WO2024110628A1

WO2024110628A1 - Data cable

Info

Publication number: WO2024110628A1
Application number: PCT/EP2023/082969
Authority: WO
Inventors: Johannes Böhm; Robert FRÜHWIRTH; Tobias Kupka; Marijan Rogic
Original assignee: Gebauer & Griller Kabelwerke Gesellschaft M.B.H.
Priority date: 2022-11-25
Filing date: 2023-11-24
Publication date: 2024-05-30

Abstract

Proposed is a data cable (1) for transmitting data in the telecommunications, information transmission or computer technology sectors, comprising two wires (2), wherein each wire (2) has - a conductor (3) and - an insulation layer (4), wherein the insulation layer (4) of each wire (2) has the same color additive comprising the same colorant. In order to allow improved signal transmission despite differently colored wires (2), the invention provides for an outer region (11) of the insulation layer (4) of one wire (2) to additionally have a further color additive comprising other colorants, and for an outer region (11) of the insulation layer (4) of the other wire (2) to be free of the further color additive and free of another color additive.

Description

DATA CABLE

FIELD OF INVENTION

The invention relates to a data cable for transmitting data in telecommunications, message transmission or computer technology, comprising two wires, each wire

- a leader and

- has an insulating layer, wherein the insulating layer of each core has the same color additive comprising the same colorants.

STATE OF THE ART

Data cables, especially those with high data transfer rates, usually comprise one or more pairs of wires and are used as a connection between a transmitter and a receiver, transmitting signals (electromagnetic waves) that are then further processed. Bidirectional communication is usually possible, i.e. the transmitter becomes the receiver and vice versa.

The signals can be transmitted either by means of differential signal transmission, which is a symmetrical transmission with antiphase signals, or by means of common-mode signal transmission, also a symmetrical transmission but with in-phase signals.

Each wire pair of a data cable comprises two conductors and two insulating layers, each of which surrounds one of the two conductors. In order to be able to process the wire pairs fully automatically, it is necessary that the two wires of a wire pair have different colors (externally), which is why the insulating layers are coated with corresponding colored layers. The different However, due to their ingredients, particularly their color pigments, colors in the color layers have different dielectric values, which mean that signals in the two wires propagate at different speeds and are attenuated differently. As a result, the propagation of the signals in the two wires over the length of the data cable is not symmetrical or is offset from one another. This means that, among other things, the signal propagation times are different, which impairs the transmission of the signals or data. This is known as mode conversion, which is usually one of the measures of how good the quality of the signal transmission is.

US 5 187 329 A, US 1 968 903 A, WO 2018/197365 A1, US 5 281 764 A and US 2010/307790 A1 all disclose cables with two cores, wherein the insulation layer of each core is surrounded by a colored layer, wherein the colored layers of the two cores have different colors.

TASK OF THE INVENTION

It is therefore an object of the present invention to provide a data cable for transmitting data in telecommunications, message transmission or computer technology, which overcomes the disadvantages of the prior art and enables improved signal transmission despite differently colored wires.

DESCRIPTION OF THE INVENTION

This task is carried out in a data cable for transmitting data in telecommunications, message transmission or computer technology, comprising two wires, each wire

- a leader and

- has an insulation layer, wherein the insulation layer of each core has the same color additive comprising the same colorants, solved according to the invention in that an outer region of the insulation layer of one core additionally has a further color additive comprising other colorants and an outer region of the insulation layer of the other core is free of the further color additive and free of a further color additive.

In the data cable according to the invention, the insulation layer of each core therefore contains the same color additive comprising the same colorants. In addition, the outer region of a core contains a further color additive comprising other colorants than those colorants contained in the color additive with which the insulation layer of each core is provided. The outer region of the other core is free of the further color additive comprising other colorants and free of all other color additives comprising the other colorants and/or other colorants. This means that the outer region of the insulation layer of the other core does not contain any further color additive. The outer region therefore only has the color additive and no other color additive.

The outer region of the insulation layer is therefore the region which is located furthest outward in a radial direction in the cross-section of the data cable according to the invention.

