DE102015010966A1 - cleaning cloth - Google Patents

Abstract

A cleaning fabric, in particular a cleaning cloth, comprising a microfiber composite sheet comprising - at least a first layer A containing a fibrous component in the form of a non-woven microfiber having an average titer of less than 1 dtex, more preferably less than 0.1 dtex, more preferably from 0.03 dtex to 0.06 dtex, in particular in the form of melt-spun and nonwoven microfilaments, and / or composite filaments which are at least partially composed of elementary filaments having an average titer of less than 1 dtex, preferably less than 0, 1 dtex, more preferably from 0.03 dtex to 0.06 dtex are split and solidified, - at least one layer B is disposed on the first layer A, wherein the layer B has an open-pore pore structure with an average pore size of 1 to 1000 microns , - If necessary, at least one second layer A is disposed on the layer B, wherein the microfibers, microfilaments and / or elemental filaments de The first and / or second layer A penetrate at least partially into the pores of the layer B and are intertwined with the filaments of the respective other layer A and / or in the pores of the layer B.

Description

Technical area

Textile physical properties of cleaning wipes can be controlled via the chemical and textile-physical properties of the fibers or filaments forming them. The fiber or filament raw materials are selected according to the desired chemical or physical properties, for example with regard to their colorability, chemical resistance, their thermoformability, their Schmutzaufnahme- or their adsorption capacity. The modulus and force-strain properties of the fibers or filaments are u. a. Depending on the material properties, which can be controlled by the choice of the degree of crystallization and / or orientation and the cross-sectional geometry in order to influence the bending stiffness, the force absorption or the specific surfaces of the individual fibers or filaments. The sum of the textile-physical properties of the fibers or filaments forming a textile fabric is also controlled by the weight per unit area.

For many applications, cleaning wipes must meet a variety of requirements, which are often difficult to reconcile. For example, microfiber nonwovens should both have a long service life and good handleability, especially when soaking, wringing and wiping, good cleaning efficiency, good resistance to mechanical wear and / or a specific water balance.

State of the art

One way to combine different properties in a cleaning fabric is to combine different types of fibers with one another when selecting the type of production of the fabric (for example, as a woven or knitted fabric or as a nonwoven fabric). Thus, fabrics, knits or knitted fabrics which contain thicker fibers in combination with microfibers show a good durability and at least initially satisfactory performance properties. A disadvantage of these fabrics, however, is that they are more expensive to produce than nonwovens. In addition, knits in particular have insufficient retention capacity for microfibers. Thus it was found that after about 400 industrial washing cycles (according to DIN EN ISO 155797 ) the microfiber portions are almost completely removed. This is reflected in a significant deterioration in the performance characteristics, such as manageability, skin sensor, cleaning efficiency or water balance.

Nonwovens containing microfibers are significantly easier to manufacture compared to woven, knitted or knitted fabrics. Nonwovens are structures of limited length fibers (staple fibers), filaments (continuous fibers) or cut yarns of any kind and of any origin which have been somehow joined together to form a nonwoven (fibrous web) and interconnected in some way. Microfibre nonwovens basically have excellent properties in the removal of dirt and in the uptake and release of liquids, especially water. However, it is disadvantageous in the known microfiber nonwovens that their durability, in particular in the case of frequent washing in industrial washing cycles, is limited, which is reflected, for example, in the formation of holes in the nonwovens occurring after about 200 industrial washing cycles. For professional cleaning applications, these 200 wash cycles mean, for example, daily sanitizing laundry will last less than a year.

By increasing the proportion of thicker fibers, the durability of the nonwoven fabrics can theoretically be improved as the chemical and mechanical stability of the individual fibers or filaments increases with their thickness. However, this comes at the expense of the use characteristics.

An increase in the proportion of thin fibers is expected to result in an improvement in performance, including improved water pick-up by creating a higher number of capillary gaps and a softer feel due to the reduced flexural stiffness of the single fiber. Such fabrics, however, prove to be fragile when comparing tear strength, pilling and above all washability, in particular Kochwaschbarkeit, with conventional textiles. In particular, the properties attributable to the microfibers deteriorate significantly over time.

Thus, for a PIE 16 nonwoven fabric (70% PET 0.2 dtex, 30% PA6 0.1 dtex, split and hydroentangled), a stress test of 400 wash cycles was performed DIN EN ISO 155797 found that the basis weight had decreased significantly. A more detailed analysis showed that the polyamide content of originally dropped to as much as 10% by weight while the proportion of PET decreased less. This result was surprising in that PET is known to be attacked by bases such as wash liquors, but polyamide is not. The result is explained by the fact that the finer polyamide filaments in the microfilament nonwoven fabric are more subject to the chemical and mechanical stress in the laundry, as well as the high mechanical friction during drying in drums and are transported away over the course of time as fiber breakage. This could also be due to the lower fiber thickness compared to polyester.

The reduction in the proportion of PA6 after every 500 washes is illustrated in the following table. The polyamide residual content was determined by dissolution with formic acid. The individual samples show the scattering of the PA6 decrease. Table 1: Lowering of PA6 content after 500 washes (60 ° C) from originally 30% to: N ° Gross corr; -0.073 Weighed PET corr; -0.071 gives PA6 Salary PA6 ^G G G G 9 % 1 1.475 1,402 1.26 1,189 0.213 15.19 2 0.673 0.6 0.593 0.522 0.078 13,00 3 0.97 0.897 0.855 0.784 0.113 12.60 4 1,567 1,494 1.36 1,289 0,205 13.72 5 1,605 1,532 1,442 1,371 0.161 10.51 6 1,301 1,228 1,173 1,102 0.126 10.26

Another way to unite truly contradictory properties with each other in one sheet is to make composites of two or more sheets. For this purpose, the individual sheets can be produced separately and then joined together by known joining methods, such as sewing, gluing, laminating.

Also known are multi-component spunbonded fabrics which have a titer gradient. That's how it describes EP 1 619 283 A1 Multi-component spunbonded nonwovens consisting of at least two polymers forming interfaces with one another, which originate from at least one spinning device with uniform spinneret openings and which are hydrodynamically stretched, laid down in a planar manner and solidified together either as individual layers or as a multi-component composite.

