Note: Descriptions are shown in the official language in which they were submitted.
~ he invention relates to a multifilament yarn con-
sisting of individual filaments of the multicomponent matrix-
segment type, which contains the individual filaments essentially
as a matrix and at least three segment-fibres split therefrom,
the segment-fibres being shrunk by at least 10% in relation
to the matrix. The invention also relates to a method for
producing the yarn according to the invention.
Yarns made of individual filaments of the multi-
component matrix-segment type are described in Canadian Patent
Application SN 322,710, Klaus Gerlach et al, filed March 2, 1979
and Canadian Patent Application S~ 320,168, Erich ~essler et al,
filed January 24, 1979. These yarns consist of at least two
different polymers with quite different shrinkage behavi.our
whereby complete or partial separation of the components is
obtained.
It has now been found that surprising effects may
be obtained, under certain conditions, when imparting to.yarns
of this type a false-twist texture, by appropriate selection
of the polymers processed together and of the texturising
conditions.
It is therefore the purpose of the invention to
prepare a yarn from individual filaments of the multicomponent- ~ -
matrix type which may easily be processed into sheets without
twisting, sizing, or any other treatment for the purpose of
closing the yarn, and in which the components constitut.ing the
yarn in the fin:ished sheet show a very fine individual titre.
According to the invention there is provided a
multifilament yarn consisting of individual filaments of the
multicomponent matrix-se~ment type, which contains the
individual filaments essentially as a matrix and at least
three segment fibres split therefrom, the segment fibres being
shrunk by at least l~/o with respect to the matrix, the individual
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components of the yarn having a false-twist crim~, the
indivldual components being united, at least in part, ln the
yarn assembly, at irregular intervals, by weld or adhesive
locations at leastpartially covering the cross-section
the yarn.
The individual components of the yarn may be united
wholly or partially at the irregular intervals, by adhesive
locations which completely or partially cover the cross-section
of the yarn.
The matrix-component may,be made of a polyamide and
the segment-component of polyalkylene-terephthalate. In one
particularly suitable combination, the matrix-component is a
caprolactam and the segment-compOnent is a polyethylene~
terephthalate.
Suitably the weight ratio of matrix-component to
seyment-component i9 about 5 : 95 ~o 45 : 55, preferably about ~'
10 ~ 90 to 25 : 75. ~,
A variety of multicomponent filaments are envisaged
in the yarn of the invention. It is especially preferred to ~ ,';
employ a multicomponent filament which comprises a matrix-
component and at least six segment-components. Suitably the
segment-components have individual titres in a range of about
0.08 to about 2.0, preferably, about 0.1 to about 1.4 dtex.
The yarn suitably has a false-twist crimp of an
intensity of about 1500 to 4500 twists/metre, with the number
of weld or adhesive locations uniting more than two individual
components averaging about 5 to 40 per metre.
In another aspect of the invention, khere is provided
a method for producing a yarn of the invention in which a
multifilament yarn made of individual filaments of the multi- -
component matrix-segment type is subjected to a false-twist
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treatment in which the setting temperature used is at least
that required for the component having the lowest metling temper-
ature, and wherein the twist-density is selected, dependent
upon the total titre of the multifilament yarn made of
individual filaments of the matrix-segment type, between about
1500 and 4500 twists/metre.
In this case, it is preferable of the setting tempera-
ture to be between about 180 and about 2~0C, more particularly
between about 190 and about 230C.
It has been found advantageous for the twist-density
in the fixing section to be such that it corresponds to the
normal twist-density ùsed in texturizing a normal multifilament
polyethylene-terephthalate yarn of approximately the same titre.
Within the meaning of the invention, the term yarns
includes, in addition to endless, multifilament linear material
made of endless or staple fibres, structures such as weaves,
knits, tricots and fleeces.
In another aspect of,the invention there is provided
a textile structure, for example a knitt~d, tricot or woven
textile structure composed of yarns of the invention, and a
method for its preparation~
It is advantageous for the multifilament ~arn con-
sisting of individual filaments of the multi-component matrix-
segment type of the invention to be subjected, at a setting
temperature of between about 190 and 240C, to a false-twist
treatment, which produces between about 10 and 40 adhesive
locations per metre, and thereafter to be processed into a
textile structure; this structure is then subjected, in an
organic solvent which reduces the zero shrinkage temperature
of the segment-component by at least 160C, to a simultaneous
shrinking and full,ng treatment. ~he fulling treatment is
highly intensive, in order to prevent a subsequent change in
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feel during use.
