DE10249290A1 - knitted - Google Patents

Abstract

The invention relates to a knitted fabric (1) with a vertical knitted structure and a horizontal weft insertion. The knitted structure and / or the weft insertion has conductive threads.

Description

The invention relates to a knitted fabric according to the generic term of claim 1.

Knitted fabrics stand next to woven goods and Knitted is a widely used form of manufacturing textiles The knitted fabrics are usually using warp knitting machines or Raschel machines with weft insertion manufactured.

Such knitted fabrics consist of a vertical knitted structure with a horizontal weft insertion. The vertical knitted structure consists of a mesh structure as well if necessary, standing threads incorporated into this.

Knitted fabrics produced in this way are used in numerous applications. An essential area of application forms the production of curtains. Due to the structural properties of the knitted fabrics, such curtains can be made transparent be and yet be largely non-slip.

The invention has for its object knitted fabrics to provide the type mentioned above, which with regard their functionality are expanded.

To solve this task are the Features of claim 1 provided. Advantageous embodiments and appropriate further training the invention are described in the subclaims.

The invention relates to a knitted fabric with a vertical knitted structure and a horizontal weft insertion, the knitted structure and / or the weft insertion having conductive threads.

Because of the becomes conductive threads an efficient shielding effect against electromagnetic fields receive. It also provides protection against electrostatic charges achieved.

This enables the knitted fabrics according to the invention to be used in numerous technical applications, in which rooms generally oppose the penetration of electromagnetic fields are protected should.

By a sufficiently dense mesh Arrangement of the conductive Threads can with the knitted fabric according to the invention closed shielding areas the electromagnetic waves are formed even at higher frequencies shield. Examples of this are waves emitted by cell phones or the like in the microwave range. The limit frequency of the shieldable frequencies is essentially through the grid spacings neighboring conductive Threads in Knitted fabric. The knitted fabric is only for electromagnetic waves permeable, whose wavelength smaller than the distances neighboring conductive Threads are. Grid structures with grids in the range of 1–10 mm inserted.

Furthermore, the knitted fabric according to the invention forms a contactable structure. This means that the knitted fabric is grounded can be shielded from low-frequency electromagnetic Fields possible is.

The structure of the knitted fabric according to the invention is advantageously designed such that at least part of the Weft insertion and / or part of the knitted structure standing threads of conductive Threads formed is while the knitted structure of the knitted fabric consists of non-conductive material.

The main advantage of this knitted fabric is that with a small proportion of conductive threads efficient electromagnetic shielding effect is obtained.

For the case that only the weft insertion or only the standing threads at least partly from conductive Threads formed are the conductive Thread a linear structure of essentially parallel conductive elements.

In a particularly advantageous embodiment there are both the weft insertion and the standing threads of the knitted fabric according to the invention at least partly from conductive Threads. In this case, a two-dimensionally networked structure of conductive elements obtained within the knitted fabric, by means of which a particularly efficient Shielding effect against electromagnetic fields is obtained.

In principle, the mesh structure could also be made conductive Threads formed be, which gives a particularly close-knit structure of the conductive threads would. However, this would to a significant increase of the manufacturing costs of the knitted fabric.

A major advantage of the extension consists in the provision of transparent knitted fabrics with electromagnetic Shielding effect. By a suitable specification of the mesh structure the formation of transparent knitted fabrics is possible, which is caused by conductive threads in the weft insertion and / or an efficient electromagnetic in the filament structure Have shielding effect with low material use on conductive threads. In addition, this structure ensures a high sliding resistance of the knitted fabric receive.

Such transparent knitted fabrics are suitable especially for the production of curtains or bed canopies, Mosquito nets and the like.

The knitted fabrics can also be used for production of work clothes, for example a transparent face protection, be used.

The conductive threads for producing the knitted fabric according to the invention can generally as metallic threads be trained. Non-metallic conductive threads, such as carbon threads, are also used.

Particularly advantageously, the conductive threads consist of a core yarn which has a core spun by sheath fibers, the core consisting of a metal-coated thread and the sheath fibers being formed by non-conductive fibers. The metal-coated threads can be designed as polyamide threads, polypropylene threads and the like.

A major advantage of this core yarn is in that the electrically conductive Component as part of the soul lies inside the core yarn and complete is enclosed by the sheath fiber.

On the one hand, this creates protection the metal layer of the soul achieved by the outer sheath fiber. In particular, abrasion of the metal layer on the polyamide threads Soul avoided.

Furthermore, by selecting the from non-conductive Fibers existing sheath fibers the surface properties of the core yarn be specified in a targeted manner. It is advantageous that the sheath fibers completely enclose the metal layers of the soul, so that the metal layers reflect the surface properties of the core yarn do not affect.