The invention here has the object of developing the known microfiber nonwovens to the effect that they have good mechanical properties, in particular a good Dauerwaschbeständigkeit with good performance characteristics, a good thermophysiological comfort, pleasant skin sensor and optics, good water management (absorption and water release, preferably evenly) and a offer good cleaning efficiency.

Presentation of the invention

• – mindestens eine erste Lage A aufweist, die eine Faserkomponente in Form zu einem Vlies abgelegter Mikrofasern mit einem mittleren Titer von weniger als 1 dtex, vorzugsweise weniger als 0,1 dtex, noch bevorzugter von 0,03 dtex bis 0,06 dtex, insbesondere in Form schmelzgesponnener und zu einem Vlies abgelegter Mikrofilamente umfasst und/oder Verbundfilamente, die zumindest teilweise zu Elementar-Filamenten mit einem mittleren Titer von weniger als 1 dtex, vorzugsweise weniger als 0,1 dtex, noch bevorzugter von 0,03 dtex bis 0,06 dtex gesplittet und verfestigt sind,
• – mindestens eine Lage B auf der ersten Lage A angeordnet ist, wobei die Lage B eine offenporige Porenstruktur mit einer mittleren Porengröße von 1 bis 1000 μm, bevorzugt von 10 bis 100 μm, insbesondere von 25 bis 50 μm aufweist,
• – gegebenenfalls mindestens eine zweite Lage A auf der Lage B angeordnet ist,

The invention relates to a cleaning fabric, in particular a cleaning cloth, comprising a microfiber composite sheet, the

• At least one first layer A having a fiber component in the form of a nonwoven deposited microfibers having a mean titre of less than 1 dtex, preferably less than 0.1 dtex, more preferably from 0.03 dtex to 0.06 dtex, in particular in the form of melt-spun and nonwoven microfilaments and / or composite filaments at least partially constituted by elemental filaments having an average titer of less than 1 dtex, preferably less than 0.1 dtex, more preferably from 0.03 dtex to 0, 06 dtex are split and solidified,
• - At least one layer B is disposed on the first layer A, wherein the layer B has an open-pored pore structure having an average pore size of 1 to 1000 .mu.m, preferably from 10 to 100 .mu.m, in particular from 25 to 50 microns,
• If appropriate, at least one second layer A is arranged on the layer B,

wherein the microfibers, microfilaments and / or elementary filaments of the first and / or second layer A at least partially penetrate into the pores of the layer B, preferably the pores of the layer B at least penetrate proportionately, and are intertwined with the microfibers, microfilaments and / or elemental filaments of the other layer A and / or in the pores of the layer B.

The invention further relates to a process for the preparation of such a cleaning fabric and the use of the products obtained therefrom.

The cleaning fabric according to the invention is characterized in one embodiment in that it has at least two outer layers A with fine microfibers, microfilaments and / or elementary filaments and at least one layer B arranged between these two layers with an open-pored pore structure, wherein the microfibers of the ( with respect to the middle layer B) outer layers A at least partially penetrate into the pores of the layer B, preferably at least partially penetrate the pores of the layer B, and are intertwined with the microfibers of the other outer layer A. By virtue of this arrangement, the microfibers of the first and / or second layer A are present at least partially in the respective other outer layer A. In this case, a particularly good penetration of the middle layer B can be achieved if it has a comparatively small thickness of preferably less than 1 mm, in particular from 0.1 to 1 mm, measured according to EN 29073 - T2 , having. In order that the microfibers of the outer layers A (with respect to the middle layer B) can at least partially penetrate the pores of the middle layer B, at least some pores must pass over the layer thickness z. Advantageously, the layer B thus has an open-pore pore structure with an average pore size of the through-pores of 1 to 1000 pores / mm ² , preferably 10-100 pores / mm ² . In this case, z. B. in a layer arrangement ABA an entanglement of the fibers from the layer A with the fibers of the opposite (and separated by the layer B) layer A and optionally additionally carried out in the pores of the layer B.

In another embodiment of the invention, the cleaning fabric according to the invention is characterized in that the microfibers, microfilaments and / or elementary filaments of the first and / or second layer A at least partially penetrate into the pores of the layer B and engulfed in the pores of the layer B. available. By virtue of this arrangement, the microfibers of the first and / or second layer A are at least partially present in the middle layer B. In this embodiment too, the microfibers of the outer layer (s) A (with respect to the middle layer B) can at least partially penetrate the pores of the middle layer B and be entangled with the microfibers of the respective other outer layer A.

In this embodiment, the thickness of the layers A and B can be adjusted as needed. Moreover, it is also advantageous in this embodiment, if through-pores in layer B be included. Advantageously, therefore, the layer B here also has an open-pore pore structure with an average pore size of the through-pores of 1 to 1000 pores / mm ² , preferably of 10-100 pores / mm ² .

According to the invention it has been found that a special cleaning textiles with excellent mechanical properties and good durability can be obtained by these special arrangements. Thus, the cleaning fabric according to the invention shows excellent durability washing resistance, especially in heavy-duty industrial hot washing cycles. In addition, the microfiber composite sheet offers satisfactory performance properties such as good thermophysiological comfort, pleasant skin feel and optics, good water management, and good cleaning efficiency.

This result was surprising in that although it was expected that the use of microfibers having a smaller fiber titer would lead to an improvement in performance characteristics, the resistance, and in particular, the durability of the microfiber composite sheet, would deteriorate.

Without wishing to be bound by any mechanism, it is believed that the good mechanical strength with respect to pilling, abrasion, and wash resistance of the microfiber composite sheet of the invention results from the high interfacial entanglement of the fine microfibers of sheet (s) A in the pores of sheet B, and / or is due to the fibers of the other outer layer A (so-called tentacle effect). This overlay fiber entanglement is facilitated by the open-pore pore structure of the inboard ply B and can be used in the manufacture of the microfiber composite sheet, i. H. during splitting or during the solidification process, for example during needling and / or hydroentanglement of the composite elements are achieved.

