrarily, it must be
assumed
that this is alleged in DE 203 10 279 U 1 simply for the reason that a good
tightness against
allergen and mites was found and because down feathers are of a similar size.
However, one
cannot draw conclusions on the tightness against down on a basis of the
tightness against
allergens and mites. While allergens and mites are simply particles, down has
a unique hard
and pointed structure, with barbs and is easily able to bore through nonwoven
materials.
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The applicant of the present application has therefore tested whether the
allegation
of DE 203 10 279 U 1 that such fine microfibre nonwoven materials are down-
proof is true.
DE 203 10 279 U 1 includes an exemplary embodiment, but no details on the
origin or
manufacture of the exemplary nonwoven material are provided. The general
details on the
constitution of the microfibre nonwoven material are also relatively
superficial. The
microfibre nonwoven material described corresponds however essentially to a
commercially
available product of the trademark Evolon 100' of the company Freudenberg,
which was
commercially available in 2003. The product with the trademark Evolon is
manufactured out
of multi-component fibres including 16 microfibres per filament in a pie
shaped arrangement
(PIE16). Since the individual fibres are formed by pie shaped segments, they
exhibit an
angular cross-sectional profile which is pretty similar to a triangle. The
nonwoven material is
solidified by waterjet treatment, whereby the multicomponent fibres are split
into individual
filaments of polyethylene terephthalate (PET) and polyamide (PA). The fibre
thickness of the
multi-component fibre is about 2.4 dtex and that of the individual fibres
after the splitting is
about 0.2 dtex and 0.1 dtex. The nonwoven material Evolon 100 would thereby
with respect
to the polyamide fibre component be even finer than the one described in DE
203 10 279 U 1 .
It can however be assumed that the microfibre nonwoven material was described
and tested in
the exemplary environment of DE 203 10 279 U 1 was Evolon 100 of the
company
Freudenberg. This is supported in that the specifications in the utility model
application
essentially correspond with that of the Evolon 100 nonwoven material, that the
product
Evolon 100 was commercially available in 2003, and that no comparable products
of any
other manufacturers were commercially available in 2003. One also finds no
indication in the
utility model application that the applicant of the utility model manufactured
the product
itself.
In order to test the allegation of down-tightness made in DE 203 10 279 Ul,
the applicant of
the present application has tested whether a microfibre nonwoven material of
the trademark
Evolon, which is comparable with the nonwoven material of the exemplary
embodiment
of DE 203 10 279 U 1 , is in fact down-proof. It was thereby found, as
expected, that such a
microfibre nonwoven material does not have sufficient down-tightness. The
microfibre
nonwoven material does not fulfil the standardized pillow simulation test for
down-tightness
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according to DIN 12132-1 (see exemplary embodiment of the present application:
test with
Evolon 120, coated with 15g/m2 polyurethane or cross-linked polyacrylic binder
on the inside
of the down envelope; with pure down and goose feathers of class I of 90% down
and
10% feathers according to EN12934). The test protocol is originally for the
examination of
woven fabrics, but can be analogously used for nonwoven materials without
change in form
and content. A corresponding standard for nonwoven materials is not available,
only because
there was no need therefor in the art, since nonwoven materials in principle
are not down-
proof. Therefore, the general knowledge was confirmed that such nonwoven
materials are
allergen, mosquito bite, or mite proof, but not down proof.
The applicant further microscopically investigated the effect of down rachis
on such a
microfibre nonwoven material. The result is illustrated in figures 1 to 4.
Figures 1 and 2 show
a typical down rachis after penetration of the microfibre nonwoven material,
at different
magnifications. It is apparent from both illustrations that the down rachis
has a point with
which it can penetrate into the much finer nonwoven material. The rachis has
fine barbs
which support a directional penetration. Figure 3 shows a down rachis in the
process of
penetrating the nonwoven material. Figure shows a typical perforation which a
down has
drilled through the nonwoven material. Overall it is clear that the down
rachis can easily
penetrate a nonwoven material according to DE 10 2014 002232 Ul and that it
simply pushes
the fine individual fibres aside, whereby the directed penetration is further
supported by the
barbs. Such a fine microfibre nonwoven material cannot provide sufficient
resistance to such
pointy down rachis.
The absent down-tightness of the microfibre nonwoven material according to DE
203 10 279
Ul is in accordance with the common general knowledge according to which non-
thermally
solidified nonwoven materials, even though they consist of very fine fibres,
are not down
proof DE 20310279E01 does not include any teaching on how to overcome known
disadvantages of nonwoven materials with respect to their missing down-
tightness.
Nonwoven materials found in the prior art are therefore used for the storage
of down only
when sufficiently thermally solidified or lined with other layers in
laminates.
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WO 01/48293A1 relates to sleep clothing made of a microfilament nonwoven
material with a
surface weight of 60 to 200 g/m2 and the particle retention capacity of >90%
for particles of
<0.5 micrometer. During the manufacture of the nonwoven material,
multicomponent
continuous filaments are split and solidified to at least 80% to continuous
microfilaments of a
titer of 0.1 to 0.8 dtex.WO 01/478293 Al does not relate to the problem of
preventing the
penetration of such pointy down through nonwoven materials. The "particles"
are really fine
nanoparticles and in particular house dust mites and their excretions. In
contrast, down is
pointy and has length in the centimeter range. A good retention capacity for
nanoparticles
requires a highly fine fibre network but not any special mechanical stability.
It was therefore
to be assumed that a highly fine fibre structure made of mutually displaceable
fibres is in
particular not suited to prevent the penetration of thin, pointy and
comparatively large objects
such as pins, down rachis or mosquito stingers. It was therefore generally
assumed in the art
that only especially stable fibre products such as textile woven fabrics, can
prevent the
penetration of relatively large pointy objects.
