EP2173931B1 - Fibrefill fibre having improved opening characteristics, production and use thereof - Google Patents

Abstract

The present invention relates to a process for producing a cellulosic fibre, in particular a lyocell fibre which has improved opening characteristics and therefore is particularly useful for blending with feathers, in particular with down, to such a fibrefill fibre and to the use of this fibrefill fibre in mixtures for bedding and clothing.

Description

The present invention relates to a method for producing a cellulosic fiber, in particular a lyocell fiber, which is particularly well suited for mixing with feathers, in particular with down, due to its improved opening behavior, such a filler fiber and the use of this filling fiber in blends, as well as bedding and Clothing filled with these blends.

As filler fibers blended with down and feather, short cut fibers of melt-extruded synthetic polymers such as polyester, polylactic acid and others are known and widely used.

Cellulosic fibers, in particular the solvent-spun fibers designated by the generic name Lyocell from BISFA (The International Bureau for the Standardization of Man Made Fibers) have been known for a long time and have been produced on an industrial scale for years. In the production of lyocell fish, the solvent used is a tertiary amine oxide, in particular N-methylmorpholine-N-oxide (NMMO). Also suitable as solvents are ionic liquids.

The solution of cellulose is usually extruded in this process by means of a molding tool and thereby formed. The shaped solution passes, for example, in a so-called dry-wet spinning process via a Luftspaft in a precipitation bath, which is obtained by precipitation of the solution, the shaped body. The molding is washed, and if necessary, dried after further treatment steps. A method for producing Lyocellfasern is z. B. in the US 4,246,221 described,

WO 94/28220 relates to a process for crimping cellulosic filaments prepared by a dry-wet spinning process by means of a buffing chamber crimping to obtain an adhesion similar to naturally crimped natural fibers.

WO95 / 24520 discloses a crimping process of lyocell fibers in the wet state by means of a stuffer box to obtain a permanent crimp. These fibers are particularly suitable for use in filters.

It has also been proposed to use lyocell fibers as filler fibers in the form of nonwovens in quilts and as balls in pillows. So are Belapleisweise in WO 99/16705 described as suitable Füllfasertypen crimped lyocell staple fibers for nonwovens and balls. However, this publication does not give any information on the fiber titer, the cut length of the fibers or surface treatments. On the opening behavior of the fibers and resulting problems is the WO 99/16705 not a.

In the WO 2004/070093 A2 lyocell fibers with a denier of 6.7 dtex and a cut length of 11 mm are proposed as mixing partners for feathers and down. The mixture of lyocell and feathers or down is done in a wet mixing process. The opening behavior of Lyocell fibers and related problems contains the WO 2004/070093 A2 no hints.

In the WO 2004/023943 In addition, lyocell fibers in the titer range of from 0.7 to 8.0 dtex and a cut length of from 5 to 100 mm are described in detail for use as filler for disposable quilts consisting of pure lyocell or blends with other, preferably biodegradable synthetic fibers. Lyocell as a blending partner for feathers and down is only suggested incidentally, without pointing to the associated processing problems or even revealing a solution to such problems.

From the WO 2005/007945 is the use of lyocell staple fibers with a value of the ratio of denier (in dtex) to cut length (in mm) of 0.10 or more known as fill fiber for blankets, upholstery, pillows, Mätratzen or fleece for upholstered furniture. The use of such fibers for mixing with fibers of other Fasergattungen or with down and feathers is described there.

The production of known from this prior art fibers for down blends is done, for. B. according to EP 797 696 in that the spun filaments are cut into staple fibers immediately after being spun in the wet state and then fed as a nonwoven to a continuous after-treatment. After washing to remove residual NMMO and finishing, the fibers are dried and packed into bales in a press to achieve pressures of up to 220 bar. This type of fiber preparation, aftertreatment and packaging is similar to that of similar fibers that are later used for applications in yarns or nonwovens. A lower compression is not possible for logistical and economic reasons.

However, processors of down and feathers do not generally have the usual additional opening equipment otherwise used in textile manufacturing. The synthetic fibers such as polyester, which are widely used as compound fibers, are easy to open, so that no aggressive opening units have to be used for processing such fibers. The majority of the down and feathers is processed in the dry state, with aggregates fans and blowpipes for Opening, mixing and transporting are used. Now, if the lyocell fibers known from the above-mentioned process are used as the mixing partner, then the fibers are poorly opened due to the strong compression in the bale. In this case, larger structures of unintentionally solidified fibers can get into the subsequent processing machines and destroy their sensitive parts. A homogeneous mixture with down and feathers is not possible with these fibers. Also the WO 2005/007945 does not address the problem of inadequate opening possibilities of a commercially pressed fiber bale with the equipment available at down processors.