According to the invention, the microfibers, microfilaments and / or elementary filaments of the first and / or second layer A are at least partially overlapping the layer B with the microfibers, microfilaments and / or elementary filaments of the respective other layer A and / or in the pores of the layer B devoured (" Tentacle effect "). This effect can be achieved, for example, by first forming a layer composite AB or even larger layer composites, for example a layer composite ABA, ABABA etc., from initially unconsolidated or merely preconsolidated layers A and layer (s) B, and then a splitting or Solidification step for the entire layer composite is performed.

In this procedure, the microfibers, microfilaments, and / or the fine elemental filaments obtained by splitting the first and / or second layer A in the Z direction, i. H. in the direction of the cross section of the microfiber composite sheet. This distribution can comprise several layers and leads to a particularly intensive connection of the individual layers. Practical experiments have shown that the finer the microfibers, microfilaments and / or elemental filaments are transported into the other layers.

Especially with a thicker middle layer B, for example 3 or more times as thick as layer A, measured according to EN 29073 - T2 , It is manufacturing technology advantageous if the composite layer is constructed as ABA. In this case, in particular, the inner core, constructed by the layer B, have special properties such as high water absorption or greater rigidity against bending than the layer (s) A. Advantageously, the layer B can be produced from a cost-effective material and inexpensive production methods As a result, a comparatively thick cleaning fabric can be produced at low cost, which corresponds to many relevant application requirements, such as good hand-pickability, more uniform contact pressure when cleaning surfaces by hand or wringing a floor wiping cloth in a simple funnel press. The layer A, however, can be made very thin in this embodiment, for example, with a basis weight of 5 to 60 g / m ² , preferably 10 to 40 g / m ² . This has the advantage that special, possibly more expensive, materials can be used for the dissolving and picking up of dirt and for the delivery of water to the surface to be cleaned, for example submicron fibers.

According to the invention, the fiber component of the first and / or second layer A comprises microfibers, preferably melt-spun and microfilaments deposited in a nonwoven, in particular at least partially split composite filaments. The term filaments according to the invention are understood to mean fibers which, unlike staple fibers, have a theoretically unlimited length. Composite filaments consist of at least two elementary filaments and can be split and solidified into elementary filaments by conventional grit methods such as water jet needling. The composite filaments of the first and / or second layer A according to the invention are at least partially split into elementary filaments. The degree of chipping is advantageously more than 80%, more preferably more than 90% and in particular 100%.

In order to achieve a sufficient stabilizing effect, it is advantageous if the proportion of the microfibers, microfilaments and / or elementary filaments of the first and / or second layer A, based on the total weight of the microfiber composite sheet and as a cumulative value over all composite layers away at least 5 wt. %, is. Practical experiments have shown that a particularly high washing strength can be produced in combination with good performance properties, when the proportion of these microfibers of 5 wt.% To 60 wt.%, In particular from 5 wt.% To 25 wt.%, Based on the Total weight of the microfiber composite sheet is.

With regard to the individual layers of the microfiber composite sheet, it is advantageous if the proportion of the microfibers, microfilaments and / or elementary filaments of the first and / or second layer A in the respective layer A, for example in an outer layer A or in an interior lying layer A of 80 wt.% To 100 wt.%, Preferably from 90 wt.% To 100 wt.%, In particular 100 wt.%, Each based on the total weight of the layer A.

With regard to the continuous use properties (pilling, abrasion and washing resistance), it is advantageous if at least one outer layer advantageously but both outer layers of the microfiber composite sheet of the layers A are formed.

In principle, it is conceivable that the respective layers A contain, in addition to the fiber component of the first and / or second layer A, further fibers. However, particularly good service properties are obtained if at least the outer layers A consist entirely of microfibers, microfilaments and / or elementary filaments of the first and / or second layer A.

An advantage of the use of composite filaments as starting material for producing the elemental filaments is that the titer of the elementary filaments produced from them can be adjusted in a simple manner by varying the number of elementary filaments contained in the composite filaments. In this case, the titer of the composite filaments can remain constant, which is advantageous in terms of process technology. Another advantage of using the composite filaments is that in addition, by varying the degree of splitting of the composite filaments, the ratio of thicker and thinner filaments in the microfiber composite sheet can be more easily controlled.

Practical experiments have shown that microfiber composite sheets having a particularly high washing strength combined with good performance can be obtained when the average denier of the microfibers, microfilaments and / or elementary filaments of the first and / or second layers A is from 0.01 to 1 dtex , preferably from 0.01 to 0.1 dtex, in particular from 0.03 dtex to 0.06 dtex. For example, elementary filaments having this denier can be obtained by splitting composite filaments having a titer of from 1 to 6.4 dtex, preferably from 1.2 to 3.8 dtex.

The elementary filaments can be formed in cross-section circular segment-shaped, n-sided, or multilobal.

Preferably, the microfiber composite sheet of the present invention is one in which the composite filaments have a cross-section of orange-slit-like or "pie" -type multisegment structure, which segments may contain different, alternating, incompatible polymers. Also suitable are hollow-pie structures that can also have an asymmetrically axially extending cavity. Pie structures, in particular hollow-pie structures, can be split particularly easily.

With regard to the fiber component of the first and / or second layer A, the orange-slit or pie-piece arrangement (pie arrangement) advantageously has 2, 4, 8, 16, 24, 32 or 64 segments, particularly preferably 16, 24 or 32 Segments, up.

In order to obtain easy splittability, it is advantageous if the composite filaments comprise filaments which contain at least two thermoplastic polymers. Preferably, the composite filaments comprise at least two incompatible polymers. Incompatible polymers are to be understood as meaning those polymers which in combination do not give only limited or poorly adhering pairings. Such a composite filament has a good cleavability in elementary filaments and causes a favorable ratio of strength to basis weight. Only conditionally or poorly adhering pairings are present if the splitting of the composite filaments having these pairings is simpler than with a composite filament which consists only of one of the polymers used.

As incompatible polymer pairs, polyolefins, polyesters, polyamides and / or polyurethanes are preferably used in such a combination that does not result in only limited or difficultly adhesive pairings.

