EP2591156B1 - Thread, sheet material, insect screen, and method for producing a sheet material - Google Patents

Description

The present invention relates to a fabric, in particular fabric, knitted fabric and / or knitted fabric, for an insect screen with a number of arranged in a mesh structure threads, according to the preamble of claim 1.

The invention also relates to an insect screen.

Finally, the invention relates to a method for producing a fabric, which is designed as a fabric.

For the purposes of the present invention, the term fabric is understood as meaning manually or mechanically produced products of the weaving mill comprising at least two, in particular at right angles or nearly at right angles, crossed thread systems. The term knitted or knitted fabric is understood to mean knitwear in which a thread loop is looped into another. The knit, however, one stitch is made next to the other (thread runs horizontally, along a course), while the fabric of the thread overlying stitches forms (thread is perpendicular and forms a wedge with the adjacent thread) .Fäden, fabrics and methods of the aforementioned Species are in particular from the DE 100 53 229 A1 known. The fabric produced from the generic threads serve in an insect screen on the one hand as protection against the ingress of insects when the insect screen is mounted in a suitable manner behind an openable window. It is then, as is generally known, possible to open the window, for example for ventilation, without insects being able to enter the room.

In general, a fabric is clamped in a suitable frame, which is mounted behind the window frame for the production of the insect screen. In general, there is the requirement here that the fabric as a whole offers as high a permeability to light and air as possible and is as invisible as possible.

On the other hand, the known fabric can be used to achieve a filter effect against pollen. In order to achieve this effect, in the DE 100 53 229 A1 on the one hand proposed to dimension the free area of a mesh of the mesh structure of the known fabric in the range between 300 and 90,000 microns. For another thing is in the DE 100 53 229 A1 in order to achieve a filtering action against pollen, it is proposed to electrostatically charge the tissue. For electrostatic charging is proposed according to this prior art to rub a material on the tissue, the fabric, with a hair dryer, fan, fan or fan to flow through or to remove a full-surface attached to the fabric polymer film from the tissue. By the interaction of the selected dimensioning for the mesh size and the charging of the tissue, in the prior art, the filter effect against pollen can be achieved, taking advantage of the fact that the pollen are usually electrically charged.

A similar procedure is also from the DE 44 14 728 A1 previously known. In this document, it is proposed to form an electric field between the allergen and the tissue, which is to be used for filtration by charging net-like fabrics made of synthetic high polymer fibers.

A disadvantage of the known fabrics and the corresponding threads, however, is that the use is extremely uncomfortable, because the application of the charge must be repeated by the user frequently, depending on the ambient conditions. In particular, with an increase in air humidity or rain, the known tissue discharges at a disadvantage. For this case, see the DE 100 53 229 A1 that the fabric must be dried and then re-charged with a suitable polymer material by friction. Alternatively, to recharge the fabric, drying and recharging in one operation is suggested solely by the intensive passage of air through the fabric with particle-laden air when using a household blow dryer. However, the proposed measures are very impractical for the user at a disadvantage and require an active action.

Another disadvantage of the DE 100 53 229 A1 known mesh is that the mesh size is almost one order of magnitude smaller compared to tissues optimized only for insect protection, which adversely affects the air and light transmission and the desired largely invisibility of the tissue.

The US 2007/0123123 A1 discloses an insect screen in which polyester threads serve as a carrier material of the fabric.

The EP 0 886 031 A1 discloses a protective system for building openings in the form of an insect protection system.

The U.S. Patent 4,017,282 refers to a retentive mesh screen provided with a hydrophobic coating.

The EP 1 355 001 A1 makes a fabric for awnings with a method for its production previously known.

Finally she does US 2003/0207629 A1 coated textiles with hydrophobic property known.

Against this background, the present invention seeks to provide a fabric and an insect screen of the type mentioned above, which ensures effective protection against insects as well as pollen under different environmental conditions.

The present invention is also based on the object of proposing a method for producing such a fabric.

