Electric or data transmission cables having high electrical conductivity and/or high data transmission speed.

FIELD OF THE INVENTION

The present invention relates to cables and a method for their production.

According to the present invention, by "cable" it is here intended to refer to the set including conductors, insulators, sheaths and protective or shielding reinforcements, specifically built to convey the current for both electricity transport and signal transmission.

The cables, according to the present invention, when compared to similar cables known in the art, are characterized by the fact that:

- they have a reduced skin effect;

- they can be used at higher frequencies (and therefore offer greater bandwidth)

- they have a higher capacity and/or speed of electricity conduction;

- they have a higher capacity and/or speed of signal conduction; and

- they can be made of materials cheaper than copper, for example in aluminium or non-metal materials (therefore, in this case, they are less likely to be stolen).

In Italy, for example, the thieves of electric copper cables cause (direct and indirect) damages for millions of euros per year.

BACKGROUND OF THE INVENTION

In WO2014/141071 a method is described for the preparation of coated metal foams (by an electrodeposition process) with a metal matrix and graphene.

In CN202384469 a radio frequency cable is described, characterized in that the inner conductor is composed of an aluminium core and externally a copper layer is deposited on the peripheral area of the aluminium core, therefore only copper is deposited on the outer layer (not with the electrodeposition method). In WO2015/041439 a coaxial cable is described which has a metal wire as its core, in which said metal wire is coated:

- by a first layer of " 'composite plating" having a mixture of a homogeneous or heterogeneous metal and a first graphene; and subsequently

- by a second layer of graphene deposited on the surface of the "composite plating" layer. US 2016/228964 claims an electrode for electrical discharge machines, comprising a core, preferably made of copper, brass, molybdenum, tungsten or steel, and a coating, wherein the coating contains graphene.

In the field, the need is felt to have economic cables available that are less likely to be stolen, and which exhibit better functional characteristics than the cables known in the art.

DESCRIPTION OF THE INVENTION

It has now been surprisingly found that cheap cables, better for energy and/or signal transport, when compared to those known in the art, are obtainable through the use of the process according to the present invention.

Therefore, the present invention relates to cables, useful for conveying the current for both electricity transport and signal transmission, characterized by the fact that they have a reduced skin effect; they have a higher electricity conduction speed; they have a higher signal conduction speed; they have a higher frequency band and have low production costs, and, when polymers or particular metal foams are used "poor/cheap in the building material" or metals having a value lower than copper, for example aluminium, they are less or not at all likely to be stolen.

The present invention also relates to a new method for the production of the cables described above.

According to the present invention, by "cables useful for conveying the current for both electricity transport and signal and/or data transmission" it is here meant to refer to "electric" cables that are useful for the electricity supply lines to towns, cables useful for electrical systems of industries and/or civilian homes, cables for transmission of data, (for example from and to a computer), mixed cables, for example useful for signals and data transport, such as those used for modern cameras, in which the same LAN cable is useful for both power supply and data transmission (text, images and/or voices ) from the camera to the receiver.

According to the present invention, the cables useful for conveying the current for both electricity transport and signal and/or data transmission consist of a core of metallic material, such as copper, aluminium, silver, gold, nickel or alloys and foams thereof; or in non-metallic material, such as a polymeric material selected in the group comprising polycarbonate (PC), polyethylene (PE), polyethylene terephthalate (PET), polymethylmethacrylate (PMMA), polypropylene (PP), polystyrine (PS), polyvinyl chloride (PVC), polyamide (PA), aery Ion i tri 1 e-butad iene-st yrene( A BS ) , polylactic acid (PLA) or polytetrafluoroethylene (PTFE) and a ceramic material.

According to the present invention the term "core" it is here meant to include a wire, conductor wire, a metal wire, a non-metallic wire, a wire in "metallic foam" (a non-limiting example of metal foams is reported in WO2014141071), a braided (as with the house copper wires) or not braided wire, a single or multiple wire, in a central or lateral position, a wire coated or not coated with isolating materials known in the art, a wire of any shape or size, for civil, industrial or domestic purposes and/or uses.