The polymer pairs used are particularly preferably selected from polymer pairs with at least one polyolefin and / or at least one polyamide, preferably with polyethylene, such as polypropylene / polyethylene, polyamide 6 / polyethylene or polyethylene terephthalate / polyethylene, or with polypropylene, such as polypropylene / polyethylene, polyamido / polypropylene or polyethylene terephthalate / polypropylene.

Very particular preference is given to polymer pairs with at least one polyester and / or at least one polyamide.

Polymer pairs with at least one polyamide or with at least one polyethylene terephthalate are preferred because of their conditional bondability, and polymer pairs with at least one polyolefin are particularly preferably used because of their poor bondability.

Polyesters, preferably polyethylene terephthalate, polylactic acid and / or polybutylene terephthalate on the one hand, polyamide, preferably polyamide 6, polyamide 66, polyamide 46 on the other hand, if appropriate in combination with one or more further polymers which are incompatible with the abovementioned components, have been preferably selected as particularly preferred components made of polyolefins proved to be particularly useful. This combination has excellent cleavability. The combination of polyethylene terephthalate and polyamide 6 or of polyethylene terephthalate and polyamide 66 is very particularly preferred.

The basis weight of a single ply A may vary depending on the materials used and the desired properties of the microfiber composite sheet. In general, basis weights in the range of 5 g / m ² to 150 g / m ^2, preferably from 10 g / m ² to 100 g / m ² , more preferably from 10 g / m ² to 50 g / m ² , as proved favorable.

According to the invention, the layer B has an open-pored pore structure with an average pore size of from 1 to 1000 μm, preferably from 10 to 100 μm, in particular from 25 to 50 μm. To determine the pore diameter, the test device "Topas, Pore Size Meter for Filter Papers, Woven Materials, Non-Woven and other Porous Materials PSM 165" can be used. The measuring method used there is in accordance with the Standard ASTM E 1294-89 and ASTM F316-03 ,

In a preferred embodiment of the invention, the layer B has an average pore density of from 1 to 1000 pores / mm ² , preferably from 10 to 100 pores / mm ² , more preferably from 20 to 40 pores / mm ² .

In practical experiments it has been found that with these average pore diameters and pore densities a particularly good penetration or entanglement of the layer B with the fine filaments of the layer A can be achieved.

Another advantage of the comparatively high pore diameters and pore densities is that the layer B thereby has a good water absorption capacity, which has a positive effect on the cleaning performance of the microfiber composite sheet. In addition, a particularly uniform penetration of the layer B by the fine fibers of the layer A and thus a very homogeneous Tentakeleffekt can be achieved.

In a further advantageous embodiment of the invention, the layer B has an air permeability, measured according to DIN EN ISO 9237 , from 200 to 1500, preferably from 400 to 1300, more preferably from 600 to 1300 l / m ² s, at 100 Pa. An advantage of these comparatively high air permeabilities is that the hydrodynamic solidification of the layer composite, the water well through the composite surface and thereby good intangibles of the fibers can be achieved.

The basis weight of the layer B may vary depending on the materials used and the desired properties of the microfiber composite sheet. In general, basis weights in the range of 5 to 300 g / m ² , preferably from 10 to 200 g / m ² , more preferably from 50 to 150 g / m ^{2 have} proven to be favorable.

The materials that make up layer B can vary widely. Thus, fiber materials and non-fiber materials can be used.

In a preferred embodiment of the invention, the layer B does not comprise a fiber component in the form of non-woven and consolidated fibers having an average titer of 0.1 to 3 dtex.

In practical experiments, it has proved to be advantageous if the layer B contains and / or consists of one or more of the following products: open-pore foams, perforated films, net-like fabrics, nonwovens, woven fabrics, knitted fabrics, knitted fabrics, knitted spacer fabrics. These products can be made of a variety of materials. Due to their good water absorption capacity, foams or films based on PVA or cellulose have proven to be particularly suitable. However, foams or films of polyurethane, polyether, polystyrene, polyester, melamine resin, viscose, polypropylene, EPDM (ethylene-propylene-diene rubber), collagen are also suitable.

As already explained above, an essential characteristic of the microfiber composite sheet according to the invention is the alternating arrangement of layers of fibers with small fiber titers and layers with an open-pored pore structure. Particularly advantageous is the arrangement according to the invention, in which the open-pored pore structure of the layer B of fibers from the fiber layers with a low titer are at least partially penetrated ("tentacle effect"). In this way, a maximum protection of the inner layers of fine filaments lying on the outside can be achieved, since these provide a good integration of the layer B combined with a high stability, both with itself and across layers, due to their high degree of entanglement. At the same time, the outer fine filaments, which due to the lower mechanical strength and rigidity per se have a higher pilling tendency (fibers can be easily released from the composite by mechanical stress), are better anchored in the overall composite of the nonwoven fabric. This can be done in particular by the above-mentioned "tentacle effect".

Against this background, it is advantageous if at least part of the surface of the microfiber composite sheet is formed by the microfibers, microfilaments, and / or elementary filaments with a titre of less than 1 dtex. Accordingly, at least one, preferably both, of the surfaces of the microfiber composite sheet is advantageously formed of at least 50%, preferably 60 to 100% of the microfibers, microfilaments, and / or elementary filaments having a denier of less than 1 dtex. The structure and composition of the surface can be determined, for example, by means of SEM images.

The provision of the fine microfibers on the outside of the microfiber composite sheet has the advantage that internal open-pored layers B of any kind can be mechanically stabilized. At the same time, the surface of the microfiber composite sheet is characterized by advantageous performance properties as well as a favorable aspect and feel.

The formation of the alternating arrangement of at least one open-pored layer B and at least one layer A with fine fibers in the microfiber composite sheet according to the invention can take place, for example, by producing the layers A and B separately and joining them together in the desired arrangement. The bonding of the layers can be effected by known joining methods, mechanical needling and / or hydroentanglement, wherein the penetration of the pores of the layer B with the fibers of the first and / or second layer A, and optionally the cross-layer entanglement of the fibers of the layer A with the Fibers of the other layer A takes place and the individual layers are optionally also solidified. The connection of the layers is particularly simple in the context of a hydroentanglement of the composite filaments. The layers can also be pre-consolidated separately before the connection.