Task:

Compared to the known prior art, the object of the present invention therefore was to provide a fiber that can be opened without the application of the usual in the textile industry opening units and then processed into a homogeneous mixture with down and feathers.

A further object was to provide a method by means of which a fiber can be produced which can be opened without the use of the opening units customary in the textile industry and subsequently processed to a homogeneous mixture with down and feathers.

solution

This task could be solved by a cellulosic filler fiber with a Einzeifasertiter from 0.7 to 6.0 dtex, preferably 0.8 to 3.0 dtex, which produced a crimping in a stuffer box with a sheet count of at least 18 sheets / 10cm and has a finishing layer. These fibers have an excellent opening behavior with simple aggregates even after strong compression in a commercially available fiber bale, which can be determined in the practical, so-called blowbox test.

Fibers having a single fiber titer that is significantly less than 0.7 dtex are too fine for their intended use as filler fiber, for example because they do not have sufficient bulkability. Fibers with a single fiber titer significantly greater than 6.0 dtex are too thick and stiff and therefore do not provide a soft filling as required by a product with down and / or feather from the consumer.

The stuffer box crimping took place after the in WO95 / 24520 described method. Surprisingly, it has been found that these fibers have better opening properties than lyocell fibers which were produced by means of the abovementioned nonwoven aftertreatment. In particular, it was surprising that a fiber crimped in a stuffer box could be opened much better than a fiber crimped in a fleece aftertreatment.

It should be emphasized at this point that a fiber crimped in a stuffer box differs significantly from a fiber crimped in a fleece aftertreatment. For example, in one according to the EP 797 696 In the nonwoven crimped fiber permanent crushing sites exist, which are clearly visible in the polarizing microscope. While such nonwoven crimping is advantageous for various textile and other applications, it has the disadvantage of poorer opening performance for the field of the present invention.

The filling fiber according to the invention preferably has a number of sheets of 18 to 50 sheets / 10 cm, more preferably an arc number of 18 to 40 sheets / 10 cm. A lower number of sheets results in too low bulkiness of the filling fiber, while higher than the mentioned numbers of sheets in turn worsen the opening behavior, since more entanglements can occur between the individual fibers.

It also preferably has a finishing layer of from 0.3 to 3.0% by weight, based on the total weight of the finished fiber. While lower finishing requirements lead to a poorer sliding behavior and thus to a poorer opening behavior, higher finishing requirements are on the one hand more expensive due to the higher consumption of chemicals, leave too wet or greasy feel of the fibers and also worsen the opening and further processing behavior.

As an additive for this filling fiber, an amino-functionalized lubricant is particularly preferred. The amino groups in the lubricant significantly contribute to the adjustment of the lubricating behavior which is important for the filling fiber according to the invention, which makes possible the good opening behavior and the necessary bulk. The type of Furiktionalisierung has greater influence on the gliding behavior than the basic substance of the Avivage.

The base substance of the finish are all chemical compounds known for this purpose, for example silicone oils or avivages based on fatty acids. However, a silicone oil is preferred for the present invention, since this is the best permanence. Permanence should be understood here as the ability to remain on the fiber as long as possible, for example even after several washes.

Great influence on the good opening and processing ability of the filling fiber according to the invention has the staple fiber length, also called cut length. Surprisingly, it has been found that filler fibers according to the invention having a staple fiber length between 6 and 20 mm have the best properties. Too large staple fiber lengths lead to more entanglements and thus to a deterioration of the opening behavior. The crimped in the stuffer box fiber cable is in the extended state, d. H. under tension by standard cutting machines, in which the cutting length is previously set fixed cut.

Surprisingly, it has been found that can be determined by the so-called blowbox test, whether a fiber is well suited for use as a filling fiber with a good opening behavior. This is of great importance in ensuring product quality. A poor opening behavior leads to complaints of customers, as these, as already described above with their existing aggregates, the fiber bales not or only insufficiently open and therefore can not process delivered fibers with poor opening behavior. Poorly opened fibers can also lead to damage to the sensitive processing machines of the Füllfaserverarbeiter and thus to recourse claims against the fiber manufacturer.

The larger the blowbox height ratio, the easier it is to open the fiber with the aggregates commonly found in filling fiber processors. The filler fibers according to the invention therefore preferably have a blowbox height ratio between 4 and 15, particularly preferably between 6 and 14.