It is essential here that defies the protective effect of the sheath fibers, the conductivity not affect the soul of the core yarn.

The invention is explained below of the drawings explained. Show it:

1 : Schematic representation of an embodiment of the knitted fabric according to the invention having conductive threads.

2 : Schematic representation of a conductive thread designed as core yarn for the knitted fabric according to 1 ,

1 shows an embodiment of the knitted fabric according to the invention 1 , The knitted fabric 1 is produced in the present case using a Raschel machine with weft insertion. Such knitted fabrics are in principle 1 can also be produced using warp knitting machines with weft insertion.

The knitted fabric 1 according to 1 has a vertical knitted structure with horizontal weft insertion. The weft insertion consists of an arrangement of weft threads 2a . 2 B , In the present case, the knitted structure consists of a mesh structure with standing threads 3 , The standing threads 3 are typically worked into the knitted structure using a basic bar (laying rail).

The mesh structure exists in the present Case made of non-conductive Materials. In general, the mesh structure can be made from natural fibers, Synthetic fibers or mixtures thereof. The Mesh structure of continuous fibers, staple fibers or mixtures thereof be educated.

In the embodiment according to 1 is the mesh structure of polyester threads 4 educated. How out 1 can be seen, the knitted structure is designed such that on a vertical thread running in the vertical direction 3 two polyester threads each 4 consequences. The standing threads 3 run in a wave form in the vertical direction along the knitted fabric 1 ,

The management of the standing threads 3 can be varied if necessary. An essentially straight or right-angled meandering guidance of the standing threads 3 is possible.

The polyester threads 4 essentially also run in the vertical direction of the knitted fabric 1 , however, these also have almost horizontally running segments to form the mesh structure, so that they are threaded with the standing 3 form a networked structure. How out 1 the polyester threads run 4 in the area of the top weft 2a essentially parallel to this and cross a standing thread 3 , In the area of the second weft 2 B the polyester threads run 4 back in an essentially hortzontal direction, again cross the standing thread 3 and then continue in the vertical direction.

According to the invention, the standing threads exist 3 made of conductive threads and thus form one in the vertical direction of the knitted fabric 1 running conductive structure for shielding electromagnetic fields.

In principle, such a one-dimensional conductive structure is sufficient to achieve an electromagnetic shielding effect. In the present case, the shielding effect is increased in that part of the weft threads 2a consists of conductive threads, so that a two-dimensionally cross-linked conductive structure is obtained.

This in 1 illustrated knitted fabric 1 has a 1 full / 3 empty weft entry. In 1 are the needle positions 5 can be seen on which by means of needles, not shown, the polyester threads 4 can be used to form the mesh structure. How out 1 can be seen for each linear arrangement of the needle positions running in the vertical direction 5 every fourth needle position 5 with a weft 2a . 2 B evidenced by three free needle positions 5 consequences.

Every second weft thread 2a formed as a conductive thread, while the remaining weft threads 2 B consist of non-conductive material. In the present case, these weft threads exist 2 B like the mesh structure made of polyester threads 4 ,

In this way, a conductive network structure get that efficient shielding from electromagnetic Fields guaranteed. The gap sizes of this Network structures are advantageous to the wavelengths of the electromagnetic to be shielded Fields adjusted. The upper cutoff frequency is the shielding Fields determined by the gap size.

The network structure can be predefined in a simple manner by the type of weft insertion, in principle a full weft insertion is also possible. The present embodiment with the 1 full / 3 empty weft insertion is particularly suitable for the production of transparent knitted fabrics 1 , for example, for the production of curtains, bed canopies, mosquito nets or work clothes be used. For a given type of weft insertion, the network structure can be determined by the proportion of conductive weft threads 2a and non-conductive wefts 2 B be specified. Furthermore, the conductive network structure can be arranged by the arrangement of the standing threads 3 be specified.

The conductive threads can generally differ from structured metallic or metal-containing threads his. Silver or are also suitable as metals for forming the conductive threads Copper, tin, nickel or gold.

Furthermore, the conductive threads can at least partly also from non-metallic conductive materials, such as Carbon exist.

In a particularly advantageous embodiment, the conductive threads are core yarns 6 educated. The construction of such a core yarn 6 is in 2 shown.

The core yarn 6 consists of a soul and the surrounding sheath fibers 7 , The soul is from the sheath fibers 7 wound, whereby known spinning processes of all kinds can be used for this.

The soul of the core yarn 6 consists of a polyamide thread 8th which with a metal layer 9 are encased. The polyamide threads 8th the soul can be formed by monofilament or multifilament fibers. Alternatively, the core can also consist of a polypropylene thread.