In order to obtain a high degree of entanglement, it is expedient if the degree of splitting of the first and / or second layer A is as high as possible. Against this background, the proportion of the respective elementary filaments in the layers A is advantageously more than 80% by weight, more preferably 85 to 100% by weight.

In a particularly preferred embodiment of the invention, all layers A contain at least partially split Pie 8, Pie 12, Pie 16, Pie 24 filaments, Pie 32 filaments and / or Pie 64 filaments.

As already explained above, it has proved to be particularly favorable to arrange the layers such that the at least one layer B is located in the interior of the microfiber composite sheet while the layers A are arranged at least on the surfaces of the microfiber composite sheet. In this arrangement, the outer layers of fine filaments can surprisingly effectively protect the inner layers, despite their fine deniers and their resulting mechanical sensitivity, which, as explained above, leads to the formation of a particularly stable composite layer and good long-term use properties.

This effect may possibly be due to the fact that the microfibers, for example the fine filaments obtained during the splitting, in the Z-direction solidification step, i. H. in the direction of the cross section of the microfiber composite sheet. This distribution can comprise several layers and leads to a particularly intensive connection of the individual layers. Practical experiments have shown that the elementary filaments are transported further into the adjacent layers, the finer they are.

The microfiber composite sheet according to the invention contains at least one layer A and at least one layer B. According to the invention, at least one second layer A is preferably arranged on the layer B. As a result, the alternating base layer sequence A-B-A is obtained. In principle, different layers A (and also B) may be the same or different in composition, structure, thickness and other parameters, for example. As explained above, by incorporating the layer B into the interior of the laminate, a microfiber composite sheet having excellent durability can be obtained. Further, by forming the outsides of the microfiber composite sheet through the layers A, the microfiber composite sheet exhibits very good performance properties.

The base layer sequence ABA according to the invention can be extended by further alternating layers A and B. A further preferred embodiment of the invention thus comprises the layer sequences: A (BA) _n BA, where n = 0 to 20, preferably from n = 1 to 15, more preferably from n = 5 to 15 and in particular from n = 8 to 12. Examples of layer sequences are thus ABABABA, ABABABABA etc. It is conceivable that one of the outer layers A is replaced by a layer X which is not a microfiber layer.

It is also conceivable for one or more layers A to comprise a plurality of sub-layers A 'and / or one or more layers B multiple sub-layers B'. The titer of the fibers in the respective documents may be the same or different from each other. In a spinning system with 15 spinning positions, for example, the following arrangement of the sub-layers A 'and B' would be conceivable: A'A'B'B'B'A'B'B'B'A'B'B'B'A ' A ', which gives the later viewer of the cross-section A (BA) ₂ BA.

According to a preferred embodiment of the invention, the outer layers are each formed by the layers A in the layer sequences. Furthermore, the layer sequences are advantageously characterized by an alternating arrangement of the layers A and B. However, as explained above, it is also conceivable that the layer sequence has further layers which are different from A and B.

It has also proven to be advantageous to design the layer sequence of the layers A and B, as well as any other layers present in the microfiber composite sheet, such that a symmetrical layer structure results. This arrangement has the advantage that a particularly uniform, side-symmetrical property profile can be obtained.

According to a preferred embodiment of the invention, all the layers A have fibers with the same fiber titer. These embodiments are advantageous because they allow a particularly easy production of the microfiber composite sheet. However, according to an alternative preferred embodiment, different layers A and / or sub-layers A '(and / or B') have fibers with different fiber titers. This is advantageous in that the properties of the microfiber composite sheet can be set very targeted and page-related.

The microfiber composite sheet of the invention may also contain other layers. It is conceivable that the further layers are designed as reinforcing layers, for example in the form of a scrim, and / or that they comprise reinforcing filaments, nonwoven composite fabrics, woven fabrics, knitted fabrics and / or scrims. Preferred materials for forming the further layers are plastics, for example polyesters, and / or metals. It is basically conceivable that the further layers form the outer layers of the microfiber composite sheet. Advantageously, however, the further layers (optionally additionally) are arranged in the interior of the microfiber composite sheet between the layers A and B.

The polymers used to make the filaments of the microfiber composite sheet may include at least one additive selected from the group consisting of color pigments, antistatic agents, antimicrobials such as copper, silver, gold, or hydrophilizing or hydrophobing additives in an amount of 150 ppm to 10 wt .%, contain. The use of said additives in the polymers used allows adaptation to customer-specific requirements.

The basis weights of the microfiber composite sheet of the invention are adjusted depending on the desired application. As for many applications have useful basis weights, measured according to DIN EN 29073 in the range from 15 to 500 g / m, preferably from 30 to 300 g / m ² , and especially from 50 to 250 g / m.

As explained above, the microfiber composite sheet of the invention is characterized by excellent mechanical properties. Thus, the microfiber composite sheet of the invention according to a preferred embodiment of the invention is characterized by a high durability. Thus, it has been found that exemplary microfiber composite sheets of the present invention continue to do so even after 850 industrial wash cycles DIN EN ISO 155797 have no holes.

Advantageously, the microfiber composite sheet is further characterized by an easily adjustable tear propagation force according to DIN EN ISO 155797 , Furthermore, the microfiber composite sheet according to the invention is characterized by a well-adjustable moisture balance.