By adding the same color additive to the insulation layer of each wire, it is ensured that the properties of the wires, in particular the attenuation properties, remain the same - the wires are thus standardized or synchronized. By adding the additional color additive to the outer area of the insulation layer of one wire, it is ensured that one wire of the data cable according to the invention is optically visible in a different color than the other wire - this ensures fully automatic further processing. However, since only the outer area of the insulation layer of one wire is provided with the additional color additive (the outer area of the insulation layer of the other wire is free of the additional color additive and free of a further color additive), the signal transmission properties, in particular the attenuation properties, of this one wire are essentially unchanged or only slightly changed compared to the other wire. This means that in the data cable according to the invention, the signal transmission properties of the wires - despite the optical visibility of two different colors between the wires - are adapted to one another as far/as possible, which enables significantly improved signal transmission compared to the prior art. In other words, the coloring of the outer area of the insulation layer of one wire is sufficient to ensure fully automatic further processing, while at the same time the propagation time shift of the signals is only influenced as slightly as possible.

It is conceivable, for example, that the data cable according to the invention comprises two wires, the insulation layers of both wires being provided with the same color additive, which comprises white colorants. In addition, the outer region of the insulation layer of one of the two wires contains another color additive with green colorants. Thus, the two wires appear optically in different colors. One wire is optically visible as white, while the other wire appears optically green, although it is of course not excluded that other color combinations are used.

In this context, the term colorant refers to a color-imparting substance. For example, the colorants can be color pigments that are essentially insoluble in the application medium - in the context of this invention in the insulation layers - and act as

Solid particles are present, whereby the coloring is determined by Absorption and remission (scattering or reflection) of certain frequency components of visible light.

Of course, the color pigments can also be a mixture of "different" color pigments in order to achieve a certain color tone. It would also be possible to use (liquid) colorants that are soluble in the application medium, for example a polymer.

The color additives at least cause the insulation layers to be colored due to the colorants. However, both the color additive that all insulation layers contain and the additional color additive can of course also contain other additives in addition to the colorants, which means that the insulation layers can be optimally adapted to the respective application.

For example, the color additives can - in addition to the colorant - have a carrier material, anti-aging agent, dispersing agent, fillers, compatibilizers, light stabilizers, processing aids or lubricants and/or nucleating agents. The carrier material can be a polymer or a mixture of polymers that is usually identical to the application medium. Alternatively, it can also be a polymer or a mixture of polymers that is compatible with the application medium and has no significantly negative influence on its properties. Anti-aging agents are usually antioxidants that prevent or reduce degradation of the carrier material or all other ingredients of the color additives during processing and use. Dispersing agents make it easier to mix and distribute the colorants in the carrier material, while fillers, which are usually rock powder, increase the opacity of the color additives and improve their economic manufacture.

Compatibilizers are used to improve the compatibility of the color additives with the application medium and/or the better compatibility of the colorants with the carrier material. Light protection agents are UV stabilizers that prevent or reduce the degradation of the polymer and/or the colorants. Processing agents or lubricants can reduce "production pressure" in the machines and enable better processability. Nucleating agents are nucleating agents that influence the product properties of the end products. Of course, it cannot be ruled out that other additives, such as antistatic agents, antiblocking agents, optical brighteners, effect pigments, etc. are also intended.

Of course, it is not excluded that the data cable according to the invention has more than two wires. For example, the data cable can have three, four, five, six or even more wires, whereby the outer region of the insulation layer of at least one wire always additionally has the further color additive comprising other colorants and the outer region of the insulation layer of at least one other wire is free of the further color additive and free of a further color additive.

One factor that influences both the optical visibility of the different colors of the wires and the improved signal transmission is the thickness of the outer region of the insulation layers, in particular of the wire(s) that additionally contain the additional color additive. The outer region must be thick enough to provide sufficient volume for the additional color additive, in particular for the other colorants, so that the additional color additive, in particular the other colorants, can be sufficiently distributed, and on the other hand it must be thin enough to have as little influence as possible on the signal transmission properties, in particular the attenuation properties, of the wire, despite the addition of the additional color additive. Therefore, in one embodiment of the invention, it is provided that the outer region of the insulation layer of each wire has a Thickness of between 5 pm and 200 pm, preferably between 25 pm and 100 pm, particularly preferably between 40 pm and 60 pm. These thickness ranges represent the optimum in terms of sufficient coloring of one wire while at the same time only causing a slight delay in the signals.

In order to obtain a coloring of the one wire that is sufficient for fully automatic further processing, a further embodiment of the invention provides that the total composition of the insulation layer of the one wire comprises a maximum of 5% by weight, preferably a maximum of 3% by weight, particularly preferably a maximum of 1.5% by weight, of the additional color additive. These amounts represent the optimum for sufficient optical visibility and only a slight influence on the signal transmission properties, in particular attenuation properties, of the one wire.