It was also experimentally confirmed within the framework of the present
invention that even
nonwoven materials made of multicomponent fibres, which after splitting have a
significant
proportion of individual filaments with a titer of about 0.1 dtex, are not
generally down-proof
(see above discussion in relation to DE 203 10 279 Ul and its exemplary
embodiment).
Overall, the persons skilled in the art not have assumed that nonwoven
materials described in
WO 01/48293 Al could be down proof.
The object of the invention
It is an object of invention to provide materials for the storage of down for
textile applications
and textile products with good mechanical properties for the storage of down.
The textile
products preferably have good softness, elasticity, porosity, or air and
moisture permeability
but are to be down proof at the same time. The materials are preferably
relatively easily
available and the manufacturing process preferably excludes involved
processing steps, such
as lamination or special after-treatments.
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Disclosure of the invention
A nonwoven material made of continuous filaments is preferably used for
preventing the
leakage of down from a down-filled textile product. The nonwoven material is
preferably
available from a spinning process in which multicomponent fibres are deposited
into a
nonwoven web, whereafter the multicomponent fibres are split into continuous
filaments of a
titer of less than 0.15 dtex and the nonwoven web is solidified to a nonwoven
fabric by way of
a mechanical solidification including a fluid jet solidification, whereby the
nonwoven fabric is
not thermally or chemically solidified over a large area.
The material is preferably used for a down-filled textile product. The textile
product has an
envelope which encloses a cavity wherein the down are contained, separate from
ambient.
The nonwoven material forms the envelope of the textile product or at least a
part thereof.
According to the definition under DIN 61 210 (part 2, 1988), textile sheets
made of loosely
deposited fibres that are connected with one another by friction, cohesion or
adhesion are
nonwoven fabrics. The nonwoven fabric used as envelope and barrier keeps the
down from
leaking from the textile product.
The nonwoven fabric consists of continuous filaments. The term "filaments"
defines fibres
which in contrary to staple fibres are produced in a continuous process and
thereby directly
deposited into a nonwoven.
The term "down" as used throughout the present application covers down
feathers (under
feathers) of birds which are suited for textile fills. A definition of down is
found in DIN
12934. Down are in particular feathers with a very short rachis and long,
radially positioned
barbules. Down also generally have fewer barbs than other feathers. Because of
their high
elasticity and shape retention in connection with thermally insulating
properties down are
used for a multitude of textile applications.
The nonwoven material of the invention is preferably used for the prevention
of leakage of
down from a down-filled textile product. In such textile products, the down
fill is contained in
an envelope that separates the fill from ambient. The term "leakage" specifies
any movement
of the down by which the envelope is penetrated. The down can thereby
penetrate the
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envelope only partially or completely. The term "leakage" thereby includes the
situation that
rachis have penetrated into the envelope with only part of their tip and are
stuck or the down
may have completely passed through the envelope and exited the textile
product.
Down tightness is preferably determined by way of the simulated pillow stress
test according
to DIN EN 12132-1, Part 1, whereby the nonwoven fabric is used in place of a
woven fabric.
The nonwoven fabric preferably passes the test according to DIN EN 12132-2,
which means
that in each tested direction (longitudinally and transverse) not more than 20
particles
penetrate, which means have gotten stuck in the textile material or have
passed through it.
Preferably, an average of multiple individual measurements is analyzed,
especially of 5, 10 or
t) 20 individual measurements. Preferably, not more than 15 particles
penetrate during the test,
particularly preferably not more than 12 particles.
In a preferred embodiment, the nonwoven material is in direct contact with the
down fill. That
means that no further layer is present between the nonwoven material and the
down. The
down engage the nonwoven material and would penetrate it, if the down
tightness would be
insufficient. The nonwoven material is thereby preferably used as a textile
envelope in which
the down are contained. That means that the nonwoven material itself forms the
envelope. It is
therefore not a component of a laminate with further, different layers. Thus,
when the textile
product is for example bedding, the nonwoven material would directly enclose
the down. It
was surprisingly found in accordance with the invention that a nonwoven
material itself made
of fibres with a titer of less than 0.15 dtex can prevent the leakage of down
without the need
for a thermal solidification or lamination with other layers, especially woven
fabric layers or
stronger nonwoven fabric layers.
Multicomponent fibres are filaments made of at least two different parallel
continuous
filaments which have phase boundaries and are splitably connected with one
another. The
multicomponent fibres are split into continuous filaments of a titer of less
than 0.15 dtex. The
continuous filaments therefore have a titer of less than 0.15 dtex. That means
that the
nonwoven fabric has essentially or exclusively filaments of a corresponding
titer as filament
components. Such nonwoven fabrics can include local regions in which
multicomponent
fibres are not or only incompletely split. However, with sufficient mechanical
splitting,
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especially by way of a water jet, nonwoven fabric can be obtained which
consists almost
exclusively of individual filaments. Preferably at least 80% especially
preferably at least 90%,
at least 95%, at least 98% or about 100% individual filaments are present,
relative to the total
volume of the fibres. The proportion can be microscopically determined by the
testing of
randomly selected portions of a nonwoven fabric.
In a preferred embodiment, the splitting generates continuous filaments with a
titer of
less 0.14 dtex, less than 0.12 dtex or less than 0.11 dtex. The titer is
preferably larger than
0.01 dtex or larger than 0.025 dtex. The titer of all continuous filaments is
preferably between
0.01 dtex and 0.15 dtex, preferably between 0.02 dtex and 0.12 dtex or between
0.03 dtex and
0.11 dtex. The average titer of the continuous filaments is preferably between
0.01 dtex and
0.15 dtex, preferably between 0.025 dtex and 0.125 dtex, or between 0.03 dtex
and 0.11 dtex.