• – Es wird mindestens eine Faserlage A, die zu einem Vlies abgelegte Mikrofasern mit einem mittleren Titer von weniger als 1 dtex, vorzugsweise weniger als 0,1 dtex, noch bevorzugter von 0,03 dtex bis 0,06 dtex, insbesondere in Form schmelzgesponnener und zu einem Vlies abgelegter Mikrofilamente und/oder Verbundfilamente umfasst, bereitgestellt und/oder es wird mindestens eine Faserlage A, die eine Faserkomponente in Form schmelzgesponnener und zu einem Vlies abgelegter Verbundfilamente umfasst, ersponnen, zu einem Vlies abgelegt und gegebenenfalls, beispielsweise durch Vernadelung, vorverfestigt;
• – es wird mindestens eine Lage B, die eine offenporige Porenstruktur mit einer mittleren Porengröße von 1 bis 1000 μm bevorzugt von 10 bis 100 μm, insbesondere von bis 25 bis 50 μm aufweist, bereitgestellt;
• – die Faserlagen A und B, werden alternierend aufeinander angeordnet, wobei vorzugsweise mindestens eine äußere Lage durch die Faserlage A gebildet wird;
• – der Lagenverbund wird anschließend einer mechanischen Verfestigung, insbesondere einer Hydrofluidbehandlung, unterzogen, wobei gegebenenfalls eine Splittung der Faserkomponente der Faserlagen A stattfindet, welche zumindest teilweise zu Elementar-Filamenten mit einem mittleren Titer von weniger als 1 dtex, vorzugsweise weniger als 0,1 dtex, noch bevorzugter von 0,03 dtex bis 0,06 dtex gesplittet und verfestigt werden und wobei die Mikrofasern, Mikrofilamente und/oder Elementar-Filamente der ersten und/oder zweiten Lage A die Poren der Lage B zumindest anteilig durchdringen und sich mit den Mikrofasern, Mikrofilamenten und/oder Elementar-Filamenten der jeweils anderen Lage A und/oder in den Poren der Lage B verschlingen;
• – Konfektionierung des Lagenverbunds unter Ausbildung des Reinigungstextils.

The microfiber composite sheet according to the invention can be produced in a manner known to the person skilled in the art, for example as follows:

• It is at least one fiber layer A, the microfibers deposited into a nonwoven with an average titer of less than 1 dtex, preferably less than 0.1 dtex, more preferably from 0.03 dtex to 0.06 dtex, in particular in the form of melt spun and at least one fiber layer A comprising a fiber component in the form of melt-spun and nonwoven composite filaments spun, laid down to a nonwoven and optionally pre-consolidated, for example by needle punching ;
• - It is at least one layer B, which has an open-pored pore structure with an average pore size of 1 to 1000 microns, preferably from 10 to 100 .mu.m, in particular from to 25 to 50 microns provided;
• - The fiber layers A and B are arranged alternately to each other, preferably at least one outer layer is formed by the fiber layer A;
• - The layer composite is then subjected to mechanical solidification, in particular a hydrofluidic treatment, optionally taking place a splitting of the fiber component of the fiber layers A, which at least partially to elemental filaments having a mean titre of less than 1 dtex, preferably less than 0.1 dtex more preferably from 0.03 dtex to 0.06 dtex are split and solidified and wherein the microfibers, microfilaments and / or elementary filaments of the first and / or second layer A at least partially penetrate the pores of the layer B and intermesh with the microfibers , Microfilaments and / or elementary filaments of the other layer A and / or in the pores of the layer B devour;
• - Assembly of the layer composite with formation of the cleaning fabric.

A process has proven to be particularly simple in which at least one first fiber layer comprising filaments of the first and / or second layer A and at least one layer B are produced separately and joined together.

Advantageously, the process for producing the microfiber composite sheet according to the invention is carried out as follows:
First, the individual fiber layers A are spun separately, stored to a nonwoven and optionally pre-consolidated, for example by needling. Subsequently, the fiber layers A and the open-pore (s) layer (s) B are connected to each other. It is also conceivable to spin up the individual fiber layers A directly onto the layer B.

The connection of the individual layers can then be effected by known joining methods, for example by means of mechanical consolidation, such as needling and / or hydrofluidic treatment. In this case, the individual layers can be both solidified and simultaneously connected to one another.

By hydrofluidic treatment, the microfiber composite sheet may optionally be split, as well as solidified over layers, and intimately intertwined or continuously felted. This approach allows for a particularly effective use of the low filament denier fibers since the fine fibers are transported very deep into the microfiber composite sheet and obviously cause their entanglement to result in particularly effective stabilization of the composite "tentacle effect".

The solidification and optionally splitting of the composite filaments advantageously takes place in that the optionally preconsolidated nonwoven composite is subjected at least once on each side to high-pressure fluid jets, preferably high-pressure jets of water. The microfiber composite sheet according to the invention can thereby obtain the appearance of a textile surface and the degree of splitting of the composite filaments can be set to more than 80%.

As discussed above, to facilitate separation into the elementary filaments, the composite filaments may have a central opening, particularly in the form of a tubular elongated cavity, which may be centered with respect to the central axis of the composite filaments. By this arrangement, the close contact between the elementary filaments, which are formed by the inner angle of the gaps or circular cutouts, before separation of the elementary filaments, as well as the contact in this range of different elementary filaments made of the same polymer material, reduce or avoid.

To further consolidate the microfiber composite sheet structure, the composite filaments may have a latent or spontaneous crimp resulting from an asymmetric configuration of the elementary filaments with respect to their longitudinal centerline, which crimping may be achieved by a crimping process asymmetric, geometric configuration of the cross section of the composite filaments is activated or amplified. As a result, the microfiber composite sheet can be provided with a high thickness, a low modulus and / or a multi-axial elasticity.

In one variant, the composite filaments may have a latent or spontaneous curl due to a differentiation of the physical properties of the polymer filaments forming the elementary filaments in the spinning, cooling and / or stretching operations involving the composite filaments, resulting in distortions caused by internal stresses asymmetric loads are caused with respect to the longitudinal central axis of the composite filaments, wherein the crimping is optionally activated or reinforced by an asymmetric, geometric configuration of the cross section of the composite filaments.

The composite filaments may have a latent crimp which is activated by thermal, mechanical or chemical treatment prior to formation of the microfilament composite sheet.

The crimp can be thermally or chemically reinforced by additional treatment prior to solidification of the microfiber composite sheet, for example. The solidification of the nonwoven according to the invention preferably takes place by treatment with high-pressure fluid jets. Thus, during or after the division of the composite filaments, the elementary filaments can be strongly entangled with a mechanical means (needling, liquid pressure jets) acting predominantly perpendicular to the material plane.