In order to be able to produce the data cable according to the invention efficiently, in particular economically efficiently, a further embodiment of the invention provides that the insulation layer of each wire is produced by extrusion. By means of extrusion, it is possible to create various shapes with little effort and to process different materials reliably.

In a further embodiment of the invention, the insulation layer of each wire is made of polypropylene. Polypropylene is advantageous because the molecular structure, the height of the average molecular weight, the molecular weight distribution, the crystallinity and the spherulite structure can be varied within wide limits, which means that the properties can be influenced. Furthermore, the dynamic load capacity of polypropylene is high and qualifies the material for a wide range of applications. In addition, the dielectric constant and the dielectric loss factor are largely independent of the temperature. In a further embodiment of the invention, it is provided that the insulation layer of each wire

- an inner insulation layer covering at least part of an outer surface of the conductor, and

- an outer insulation layer which covers an outer surface of the inner insulation layer at least in sections, the outer insulation layer comprising the outer region. This means that both the inner insulation layer and the outer insulation layer of each core are provided with the same color additive comprising the same colorants. In addition, the outer insulation layer of one core comprises the outer region of the insulation layer, which outer region additionally has the further color additive comprising other colorants. In particular, the outer insulation layer consists of the outer region of the insulation layer.

The outer insulation layer gives the data cable according to the invention stability and serves as protection against the environment.

In particular, if parts of the insulation layers are made at least in sections from a foamed material, it is sometimes necessary to separate the foamed material from the conductors. Therefore, in a further embodiment of the invention, it is provided that the inner insulation layer of each wire

- an inner skin layer covering at least part of the outer surface of the conductor, and

- a main layer which covers the inner skin layer at least in sections.

It is conceivable that the main layer is made at least in sections from a foamed material and the inner skin layer is made from a different material, with the inner skin layer serving as a separation between the conductor and the main layer. That is, it delimits the Main layer in the direction of the conductor, provides a certain stability and adheres accordingly to the conductor.

A main layer made of foamed material ensures optimal transmission properties of the data cable according to the invention.

In a further embodiment of the invention, the data cable is a "shielded twisted pair" data cable. This variant of the data cable according to the invention has a shield, which very effectively prevents interference from entering the cable (or leaving it). In addition, the wires of at least one wire pair are crossed, twisted or stranded. The advantage of crossed, twisted or stranded wire pairs is that external noise or interference signals are coupled into both wires of the wire pair as evenly as possible. Coupled interference then changes the signals on the wires, but the difference between the signals is only slightly changed. A combination of braiding and shielding has proven to be very effective in reducing internal and external electromagnetic influences.

In a further embodiment of the invention, the data cable is a "shielded parallel pair" data cable. Here, the wires of at least one wire pair run essentially parallel to one another. At the same time, shielding is present. The advantage of this embodiment is that the data cable is very flexible due to the wires running parallel to one another, which makes it easy to lay.

In a further embodiment of the invention, it is provided that the data cable is an "unshielded twisted pair" data cable. This variant of the data cable according to the invention has twisted wires of each wire pair, but no shielding. This is the "simplest" version of a "twisted Pair" cable, with particular emphasis on the economic

Manufacturability is advantageous.

SHORT DESCRIPTION OF THE CHARACTERS

The invention will now be explained in more detail using exemplary embodiments. The drawings are examples and are intended to illustrate the inventive concept but are in no way intended to restrict it or represent it exhaustively.

It shows:

Fig. 1 is a schematic sectional view of a wire pair of a data cable according to the prior art;

Fig. 2 is a schematic mode conversion curve of the data cable according to the prior art;

Fig. 3 is a schematic sectional view of a wire pair of a first embodiment of a data cable according to the invention;

Fig. 4 is a schematic mode conversion curve of the first embodiment of the data cable according to the invention;

Fig. 5 is a schematic sectional view of a wire pair of a second embodiment of the data cable according to the invention.

