EP0134940B1 - Liquid composition, process and apparatus for the sizing of yarns - Google Patents

Abstract

The yarn smoothing liquid composition (11) contains a binder. To be able to effect smoothing in an energy-saving manner and without the customary sizing apparatus, the binder is applied to the yarn with a viscosity of at least 500 mPas and an active substance content of at least 10%, together with a release agent which is incompatible with the binder. The treated yarn can be wound up in the undried state without risk of coils of yarn becoming stuck together. <IMAGE>

Description

The invention relates to a yarn smoothing liquid with a binder used for smoothing as the first component, which is a polymer dispersed in water.

It is known to size yarn as part of the weaving preparation. The term "yarn" in the sense of the invention is understood to mean any thread-like material that is textile, i.e., e.g. Staple fiber yarns, smooth, intermingled and textured filament yarns, made from fiber materials in accordance with DIN 60001, which also include glass, asbestos and ribbon yarns.

Sizing has the particular effect of gluing fiber ends protruding from the yarn. Consequently fiber ends of adjacent threads can no longer wrap around each other. Such brackets would e.g. B. in weaving preparation with parallel threads require that the coherent threads would have to be separated again, which would reduce their strength. When weaving, the shed formation would be made more difficult by the clinging of the fiber ends or would be hindered in such a way that proper work would no longer be guaranteed, particularly in modern weaving machines with small shed angles. In addition, the use of unsized yarn during weaving would result in considerable abrasion and the strength of the yarn would be impaired.

In the conventional sizing process, the sizing liquid is e.g. B. applied to the yarn when passing through the yarn through a trough filled with sizing liquid. The yarn provided with sizing liquid passes through a pair of squeeze rollers or the like, through which the excess sizing liquid is squeezed off and through which sizing liquid is also squeezed into the interior of the yarn. The yarn then goes into a dryer where it is dried using heat and a fan. Only after the yarn has dried is it wound up so that the wound turns of a warp beam, a bobbin or the like do not stick to one another. Especially when working with the highest possible yarn running speeds, the energy expenditure during drying is considerable, especially if the sizing agent has a high proportion of water or solvent, which has to be removed quickly.

When the yarn runs out of the pair of squeeze rollers, some fiber ends stick to the circumference of the roller and the neighboring thread due to the high level of adhesion and are then torn off again. It is not possible to completely switch off the yarn hair, which would be technologically desirable. The drying of the yarn also causes further fiber ends to tear away from the yarn body and to return to their original position, projecting from the yarn, in whole or in part. This means that there are limits to the size, which has an impact especially at high yarn speeds.

From GB-A-659 380 a yarn smoothing liquid with the features mentioned above is known. The polymer is a polyvinyl acetate and in its aqueous solution or dispersion a mineral oil is emulsified together with other substances. As a result of this emulsion, the oil acts as a smoothing agent that reduces sliding friction. The mineral oil is not described as a phase separating agent.

The invention is based on the one hand the object to improve a liquid for yarn smoothing of the type mentioned in such a way that the aforementioned disadvantages are no longer present, but that high thread speeds with low hairiness of the smoothed yarn can be achieved in a simple manner.

This object is achieved in that the binder, as a polymer which is dispersed in water or dissolved in an organic solvent, has a viscosity of at least 500 mPa xs and an active substance content of at least 10% in the ready-to-use state, and that, as a further component, a release agent which phase-separates the binder is available.

It is essential for the invention that, in addition to the binder having the properties described above, a release agent is present which is incompatible with the binder, so that a phase separation takes place, for example, after 0.25 to 24 hours. This phase separation means that yarn threads lying against one another or wound up cannot stick to one another.

The binder contains a surfactant. A surfactant is a surfactant. The surfactant present in the smoothing liquid causes a uniform wetting of the thread and at the same time controls the time after which the binder / release agent dispersion or solution separates and also ensures that the binder is on the thread and the release agent on the outside of the binder layer. Wetting, emulsifying or dispersing agents are preferably used as the surfactant, e.g. Sulfuric acid esters, amine salts, betaines.

The coatable binder component has a film-forming property with a high adhesive strength at a layer thickness of 0.1 mm. The high cohesion present accordingly means that small amounts of liquid are sufficient to achieve the desired smoothing effect if it is ensured at the same time by the applied application process that the binder is essentially only deposited in the outer layer of the thread.

While the known sizes are applied consistently with low viscosities, the viscosity of the binder which can be applied is preferably 1500 to 2000 mPa.s. In this sense, the active substance content of the applicable binder is 15% to 30%. These values of the binding agent of the smoothing liquid show the desired yarn properties combined with the short drying time of the yarn after winding.