In a preferred embodiment, the nonwoven fabric includes as the continuous
filament
component a filament mixture, especially of two or three different filament
types. For
example, it is preferred that two or more continuous filament types with
different titers are
included. Multicomponent fibres are preferably used which include different
fine continuous
filaments made of different polymers. In a preferred embodiment, the nonwoven
fabric
includes at least two components and thereby continuous filaments with a titer
of less than
0.075 dtex, preferably less 0.065 dtex. The titer of a first fibre component
is preferably
between 0.80 dtex and 0.15 dtex, preferably between 0.80 dtex and 0.125 dtex
and a titer of a
second fibre component between 0.01 dtex and 0.075 dtex, preferably between
0.02 dtex and
0.065 dtex. The difference between the titer of the two components is
preferably at least 0.02
dtex. Especially by way of a commingling of a second, especially fine fibre
component, an
advantageous combination of down-tightness and stability can be achieved. The
proportion of
fibres with the lower titer is preferably at least 5 volume % or at least 10
volume %, especially
preferably 20 volume %. The amount of the fibre strands of the first and
second fibre
component is preferably equal. When the titer of the first fibres is twice as
high as that of the
second fibres, volume conditions of about 2 to 1 are obtained, which means
about 70 to 30.
It was surprisingly found that even relatively thin and light nonwoven fabrics
with relatively
low surface weight stand up to down. It was unexpected, since down rachis are
relatively hard
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and pointed and during conventional uses exert large forces on a nonwoven
fabric, especially
when they are pressed into a pillow envelope. Without being tied to a theory,
it is assumed
that the down when in a tightly intertwined nonwoven fabric of a fibre
fineness past a certain
threshold value are no longer able to displace the individual filaments with
respect to one
another and penetrate the nonwoven fabric. When this threshold value is
reached even a
thinner nonwoven fabric is sufficient in order to achieve the down tightness.
In contrast,
above the threshold value even a relatively thick nonwoven fabric is unsuited
for preventing
the leakage of down. Without being bound to a theory, it is assumed that the
down tightness is
achieved not only by way of the fine fibres, but also by way of the special
manufacturing
process with mechanical splitting of multicomponent fibres, by which an
especially dense and
homogenous mixing and intertwining of the filaments is achieved.
In a preferred environment, the nonwoven fabric has a surface weight of 70
g/m2 to 200 g/m2.
In a preferred embodiment, the nonwoven fabric has a surface weight of 90 g/m2
to 100 g/m2,
especially 100 g/m2 to 160 g/m2or of 110 g/m2 to 150 g/m2. The surface weight
is preferably at
least 70 g/m2or at least 90 g/m2, especially preferably at least 110 g/m2 in
order to guarantee a
high mechanical stability and down tightness. The surface weight is preferably
not higher than
200 g/m2, not higher than 160 g/m2 or especially not higher than 160 g/m2 in
order to achieve
sufficient porosity, with air and moisture permeability.
Nonwoven fabric with two fibre components is preferred, preferably made of
split
bicomponent fibres, whereby the titer of the first fibre component is
preferably between 0.08
dtex and 0.15 dtex and the titer of a second fibre component is preferably
between 0.01 dtex
and 0.075 dtex, whereby the proportion of the fibres with the lower titer is
preferably at least
10 volume % in connection with a surface weight of 70 g/m2 to 200 g/m2,
preferably 90
g/m2to 160 g/m2.
The nonwoven fabric is obtainable with a spinning process in which
multicomponent fibres
are deposited into a nonwoven mat, whereafter the multicomponent fibres are
split into
continuous filaments and the nonwoven mat mechanically solidified into a
nonwoven fabric.
The special internal structure of the nonwoven product is achieved with such a
manufacturing
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process, since the continuous filaments are especially tightly intertwined
with one another
therein.
The multicomponent fibres are preferably produced by melt spinning. During
melt spinning,
thermoplastic polymers are melted and spun into fibres. This process generally
allows for an
especially simple and reliable manufacture of nonwoven fabrics made of
multicomponent
fibres.
The multicomponent fibres preferably include two, three or more different
continuous
filaments. Preferably, the multicomponent fibres are bicomponent fibres.
Eventually, individual filaments are obtained by splitting off multicomponent
fibres which
have cross sections with corners or edges. This is advantageous, since the
individual filaments
are harder to move relative to one another. It is assumed that this improves
the
down-tightness.
In a preferred embodiment, the multicomponent fibres, for example, bicomponent
fibres, have
a pie-shaped (orange, "PIE-", pie) structure. The structure preferably
includes 24, 32, 48 or
64 segments. During splitting, the multicomponent fibre disintegrates into a
corresponding
number of individual continuous filaments (individual filaments). The segments
thereby
preferably include alternating polymers. Also suitable are hollow pie
structures that can also
have an asymmetrically axially extending cavity. Pie structures, especially
hollow pie
structures, are advantageous, since they can be especially easily split.
Furthermore, the
individual filaments preferably have an irregular cross section, which
increases the internal
solidity of the nonwoven fabric. The term "pie" or "pie shape" describes for
such highly fine,
split fibres actually the design of the spinning nozzle, and only
approximately the actual cross
section of the filaments. Preferred are multicomponent fibres in pie shape of
at least 32
segments, especially preferably exactly 32 segments, whereby no other fibre
component is
added. Such structures are conventionally available and evenly and easily
worked. The
surface weight is thereby probably at least 110 g/m2.
The fibre forming polymers of the multicomponent fibres are preferably
thermoplastic
polymers. The multicomponent fibres preferably include components which are
selected from
CA 02947826 2016-11-08
polyesters, polyamides, polyolefins and/or polyurethanes. Especially preferred
are
bicomponent fibres with a polyester component and a polyamide component.
In order to achieve an easier splitting, it is preferred to use multicomponent
fibres including
continuous filaments of at least two thermoplastic polymers (in different
components).
Preferably, the multicomponent fibres include thereby at least two
incompatible polymers.
