Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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This invention rel~tes to a process for the ~uantit-
ative application of liquid systems in a thin la~er to natural
or synthetic filaments moving uniformly along a linear path by
the one-way technique using a forced dosage unit.
Coating filaments with liquid systems, for example with
spinning preparations, i5 aimed in particular at æacilitating
the friction-frea movement of the threads. In addltion, the
coating used is frequently an antistatic agent. Finally, the
filament has to be charged with water in dosed form. These
requirements mean that the coating agent has to be in the form
of an emulsion having an outer phase of water and an inner
phase of oil.
In conventional processes for the application of such
an emulsion, the filaments are run past a rotating porous roller
(godet) the filaments contactin~ the rollex at a tangent. The
roller dips into an emulsion and transfers the emulsion to the
filaments through its rotation and contact with the threads.
The amount of emulsion transferred is deter~ined inter alia by
the speed of rotation. The emulsion in the pan is continuously
replenished by a pumping system.
One disadvantage of coating processes of this kind is
that there are many fluctuations in the amount of emulsion
applied. These difficulties are predominantly attributable to
the fact that the supply of emulsion on the roller is relati~ely
large and the filaments take up as much emulsion as they can,
depending on how they are guided over the roller. There is no
means to make the fibres take up an accurately defined quantity.
Also, the properties of the roller surface change with time;
wear phenomena occur, and also the properties of the emulsion
change~ for example due to bacterial effects. Decay and ageing
effects of this kind result in troublesome changes in viscosity
and the consequent fluctuations in the amount of oil applied
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cause fluctuations in ~riction when the filaments are being
stretched. The resulting stretching errors lead -to differiny
filament strengths, filament breakages- occurring in extreme
cases. In addition, fluctua-tions in the amount of water taken
up result particularly in fluctuations in the crimping and dye-
ing properties of the filaments.
Apart from the application of spinning preparations to
filaments by the roller method, it is known that liquid, foam-
able smoothing or stiffening agents can be applied in foam form
to a weft or warp yarn through a slot. A similar process is
also described in our own earlier Canadian Patent Application
200,255 filed May 17, 1974, Keinrïch et al. However, it has
been found that, when preparations are applied through a slot,
particularly at high filament speeds, the previously described
disadvantages are not completely avoided and the amount of
preparation applied is still subject to fluctuations. The re-
sulting increase in the size of the packages and the irregular-
ities occurring in texturing and dyeing make it necessary to
optimise already known preparation methods.
Accordingly, the object of the invention is to avoid
the above mentioned disadvantages and difficulties~
It has been been found that emulsions and, quite
generally, preparations or liquid systems, can be uniformly
applied in dosable quantities to filaments travelling along a
linear path, providing the liquid systems are applied, optionally
in foamed form to the filaments through a curved slot by the
one-~ay technique.
Accordingly, in a broad aspect, the invention resides
in a process for the quantitative application of liquid systems
in a thin layer to filaments moving uniformly along a linear path
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by the one-way technique using a forced dosage unit in which the
liquid introduced per unit of time is quantïtatively taken up
by the filaments, wherein the filaments are guided past at least
one slot which lies along a concave curve from end to end, said
filaments being uniformly distri~uted over the entire width of
the slot, whereby said filaments are brought into contact with a
liquid issuing from the slot.
In a further ~road aspect, the invention resides in an
apparatus for th.e quantitative application of liquid systems in
a thin layer to filaments moving uniformly along a linear path
by the one-way technique using a forced dosage unit comprising,
a liquid container having an inner compartment, an inlet for
feeding liquid into said container, a horizontally disposed slot
in a wall of said container, the outer surface of said wall being
concave in the horizontal direction parallel to the length of
said slot whereby said slot lies along a concave curve from end
to end with a radius of 20 to 200 mm, said slot having a length
of between 10 and 250 rnm, and an outlet height of between 0.1
and 1 mm, and means for guiding said filaments past said sl\t ~ ~ :
.~20 so that they will ~e uniformly distributed over the entire wid-
~of said slot.