1. a. Herstellung einer cellulosehaltigen Spinnlösung,
2. b. Verspinnen der Spinnlösung zu einem Faserkabel,
3. c. Kabelnachbehandlung mit Waschen, Trocknen, Kräuseln und Avivieren,

wobei das Kabel in einer Stauchkammer zu einer Bogenzahl von mindestens 18 Bögen/10cm gekräuselt und anschließend geschnitten wird und die geschnittene Füllfaser ein Blowbox-Höhenverhältnis zwischen 4 und 15, bevorzugt zwischen 6 und 14 aufweist.The further object is achieved by a process for the production of a cellulosic filling fiber with a single fiber titer of 0.7 to 6.0 dtex, preferably 0.8 to 3.0 dtex, consisting of the steps

1. a. Production of a cellulose-containing spinning solution,
2. b. Spinning the spinning solution to a fiber cable,
3. c. Cable post-treatment with washing, drying, curling and finishing,

wherein the cable is crimped in a stuffer box to a sheet count of at least 18 sheets / 10cm and then cut and the cut filler fiber has a blowbox height ratio of between 4 and 15, preferably between 6 and 14.

In the process according to the invention, preference is given to using an amino-functionalized lubricant.

The lubricant used in the process according to the invention is preferably a silicone oil.

Decisive for the opening and further processing properties of the filling fiber is also its finishing layer. It should be between 0.3 and 3.0% by weight, based on the total weight of the refined fiber.

The fibers are preferably spun in a dry-wet spinning process, for example one of the known lyocell processes with aqueous amine oxides or ionic liquids as solvent for the cellulose.

The object is also achieved by the use of a cellulosic filler fiber with a Einzelfasertiter from 0.7 to 6.0 dtex, preferably 0.8 to 3.0 dtex, which generates a crimping in a stuffer box with a sheet count of at least 18 sheets / 10cm as well as a finishing layer, as filling material in bedding and clothing.

The cellulosic filling fiber used for this purpose preferably has a blowbox height ratio between 4 and 15, preferably between 6 and 14.

It can be used in combination with down and / or feathers or also in a mixture with polyester, polylactic acid and / or polypropylene. The use in mixture with natural fibers such as kapok or poplar fluff is possible.

Determination of the number of sheets:

The number of sheets is compared with the in WO 95/24520 determined method described.

Blowbox test:

• Die Blowbox ist ein rechteckiger Metallbehälter, der an der Unterseite offen und an der Oberseite mit einem luftdurchlässigen Sieb abgedeckt ist. Die Abmessungen der Blowbox betragen 20 x 15 x 20 cm (Länge x Breite x Höhe, d. h. 6 I Volumen). An der Oberfläche befindet sich ein luftdurchlässiges Metallsieb mit einer Maschengröße von ca. 0,8 mm.

The opening properties that are practically relevant for use as a filler fiber in combination with down and feathers can be tested on a laboratory scale using the method described below, the so-called blowbox test:

• The Blowbox is a rectangular metal container, which is open at the bottom and covered at the top with an air-permeable sieve. The dimensions of the blowbox are 20 x 15 x 20 cm (length x width x height, ie 6 l volume). On the surface there is an air-permeable metal screen with a mesh size of approx. 0.8 mm.

Through the screen, a constant jet of air is introduced by means of a nozzle, which stirs up the fiber. The excess air also escapes through the sieve.

The determination of the opening properties is carried out as follows, and to obtain reliable results, the mean value is always formed from two tests each:

Determination of the initial height:

5 g of a manually extracted from a pressed bale, so not mechanically opened fiber are first according to the BISFA regulations (BISFA booklet "Testing methods viscose, modal, lyocell and acetate, staple fibers and tows", 2004 edition) in the standard atmosphere (20 ° C, 65% relative humidity) conditioned and then gently transferred to a 3000 ml beaker with a diameter of 14.5 cm and measured the filling height.

These fibers are then added to the blowbox. Via a nozzle whose nozzle head is tilted by 45 ° 6 cm from the right edge in the direction of the blowbox center ( Figure 2 ), air is blown in with a cross section of 4 mm at a distance of 1 cm above the screen, whereby the fibers are whirled up and opened. The compressed air flow rate is set to 8.4 Nm3 / h; the nozzle cross-section must be 4mm. The blowing time per application is 60 sec.

Calculation of the blowbox height:

The fibers previously opened with the blow box are then carefully transferred back into the 3000 ml beaker with a diameter of 14.5 cm and the filling height is measured again ( Figure 3 ).