In the reduction oE the zero shrinkage temperature
suitably about 50 to 8~/o of the uniting locations are released.
The false twist process preferred is the stretch-
texturizing process, the stretch-ratio being selected, in known
fashion, having regard to the end-product desired~
Methylene chloride, 1,1,2,2-tetrachlorethane, 1,1,2-
trichlorethane and chloroform have been found particularly
effective as organic solvents.
Shrinkable, within the meaning of the invention, ~ :
signifies that the segment-component fibres may be shrunk, for ~ .
example, by treatment with the solvents used in accordance ;~ :
with the invention, :
It is significant that the seyment-components shows
substantial shrinkage in the solvents of the invention, it ~ :~
is desirable for this shrinkage to amount to at least 10%,
preferably at least 15%. Persons skilled in the art will ~e
familiar with ways of determining the shrinkage behaviour.
It is important for the matrix and segment-components
to display different shrinkage behaviour in the solvent; for
example, the segments-component may suitably shrink, whereas
the matrix-component does not. Or the amount of shrinkage
may be different. It is essential, however, for the induction-
time, that is the time until the shr:inkage becomes no-ticeable
in the treatment medium, to be different. Suitably the
shrinkage induction-time of the se~nent~components is as short
as possible, preferably of the order oE seconds. 'rhe difference
in shrinkage behaviour may also be manifested in that the shrink-
age velocity of the peripheral segments of the yarn is greater
than that o~ the matrix-~omponent. Information regarding the
determination of the induction-time may be gathered from two
publications by NoL~ LINDNER in the periodical "Colloid and ~:
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Polymer Sci.", 255, pages 213 et seq. and 433 et seq. (1977).
It is also the purpose of the invention to produce
knitted, tricot or woven material having special feel and wear
properties.
This is achieved by processing wholly or partly
false-twist texturized multifilament yarn of the invention
into a knitted, tricot or woven textile structure. The object
of the invention is therefore textile structure obtained in
this way.
In one embodiment of the invention a multifilament
yarn consisting of individual filaments of the multi-component
matrix-segment type were subjected, at a setting temperature `
of between about 190 to 240C, to a false-twist treatment
producing about 10 to 40 weld or adhesive locations per metre.
After being processed into a textile material, they were
subjected, in an organic solvent which reduced the zero-
.
shrinkage temperature of the segment-component by at least
.
100C, to a simultaneous shrinking and fulling treatment. The
fulling treatment was highly intensive, in order to prevent
any subsequent change in feel during use. The yarns in the
finished, after-treated material showed a reduction of between
about 50 and ~0% in weld locations.
It is particularly advantageous to stretch--texturize
the yarns used for ~he material of the inventionj the stretch-
ratio being selected, in a manner known per se, ln adaptatlon
to the desired end-product.
A suitable setting temperature thus makes it possible
to obtain a wide range of different degrees of feel in the
material. In this connection, the fulling treatment, carried
out simultaneously with the solvent treatment, is particularly
signlficant. This fulling treatment must be so thorough that
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it is impossibl~ for the feel of the material to change any
further during use, or during wear, as a result of the release
of further weld-locations or any separation between the matrix-
and segment-components.
The splitting-off of the texturized multicomponent
yarns, especially the release of weld locations, is best
carried out after the yarns have been processed, according to
the invention, into textile and technical or industrial
structures.
It is of particular advantage to produce structures
including knits, tricots and weaves, using a texturized yarn
o~ the invention which, upon being-texturized by heat treatment,
acquires at least about 10, but if possi~le not more than 40,
weld locations per metre of yarn length.
Yarns of the matrix-segment type, upon which the
in~ention is ~ased, are made from polymers which are not
miscible with each other, do not react chemically with each
other and, when mixed with each other in the melt or placed
side by side, and spun into a multicomponent yarn, display
a distinct phase boundary under given conditions. Preferred
e~amples of such incompatible polymers are polyamides and
polyesters, special preference being given, within the scope
of the invention, to polyesters based upon terephthalic acid.
These polymers also fail to show, in the melt, at least within
specific times, an~ rloticeable chemical reaction with each other.
Thus no, or scarcely any, mixed polymers are formed which would
cause the two phaes to adhere together more firmly. It is to
be understood that exchange reactions, which may o~cur between
polyesters and ~olyamides in the melt over longer periods of
time, as described for example in Doklady Akademii Nauk USSR
1962, Vol. 147, ~o. 6, pages 13, 165 to ~, are disregarded~
~126~ 5
Multicomponent yarns, having a matrix and a plurality
of components axranged in segments, are to be understood to
mean yarns in which the individual segments and the matrix
are arranged continuously along the axis of the yarn, so
that the cross section of the yarn is substantially the same
along its length. Examples of suitable yarn cross sections
for the invention are illustrated in Figures 1 to 7, of the
drawings the matrix being marked a and the segments b.