The proportion of release agent is so large that the release agent migrates to the film surface when the yarn dries or during binder film formation, so that sticking of yarn turns is avoided. For this purpose, the density of the release agent when applied to the yarn is less than the density of the dispersant dispersing the binder. On the other hand, the HLB number of the releasable release agent is at least 1 greater than that of the binder dispersion.

The following are preferably used as binders: polyacrylates; Polyvinyl compounds based on acetates, alcohols and copolymers; Polyethylene and mixtures of these agents with each other.

As release agents come e.g. in question: mineral oil, fatty acid esters, silicones, paraffin dispersions, ethylene oxide / propylene oxide products.

The separating agent has thread / thread and thread / metal friction recursive properties, so that high thread speeds can also be used in this respect, for example at least 50 m / min, but preferably at 200 to 500 m / min.

On the other hand, the invention relates to a method for smoothing yarn, which is guided and wound as a running single thread or running thread sheet through a device that applies the smoothing liquid. The known methods of this type have the disadvantages mentioned at the outset. In contrast, a prescribed liquid has room temperature or almost room temperature when applied and the treated thread is wound at a speed of at least 50 m / min without thermal drying. It is therefore neither necessary to heat the liquid, nor to use heat or energy to dry the yarn. The distance between the device and a winding device can be small. The device or smoothing therefore takes up little space. In particular because of this and above all because of the high thread speed, the smoothing can also be carried out when drawing or warping, so that a special operation is saved, namely smoothing associated with separate wrapping. The smoothing liquid is applied and thus also wound up in a preferred speed range from 100 m / min to 800 m / min.

Only very small amounts of the smoothing liquid are applied to the yarn, which are significantly smaller than the amounts of sizing liquid in conventional wet sizing processes. The application itself is carried out by methods which allow small amounts to be applied, such as knife coating / splashing, spraying, using a metering nozzle or using foam. This avoids the conventional immersion process, in which the yarn runs through a liquor. Subsequent to the application, the agent applied is spread so that the yarn circumference is covered on all sides by a film and fibers protruding from the yarn jacket are pressed into the film and held there.

In one embodiment of the invention, the required amount of the smoothing liquid or its binder and release agent component is applied in one or more stages, and in the case of multi-stage application the smoothing liquid is applied as a finished component mixture or in the order of binder component with surfactant and release agent component, wet on wet. If the release agent component of the smoothing liquid is applied wet in wet after the binder has been applied, the film formation rate or drying can be accelerated, since the release agent is already on the outside of the binder due to the subsequent application and a time-demanding phase separation can be avoided in whole or in part.

On the other hand, the invention relates to a device for carrying out the above-described methods. In order to apply the smoothing liquid and / or its release agent component, according to the invention, a transfer roller for supplying an application roller is provided in a bath containing the agent to be applied, and it has a spreading device arranged downstream in the thread running direction. The design of the application device with rollers is particularly suitable, since conventional components can be used here which allow precise metering even of small application quantities.

Fig.1

eine schematische Darstellung einer ersten Auftragsvorrichtung, bei der Auftragen der Glättungsflüssigkeit und Verstreichen getrennt voneinander erfolgen,

Fig.2

eine schematische Darstellung einer weiteren Auftragsvorrichtung, bei der Auftragen der Glättungsflüssigkeit und Verstreichen kombiniert erfolgen,

Fig.3

eine dritte Vorrichtung, bei der weitere Modifizierungen vorgenommen sind und

Fig.4,5

eine Verstreicheinrichtung.

The invention is explained with reference to the drawing. It shows:

Fig. 1

1 shows a schematic illustration of a first application device, in which application of the smoothing liquid and spreading take place separately from one another,

Fig. 2

1 shows a schematic representation of a further application device, in which application of the smoothing liquid and spreading take place in combination,

Fig. 3

a third device in which further modifications have been made and

Fig. 4.5

a spreading device.

• Variante 1: Die Tröge I, II enthalten beide sowohl Bindemittel als auch Trennmittel in gleichem oder unterschiedlichem Mischungsverhältnis.
• Variante 2: Der Trog I enthält Binde- und Trennmittel, der Trog II nur Trennmittel.
• Variante 3: Der Trog I enthält nur Bindemittel, der Trog II Bindemittel und Trennmittel, oder nur Trennmittel.
• Variante 4: Die Verstreicheinrichtung II/S ist nicht vorhanden. Der Trog II enthält nur Trennmittel, Der Trog I nur Bindemittel oder Binde- und Trennmittel gemeinsam.