The process is suitable for the application of pre-
parations to natural or synth.etic filaments at all the speeds
normally used in production or after treatment processes.
According to a preferred embodiment the filaments are guided
past a height-adjusta~le slot which is Ool to 1 mm tall and which
is curved or provided with partial curves and which is adapted to
the width of the sliver or to the number of filaments. The
filaments are contacted with.an optionally foamed liquid issuing
from the slot, the linear speed of the issuing liquid being
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determined by -the slot height at a predetermined flow rate per
unit volume and the dose of liquid introduced in each short time
interval being quantitatively taken up by the filaments.
If the liquid applied i5 an emulsion, the residence time
of the liquid in each unit volume of the apparatus must be
appreciably shorter than the average life of the emulsion.
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~ ilaments of organic or inorganic, s~nthetic or natural
materials are suitable for preparation by the process according
to this inven-tion. For example, filaments o:E po:Lyamides, poly-
esters, polyacrylonitriles, polyolefins, carbon, glass, asbestos
or aluminium oxide can be successfully coated with a series of
known preparations by the process according to the invention.
Examples of such preparations are lubricants such as mineral oils,
vegetable and animal oils, natural and synthetic waxes ancl ester
oils (fatty acid esters or dicarboxylic acid alkyl esters~;
antistatic agents such as salts of partial esters of phosphoric
acid with fatty alcohol polyglycol ethers or alkylphenol poly-
glycol ethers, and sulphuric acid esters of the above-named
ethylene oxide adducts; emulsifiers such as ethylene oxide and/or
propylene oxide adducts of fatty alcohols, fatty acids and fatty
amines; wetting agents, such as sulphosuccinic acid esters and,
optionally, additions of bactericides such as o-phenylphenol and
_-chloro-m-cresol.
The process according to the invention has proved to be
particularly advantageous in the production of filaments from
polyamides and polyethylene terephthalate. Depending on the
particular production process or after-treatment process, it is . ~.
possible in accordance with this invention to apply spinning
preparations and brighteners at virtually any stage in the pro-
duction of polyamide or polyethylene terephthalate filaments.
Thus, the preparation can be transferred to the. filaments in
foamed or non-foamed form either in the spinning tube itself or
directly after Ieaving the spinning tube, after stretching,
before and after texturing, after fixing in the case of mono-
filaments and after dyeing and before or after -twisting or wind-
ing with all filaments. In spite of the very high. speeds used
in these processes, the liquid systems are quantitatively applied
uniformly and in exactly measured quantities.
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The process according to this invention is suîtable for
applying foamed and non-foamed liquid systems, preferably
emulsions, to filaments immediately after their production pre-
ferably either in the spinning tube itself or im~ediately after
leaving the spinning tube.
In -the production of polyamide-6 filament, it is pre-
ferred to apply from 1 to 7~ by weight based on the substrate,
of a spinning preparation.
On drawings which illustrate embodiments of the invention,
Figure 1 is a cross section oF one embodiment of
apparatus in accordance with the invention;
Figure 2 is a cross section of another embodiment o
the apparatus in accordance with the invention;
Figure 3 is a cross sectional detail of the outlet slot;
Figure 4a is a plan view of blocks defining the slot
outlet;
Figure 4b is a plan view of an alternative form of
blocks defining another slot outlet embodimentj
Figure 4c is a plan view of a further form of blocks
defining a further slot outlet embodiment;
Figure 5 is a pictorial view of liquid applying appar-
atus;
Figure 6 is a pictorial view of a preferred slot con-
struction; and
Figure 7 i9 a top view of a slot and thread guide.