Incompatible polymers are understood to be polymers which when combined result
in
pairings that do not adhere or adhere only conditionally and preferably with
difficulty. Such a
multicomponent fibre has a good splitability into elementary filaments and
enables an
advantageous ratio of solidity to surface weight. Polyolefins, polyesters,
polyamides and/or
polyurethanes are preferably used as incompatible polymer pairs in such
combination that
only pairings result which adhere only conditionally or only with difficulty.
Polymer pairs with at least one polyamide or with at least one polyester,
especially
polyethylene terephthalate are preferred because of their limited adhesion.
Polymer pairs with
at least one polyolefin are preferably used because of their difficulty to
adhere.
Combinations of polyesters, preferably polyethylene terephthalate, polylactic
acid and/or
poly-butylene terephthalate with polyamides, preferably polyamide 66,
polyamide 46, have
been found preferable, possibly in combination with one or more components in
addition to
the above mentioned, preferably selected from polyolefins. These combinations
have an
excellent splitability. Especially preferred are combinations of polyethylene
terephthalate and
polyamide 6 or of polyethylene terephthalate and polyamide 66.
Polymer pairs are also preferred which include at least one polyolefin,
especially in
combination with at least one polyester or polyamide. Preferred are thereby
for example
polyamide 6/polyethylene, polyethylene, terephthalate/polyethylene,
polypropylene/
polyethylene, polyamide 6/polypropylene, or polyethylene
terephthalate/polypropylene.
In a preferred embodiment, the volume ratio of the first to the second
continuous filament is
between 90:10 and 10:90, preferably between 80:20 and 20:80.
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The average cross-sectional area of the filaments should be less than 15 Mm2
or less than
Mm2. The cross-sectional area of cut filaments can be microscopically
determined. The
diameter of the endless filaments can also be theoretically determined from
the titers, taking
into consideration the densities, whereby the indication of the fibre diameter
is of little value
5 with angular filaments.
Suitable multicomponent fibres for the manufacture of continuous filaments by
way of
splitting are known in the art. The manufacture of such multicomponent fibres
is described
for example in FR 2 749 860 A or DE 10 2014 002 232 Al. A spun bonded fabric
line of the
brand Reicofil 4 of the company Reifenhauser, DE, can be used for example, for
the
10 manufacture of such spun fabrics.
The polymers form the fibre forming component of the fibres. The fibres can
additionally
include common additives. Additives are typically added to such fibre polymers
in order to
modify the workability during manufacture, or the properties of the fibres.
The use of
additives also allows adaptation to client-specific requirements. Suitable
additives can be
selected, for example, from the group consisting of pigments, antistatics,
antimicrobial agents,
such as copper, silver or gold, hydrophilizing agents or hydrophobizing
agents. They can be
added in amounts of up to 10 weight percent, up to 5 weight percent or up to 2
weight percent,
especially between 150 ppm to 10 weight percent (%/wt).
The nonwoven fabric was mechanically solidified. Mechanical solidification
includes a fluid
jet solidification. With mechanical solidification processes, such as the
fluid jet solidification,
the connection between the fibres is created by friction fit or by a
combination of friction and
form fit. The solidification is preferably achieved by a close into mixing of
the filaments. A
nonwoven fabric can thereby be achieved which has advantageous softness and
elasticity in
combination with good porosity. Sufficient down tightness is surprisingly
achieved, although
the individual fibres are actually displaceable relative to one another.
Preferably,
multicomponent filaments are also split into continuous filaments during the
mechanical
solidification.
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The fluid jet solidification occurs under the influence of pressure and
fluids. Solidification
thereby occurs by working with fluids under pressure, especially liquids or
gases. The
mechanical solidification further includes other complementary processes such
a pressing,
especially through calendering. Splitting of the multicomponent fibres
preferably occurs at
the same time as the fluid jet solidification. The solidification is therefore
carried out long
enough and with sufficient strength. The multicomponent filaments are
preferably split into
continuous filaments during the fluid jet solidification. A combination of
further mechanical
solidification processes can also be carried out in order to split the
multicomponent fibres
completely or at least as much as possible. At the same time, a close mixing
and
intermingling of the individual filaments is achieved.
Solidification includes a fluid jet solidification. Preferably, the fluid is a
liquid, especially
water. Therefore, the water jet solidification is especially preferred. Water
is preferred in
comparison to other fluids, since it does not leave any residue, is easily
available and the
nonwoven fabric can be easily dried. A deposited nonwoven web is thereby
subjected under
high pressure to a water jet whereby the nonwoven web on the one hand is
densified into a
nonwoven fabric and on the other hand multicomponent fibres in the web are
split into
individual filaments. It has been found that a water jet solidification is
especially suited to
achieve a close intertwining of the continuous filaments, which results in
good mechanical
properties and improves down tightness. The mechanical solidification,
especially the water
jet solidification is thereby carried out in such a way that the
microfilaments are not
compromised or not too much. Upon an excessively strong water jet
solidification of such
fine filaments, the mechanical stability and thereby especially the tear
propagation strength
(tear strength) is decreased. The nonwoven fabric preferably has a tear
propagation strength
according to DIN EN 13937-2 of 4 to 12 N, especially of 5 to 12 N or of 6 to
10 N.
Further mechanical solidification steps can be carried out to complement the
fluid jet
solidification and especially the water jet solidification. A solidification
can be carried out,
for example, by needling and/or calendering. In a preferred embodiment, a
presolidification
is carried out by way of needling and/or calendering, followed by a water jet
solidification.
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The calendering is carried out at a sufficiently low temperature so that no
thermal
solidification by adhesion of the fibres is carried out.
The nonwoven fabric was not thermally solidified over a large area. This means
that it was
not subjected continuously, which means over the whole nonwoven fabric
surface, to a
temperature treatment at which the fibres, or a melt adhesive, are softened to
such a degree
that fibres adhere to one another. The thermal solidification of the fibres is
achieved by
material adhesion, whereby the fibres are connected by adhesion or cohesion. A
nonwoven
fabric without thermal solidification is advantageous, since its softness and
elasticity is
maintained. In contrast, the mechanical properties are significantly changed
upon normal
thermal solidification and in a manner which is disadvantageous for textile
applications. In
particular, the nonwoven fabric is stiffer, which means less elastic and soft
and less porous so
that the air and moisture permeability is decreased.