WAYS OF IMPLEMENTING THE INVENTION

Fig. 1 shows a schematic sectional view of a wire pair, i.e. two wires 2, of a data cable 1 for transmitting data in telecommunications, message transmission or computer technology according to the prior art. of the technology. Each of the two wires 2 has a conductor 3 and an insulation layer 4 comprising an inner insulation layer 5 and an outer insulation layer 6, which is formed by an outer region 11 of the insulation layer 4, wherein the inner insulation layer 5 covers an outer surface 7 of the conductor 3 and the outer insulation layer 6 covers an outer surface 8 of the inner insulation layer 5. That is, the inner insulation layer 5 is arranged between the conductor 3 and the outer insulation layer 6.

So that the wires 2 can be processed fully automatically, they have different colors. One of the two wires 2 is optically visible in green (left wire 2 in Fig. 1), while the other of the two wires 2 is optically visible in white (right wire 2 in Fig. 1).

In order to achieve a different optical visibility of the two wires 2, the insulation layer 4 of one wire 2 is provided with green colorants (the green colorants are symbolized by the dots in the insulation layer 4) and the insulation layer 4 of the other wire 2 is provided with white colorants. This means that for both wires 2, both the inner insulation layer 5 and the outer insulation layer 6 contain different colorants.

These different colorants have different dielectric values, which cause the signals in the two wires 2 to propagate at different speeds and to be attenuated differently. This means that the propagation of the signals in the two wires 2 over the length of the data cable 1 is not symmetrical to one another, which means that, among other things, the signal propagation times are different. This is known as mode conversion.

Fig. 2 shows a mode conversion curve of the data cable 1 according to the prior art. Here, the TCTL parameter (Transverse Conversion Transfer Loss) is plotted against the frequency, whereby the TCTL parameter is a measure of the asymmetrical attenuation (ie mode conversion) of a data cable 1. This means that the lower the TCTL parameter, the better the attenuation properties of the data cable 1 and the better (more symmetrical) the signal transmission between the wires 2 of the data cable 1.

In Fig. 2, three lines are visible, namely a TCTL parameter 13 for each of the two wires 2 of the data cable 1 according to the state of the art and a limit line 12. In order to ensure good signal transmission, the TCTL parameters 13 of both wires 2 should be arranged below the limit line 12 in the entire frequency range. From Fig. 2 it can be seen that this is not the case with the data cable 1 according to the state of the art. Between 20 and 30 MHz, the TCTL parameters 13 of both wires 2 exceed the limit line 12 and then remain permanently above the limit line 12. This means that at frequencies greater than or equal to 20-30 MHz, the limit line 12 is exceeded by the TCTL parameters 13. This means that with the data cable 1 according to the state of the art, there are significant delay times of the signals in the two wires 2 in the higher frequency range - i.e. asymmetrical signal transmission takes place.

Fig. 3 shows a schematic sectional view of a pair of wires, i.e. two wires 2, of a first embodiment of a data cable 1 according to the invention. The structure of the first embodiment of the data cable 1 according to the invention, in particular the insulation layers 4, corresponds essentially to the structure of the data cable 1 shown in Fig. 1 according to the prior art. Although only two wires 2 are shown in Fig. 3, it is not excluded that the data cable 1 also has more wires 2, for example three, four, five, six or more wires 2.

However, the colouring of the insulation layers 4 is different. In the first embodiment of the data cable 1 according to the invention, the insulation layers 4 of the two wires 2, ie both the inner insulation layers 5 and the Outer insulation layers 6, which outer insulation layers 6 are formed from the outer region 11 of the insulation layers 4 and in the first embodiment have a thickness of essentially 50 pm, each have the same color additive comprising the same white colorants. In addition, the outer insulation layer 6 of one of the two wires 2 (left wire 2 in Fig. 3) comprises a further color additive comprising green colorants. The outer insulation layer 6 of the other of the two wires 2 (right wire 2 in Fig. 3) is free of the further color additive and free of a further color additive. Thus, one wire 2 is optically visible green (left wire 2 in Fig. 3) and the other wire 2 is optically visible white (right wire 2 in Fig. 3).

In this embodiment, the total composition of the insulation layers 4 of the two wires 2 each comprises 1% by weight of the color additive comprising white colorants. In addition, the total composition of the left wire in Fig. 3 comprises 1.78% by weight of the additional color additive, whereby the additional color additive in this case is composed of the same amount of white colorants and green colorants. This means that the additional color additive comprises the same amount of white colorants in addition to the green colorants. This means that the data cable 1 according to the invention can be further processed fully automatically and, on the other hand, the signal transmission properties of the wire 2, which is optically visible as green, are only slightly affected compared to the wire 2, which is optically visible as white.