Determination of the blowbox height ratio:

The blowbox height ratio is the quotient of the blowbox height and the initial height.

• Note 1: Keine Öffnung
• Note 5: Die Hälfte der Fasern sind geöffnet
• Note 10: Alle Fasern sind geöffnet
• Abbildung 4 zeigt beispielsweise Fasern mit der Note 9 für die Öffnungsgüte.

In addition, the opening quality of the fibers is assessed visually according to the following clef:

• Grade 1: No opening
• Grade 5: Half of the fibers are open
• Grade 10: All fibers are open
• Figure 4 shows, for example, fibers with grade 9 for the opening quality.

Examples: Example 1 (comparison):

Lyocell fibers with a single fiber titer of 1.7 dtex were formed by the known process by extrusion of a solution of cellulose in aqueous amine oxide, coagulated by a dry-wet spinning process and cut, washed, dried and coated in a prior art nonwoven aftertreatment a silicone oil so that they had a Avivageauflage between 0.8 and 1.2 wt.% Had. A single value can not be specified for this parameter, because even with careful application of the finish, the circulation in the nonwoven fabric varies within certain limits. The fibers were baled on a commercial scale Autefa baler on a production scale. Samples were then taken according to the method described above.

Inventive Examples 2 and 3:

Lyocell fibers with a single fiber titer of 1.7 dtex were formed by extrusion of a solution of cellulose in aqueous amine oxide, coagulated in a dry-wet spinning process and washed in a cable post-treatment, dried, crimped in a stuffer box crimp and with an amino-functionalized silicone oil Type Wacker finish CT96E, so that they had a lubricant deposit between 0.7 and 0.9% by weight. Only then was the cable cut. The fibers were baled on a commercial scale Autefa baler on a production scale. Samples were then taken according to the method described above.

The fibers produced according to the method of the invention show a much better opening behavior than those of the prior art. example 1 2 3 manufacturing fleece Cable curled Cable curled Cutting length [mm] 11 12 20 number of sheets - 20-25 20-25 Blowbox Note 2 6 6 Initial height [cm] 2 2 2 Blowbox height [cm] 6 23 24 Blowbox-height ratio 3 11.5 12

Claims (12)

1. Cellulosic filling fibre with an individual fibre titre of 0.7 to 6.0 dtex, characterised in that it has a crimp produced in a crimping device with an arc number of at least 18 arcs/10 cm as well as a finishing agent layer and a Blowbox height ratio of between 4 und 15, preferably between 6 and 14, whereby the finishing agent layer is made of an amino-functional finishing agent.
2. Filling fibre according to claim 1 which has an arc number of 18 to 50 arcs/10 cm, preferably from 18 to 40 arcs/10 cm.
3. Filling fibre according to claims 1 and/or 2 which has a finishing agent layer of 0.3 to 3.0 weight percent, in relation to the overall mass of the finished fibre.
4. Filling fibre according to claims 1 to 3 whereby the finishing agent is a silicone oil.
5. Filling fibre according to claims 1 to 4 which has a staple fibre length of between 8 and 20 mm.
6. Process for the production of a cellulosic filling fibre with an individual fibre titre of 0.7 to 6.0 dtex, comprising the following steps:

   a) Production of a spinning solution containing cellulose,

   b) Spinning of the spinning solution to a fibre tow,

   c) Post treatment of tow by means of washing, drying, crimping and finishing,

   characterised by the fact that the tow is crimped in a crimping device with a number of arcs of at least 18 arcs/10 cm and then finally cut and that the cut filling fibre has a Blowbox height ratio of between 4 and 15, preferably between 6 and 14 and that the finishing agent is an amino-functional finishing agent.
7. Process according to claim 6 whereby the finishing agent is a silicone oil.
8. Process according to claim 6, whereby the fibre is equipped with a finishing agent layer of 0.3 to 3.0 % weight percent, in relation to the total mass of the finished fibre.
9. Process according to claim 6 whereby the fibres are spun in a dry-wet spinning process.
10. Use of a cellulosic filling fibre with an individual fibre titre of 0.7 to 6.0 dtex which reveals a crimping produced in a crimping device with a number of arcs of at least 18 arcs/10 cm and a finishing agent layer of an amino-functional finishing agent and a Blowbox height ratio of between 4 and 15, preferably between 6 and 14, as a filling material for bed wear and clothing.
11. Use of a cellulosic filling fibre according to claim 10 in a blend with down and/or feathers.
12. Use of a cellulosic filling fibre according to claim 10 in a blend with fibres of polyester, polylactic acid, polypropylene, capok and/or poplar fluff.

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