The nonwoven fabric was not chemically two dimensionally solidified. This
means that the
fibres are not connected with one another by way of a chemical reaction and
especially not
cross linked by way of a binder. No covalent bonds were created between the
fibres.
In one embodiment, the nonwoven fabric can be thermally and/or chemically
solidified, but
only locally. Local solidification in partial regions which are evenly
distributed over the
nonwoven fabric surface can increase stability. The local solidification can
especially occur
in the form of a dot pattern. However, in order to maintain the typical
advantageous
properties of nonwoven fabrics, only a small portion of the nonwoven fabric
should be
solidified, preferably less than 30%, less than 10% or less than 5% of the
total surface. The
down tightness is thereby also provided in the non-solidified areas. The
localized thermal
solidification does not provide for, and is not needed for, the down-
tightness. Hovever, the
nonwoven fabric of the invention is preferably not thermally or chemically
solidified at all.
This means that no thermal or chemical solidification was carried out in order
to improve the
stability of the nonwoven fabric material over a large area. The advantageous
nonwoven
fabric property is thereby completely maintained. This does of course not
conflict with
inclusion in the nonwoven fabric of sealing seams, adhesive seams or other
regions which are
needed for the conversion into a textile product.
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Nonwoven fabric can be cured after the solidification by known processes, for
example by
drying and/or shrinking. The nonwoven fabric is then formed into an envelope
into which the
down is inserted and enclosed.
In a preferred embodiment, the multicomponent fibres have a pie shaped
(orange) structure
and are split into continuous filaments with a titer of less than 0.12 dtex
whereby the
mechanical solidification includes a water jet solidification and whereby the
nonwoven fabric
has a surface weight of 70g/m2 to 200g/m2. Preferably used are bicomponent
fibres,
preferably made of a polyester component and a polyamide component.
In a preferred embodiment, the nonwoven fabric has an average pore size of
511m to 20t.tm
and/or a maximum pore size of 10[im to 501.tm, measured by way of a pore size
measurement
apparatus PSM165 of the company Topas, DE according to the specification of
the
manufacturer and on the basis of ASTM E 1294-89 and ASTM F 316-03.
The thickness of the nonwoven fabric is preferably between 0.2mm and 0.6mm,
especially
between 0.25mm and 0.5mm, measured according to DIN EN 964-1.
The maximum tensile strength (breaking force) in all directions is preferably
at least
150 N/5cm, measured according to EN 13934-1. The breaking extension in all
directions is
preferably at least 20%, preferably at least 30%, measured according to DIN EN
13934-1.
The nonwoven fabric is preferably distinguished by very good water absorption.
The latter is
preferably between 250 ml/m2, especially more than 350 ml/m2 measured
according to
DIN 53923 in analogy for nonwoven fabrics.
The down tightness is preferably maintained even over long periods of use and
under normal
mechanical loads. It was found that the down tightness remains intact when the
nonwoven
fabric is repeatedly washed. Preferably, the nonwoven fabric is down tight
within the
meaning of DIN EN 12132-1 even after 5, 10 or 20 household washes according to
DIN EN
ISO 6330.
CA 02947826 2016-11-08
The air permeability according to EN ISO 9237:1995-12A is preferably at least
20 mm/s,
preferably at least 30 mm/s, measured with a test surface of 20 cm2 and a
differential pressure
of 200 Pa, preferably as a mean of 10 or 50 individual measurements.
The nonwoven fabric especially preferably has a surface weight of 90 g/m2 to
150 g/m2, an air
permeability according to EN ISO 9237:1995-12A of at least 20 mm/s and a tear
propagation
strength according to DIN EN 13937-2 of 4 to 12 N. It is advantageous in
accordance with
the invention that the down tightness can be achieved with very fine fibres
and relatively low
surface weights so that a sufficient air permeability for textile applications
is achieved.
The nonwoven fabric includes at least 12,000 km/m2 individual filaments per
surface unit,
especially preferably at least 13,500 km/m2 or at least 15,000 km/m2. The
number of the
individual filaments per surface unit can be calculated from the determined
surface weight
and the fineness of the individual filaments (in dtex), whereby it has to be
assumed that the
multi-component fibres were completely split. It was found that a high down
tightness can be
achieved by the adjustment of such a relatively high filament number per
surface unit with
highly fine fibres.
Overall, it is preferred to rely on the following properties of the nonwoven
fabric:
- a surface weight of 90 g/m2 to 160 g/m2, preferably of 110 g/m2 to
160 g/m2,
- a high air permeability according to EN ISO 9237:1995-12A of at least
20 mm/s,
preferably of at least 30 mm/s and
- at least 12,000 km/m2, preferably at least 13,500 km/m2 of individual
filaments per
surface unit.
The nonwoven fabric preferably includes or consists of continuous filaments
which have a
titer of less than 0.075 dtex. Especially preferably, the nonwoven fabric
consists of 32 PIE-
multi-component fibres or includes such fibres.
As discussed above, the nonwoven fabric is in and of itself suited for the use
in accordance
with the invention. Nevertheless, it is conceivable to strengthen the nonwoven
material with
further textile layers. The use in accordance with the invention can, for
example, consist of a
16
CA 02947826 2016-11-08
laminate of the nonwoven fabric with at least one further layer, for example
one or two further
layers. It is thereby preferred that the nonwoven fabric is immediately
adjacent the down and
thereby forms a barrier. On the outside directed away from the down, the
nonwoven fabric
could be provided with at least one further layer to provide the laminate with
a desired further
property, such as moisture protection or increased mechanical strength.