The insulation layers 4 of both wires 2 of the first embodiment are made of polypropylene by extrusion.

Fig. 4 shows a mode conversion curve of the first embodiment of the data cable 1 according to the invention. Here again, the TCTL parameter is plotted against the frequency, just like in Fig. 2. In Fig. 4, three Lines are visible, namely a TCTL parameter 13 for each of the wires 2 as well as the boundary line 12 known from Fig. 2.

From Fig. 4 it can be seen that in the data cable 1 according to the invention the TCTL parameters 13 of both wires 2 are well below the limit line 12 over the entire frequency range. Thus, the signal transmission properties of the two wires 2 of the first embodiment of the data cable 1 according to the invention - despite the optical visibility of different colors (one wire 2 is optically visible green, the other wire 2 white) - are well adapted to one another, which enables a significantly improved signal transmission compared to the prior art.

Fig. 5 shows a schematic sectional view of a wire pair, i.e. two wires 2, of a second embodiment of the data cable 1 according to the invention. The second embodiment corresponds to the first embodiment of the data cable 1 according to the invention with the difference that the inner insulation layers 5 of the two wires 2 have an inner skin layer 9 and a main layer 10, the inner skin layer 9 being arranged between the conductor 3 and the main layer 10. The inner skin layer serves as a separation between the conductor 3 and the main layer 10 and provides stability.

Both the first embodiment of the data cable 1 according to the invention and the second embodiment of the data cable 1 according to the invention can be designed as a “shielded twisted pair” data cable 1, a “shielded parallel pair” data cable 1 or an “unshielded twisted pair” data cable 1. LIST OF REFERENCE SYMBOLS

1 data cable

2 core 3 conductor

4 I solat ions layer

5 Inner insulation layer

6 External insulation layer

7 Outer surface of the conductor 3 8 Outer surface of the inner insulation layer 5

9 Inner skin layer

10 Main layer

11 outer area of the insulation layer 4

12 Limit line 13 TCTL parameter of one of the wires 2 of the data cable 1

Claims

PATENT CLAIMS Data cable (1) for transmitting data in telecommunications, message transmission or computer technology, comprising two wires (2), each wire (2)

- a conductor (3) and

- has an insulation layer (4), wherein the insulation layer (4) of each core (2) has the same color additive comprising the same colorants, characterized in that an outer region (11) of the insulation layer (4) of one core (2) additionally has a further color additive comprising other colorants and an outer region (11) of the insulation layer (4) of the other core (2) is free of the further color additive and free of a further color additive. Data cable (1) according to claim 1, characterized in that the outer region (11) of the insulation layer (4) of each core (2) has a thickness of between 5 pm and 200 pm, preferably between 25 pm and 100 pm, particularly preferably between 40 pm and 60 pm. Data cable (1) according to one of claims 1 to 2, characterized in that a total composition of the insulation layer (4) of one wire (2) comprises a maximum of 5% by weight, preferably a maximum of 3% by weight, particularly preferably a maximum of 1.5% by weight, of the further color additive. Data cable (1) according to one of claims 1 to 3, characterized in that the insulation layer (4) of each wire (2) is produced by means of extrusion. Data cable (1) according to one of claims 1 to 4, characterized in that the insulation layer (4) of each wire (2) is made of polypropylene. Data cable (1) according to one of claims 1 to 5, characterized in that the insulation layer (4) of each wire (2)

- an inner insulation layer (5) which has an outer surface

(7) of the conductor (3) is covered at least in sections, and

- an outer insulation layer (6) having an outer surface

(8) of the inner insulation layer (5) at least partially covered, wherein the outer insulation layer (6) covers the outer region (11). Data cable (1) according to claim 6, characterized in that the inner insulation layer (5) of each wire (2)

- an inner skin layer (9) which covers the outer surface (7) of the conductor (3) at least in sections, and

- a main layer (10) which covers the inner skin layer (9) at least in sections. Data cable (1) according to one of claims 1 to 7, characterized in that the data cable (1) is a "shielded twisted pair" data cable. Data cable (1) according to one of claims 1 to 7, characterized in that the data cable (1) is a "shielded parallel pair" data cable. Data cable (1) according to one of claims 1 to 7, characterized in that the data cable (1) is an "unshielded twisted pair" data cable.