The filaments, in particular the composite filaments, can be deposited, for example by mechanical and / or pneumatic deflection, wherein at least two of these types of deflection can be combined, as well as by spinning on an endless treadmill and mechanically by needling or by the action of liquid pressure jets can be acted upon with solid (micro) particles. The steps of entanglement and separation of the composite filaments into elementary filaments can be carried out in one and the same process step and with one and the same device, wherein the more or less complete separation of the elementary filaments can end with an additional, more directed to the separation, process.

The strength and mechanical resistance of the microfiber composite sheet can also be significantly increased if it is provided that the elementary filaments are bonded to each other by a thermal fusion involving one or more of them, preferably by hot calendering with heated, smooth or engraved rolls Pulling through a hot-air tunnel kiln, by pulling on a through-flow of hot air drum and / or by applying a binder contained in a dispersion or in a solution or powdered.

In one variant, solidification of the nonwoven fabric may also be effected, for example, by hot calendering prior to any separation of the unitary composite filaments into elementary filaments, the separation occurring after nonwoven bonding.

Furthermore, the nonwoven fabric can also by a chemical treatment (as for example in the French Patent No. 2,546,536 the Applicant is described) or solidified by a thermal treatment, which leads to a controlled shrinkage, at least a portion of the elementary filaments, after their optionally carried out separation. This results in a shrinkage of the fabric in the width and / or longitudinal direction.

Further, the microfiber composite sheet may be subjected to chemical type solidification after bonding or finishing such as anti-pilling treatment, hydrophilization or hydrophobization, antistatic treatment, refractory improving treatment and / or tactile property modification or gloss, a mechanical treatment such as roughening, sanforizing, emery or tumbler treatment and / or a change appearance treatment such as dyeing or printing.

Practical experiments have shown that a microfiber composite sheet having a particularly homogeneous structure can be obtained when the nonwoven fabric is treated by exposure to temperature and / or pressure, preferably by calendering at a temperature of 160 to 220 ° C, preferably 180-200 ° C and / or a line pressure of 20 to 80 N / mm is pre-consolidated.

Advantageously, the microfiber composite sheet according to the invention is subjected to a point calendering to increase its abrasion resistance. For this purpose, the split and solidified microfiber composite sheet is passed through heated rollers, of which at least one roller has elevations, which lead to a selective fusion of the filaments with each other. According to a preferred embodiment of the invention, the composite filaments are dyed by spin dyeing.

It is also conceivable that the microfiber composite sheet according to the invention is finished by a coating or lamination process. However, at least one of the outer layers A remains because of its good water absorption capacity (absorbency) in combination with its excellent washability, the cleaning fabric of the invention is ideal for the cleaning of various surfaces. Particularly good results are achieved when cleaning smooth surfaces.

Brief description of the figures

In the figure shows:

1 A schematic cross-sectional view of a cleaning fabric of the invention comprising a microfiber composite sheet comprising a layer A comprising a fiber component in the form of composite filaments partially split into elementary filaments and solidified, a layer B disposed on the first layer A. wherein the layer B has an open-pore pore structure with an average pore size of more than 500 microns and wherein the elementary filaments of the first layer A, the pores of the layer B proportionately penetrate and are entwined in the pores of the layer B.

2 A schematic cross-sectional view of a cleaning fabric according to the invention comprising a microfiber composite sheet having two outer layers A, each comprising a fiber component in the form of composite filaments partially split into elementary filaments and solidified, a layer B between the two layers A, wherein the layer B has an open-pored pore structure with an average pore size of more than 500 microns and wherein the elementary filaments of the two layers A, the pores of the layer B proportionately penetrate and are entwined with the elementary filaments of the middle layer B. ,

3 and 4 SEM images of the cross section of a cleaning fabric according to the invention.

5 SEM image of a top view of a cleaning fabric according to the invention.

Embodiment of the invention

1 shows a schematic view of the cross section of a cleaning fabric according to the invention, comprising a microfiber composite sheet 1 , This has a layer A 2, which comprises a fiber component in the form of melt-spun and laid-to-a nonwoven composite filaments, at least partially to elementary filaments 3 with a mean titer of less than 1 dtex, are split and solidified. On the layer A 2, a layer B 4 is arranged, wherein the layer B 4 has an open-pored pore structure with an average pore size of more than 500 microns and wherein the elemental filaments 3 able A 2, the pores of the layer B 4 proportionately penetrate and in the pores 5 the situation B 4 are devoured.

2 shows a schematic view of the cross section of a cleaning fabric according to the invention, comprising a microfiber composite sheet 1 , This has two outer layers A 2, each comprising a fiber component in the form of composite filaments, which are partially split into elementary filaments and solidified, a layer B 4 is disposed between the layers A 2, wherein the layer B is an open-pore Having pore structure with a mean pore size of more than 500 microns and wherein the elementary filaments of the two layer A 2, the pores 5 penetrate the position B 4 proportionally and with the elementary filaments 3 the middle layer B are devoured.

3 and 4 each show SEM images of the cross section of a cleaning fabric according to the invention.

5 shows an SEM image of the top view of a cleaning fabric according to the invention. It can be seen that elementary filaments of the outer layer A partially penetrate the pores of the layer B and are entangled in the pores of the layer B.

In the following the invention will be explained in more detail with reference to several examples.

example 1

In a first embodiment, a layer composite ABA is produced. Filament nonwoven layers with an average thickness of 0.02 mm to 0.03 mm are deposited via 16 spinnerets connected in series. First, 8 thin layers are deposited continuously on a belt over the first 8 nozzles. The thin nonwovens are thereby produced by composite filaments which consist of 32 elementary filaments and have a titer before splits of 1.6 dtex and a polymer ratio of PET to PA6 of 70/30. After dropping off The first 8 thin layers and before depositing the next 8 identical thin layers, a web of the layer B is continuously fed, preferably in the width of the deposited thin nonwovens. The layer B here consists of a viscose fiber nonwoven (145 g / m ² ), only slightly pre-needled on two sides. The underside of layer B is thus deposited on the first 8 thin layers.