Figures 1 to 6 show technical embodiments for coating
filaments with a preparation by the process according to the
invention. In Figure 1, a liquid is delivered under pressure
through a feed line 3 into a supply chamber 4 which opens into
a slot 2, the ou-tlet opening of which is situated in a wall of
the liquid container 9, whose outer surface ls concave when
viewed from above in Figure 1 and in a d;rection parallel to
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the longitudinal dimension of the outlet opening of the slot.
This arrangement of the slot provides for improved guiding of
the filament on the preparation unit and, at the same time for
uniform application of the preparation to the filaments.
Accordingly, the invention also relates to an apparatus
for carrying out the process according to the învention, which is
distinguished by the fact that an inner compartment 4 of a
liquid container 9 equipped with a feed 3 for a liquid, opens
into a horizontal slot, the outlet opening of which is situated
in a wall of the liquid container 9 whose outer surface i5 con-
cave when viewed from above in Figure 1 and in a direction
parallel to the longitudinal dimension of the outlet opening
of the slot.
A curved guide 20, preferably made of the same
material as the
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blocks 10 c~nd 11 defining the slot 2, can be arranged about 10 to 30 centi
metres parallel to and above the outlet opening of the slot 2, its curvature
being in the same direction as the curvature of the slot ~see Fig. 7).
m e radius of curvature of ~he guide is such that, in the prepara-
tion of slivers, as uni~orm a distribution of th0 individual filaments as
possible is achieved over the overall width of the slot, and the filaments
are prevented from running over or behind one another. The concave opening
on the outlet side of the slot 2 is 0.1 to 1 mm tall. For slivers, it is
about 10 to 250 mm wide. The radius of curvature amo-mts to 20 to 200 mm.
If the liquid to be applied is in the form of a foam, the apparatus
according to the invention can be modified in such a way that a gas feed line
5, opens into the inner compartment 4 of the liquid container 9 by way of a
porous filter member composed of frit 6. However, the foam can also be pro-
duced elsewhere and fed to the coater.
As shown in Figs. 1, 2 and 5, the outlet opening of the slot 2 is -
preferably defined by two prism-shaped blocks 10 and 11 arranged mutually
parallel and above one anothcr~ their outlet-side surfaces parallel to the
length of the slot and having a concave curve. The material for the blocks
10 and 11 is a wear-resistant, hard, smooth or rough material. The blocks
10 and 11 preferably consist of sintered ceramics, nitrides, carbides, oxides
or hardened stainless steel. Silicon carbide, aluminium oxide, chromium
oxide or wear-resistant non-rusting steels, for example so-called tool steels,
are particularly suitable for the blocks 10 and 11 and for the guide 20.
The frit 6, which is used to introduce a gaseous medium through the
inlet 5 into the supply compartment 4, is preferably made of perfluorina~ed
polyalkylene. A gear pump is used for delivering the emulsion (dosing) into -the supply compartment, the inner wall of the supply compartment ~ being in
~he form of a plane inclined towards the slot in order to avoid dead zones. ;The advantages of forced dosing are that dosing is independent of viscosity
and that concentrated emulsions can be applied with reproducible results.
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As shown in tho drawing, the frit 6 can be situated in the liquid
container as shown in Figs. 1 and 2, although it can also be built into the
feed line 5 outside the supply compartment 4. Non-wl~tting or substantially
non-wetting frits ~e.g. silicone rubber, perfluorina~ed polyethylene) are
pref0rred. The size of the frits used is governed by the throughput of the
gaseous medium ~for example air). The smaller the ratio of gas throughput to
frit surface, the finer the foam formed.
In Fig. 1, a bundle of filaments or a single filament 1 travels
past a slot 2 made of ceramics material. A liquid, for instance an emulsion,
is delivered to the apparatus through the inlet 3 and is then foamed in the
foaming compartment 4 by a gaseous medium introduced through the inlet 5 and
the frit 6. The reference 7 denotes a rubber seal and the reference 8 a
cover plate for the inner or foaming compartment 4. The reference 9 denotes
the liquid container or the housing for the foaming compartment. F'or one-way
liquid application, the apparatus according to the invention shown in Fig. 1
can also be made without the gas inlet 5 and without the frit 6.