However, even in
such a laminate, the purpose, which means the object of achieving down
tightness, is achieved
by the nonwoven fabric itself, which forms a physical barrier for the down.
Additional layers,
especially on the outside are preferably applied for another purpose, which
means they do not
or only immaterially improve the down tightness.
A down filled textile product is also provided the invention, especially
selected from bedding,
jackets, upholstery, mattresses or sleeping bags, including a textile envelope
and down
contained therein. The envelope includes a nonwoven fabric of continuous
filaments for
preventing the leakage of the down, whereby the nonwoven fabric is obtainable
with a spin
bonding process in which multi-component fibres are deposited into a nonwoven
mat,
whereafter the multi-component fibres are split into continuous filaments with
a titer of less
than 0.15 dtex and the nonwoven mat is solidified into a nonwoven fabric by
way of
mechanical solidification, including a fluid jet solidification, without
chemical or thermal
solidification of the nonwoven fabric.
The end result is a textile layer has a suitable form to store down therein.
The textile envelope
can consist essentially of the nonwoven fabric. This means that the nonwoven
fabric forms at
least part of the textile envelope by which the storage of the down and their
separation from
ambient is achieved. The textile envelope can be further modified for other
purposes, for
example with decorative elements or closing elements such as buttons or
zippers.
The textile product is preferably a bedding product, a jacket, a cushion, a
mattress or a
sleeping bag. The textile product is especially preferably a bedding product.
Because of the
down tightness in combination with the good mechanical properties and
especially the high
softness and elasticity, the nonwoven fabrics of the invention are especially
well suited as
body covers or underlays, such as duvets, pillows or mattress covers.
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In a preferred embodiment, the down is goose down. Those penetrate textile
envelopes
especially easily because of their hardness and shape. It was found that the
use in accordance
with the invention with the special nonwoven fabrics enables one to down tight
store even
goose down.
Apart from down, the filler can also include also other conventional filler
materials, such as
feathers or synthetic fillers. Down are often used for textile applications in
mixtures with
feathers. Preferably the proportion of the down in the fill is at least 30
weight % or at least
50 weight % , especially at least 70 weight %.
It is also an object of the invention to provide a process for the manufacture
of the down filled
1() textile product, including the steps of:
(a) provision of the textile envelope which includes the nonwoven fabric of
continuous filaments,
(b) filling of the textile envelope with down, and
(c) sealing of the textile envelope down tight.
The down tight sealing can be achieved, for example, by thermal sealing,
stitching, gluing or
other conventional processes. Since, in particular, spinnable and therefore
thermoplastically
processable polymers are used, sealing by thermal connecting processes such as
ultrasound
stitching or welding is especially preferred.
The nonwoven fabrics in accordance with the invention are advantageous to a
high degree,
since they are not only down tight but frequently also provide protection
against allergens
such as pollen or house dust or mosquito bites. The latter is especially
advantageous, since
woven fabrics in general do not provide any protection against mosquito bites.
The
nonwoven fabrics useable in accordance with the invention therefore offer
overall and
inordinately high protection against disturbing environmental influences.
The nonwoven fabric is overall distinguished by an advantageous combination of
properties.
The mechanical properties, for example with respect to maximum tear strength,
maximum
extension strength, isotropy, expansion module or tear propagation strength
are excellent and
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readily allow for applications in the textile field. Moreover, the nonwoven
fabric has
advantageous properties especially for typical textile applications such as
absorption,
shrinking by washing or pore size. Overall, it was surprising that a
combination of preferred
properties could be achieved in connection with high down tightness without
the need for
thermal or chemical solidification, even at low surface weights. In
addition, it is
advantageous that the nonwoven fabric can be manufacture easily without the
requirement for
special process steps such as lamination or chemical curing.
The materials for its
manufacture, especially multi-component fibres and corresponding continuous
filaments, are
also easily obtained and processed.
The nonwoven fabric in accordance with the invention has a very good down
tightness, while
comparable nonwoven fabrics with somewhat thicker fibres have no down
tightness at all. It
was thereby surprising that the down tightness did not increase proportionally
to the fineness
of the fibres, but that nonwoven fabrics with fibres up to a certain fibre
thickness are wholly
unsuited for the storage of down, while fibres with higher fineness all of a
sudden have a high
down tightness. It could not have been expected that the down tightness would
be achieved
especially with very fine fibres and certainly not all of a sudden. One would
have rather
expected that very fine fibres could no longer be able to counteract the hard
and pointy down
rachis with sufficient mechanical strength. It is therefore made possible by
the invention to
use only mechanically solidified nonwoven fabrics for the storage of down.
Figures
Figures 1 to 4 show microscopic photographs of a state of the art nonwoven
fabric which was
penetrated by a down rachis.
Figure 1 shows at 100x magnification a typically hard and pointy down rachis
with barbs
which penetrates a conventional nonwoven fabric.
Figure 2 shows a typical down rachis with barbs in 2000x magnification. The
radius of the
tip is about 3.6 p.m and the diameter below the tip is about 19.1 p.m.
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CA 02947826 2016-11-08
Figure 3 shows in 100x magnification a conventional nonwoven fabric which is
penetrated by
a down rachis.
Figure 4 shows in 100x magnification a perforation in the conventional
nonwoven fabric
from Figure 3, which was bored by a down rachis.
Exemplary Embodiments
Examples 1 to 4: Manufacture of Nonwoven Fabrics
The manufacture of nonwoven fabrics of bicomponent fibres with pie-shaped
cross-section
and using a bicomponent spunbond nonwoven line is described by example in the
following.
Two nonwoven fabrics in accordance with the invention were produced with 32
individual
filaments (type "PIE 32") and surface weights of about 100 g/m2 and 130 g/m2
(examples 2
and 4). For comparison with the state of the art from DE 203 10 279 Ul , two
nonwoven
fabrics were made of bicomponent fibres with 16 individual filaments (type
"PIE 16) and
surface weights of about 100 g/m2 and 130 g/m2 (examples 1 and 3). The
components and
manufacturing conditions are summarized in the following.