The "skin effect" is the tendency for alternating current (AC) to flow mostly near the outer surface of an electrical conductor, such as metal wire. This effect becomes more and more apparent as the frequency increases.

It is therefore an object of the present invention a cable useful for conveying the current for both electricity transport and signal and/or data transmission, comprising a core of metallic material selected from the group comprising: copper, aluminium, silver, gold and alloys or foams thereof; or a core in non-metallic material selected from the group comprising polycarbonate (PC), polyethylene (PE), polyethylene terephthalate (PET), polymethylmethacrylate (PMMA), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), polyamide (PA), acrylonitrilc-butadicnc-styrcnc (ABS), polylactic acid (PLA), polytetrafluoroethylene (PTFE), ceramic and mixtures thereof;

wherein:

a) said metallic or non-metallic core is coated with a first metallic layer, wherein the metal is selected from the group comprising: copper, aluminium, silver, nickel, gold and alloys or foams thereof, and wherein the first metallic layer is deposited on said core using a physical deposition technique (such as PVD - Physical Vapor Deposition) or a chemical deposition technique (such as CVD - Chemical Vapor Deposition) (as described in Adv. Mater. 2000, 12, No. 9);

b) on the first layer a) a second layer of metal and graphene is deposited, using the electrodeposition technique described in WO2014141071 , in which the metal associated with graphene may be the same or different from that used in the layer a) (for example, but not exclusively, copper, nickel silver or aluminium);

c) on the second metal and graphene layer b) a third metallic layer is deposited or stratified under the same experimental conditions used for layer a) , in which the metal used can be the same or different from that used for layer a) and/or layer b).

According to the present invention:

-when the core of the cable is metallic, the layer a) is optional,

-when the core of the cable is non-metallic, the layer c) is optional.

It is a further object of the present invention a process for preparing a cable useful for conveying the current for both electricity transport and signal transmission,

comprising:

a core in metallic material, selected from the group comprising copper, aluminium, silver, nickel, gold and alloys or foams thereof;

or: a core in a non-metallic material selected form the group comprising: polycarbonate (PC), polyethylene (PE), polyethylene terephthalate (PET), polymethylmethacrylate (PMMA), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), polyamide (PA), acrylonitrile- butadiene-styrene (ABS), polylactic acid (PLA), polytetrafluoroethylene (PTFE), ceramic materials and mixtures thereof;;

wherein said core is subjected to the following steps:

if it is a non-metallic core,

STEP la)

- the non-metallic wire is subjected to a physical vapor deposition procedure (PVD - Physical Vapor Deposition) or chemical vapor deposition (CVD - Chemical Vapor Deposition) of a first metal layer or its alloys, as non-limiting example aluminium, silver or copper; through the PVD/CVD procedure, a metallic layer is deposited on the surface of the non-metallic wire that flows from the unwinding coil to the winding coil; it is possible to adjust the amount of metal to deposit on the wire by adjusting the winding speed of the wire; the method used is well known in the art and described in http://www.mag-data om/dettagli-tecnici/introduzione-ai-film-polimerici/ Journal of Materials Chemistry C Volume 4 Number 37, 7 October 2016, Pages 8585-8830; and/or Adv. Mater. 2000, 12, No. 9;

STEP 2a)

- the non-metallic (metallized) wire obtained in STEP la) is subjected to an electrodeposition process of a second layer of metal and graphene, as described in WO2014141071;

STEP 3a)

- the non-metallic wire (metallized and activated with graphene) obtained in STEP 2a) is subjected to an electrodeposition process of a third layer of metal, as described in WO2014141071; or to a chemical or physical vapor deposition process using the PVD or CVD procedure, as described before for STEP la); if it is a metallic core,

STEP lb)

- the metal wire is subjected to a physical vapor deposition procedure (PVD / Physical Vapor Deposition) or chemical vapor deposition (CVD / Chemical Vapor Deposition) of a first metal layer or its alloys, for example aluminium; through the PVD/CVD procedure a metallic layer is deposited on the surface of the metallic wire that flows from the unwinding coil to the winding coil; it is possible to adjust the amount of metal to deposit on the wire by adjusting the winding speed of the wire; the method used is well known in the art and described in http://www.mag-data.com/dettagli- tecnici/introduzione-ai-film-polimerici/ Journal of Materials Chemistry C Volume 4 Number 37, 7 October 2016, Pages 8585-8830; and/or Adv. Mater. 2000, 12, No. 9.