Fig. 2 illustrates another embodiment of the apparatus according to
the invention ~one-way foam coater). The references 1 to 8 in Fig, 2 have
the same meanings as in Fig. 1.
Fig. 3 shows the dimensions of the slot. The references 1, 4 and
8 have the same meaning as in Fig. 1. The references 10 and 11 denote con-
cave blocks which define the curved slot 2. The object of the guide 20 is
to improve guiding of the filament.
The section
A characterises the slot height and amounts to from
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0.1 -to 1 mrn,
B is from 1 to 10 nml,
C has a length of 1 to 100 mm"
¦ D is the slot length and is from 1 to 100 mm.
Fig 4a is a plan view of the bloc~;s 10 and 11 defining
the curved slot 2 in the direction of filamentl-travel.
The interval E is 1 to 2 mm wide for a linear slot wid-th F
(cord length) of 30 to 40 mm. These two distances determine
the curvature of the slot.
Fig 4b shows an interrupted slo-t in which the liquid or
the foam is fed through the component slots 1~
The partitions 12 can be used as llow guides.
i Fig. 4c shows a slot with partial or individual curves
16 into which open the channels 15 which can also be laterally
defined by flow guides 13 as in Fig. 4b. The radii of curvature
of the individual curves are from 0.05 to 2 mm and their width
G from 0.1 to 3 mm.
Fig. 5 is an overall view of an apparatus suitable for
applying liquid. The references have the following meanings:
1 20 1 = filament
1 2 = slot (outlet opening)
10, 11 = prism-shaped or similarly shaped blocks concave on one
side.
3 = liquid inlet.
17 = spring closure
19 = the apparatus ean be moved (adjusted) in the direction
i of these arrows by a conventional mechanism.
Fig. 6 shows a preferred embodiment of the apparatus
according to the invention in which the slot is defined by
lateral guide eages 18. The edges are about 0.5 mm long.
Fig. 7 is a view from above in the direction of the
bundle of filaments, showing how the threads are guicled by me~ns
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of the guide 20 and the cur~atue of the slot. 'l~e reference l
~enotes the :~ilaments.
~ le poss-ibility oI fitting the coating unit to the
mounting base by means of a spring closure represents another
advantage of the appara-tus according to the invention. A~lother
major advantage is the adjustability of the coating uni-t
relative to the bundle of filaments or -the single filament.
This means that the coating unit can be brought up to the
bundle of filaments.
The fcllowing Example~ are to further illu~trate the
invention without limiting it.
EX~MPLÆ 1
A polyamide-6 filament yarn stretched to a denier of
dtex 940/f 140 was drawn at a spinning take-off speed of 500
m/minute directly past the slot of a~one-way liquid application
-unit o~ the l~ind shown in ~igs. l, 5 and 6 and was propared
with a 24% oil-in-water emulsion (dyhamic viscosity: 17 cP at
20C). T,he application slot with circular curvature had a
linear width (cord length~ of 40 mm, a radius of curva-ture
o~ 134 mm, a height of 0.5 mm and a length of 4 mm. The slot
was formed by 2 curved pieces of carborundum (SiC). The
emulsion was forced -through the application slot by a gear
pump (spinning pump: o.6 cc. per revolution)r The individual
fibr~s of the bundle of fibres were prepared immediately
adjacent the slot and too~ up the emulsion quantitatively
and uniformly. Chemical analysis of the preparation content
f the filament yarn (5 g sample of each 40 kg package)
over a period of 4 wee~s showed an oil content of (1.26 + 0.02) %
and a water content of (3.37 ~ 0.08)%. The stretching of
the resulting filament yarn was clcarly better than that of
comparable material prepared with a roller. The specific
tensile strength was consistently above 80 Rkm roller: 70 to
75 Rkm). The proportion of low quality samples was 0.
(roller l.5%).