The device of Figure 1 has two troughs I, II and downstream in the thread running direction F are arranged behind each trough I, II spreading devices I / S and II / S. In each trough I, II there is an immersion roller 10, each of which is immersed in a bath 11. The plunger rollers 10, on the other hand, touch a group of threads 12 or a corresponding single thread. The dipping rollers 10 are driven in rotation in the direction of the arrow, specifically by being carried along by the thread sheet 12 or by a separate rotary drive. The rotation of an immersion roller 10 takes liquid out of the bath 11, which forms a film 13 on the immersion roller 10, which is partially transferred to the yarn or the thread sheet 13. The thread sheet 13 then runs over the spreading devices I / S, II / S, the fibers still protruding from the package press on and, if necessary, press some of the liquid transferred to the yarn inside the yarn. The following process variants can be carried out with the prescribed device:

• Variant 1: The troughs I, II both contain both binders and release agents in the same or different mixing ratio.
• Variant 2: The trough I contains binding and release agents, the trough II only contains release agents.
• Variant 3: The trough I contains only binders, the trough II contains binders and release agents, or only release agents.
• Variant 4: The spreading device II / S is not available. The trough II contains only release agents, The trough I only contains binders or binders and release agents together.

1 can therefore be used to carry out all the process variants which are required for applying the smoothing liquid with the desired small layer thickness.

In the device of FIG. 2, the dipping rollers 10 or an application roller 14 themselves form the spreading device, so that only the troughs I, II are required for yarn smoothing. 1, with a film 13 conveying liquid from the bath 11 onto the thread sheet 12, the application roller 14 in the trough II is supplied with a film 13 'by a transfer roller 15 which is comparatively thin.

• Variante 1: Der Trog I enthält entweder nur Bindemittel oder Bindemittel und Trennmittel zusammen. Der Trog II enthält Trennmittel und seine Auftragswalze 14 trägt dieses Trennmittel auf und verstreicht gleichzeitig.
• Variante 2: Der Trog I enthält nur Bindemittel oder Binde- und Trennmittel gemeinsam. Der Trog II enthält Binde- und Trennmittel zugleich und die Auftragswalze 14 arbeitet wieder zugleich als Verstreicheinrichtung.

The device of FIG. 2 is preferably used to carry out the following process variants:

• Variant 1: The trough I either contains only binders or binders and release agents together. The trough II contains release agents and its application roller 14 applies this release agent and passes at the same time.
• Variant 2: The trough I only contains binders or binders and release agents together. The trough II contains binding and separating agents at the same time and the application roller 14 again works at the same time as a spreading device.

Of course, three- or four-stage processes are also possible. In addition, the trough I need not be used only in connection with an immersion roller. The trough I or only the trough I can also be equipped as the trough II in FIG. 2, namely as a godet with a transfer roller.

Fig. 3 shows a trough I with a bath 11, which consists of a binder, optionally a surfactant and a release agent. The application takes place with an immersion roller 10, which works together with a stripper 16 in order to keep the film 13 consisting of smoothing liquid thin for the thread sheet 12. Downstream of the thread running direction F is a spreading device 17, consisting of a rotary driven roller which interacts with a cleaning roller 18. The cleaning roller 18, like the roller of the spreading device 17, is a brush roller. However, other configurations are also conceivable, preferably smooth or groove-free contact surfaces for the thread sheet 12 Groove-free contact surfaces are preferably available on all dipping or application rollers in order to reduce thread closure.

Yarn hairiness can be decisively reduced with the means described above, namely by at least 50%, measured with a Shirley hairiness analyzer, with a test length of 4 mm. The maximum tensile strength of the yarn does not change due to the smoothing.

The yarn smoothed with the above-described agents dries in the wound state and does not stick together. The yarn threads do not stick together, so that after they have been wound up at speeds of 0.5 m / min to 1500 m / min, they can be pulled off tangentially or overhead again without problems. The agents applied to the yarn are easily soluble, in particular water-soluble, and can therefore be washed out of the finished fabric in the usual way. Deposited excess smoothing liquid forms a soft, non-sticky film on metal surfaces due to the release agent component, which is easy to remove from the warping system or from the weaving machine.

Smoothing is in particular a warp-proof treatment of yarns, which can be used as an alternative to the sizing of fiber or filament yarns or intermingled smooth or textured filament yarns. Passing through a liquid-filled trough can be avoided. As a result, there is no excess liquid application to or into the yarn and no squeezing device is required to remove excess application.