Raw Materials Proportions
Polyester, INVISTA, DE 70
Polyamide 6, BASF, DE 30
Hydrophil, CLARIANT, CH 0,05 in PET
Ti02, CLARIANT, CH, Renol WeissTM 0,05 in PET
Antistatic, CLARIANT, CH, HostatstatT" 0,05 in PA6
Extruder
PET, Zones 1-7 270-295 C
PA6, Zones 1-7 260-275 C
CA 02947826 2016-11-08
Spinning Pumps
Volume, Rotation Speed, Throughput PET: 2x10cm3/U, 16,56 U/min, 0,923g/L per
min
Volume, Rotation Speed, Throughput PA6: 2x3cm3/U, 26,25 U/min, 0,377 g/L per
min
Total Throughput: 1,3 g/L per min (71/29)
Nozzles
Nozzle Type: PIE 16 or PIE 32, pneumatic stretching
Laying Down
Onto a carrying belt with pre-adjusted speed, which results in a nonwoven
surface weight of
100 or 130 g/m2.
Solidification
Pre-solidification by needling with 35 stitches/cm2 and subsequent calendering
with steel
rollers smooth/smooth at 160-170 C and 65-85 N line pressure.
Final solidification with splitting of the bicomponent filaments into
individual filaments
through water jet solidification with 4 to 6 alternating passes on the upper
side A and
underside B of the nonwoven fabrics in the sequence ABAB(AB) at 220-250 bar,
with a
nozzle strip hole diameter of 130 p.m on a carrying belt of 80 mesh.
Aftertreatment/Curing
The nonwoven fabric is subsequently dried with a cylindrical through-air dryer
at 190 C and
partially shrunken in order to enable as much as possible a shrinkage upon
wash of <3% in the
first hot wash.
The production speeds in the process steps subsequent to the exit from the
nozzles depend on
the desired surface weight.
Example 5: Properties of the Nonwoven Fabrics
Properties of the nonwoven fabrics produced in accordance with Examples 1 to 4
which are of
importance for typical textile applications were tested with appropriate
measurement
21
CA 02947826 2016-11-08
protocols. Unless otherwise indicated, the testing was carried out according
to the following
standards, in force at the filing date.
Property Unit Standard
Surface Weight g/m2 EN 965
Thickness mm EN 964-1
Tear Strength N/5cm EN 13934-1
Breaking Extension EN 13934-1
Module N EN 13934-1
Porosity tm ISO 2942 / DIN 58355-2
Tear Propagation Strength N EN 13937-2
Wear Martindale (9kPa) Tours EN 12947
Pilling Note adapted from DE. 53867
Water Absorption adapted from DIN 53923
Household Wash (shrink % at DIN EN ISO 6330
95 C)
Air Permeability (air stream mm/s DIN EN ISO 9237:1995-
measurement protocol) 12A
The results are summarized in the following Table 1.
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Table 1: Properties of Nonwoven Fabrics According to Example 5
Example 1 2 3 4
(Comparison) (Comparison)
- _
Type PIE16 PIE32 PIE16 PIE32
,
'
Surface Weight (g/m2) 99 97 130 127
Thickness (mm) 0,37 0,33 0,44 0,41
Titer Individual Filaments dtex 0,2 / 0,1 0,1 / 0,05 '
0,2 / 0,1 0,1 / 0,05
Physical Textile Testing Carried Out at 20 C, 400m m/min
Tear Strength longitudinally (N) 320 275 424
292
transverse (N) 290 237 388 192
Isotropy 1,1 ' 1,16 1,09
1,52
Breaking Tension longitudinally (%) 48 ' 40 42
35,5
transverse (%) 51 ' 51,5 46 39
Module / 3 % longitudinally (N) 73 ' 76 84
84
transverse (N) 36 31 43 26
Module! 5 A longitudinally (N) 89 93 110
104
,
transverse (N) 48 40 59 35
,
Module! 15% longitudinally (N) 150 154 209
175
,
transverse (N) 102 77 134 75
Module! 40 A) longitudinally (N) 285 276 417
-
,
transverse (N) 240 190 333 206
,
Tear Propagation Strength longitudinally (N) 8,5 7 8,6
5,5
,
Before Washing transverse (N) 9,8 10 11,4 10,2
Pilling underside/ 4,5 / 4,5 - 4,5 / 5
3,5 / 3,5 5+ / 5+
top
Absorption (1/m2) 350 400 490 467
Wear Martindale Hole 12000 20000 16000 35000
9 kPa Formation
After 95 C-Wash
Aspect 2,5 1,5 2 1,5
Shrink Upon Washing longitudinally' (%) 4,8 2,4 3
2,6
transverse (%) 3 3,1 2,4 1
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After 3 Washes
Aspect 2,5 1,5 2,5 1,5
Permeability
Average Pore Size 25 12 18 8
Maximum Pore Size 75 37 59 21
Air Permeability (mm/s) 71 37
The results show that all four nonwoven fabrics have good textile properties.
At the same
surface weight, the nonwoven fabrics for use in accordance with the invention
of the type PIE
32 (examples 2 and 4) have a better washing resistance, allergens tightness
and mosquito bite
tightness compared to the comparison nonwoven fabrics of the type PIE 16
(examples 1 and
3).
Example 6: Down Tightness:
The testing of the down tightness was carried out with the simulated pillow
stress test
according to DIN EN 12132-1. This standard is used for the testing of the down
tightness of
woven fabrics and is analogously useable for nonwoven fabrics. According to
Part 1, a
simulated pillow stressing was carried out. The testing was carried out on two
pillows of the
dimensions 120 mm x 170 mm. With pillow 1, the longer side extends in
direction 1. With
pillow, the longer side extends in direction 2. White, new, pure goose down
and feathers of
Class 1, 90% down/10% feathers was used as filler material. This testing
material
corresponds to EN 12934 ¨ Characterization of the composition of finished
feathers and
down. The result determined was the number of downs/feathers or particles
which penetrated
after 2,700 rotations. According to the definition, a sample is down tight
which has a result in
all directions of 20 or less.