Organic solvents, within the meaning of the invention,
are chemical substances which,can physically dissolve other
substances. It is unnecessary and, as a rule, even undesirable '~
for the solvent to dissolve one or all of the polymers con-
stituting the multicomponent yarns. In exceptional cases,
however, it is appropriate to dissolve the matrix-component, ~'
' for example, wholly or partly out after processing into a~material. ,
The solvent should allow the segment-component fibres to shrink
sharply, bu~ the matrix only slightly or not at all.
The zero shrinkage temperature may be determlned by
a method described, for example, in Lenzinger Berîchte, May
1976, sequence 40, pages 22 to 29. This deals with dynamic
shrinkage curves for yarns in the solvent under consideration
for treating the multicomponent yarns. Extrapolation of the
linear portion of the dynamic shrinkage curve gives the æero
shrinkage temperature as the intersectlon with the abscissa.
It has been found, that the above-mentioned solvents,
in particular, methylene chloride, l,1,2,2-tetrachlorethane,
1,1,2-trichlorethane and chloroEorm, reduce the zero shrinkage
temperature of the segment-component adequately and produce
an unexpectedly satisfactory splitting~off of the multi~
component yarns.
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Multicomponent yarns, used as starting materials in ~ -
the method of the invention may be produced in various ways
by spinning suitable polymers by the melt-spin process using
appropriate nozzles or spinning means, and by stretching in
the normal manner. Such multicomponent yarns may be produced
particularly advantageously by the method and device described
in the afor mentioned Canadian Patent Application SN 322,710.
The choice of the proportions, by weight of the
matrix- and segment-components is a significant factor. Parti-
cularly in the case of yarns having a content by weight of
matrix-component of about 10 to 25% it has been found that
dissolving the weld locations is considerably facilitated, if
a setting temperature of about 225 to 230C, or 235C at the
most, is not exceeded.
Decisive factors in the structure of the finished
yarn of the invention are, in general, the distribution of the
matrix- and segment-components, the degree of twist applied,
and the setting temperature. It has been found, in particular
that if the effect of the invention is to be achieved at all,
the temperature used for thermosetting must correspond at
least to that re~uired for the yarn component having the lowest
melting point, that is the yarn component constituting the
matrix.
The more this temperature is exceeded, the larger
the number of weld locations, not only those present after
the texturi3ing process, but also those which can no longer
be released by, for example, dissolving.
Suitable selection of the setting temperature thus
makes it possible to achieve in the matsrial a wide range of
different deyrees of feel. In this connection, the fulling
treatment applied simultaneously with the solvent treatment
is of special signi~icance. The fulling treatment must be so
thorough that the feel of the material during wear or use
does not change as the result of the release of additional weld
or adhesive locations, or of further separation between the
matrix- and segment-components.
The choice of the matrixprofile depends upon the final
properties required. The finer the individual segment-titre
re~uired, the higher is the number of segment-components
required per matrix-component.
The splitting-off of the texturized multicomponent
yarns, especially the release of adhesive locations, may be
carried out not only in structures such as staple fibres or
endless yarns, but also in structures obtained by processing
texturised multicomponent yarns into textile and technical
structures.
Structures including knits, tricots and weaves may
be produced particularly advantageously by using a texturized
yarn which acquires, during texturising by heat-treatment, at
least about 10, but if possible not more than 40 adhesive
locations per metre o~ yarn.
There may also be cases in which a yarn, exhibiting
only very few locations with still recognizable individual
filaments, and strongly resembling a monofilament in its
processing behaviour, is of special interest because of its
sharply stnlctured surface. These are covered by the inven-
tion, but are only a marginal objective.
Especially if the matrix-proportion of the yarn is
in the lower range, that is about 15% by weight, the choice
of a suitable setting temperature during texturising may
have the result that only the segment-components can be made
; out in the finished yarn, whereas the matrix is torn and
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adheres to the seg~ent-component-fibres only in pieces of
diferent sizes, the dimensions of some of them being below
the resolving ability of a light-microscope. In such cases
it may be definitely advantageous to release the matrix por-
tion out of the structure, leaving only the very fine titre
segment poritons for example with individual titres of about
0.1 to 0.3 dtex.
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