4, 5 show a special spreading device which is preferably used because of its all-round effect. A comb 19 is present vertically to the thread running direction F and engages between the threads 12, only one of which is shown. The comb 19 thus keeps the threads 12 at a distance from one another. Parallel to the comb 19 there is a doctor rod 20 on the inlet side and a rod 21 on the outlet side. The non-rotatably or rotatably mounted rods 20, 21 are parallel to the comb 19. The thread family runs under the inlet rod 20 into the comb 19, but over the outlet rod 21, so that a combing effect on all sides by the comb 19 and the coating rods 20, 21 is exercised on each individual thread 12. The device can also serve to guide the thread, which is also the case in particular if the family of threads enters the comb at any angle deviating from 90 ° to the comb axis.

For warping the threads of a group of threads to be wound up, polyester filament threads of dtex 50 f 18 are used, for example, and are treated according to the following with the following:

Example 1:

Bindemittel:

8 - 10% Polyvinylalkohol
8 - 12% Polyethylenoxid, verseift

Trennmittel:

3 - 4% Diol
4 - 6% Mineralöl

Der Rest zu 100% Wasser
oder

Binder:

8-10% polyvinyl alcohol
8 - 12% polyethylene oxide, saponified

Release agent:

3-4% diol
4 - 6% mineral oil

The rest 100% water
or

Example 2:

Bindemittel:

8 - 10% Polyvinylalkohol
8 - 12% Polyethylenoxid, verseift

Trennmittel:

3 - 4% Diol
4 - 6% Mineralöl

Tensid

5 - 8% Alkoholoxethylat und Alkylphenoloxethylat

Der Rest zu 100% ist Wasser.

Binder:

8-10% polyvinyl alcohol
8 - 12% polyethylene oxide, saponified

Release agent:

3-4% diol
4 - 6% mineral oil

Surfactant

5 - 8% alcohol oxyethylate and alkylphenol oxyethylate

The rest is 100% water.

Claims (12)

1. Yarn sizing liquid comprising a binding agent as a first component serving to smooth the yarn, characterised in that the binding agent is a polymerisate dispersed in water or dissolved in an organic solvent, and in the application state has a viscosity of at least 500 mPa x s and at least 10% of active material, and in that a separating agent which is phase-separating in relation to the binding agent is provided as a further component.
2. Liquid according to claim 1, characterised in that the binding agent includes a surface active agent.
3. Liquid according to claim 1 or 2, characterised in that its binding agent component with an applied 0.1 mm thickness layer has film-forming properties with high adhesive force.
4. Liquid according to one of claims 1 to 3, characterised in that the viscosity of the applied binding agent in the applied state is 1,500 to 2,000 mPa x s.
5. Liquid according to one of claims 1 to 4, characterised in that the active material of the binding agent as applied amounts to 15% to 30%.
6. Liquid according to one of claims 1 to 5, characterised in that the density of the applied separating agent is smaller than the density of the dispersion means dispersing the binding agent.
7. Liquid according to one of claims 1 to 6, characterised in that the HLB count of the applied separating agent is about at least 1 more than that of the binding agent dispersion.
8. Liquid according to one of claims 1 to 7, characterised in that the separating agent has properties reducing yarn/yarn friction and yarn/metal friction.
9. Liquid according to one of claims 1 to 8, characterised in that the binding agent is 8 to 10% polyvinyl alcohol and 8 to 12% polyethylene oxide, saponified; the separating agent is 3 to 4% diol and 4 to 6% mineral oil as well as, if required, as surface active agent, 5 to 8% alcohol oxy-ethylate and alkyl phenyl oxy-ethylate, with the remainder up to 100% being water.
10. Method for the sizing of yarn which is guided through an apparatus which applies sizing liquid thereto, the yarn being a running single yarn or running yarn bands and being wound after treatment, characterised in that a liquid according to one of claims 1 to 9 is applied at room temperature or close to room temperature and that the treated yarn is wound at a speed of at least 50 metres per minute without thermal drying.
11. Method according to claim 10, characterised in that the application of the necessary amount of sizing liquid or its binding agent and separating agent components is effected in one or more stages, and in that in the case of multi-stage application the sizing liquid is applied as a finished component mixture or in the sequence of steps binding agent components with surface active agent and separating agent components are applied wet-on-wet.
12. Apparatus for carrying out the method according to claim 10 or 11, characterised in that, for the application of the sizing liquid and/or its separating agent components, a transfer roller (15) is provided which rotates in a bath (11) carrying the means to be applied to deliver said means to an application drum (14), and in that the apparatus includes a spreading device (I/S, II/S) positioned thereafter in the direction (F) of yarn movement.

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