Subsequently, the thin layers 9, 10, ... to 16 are placed on the top of the layer B successively. This results in an unconsolidated composite layer ABA with unsplit composite filaments in the layers A.

In a next step, the entire composite layer is first driven through a needle chair and pre-consolidated with a few (about 20) stitches / cm ² and then driven through a water jet system, with the needling of all three layers and simultaneous splitting of the upper and lower water jet beams alternately Composite filaments in the layers A is made. In this step, the elementary filaments of the first and second layers A at least partially penetrate the pores of the layer B and engulf with the filaments of the respective other layer A and / or the pores of the layer B.

Example 2

In a second embodiment, the layer B is formed by a thin (eg 5 mm thick) foam structure. This open-pored foam structure is provided as rolled-up web material. In a first step, a thin layer A of unsplit composite filaments having a weight per unit area of 30 g / m ² is now applied to one side and loosely connected to the foam web by individual adhesive dots.

Subsequently, the two-ply composite is driven through a water-jet system in which the HE needling takes place on one side, and only from the side of the composite filaments of the layer A, which are split and devoured simultaneously in the pores of the open-pore foam structure.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 1619283 A1 [0010]
• FR 2546536 [0083]

Cited non-patent literature

• DIN EN ISO 155797 [0003]
• DIN EN ISO 155797 [0007]
• EN 29073 - T2 [0015]
• EN 29073 - T2 [0023]
• Standard ASTM E 1294-89 [0041]
• ASTM F316-03 [0041]
• DIN EN ISO 9237 [0045]
• DIN EN 29073 [0066]
• DIN EN ISO 155797 [0067]
• DIN EN ISO 155797 [0068]

Claims (14)

Cleaning fabric, in particular cleaning cloth, comprising a microfiber composite sheet, the At least one first layer A having a fiber component in the form of a nonwoven deposited microfibers having a mean titre of less than 1 dtex, preferably less than 0.1 dtex, more preferably from 0.03 dtex to 0.06 dtex, in particular in the form of melt-spun and nonwoven microfilaments, and / or composite filaments at least partially constituted by elemental filaments having an average titer of less than 1 dtex, preferably less than 0.1 dtex, more preferably from 0.03 dtex to 0 , 06 dtex are split and solidified, - At least one layer B is disposed on the first layer A, wherein the layer B has an open-pored pore structure having an average pore size of 1 to 1000 .mu.m, preferably from 10 to 100 .mu.m, in particular from 25 to 50 microns, If appropriate, at least one second layer A is arranged on the layer B, wherein the microfibers, microfilaments and / or elementary filaments of the first and / or second layer A at least partially penetrated into the pores of the layer B and with the microfibers, microfilaments and / or elementary filaments of the other layer A and / or in the Pores of layer B are devoured. Cleaning textile according to claim 1, characterized by the layer structure A (BA) _n BA, where n = 0 to 20. Cleaning textile according to claim 1 or 2, characterized in that the composite filaments of the first and / or second layer A have a cross section with an orange-like or "pie" called multi-segment structure. Cleaning textile according to one or more of the preceding claims, characterized in that the pie arrangement of the first and / or second layer A 8, 12, 16, 24, 32, 48 or 64 segments. Cleaning textile according to one or more of the preceding claims, characterized in that the layer B consists of an open-cell foam, a perforated film, a net-like textile fabric, woven fabric, knitted fabric, spacer knitted fabric, knitted fabric. Cleaning textile according to one or more of the preceding claims, characterized in that the layer B has a mean pore density of 1 to 1000 pores / mm ² . Cleaning textile according to one or more of the preceding claims, characterized in that the composite filaments comprise different filaments containing at least two incompatible thermoplastic polymers. Cleaning textile according to one or more of the preceding claims, characterized in that the proportion of the respective elemental filaments in the layer A advantageously more than 80 wt.%, More preferably 85 to 100 wt.%. is. Cleaning textile according to one or more of the preceding claims, characterized in that the microfiber composite sheet has a surface which is formed by the elementary filaments of the first and / or second layer A. Cleaning textile according to one or more of the preceding claims, characterized by a layer sequence A (BA) _n BA with n = 0 to 15, the layers A containing at least partially split pie 32 filaments and wherein the titer of the elementary filaments of the pie 32 filaments less than 0.1 dtex, is. Cleaning textile according to one or more of the preceding claims, characterized in that between the layers A and B at least one further layer, preferably designed as a reinforcing layer, for example as a scrim is arranged. Cleaning textile according to one or more of the preceding claims characterized by a symmetrical layer structure. A process for producing a cleaning fabric according to one or more of the preceding claims, comprising the following steps: - at least one fiber layer A, the nonwoven deposited microfibers having a mean titre of less than 1 dtex, preferably less than 0.1 dtex, still more preferably from 0.03 dtex to 0.06 dtex, in particular in the form of melt-spun and non-woven microfilaments and / or composite filaments, and / or at least one fiber layer A comprising a fiber component in the form of melt-spun and nonwoven composite filaments is spun, laid down to a nonwoven and optionally for example by needling, preconsolidated; It is provided at least one layer B, which has an open-pored pore structure with an average pore size of 1 to 1000 .mu.m, preferably from 10 to 100 .mu.m, in particular from to 25 to 50 microns provided; - The fiber layers A and B are arranged alternately to each other, preferably at least one outer layer is formed by the fiber layer A; - The layer composite is then subjected to mechanical solidification, in particular a hydrofluidic treatment, where appropriate, a splitting of the fiber component of the fiber layer (s) A takes place, which at least partially to elemental filaments having an average titer of less than 1 dtex, preferably less than 0th , 1 dtex, more preferably from 0.03 dtex to 0.06 dtex is split and solidified and wherein the microfibers, microfilaments and / or elementary filaments of the fiber layer (s) A at least partially penetrate into the pores of the layer B and with consume the microfibers, microfilaments and / or elementary filaments of the respective other layer A and / or in the pores of the layer B; - Assembly of the layer composite with formation of the cleaning fabric. Use of a cleaning textile according to one or more of the preceding claims for cleaning smooth surfaces.

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