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E~LE 2
, A polyamide-6 filament yarn stretehed to a denier o~ dtex
! l~70/f 70 was drawn at a spinning take-of~ speed of 1000 metres/
minute directly past the slot of a ~ne-way liquid applieation
unit of the kind shown in ~igs. 1, 5 and 6 and was prepared
I with a 27~ oil-in-water emuslion (dynamie viscosity: 41 cP ~t
¦ 20C). The applieation slot with a circular curvature had
a linear width (cord length) o~ 25 mm and a radius of curvature
of 78 mm, a height of 0.25 and a length of 6 mm. The slot was
defined by two curved pieces o~ A1203. Chemical analyses o~
the amount of pxeparation applied to the ~ilament yarn of
eaeh package over a period of 6,weeks showed (1.15 1 0.02 )~
of oil and (2.80 ~ 0.09)% of water.
In spite of the high spinning take-off speed, th0 ~10 k~
paekages were entirely satisfactory in strueture whereas 40 lcg
paekages prepared with a roller under otherwise iden-tieal
; eonditions underwent a marked inerease in size (approximately
10 em in the axial direetion on a Ilanged bobbin with a winding
width of 44.2 cm, whieh is placed with axis vertically arranged
on one flange whilst the other flange is removed). After
stretching on a Rieter stretch-twisting machine speciIie tensile
strengths in the region of 90 Rkm were obtained.
EX~MPLE 3
A polyamide-6 filament yarn stretched to a denier of
1 25 dtex llO0/f 63 was drawn at a spinning take-o~f speed of
580 m/minute directly past the slot of a one-way foam
application unit of the kind shown in Fig. 2 and was prepared
with a foamed 20% oil-in-water emulsion (dynamic visc09i ty : 9 eP
at 20C). The emulsion was ~oreed into the application uni-t
(756 cc/h) above the capillary system by means of a ~eared pump
(o.6 cc per revolution). The eapillary system consisted o~ a
2 mm thick frit made o~ polytetrafluorethylene (average pore ~-
Le ~ 15 357 10
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diameter 30 ~Im) with a useful surlace area of 12 cm2
Filtered air was blolYn through the :Erit (6 l/h under nor~al
conditions). The foam produced hacl a very fi~e, uniform
structure ~cell diameter ~ 0.5 mm). The slot system was
the same as in Example 1. C,hemical analysis of the amount of
¦; emulsion applied to the filaulent yarn of the package over a
period of 4 weeks showed (1.00 + 0.02 )~ of oil and (2.69 + 0.07)%
of water. The filament yarn thus prepared was stretched and
textured by the brake chamber process. Th8 filament travelled
well, and hardly any filament breakages and stops occurred.
; Uniformity of texturing and dyeing were clearly better -than
those of corresponding material prepared by the roller method.
EXAMPL~ 4
_ _
A polyamide-6 filament yarn stretched to a denier of
dtex 2800~f 210 was drawn directly past the slot of the
one-way foam application unit described in Example 3 at a
spinning take-off speed of 158 m/minute and was prepared with
a foamed 30% oil-in-water emulsio~(dynamic viscosity: ~5 cP at
1 20C). The yarn thus prepared was s-tored in cans. The oil
¦ 20 content of the yarn was around (1.69 + 0.02)%, the water
content amounted to (3.51 ~ 0.09)~0. A very strong, coarse
filament yarn of up to 33,000 dtex was prepared by doubling
the yarn from several cans followed by stretching. In
relation to comparable material prepared by the roller method,
(in which context it should be pointed out that only fairly
thin emulsions could be safely applied with the roller ( G 24%
oil)~ a higher uniformity of application was found, as reflected
in an, on average~ 5 ~km higher tensile strength and, in
particular, in a very small number of filament breakages
(1 per 100 kg).