For the nonwoven fabric according to Example 2 (PIE 32, 97 g/m2 surface
weight), a result of
16 was achieved in direction 1 (1 particle stuck in the textile material, 15
particles in the
plastic bag), and in direction 2 a result of 34 (2 particles stuck in the
textile material, 32
particles in the plastic bag). For the nonwoven fabric according to Example 4
(PIE 32,
127 g/m2) a result in direction 1 of 9 was achieved (2 particles stuck in the
textile material, 7
particles in the plastic bag) and in direction 2 a result of 3 (0 particles
stuck in the textile
24
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material, 3 particles in the plastic bag). These results show that the
nonwoven fabric in
accordance with the invention has an excellent down tightness. The down
tightness of a
nonwoven fabric in accordance with the invention having a surface weight of
100 g/m2 is
already high, while the down tightness at 130 g/m2 fully corresponds to the
requirements for
bedding.
For comparison, a nonwoven fabric made of a mixture of continuous filaments
with a titer of
0.1 dtex and 0.2 dtex was tested. The nonwoven fabric was manufactured
analogous to
Example 1, but had a surface weight of 120 g/m2 and was additionally provided
with a
stabilizing coating of polyurethane (15 g/m2). After a household wash, the
simulated pillow
to stress test according to DI NEN 12132-1 provided a result in direction 1
of 42 (5 particles
stuck in the textile material, 37 particles in the plastic bag) and in
direction 2 of 35 (3 particles
stuck in the textile material, 32 particles in the plastic bag). This nonwoven
fabric therefore
has no down tightness which would be sufficient for textile applications.
Upon microscopic investigation it was found that the rachis of the down easily
penetrate such
comparative nonwoven fabrics (Figures 1 to 4). The nonwoven fabrics made of
continuous
filaments with a titer of 0.2 and 0.1 dtex cannot offer sufficient strength
against the hard,
pointy rachis with barbs.
These results show that the comparative nonwoven fabrics are not down tight,
as expected. It
was, however, surprising that a somewhat finer nonwoven fabric is down tight.
Figure 2
shows a typical pointy rachis with a tip which is about 3.6 i,tm wide. The
circumference of the
tip is significantly smaller than the average pore size between 8 and 25 [tm
of all four
nonwoven fabrics of Examples 1 to 4. One would therefore have expected that
the rachis will
penetrate through all four nonwoven fabrics. In addition one would have
expected that the
finer fibres provide even less resistance against a hard and pointy object.
Without being
bound by theory, the special down tightness of the nonwoven fabrics for use in
accordance
with the invention could be caused by the internal structure made of the
closely interwoven
continuous filaments.
CA 02947826 2016-11-08
Example 7: Importance of Surface Weight and Fibre Number
Nonwoven fabrics made of 32 PIE bicomponent fibres or mixtures with 50% 16 PIE
and 32
PIE bicomponent fibres with different surface weights were manufactured. As
described in
Example 6, the down tightness of the nonwoven fabrics was determined with a
simulated
pillow stress test for woven fabrics analogous to DIN EN 12132-1. How many
individual
filaments per surface unit of the nonwoven fabric were present (1 dtex
corresponds to
g/km) was determined from the fibre fineness of the individual filaments.
The fibres and split filaments had the following properties:
10 Material: Polyethylene Terephthalate/Polyamide 6 (PET/PA6) in a
ratio of about 70/30
Fineness:
PIE 16: Fibres before splitting 2.4 dtex
Filaments after splitting: PET 8x 0.2 dtex / PA6 8x 0.1 dtex
Average diameter filaments: 0.15 dtex
PIE 32: Fibres before splitting 2.4 dtex
Filaments after splitting: PET 16x 0.1 dtex / PA6 16x 0.05 dtex
Average diameter filaments: 0.75 dtex
Length of the Filaments Per Weight
PIE 16: about 66.7 km/g
PIE 32: about 133.3 km/g
The properties of the nonwoven fabrics and their results are summarized in
Table 2 below.
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Table 2: Properties of Nonwoven Fabrics According to Example 7
Non- Type Theoretical Measured Filaments Penetrations
Penetrations Air
woven Surface Surface Per Surface by Down
by Down Permeability
No. Weight Weight Area @200Pa
PIE [g/m2] [g/m2] [km/M2] Number
Average [mm/s]
MD+CD Number
A 32/16 100 102 10.200 30 + 30 30
119
B 32/16 130 132 , 14.960 20 + 12
16 69
C 32 100 99 13.200 17 + 13 15 81
D 32 100 100 13.333 19 + 32
20,5 89
E 32 110 110 . 14.667 24 + 19
21,5 49
.
F 32 120 125 . 16.667 15 + 10 12,5 52
G 32 120 120 16.000 8 + 5
7,5 52
I H 32 130 130 17.333 9 + 4 6,5 48
(MD = machine direction CD = cross machine direction)
As already discussed above in relation to Example 6, it is assumed that a
sample is down tight
when a result of 20 or less penetrations is achieved in all directions.
According to DI NEN
12132-1, the nonwoven fabrics B, C, F, G, and H are therefore down tight. The
nonwoven
fabrics also have good air permeability and are therefore suitable for textile
applications, for
example as bedding. The results show that it is advantageous to coordinate the
filament
fineness and the surface weight in such a way that a sufficiently high number
of fibres is
present per surface unit. It can thereby be advantageous when relatively fine
filaments are
used to adjust the surface weight in such a way that a desired air
permeability is provided.
27