STEP 2b)

- the metal wire (re-metallized for example with a more expensive and more conductive metal) obtained in STEP lb) is subjected to an electrodeposition process of a second layer of metal and graphene as described in WO2014141071.

STEP 3b)

- the metallized wire and activated with graphene obtained in STEP 2b) is subjected to a further electrodeposition process of a third layer of "metal or its alloys" as described in WO2014141071 ; or to a chemical or physical vapor deposition process using the PVD or CVD procedure as described in; Journal of Materials Chemistry C Volume 4 Number 37, 7 October 2016, Pages 8585-8830; and/or Adv. Mater. 2000, 12, No. 9.

By using these methods and steps, a cable is obtained useful to convey the current for both electricity transport and signal and/or data transmission, characterized by:

-showing a reduced skin effect (when compared to similar cables known in the art);

- having a higher capacity and/or speed of electricity transport;

- having a higher capacity and/or speed of signal and /or data transmission; - having a broader frequency band; and

- being less likely to be stolen.

Said cable can be suitably coated by one or more layers of insulating material using the methods known in the art.

It is a further object of the present invention a process for producing a cable useful for conveying the current for both transporting electricity and transmitting signals and/or data, comprising subjecting the metallic or non-metallic core (a wire) of such cable to the following steps: STEP 1)

on the wire a first metallic layer is deposited using the physical vapor deposition (PVD) or chemical vapor deposition (CVD) procedure;

STEP 2)

on the wire of step 1) a second metal and graphene layer is deposited, using an electrodeposition procedure;

STEP 3)

on the wire of step 2) a third metal layer is deposited using the physical vapor deposition (PVD), chemical vapour deposition (CVD) or electrodeposition procedure;

wherein:

- the metallic material of the wire is selected from the group comprising: copper, aluminium, silver, nickel, gold and alloys or foams thereof;

- the non-metallic wire material is selected from the group comprising: polycarbonate, polyethylene, polyethylene terephthalate, polymethyl methacrylate, polypropylene, polystyrene, polyvinyl chloride, polyamide, acrylonitrile-butadiene-styrene , polylactic acid , polytetrafluoroethylene and mixtures thereof;

- the metallic material of the first, second and third step is selected from the group comprising: copper, aluminium, silver, nickel, gold and alloys or foams thereof; - the metal of the first step may be the same or different from the metal of the second step, which in turn may be the same or different from the metal of the third step;

wherein:

when a copper metallic wire or a wire in a metal more conductive than copper is used, STEP 1) is optional;

and

when non-metallic wire metallized with copper, or with a metal more conductive than copper is used in the first step, STEP 3) is optional.

A further object of the present invention is a cable which is useful for conveying the current for both transporting electricity and transmitting signals and/or data, characterized in that it comprises at least one core made of metallic material and/or in non-metallic material;

wherein said core:

- is coated with a first metal layer deposited using the PVD or CVD technique;

- is further coated with a second layer of metal and graphene using an electrodeposition technique; - is further coated with a third metal layer deposited using the physical vapor deposition (PVD), chemical vapor deposition (CVD) or electrodeposition technique;

wherein:

- the metallic material is selected from the group comprising: copper, aluminium, silver, nickel, gold and alloys or foams thereof;

- the non-metallic material is selected from the group comprising: polycarbonate, polyethylene, polyethylene terephthalate, polymethyl methacrylate, polypropylene, polystyrene, polyvinyl chloride, polyamide, acrylonitrile-butadiene-styrene, polylactic acid, polytetrafluoroethylene and mixtures thereof;

- the metallic material of the first, second and third layer is selected from the group comprising: copper, aluminium, silver, nickel, gold and alloys thereof; - the metal of the first layer may be the same or different from the metal of the second layer, which in turn may be the same or different from the metal of the third layer;

wherein:

when a copper wire or a wire in a metal more conductive than copper is used, the first layer is optional; and

when a non-metallic wire metallized with copper or with a metal more conductive than copper is used in the first layer, the third layer is optional.