In a yarn for producing a fabric having a mesh structure, the yarn consists essentially of the triboelectric by a

Air flow chargeable carrier, which, in particular completely, is provided with a coating having a hydrophobic coating material. It has surprisingly been found that threads provided with a hydrophobic coating automatically self-statically charge in the air without the need for active charging. Such a thread is therefore eminently suitable for producing a fabric having a mesh structure for an insect screen. Because the self-chargeability and the likewise empirically observed long-term inhibition of a derivation of the electrostatic charge with a suitable choice of the carrier makes it advantageous to select the mesh size of a fabric prepared from the thread according to the invention for an insect screen in a customary for pure insect screens and yet not only a protection against insects but also to achieve a filtering effect compared to the much smaller pollen. Advantageously, the thread is thus also suitable for producing a fabric with the best possible light and air permeability with low visibility.

The aforementioned advantageous properties of the thread are achieved in particular if the carrier comprises a, preferably monofilament, polymer material, in particular polyester. In the context of the invention, however, in principle all materials which are guided in a position in a triboelectric series of voltages at a position other than air or conventional air-containing particles are suitable. Finding other suitable carriers will not cause problems for the skilled person within the scope of his skill.

In a preferred embodiment of the thread, the coating material comprises a fluoropolymer, in particular PTFE (Polytetrafluoroethylene). It has been found that this material is particularly suitable for the carrier with regard to the applicability to the carrier on the one hand and with regard to the hydrophobic effect on the other hand.

If the thread has a thickness selected from the interval 0.1 mm to 0.2 mm, one obtains an optimum in terms of the generally desired low visibility of the fabric on the one hand and the required strength of the fabric on the other side. Particularly suitable in this context, a thread thickness of 0.15 mm has been found.

The object directed to a fabric for an insect screen with a number of threads arranged in a mesh structure is achieved according to the invention by the combination of features of claim 1, wherein at least some of the threads are configured as above. In this way, according to the invention, the tissue can also have a filtering action against pollen, even if the mesh size significantly exceeds the typical dimensions of pollen, without the user having to take any active measures to charge the tissue electrically.

In particular, in an embodiment of the fabric according to the invention, a width of the mesh structure is at least 0.7 mm. Suitably, the mesh size is chosen so large that it is just below the Durchschlupfgröße that prevents disturbing insects from passing through the fabric, in particular tissue, to ensure the greatest possible air and light transmission under low visibility with low visibility of the fabric under this constraint ,

In the fabric according to the invention, it is provided that the stitch structure at bond points comprises warp threads and wefts consolidated by means of an adhesive, the adhesive comprising polyester resin in aqueous solution. It is achieved by such a solidification of the fabric that it is particularly stable in the cured state of the polyester resin. Polyester resins have the advantage in this context that they are hard and typically clear when cured. In addition, they are advantageously largely resistant to weak acid bases as well as gasoline and oil.

In an embodiment of the invention, the sheet may also be provided with a stiffening agent, in particular comprising a polyurethane dispersion, for stiffening the sheet.

Because the warp threads and / or the weft threads are roughened according to the invention, in particular by means of a finishing agent, this advantageously produces a mattness of the threads, which leads to the improved optical property with regard to the invisibility of the insect screen. Furthermore, the roughening advantageously ensures improved adhesion of the adhesive to the bond points. Under certain circumstances, the hydrophobic coating material or the coating comprising this coating material also adheres better to the carrier if a previous roughening of the carrier material is carried out.

In another preferred embodiment of the fabric according to the invention, the stitch structure at bond points comprises welded warp threads and weft threads. The welding of the warp threads with the weft threads at binding points On the one hand leads to a particularly good solidification of the fabric and on the other hand ensures that a cross-sectional area of the mesh is not reduced due to the solidification, such as excess adhesive. In addition, the welded bond points have the advantage that the adhesion of the hydrophobic coating material is not affected by any adhesive at the binding points, so that an undesirable derivation of the electrostatic charge in the region of the binding points can be effectively avoided with advantage.

The object is also achieved by an insect screen, which is characterized by a fabric fabric, according to one of claims 1 to 6.

The object directed to a process for the production of a sheet is solved by a process according to claim 8, wherein a substantially consisting of a triboelectrically chargeable by an air stream carrier, a hydrophobic coating substance coating is applied by the fabric by a with a container filled with the coating medium-filled medium is drawn. Preferably, the sheet passes through a well provided with the medium at a constant speed to wet the tissue with the medium. As a container, in particular, a foulard, as for comparable purposes from the textile industry to the competent expert is familiar.

The desired dispersion of the hydrophobic coating material on the substrate of the thread of the fabric for an insect screen is effectively achieved according to the invention, when the fabric by a den

Coating material is drawn in dispersion, in particular diluted with water, contained medium.