Ex~MpLE 5
A four~strand polyamide-6 filament yarn stretched to a
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Le A 15 357 11
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denier of dtex 4~/f 10 was drawn in past the interrupted slot
of a one-way liquid application unît of -the kind shown in Figs.
1 and 4c at a spinning take-ofl speed oi` 1200 m/minute and
was prepared with a 12.5% oil-in-water emulsion ~dynamic
5 viscosity: 1.8 cP at 20C). The radius of curva-ture of the
I semi-circular slot se~ments at the rear end of the prism-like
l filament-guide grooves was 0.25 mm. The slot sys-tem was formed
from A1203 sintered ceramics. Below each slot segment (in the
direction of filament travel), a thin~ stable localised
emulsion Iilm, through which the filamen-t was drawnl was
formed on the sintered ceramics in the filament guide groove.
~ Emulsion was fed to the slot sy$tem by forced delivery using
; I a gear pump (spinning pump: 0.3 cc per revolution) and before the slot system was guided in 4 equal component streams to
¦ 15 each of the 4 slot segments by flow resistances (recta~gular
channels: 40 mm long~ 0.5 mm deep, 0.3 mm wide). Analyses of
the amount of preparation on the threads produced the following
~¦ results:
a) the average differences f~om?filament to filament at the
same time showed deviations of ~ 2~o for oil and water;
b) the differences in application in one and the same filament
dependent on its length or on the spinning time amounted to
¦ 2% ~or oil and to ~ ~% for water.
In the case of the oil values, the deviations corresponded
1 25 to the inaccuracy o~ analysis.
The filaments were stretched and friction-textured by the
i false~twist process The uniformity of crimping and dyeing
I was clearly better than that of comparison material prepared
by the roller method.
~1 -30 EXAMPLE 6
A polyethylene terephthalate filament yarn stretched to a
denier of dtex 167/ f 34 was guided directly p~t the slot
Le A 15 357 12
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system of a one-way liquid application uni-t of the kind shown
in Figs 1 and 4c at a take-off speed of 1300 m/minu-te.: The
same application unit as in ~ample 5 was used. The spinning
preparation had an oil concentration ol 20~o, The filament
yarn of all the paclcages produced from the 4 threads
showed high uniformity o~ application over a period of 5
' weeks bo-th from filament to filament and in each individual
- i ~ilament as a function of time. The speed of the gear
pump was adjusted so that an average oil application of
0.75~ by weight, based on the fibre mass, was achieved.
I A value o~ ~0.74 ~ 0.02)% was found. The filament yarn
prepared in this way, wa~ stret~ched and textured by the
fàlse-twist process. The yarn travelled satisfactorily
through the machine. Fluctuations in bulking were
appreciably lower than in material prepared by -the roller
method. Roller preparation at 1300 m/minute resulted in a
very uneven applicatio~ of oil with fluctuations of up to + 20%.
EXAMPLE 7
20 polyamide-6 monofilament yarns with individual
deniers of 400 dtex were continuously subjected after fixing
~ to one-way liquid preparation by the process according to the
¦ inve~tion at a speed of 240 m/minute. The monofilaments
¦ were guided horizontally at intervals of 7 mm from one another.
A unit of the kind shown in Figs. 1 and 4c was used for
application, the monofilaments running in hor~.~tal guide
grooves (16 in Fig. Jlc). Brightening was carried out with a
20% oil-in-water emulsion with the dynamic viscosity of
70 cP at 20C delivered by a gear pump and ~orced through the
~i curved slot segments of the application unit. 2.2% of oil
was applied. The fluctuations in oil application amounted to
+ 0.13~ from monofilament to monofilament, based on the average
oil content of the monofilaments. This brightening process
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! made the monofilaments much sa-fer to process on weaving machlnes
with filament speeds of 600 m/minute than mono~ilaments that
I had been brightened by a roller. In addition, it was readily
'. possible by the process according to~the invention uniformly
to obtain any output of oil re~uested by customers to suit
their machine settings. ~his was not possible with preparation
rollers.
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