The metal layer 9 is preferably homogeneous on the entire surface of the polyamide thread 8th applied. To apply the metal layer 9 electrochemical and wet-chemical processes in the field of electroplating are used particularly advantageously on the polyamide layer. In an expedient embodiment, the polyamide threads are first 8th so-called primers applied. This layer essentially forms an adhesion layer, on which metal clusters finally form the metal layer 9 be deposited. Alternatively, the deposition can also be carried out electrochemically by separating metal ions from an electrolyte liquid.

The thickness of the metal layers 9 on the polyamide threads 8th is preferably chosen so that the core of the core yarn 6 has a proportion of metal which is in the range of 10-15 percent by weight.

As metals for the coating of the polyamide threads 8th In principle, noble metals and base metals such as gold, copper, tin or nickel can be used.

The metal layer is particularly preferably 9 the soul of the core yarn 6 made of silver, with ultra-pure silver being used particularly advantageously for the coating.

The metal-coated and thus electrically conductive core of the core yarn formed in this way 6 is with the non-metallic sheath fibers 7 jacketed. These sheath fibers 7 can be freely chosen, in particular the selection of the sheath fibers 7 regardless of the material properties of the core of the core yarn 6 can be done.

The sheath fibers 7 can generally consist of natural fibers, synthetic fibers or mixtures thereof. Examples of natural fibers are wool, cotton, animal hair, cashmere or mixtures of such natural fibers.

In particular, fibers can be used as synthetic fibers Polyester or acrylic can be used.

Generally, the sheath fibers 7 also consist of hollow fibers, these consisting in particular of acrylic.

A major advantage of this core yarn 6 is that in addition to high conductivity values, it also has high elasticity. The high elasticity is particularly due to the use of polyamide threads 8th for the soul of the core yarn 6 receive. This elasticity is retained when coating with the respective metal. It is particularly advantageous if the metal in question has a high ductility, which is particularly high for silver.

The core yarns 6 accordingly have high elongations at break and a high rebound, with elongations of the core yarn 6 up to 20% are possible.

In the event that the soul of the core yarn 6 a metal layer made of silver or copper 9 has, the core yarn 6 also has antiseptic properties.

During the formation of the soul of the core yarn 6 the conductivity of the core yarn 6 specifies and in particular also other properties such as the antiseptic effect and elastic properties are determined by the sheath fibers 7 the surface properties of the core yarn 6 specified.

1

knitted

2a, 2 B

weft

3

filler thread

4

polyester thread

5

needle position

6

core yarn

7

clad fiber

8th

polyamide thread

9

metal layer

Claims (17)

Knitted fabric with a vertical knitted structure and a horizontal weft insertion, characterized in that the knitted structure and / or the weft insertion has conductive threads. Knitted fabric according to claim 1, characterized in that a predetermined proportion of the weft threads forming the weft insertion ( 2a ) by Leit capable threads is formed. Knitted fabric according to one of claims 1 or 2, characterized in that that the knitted structure has a mesh structure made of non-conductive material is formed. Knitted fabric according to one of claims 1 - 3, characterized in that the knitted structure has standing threads ( 3 ), which are at least partially formed by conductive threads. Knitted fabric according to one of claims 1-4, characterized in that that the conductive Threads at least partially made of metal. Knitted fabric according to claim 5, characterized in that silver, copper, tin, nickel or gold can be used as metals. Knitted fabric according to one of claims 1-4, characterized in that that the conductive Threads at least partially made of non-metallic materials, especially carbon, consist. Knitted fabric according to one of claims 1-6, characterized in that the conductive threads as core yarns ( 6 ) with one of sheath fibers ( 7 ) wound core are formed, the soul consists of metal-coated threads, and wherein the sheath fibers ( 7 ) are formed by non-metallic fibers. Knitted fabric according to claim 8, characterized in that the core is made of metal-coated polyamide threads ( 8th ) consists. Knitted fabric according to one of claims 8 or 9, characterized in that that the soul has a metal content of 10-15 percent by weight. Knitted fabric according to claims 8-10, characterized in that the sheath fibers ( 7 ) consist of natural fibers, synthetic fibers or mixtures thereof. Knitted fabric according to one of claims 1-11, characterized in that that its non-conductive components consist of natural fibers, synthetic fibers or mixtures thereof. Knitted fabric according to claim 12, characterized in that it's not conductive Continuous yarn components, staple fibers or blends thereof are formed. Textile surface consisting of a knitted fabric ( 1 ) according to any one of claims 1-13. Textile surface according to claim 14, characterized in that it is transparent is. Use of textile surfaces according to one of claims 14 or 15 for the production of curtains. Use of textile surfaces according to one of claims 14 or 15 for the production of bed canopies, mosquito nets or protective work clothing.