The method according to the invention additionally provides that the warp threads arranged in a mesh structure are welded at points of bonding with weft threads by means of ultrasound. As explained above, a very stable solidification of the fabric can be achieved hereby, without the effective mesh size at the bond points being reduced and without the adhesion of the hydrophobic coating on the support material of the threads in the region of the bond points, for instance as a result of interaction with an adhesive, is impaired.

As is known, heat is generated in the ultrasonic welding by a high-frequency mechanical vibration by friction between the threads to be welded, as known in the art. The ultrasonic welding has in connection with the inventive method has the advantage that can achieve low welding times.

In the method according to the invention, it is provided that the warp threads arranged in a mesh structure are bonded at points of bonding with weft threads by means of an adhesive, the adhesive being contained in the medium.

The invention will be described by way of example in an embodiment with reference to a drawing, wherein further advantageous details are shown in the figures of the drawing.

Functionally identical parts are provided with the same reference numerals.

Figur 1

Ein Insektenschutzgitter mit einem nicht erfindungsgemäßen Gewebe aus Fäden;

Figur 2

a. schematische Schnittansicht entlang der Linie II - II in Figur 1 des Gewebes in einer Ausführung mit verschweißten Bindungspunkten; b. Ausschnittsvergrößerung des Ausschnitts b. in Teil a. der Figur.

The figures of the drawing show in detail:

FIG. 1

An insect screen with a fabric of threads not according to the invention;

FIG. 2

a. schematic sectional view taken along the line II - II in FIG. 1 the fabric in a version with welded binding points; b. Detail enlargement of clipping b. in part a. the Figure.

In FIG. 1 is an insect screen 1 can be seen in a schematic representation. The insect screen 1 consists essentially of an insect screen fabric 2, which is enclosed in a frame 3 in unspecified manner, generally known manner. The insect protection fabric 2 is composed of in the FIG. 1 vertically running warp threads 4 and at a right angle to the warp threads extending weft threads 5. The terms warp threads and weft thread known refer to the manufacturing process during weaving. In the context of the present invention, however, it does not matter which threads are warp threads or weft threads or were in the production.

The warp threads 4 form with the weft threads 5 in each case at the crossing points binding points 6. The insect protection fabric 2 in FIG. 1 has a weave structure 7 in this way. The warp threads 4 and weft threads 5 are made of a carrier made of monofilament threads of PET (polyethylene terephthalate). On the construction of the threads 4,5 will be discussed below with reference to FIG. 2 discussed in more detail.

The FIG. 2 schematically shows a part of a section along the line II-II in FIG. 1 through the insect screen 2. The Thread thickness 8 of the warp threads 4 is 0.15 mm. Likewise, the thread thickness 9 of the weft threads 5 is 0.15 mm. A width 10 of the mesh 7 is 1.1 mm. The meshes have a square cross-sectional area. The free cross section per mesh is accordingly 1.21 mm ² . In the context of the invention, rectangular or any other shapes of the cross-sectional area are conceivable.

Next is in FIG. 2 to recognize that the insect protection fabric 2 is provided with a hydrophobic coating 11. The hydrophobic coating 11 is applied over the entire surface of both the warp threads 4 and the weft threads 5. The hydrophobic coating 11 consists of a fluoropolymer-containing dispersion. A particularly suitable material for the hydrophobic coating 11 is PTFE.

As in particular in FIG. 2b schematically indicated, the warp threads 4 are welded to the weft threads 5 in the region of the binding points 6. The hydrophobic coating 11 is also applied over the areas of the bonding points 6 without gaps in order to fully develop the water-repellent effect and to effectively prevent a discharge of the triboelectric charging. Since advantageously neither the welded connection between the warp threads 4 with the weft threads 5 nor the hydrophobic coating 11 projects into the loop 7, the mesh width 10 is practically not reduced. The permeability to light and air therefore remains according to the mesh size 10, without prejudice to the welding and without prejudice to the hydrophobic coating 11.

For the preparation of the insect protection fabric 2 for use in an insect screen 1 is a Ultrasonic welding process for producing the bonding points 6 and then a coating method using a padder used.

For this purpose, first the tissue is solidified by means of ultrasonic welding at the bonding points 6.