A further object of the present invention is a cable characterized in that:

- has a reduced skin effect;

- has a higher capacity and/or speed of electricity conduction;

- has a higher capacity and/or signal conduction speed;

- has a higher frequency band;

when compared to copper cables or other cables known in the art.

A further object of the present invention is a cable coated with one or more layers of polymeric and/or insulating material.

According to the present invention the cable:

can have a section of any geometric shape;

can consist of strands of wires;

can consist of coaxial conducting wires;

can be hollow (internally empty) or not hollow;

can have a section comprised between 0.1 mm to 40 mm ² .

According to the present invention, the thickness of the metal layer deposited by vapor or of the layer of metal and graphene range from 0.01 mm to 2 mm.

DETAILED DESCRIPTION OF THE INVENTION EXAMPLE 1 Process for the preparation of a cable useful for conveying the current for both transporting electricity and transmitting signals, in which a PVC wire is used as starting material.

STEP 1)

- the PVC wire is subjected to a vapour deposition procedure (CVD or PVD) of a first metallic layer in aluminium, copper or silver. Through the CVD/PVD procedure a layer of aluminium, copper or silver, is deposited on the surface of the non-metallic wire that flows from the unwinding coil to the winding coil (it is possible to adjust the amount of copper to deposit on the wire by adjusting the winding speed of the wire itself, as described in http://www.mag-data.com/dettagli- tecnici/introduzione-ai-film-polimerici/; Journal of Materials Chemistry C Volume 4 Number 37, 7 October 2016, Pages 8585-8830; d/orAdv. Mater. 2000, 12, No. 9), thus obtaining a metallized PVC wire.

STEP 2)

The metallized wire obtained at the end of the first step is subjected to a further electrodeposition process of a second layer of "copper (but not exclusively) and graphene" (as described in WO2014141071; as an alternative to copper, silver or another metal can be used indistinctly).

STEP 3)

The wire obtained at the end of the second step is subjected to a vapor deposition process (CVD or PVD) as described in the first step.

The wire thus obtained showed an improvement of 50-100% compared to traditional electric wires (in silver, copper or aluminium) not treated with the process according to the invention in the speed of data transmission, measured in bps (bit per second).

EXAMPLE 2

Process for the preparation of a cable useful for conveying the current for both transporting electricity and transmitting signals in which a metallic foam wire is used as starting material.

STEP 1) - the metallic foam wire is subjected to a vapor deposition procedure (CVD or PVD) of a first copper or silver metallic layer. Through the CVD/PVD procedure a layer of copper or silver, is deposited on the surface of the flowing wire (it is possible to adjust the amount of copper to deposit on the wire by adjusting the winding speed of the wire itself, as described in http://www.mag-data.com/dettagli- tecnici/introduzione-ai-film-polimerici/; Journal of Materials Chemistry C Volume 4 Number 37, 7 October 2016, Pages 8585-8830; and/or Adv. Mater. 2000, 12, No. 9) thus obtaining a wire in metal foam coated with a metal layer.

STEP 2)

The metallized wire obtained at the end of the first step is subjected to a further electrodeposition process of a second layer of "copper (but not exclusively) and graphene" (as described in WO2014141071; as an alternative to copper, silver or other metal can be used indistinctly).

STEP 3)

The wire obtained at the end of the second step is subjected to a vapour deposition process (CVD or PVD) as described in the first step.

The wire thus obtained showed an improvement of 50-100% compared to traditional electric wires (in silver, copper or aluminium) not activated by the process according to the invention in the speed of data transmission, measured in bps (bit per second).