Subsequently, a dispersion of a fluoropolymer, especially PTFE, is applied to the ultrasonically welded fabric. As is known for comparable purposes in the textile industry, for example, a padder is used for this purpose. The fabric now passes at a constant rate with a provided with the fluoropolymer solution well. The insect protection fabric 2 is wetted with liquid. Subsequently, the insect protection fabric 2 is passed between two rollers that squeeze excess liquid from the tissue. The roll spacing is variable in order to adjust the pressure with which the excess liquid is squeezed out of the insect protection fabric 2.

Next, the approximately hand-moist tissue 2 is passed over a so-called clamping frame, which holds the tissue in the edge region by needle fixation so that the preset tissue dimension is kept exactly. Now, under the influence of heat air supply the insect protection fabric 2, the residual moisture is taken by condensation.

The result is a cured, clear film, consisting of the fluoropolymer, which effectively prevents a derivation of triboelectrically arising charge.

To improve the adhesion of the hydrophobic coating 11 is a roughening of the threads by treatment with a weak acid can be made. The advantage of roughening the threads is improved adhesion of the coating. The application of a wetting agent to the fabric, which is likewise possible within the scope of the invention, leads to a reduction in the surface tension of the hydrophobic coating 11 to be applied and thus advantageously counteracts disturbing windowing of the mesh.

In the context of the invention, it is equally possible to apply the hydrophobic coating before solidification of the tissue by means of ultrasonic welding.

The insect protection fabric 2 can thus be produced using the method.

The insect protection fabric loads with advantage as it were by itself, the charge is hardly dissipated. Because of this, the insect protection fabric 2 can advantageously have a filter effect against pollen despite a mesh size 10 of the mesh 7, which is significantly larger than typical expansions of pollen due to electrostatic effects.

LIST OF REFERENCE NUMBERS

1

Insect screens

2

Insect repellent fabric

3

frame

4

warp

5

weft

6

bonding point

7

mesh

8th

denier

9

denier

10

mesh

11

hydrophobic coating

Claims (9)

1. Fabric, in particular a woven fabric (2), warp-knitted fabric and/or weft-knitted fabric, for an insect screen (1), comprising a plurality of threads (4, 5) arranged in a loop structure, at least some of the threads (4, 5) substantially consisting of a substrate material, which can be triboelectrically charged by an airflow, and being completely coated with a coating (11) comprising a hydrophobic coating material, characterised in that the loop structure comprises warp threads (4) and weft threads (5) which are bonded to one another at bonding points (6) by means of an adhesive, the adhesive comprising a polyester resin and the warp threads and/or the weft threads being roughened.
2. Fabric (2) according to claim 1, characterised in that the substrate material comprises a, preferably monofilament, polymeric material, in particular polyester.
3. Fabric (2) according to either claim 1 or claim 2, characterised in that the coating material comprises a fluoropolymer, in particular PTFE.
4. Fabric (2) according to any of claims 1 to 3, characterised in that the diameter of the threads (4, 5) is selected from the range of from 0.1 mm to 0.2 mm.
5. Fabric (2) according to any of the preceding claims, characterised in that the loop structure has a width (10) of at least 0.7 mm.
6. Fabric (2) according to any of the preceding claims, characterised in that the loop structure comprises warp threads (4, 5) and weft threads (4, 5) which have been joined together at bonding points (6).
7. Insect screen (1) characterised by a fabric according to any of claims 1 to 6 which is designed as a woven fabric (2).
8. Method for producing a fabric according to any of claims 1 to 6, which is designed as a woven fabric (2) and comprises a number of threads (4, 5) arranged in a loop structure, a coating (11) comprising a hydrophobic coating material being applied to a thread (4, 5) which substantially consists of a substrate material which can be triboelectrically charged by an airflow, in that the fabric (2) is drawn through a container filled with a medium containing the coating material, characterised in that the warp threads and/or the weft threads are roughened as a result of being treated with a weak acid, and in that the warp threads (4) arranged in a loop structure are bonded to weft threads (5) at bonding points (6) by means of an adhesive, specifically a polyester resin in an aqueous solution, the adhesive being contained in the medium, and said warp threads and weft threads are preferably also joined by means of ultrasound.
9. Method according to claim 8, characterised in that the medium contains the coating material in dispersion, in particular diluted with water.

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