Background and Summary

BACKGROUND OF THE INVENTION

A. Field of the Invention

The present invention relates generally to a system that applies hydrophil ic coatings on wires in a quasi-continuous process. This allowing high-throughput manufacturing of respective devices. More specifically the invention concerns a system that applies hydrophilic coatings on sensing wires. Such a system is able to apply the specific coating in a continuous process or quasi-continuous process allowing high-throughput manufacturing of respective devices. This system is used to manufacture sensing wires that are applied for monitoring of potential ly defect structures suffering from e.g. adverse moisture ingress.

B. Description of the Related Art

Nowadays, the application of coatings for different kind of wires is usually performed by pressure extrusion performed at high temperature whereby thermoplastic coatings are appl ied on the respective wire-materials. There are however only a few industrial processes known where a high-throughput application of hydrophilic coatings is possible.

SUMMARY OF THE INVENTION

The present invention solves the problems of the related art by using a system whereby the wire is drawn through a vessel filled with the raw, aqueous coating material and which is dried afterwards by a hot airstream that is conducted by a ded icated pipe. The present invention also provides a method of coating a wire with an outer insulation coating and an inner conductive coating between said wire and outer insulation coating, characterised in that the to be coated wire comprises an outer material made of hydrophilic textile and further characterized in that this wire is passed through a first coating vessel comprising an aqueous medium comprising a water-solution of a conductive coating material, followed by a respective drying unit, thereafter through a second coating vessel comprising an solution of a non-conductive polymer coating material and finally again though a drying unit.

In another embodiment of the invention a method of coating a wire is provided the method comprising an outer material made of hydrophilic textile, characterised in that the to be coated wire is released over a bobbin into a first vessel comprising a comprising an aqueous medium comprising a water-solution of a conductive polymer coating material and further comprising a non-conductive material, 2) through an aperture at the bottom of said vessel, said outlet aperture having a diameter size value that is the value of the thickness of the wire and the thickness new coating, through 3) a first wire guide drying channel into 4) a second vessel comprising a comprising an aqueous medium comprising a water-soluble non-conductive material, 5) through an aperture at the bottom of said vessel, said outlet aperture having a diameter size value that is the value of the thickness of the wire and the thickness new second coating and 5) through a second wire guide drying channel onto a receiving bobbin. This techniques described above may be embodied as the receiving bobbin having a motorized computer steered function.

Some of the techniques described above may be embodied as a method whereby the wire is passed through a first coating vessel comprising an aqueous medium comprising a water- soluble synthetic polymer coating material and further comprising a titanium carbon nitride (TiCN) or titanium aluminium nitride (TiAIN or AITiN), thereafter through a drying unit, thereafter through a second coating vessel comprising an aqueous medium comprising a water-soluble synthetic polymer coating material and finally though a drying unit or some of the techniques described above may be embodied as a method, whereby the wire is passed through a first coating vessel comprising an aqueous medium comprising a water-soluble synthetic polymer coating material and further comprising graphite, for instance graphite particles, thereafter through a drying unit, thereafter through a second coating vessel comprising an aqueous medium comprising a water-soluble synthetic polymer coating material and finally though a drying unit.

In particular embodiment of the invention, the wire is passed through a first coating vessel comprising an aqueous medium comprising a water-soluble synthetic polymer coating material and a titanium nitride, thereafter through a drying unit, thereafter through a second coating vessel comprising an aqueous medium comprising a water-soluble synthetic polymer coating material and finally though a drying unit.

In yet another particular embodiment of the invention, the wire is passed through a first coating vessel comprising an aqueous medium comprising a water-soluble synthetic polymer coating material and further comprising titanium carbon nitride (TiCN) or titanium aluminium nitride (TiAIN or AITiN) or graphite or a combination thereof, thereafter through a drying unit, thereafter through a second coating vessel comprising an aqueous medium comprising a water-soluble synthetic polymer coating material and finally though a drying unit.

In another aspect, the method of present invention provides that the wire leaves the vessel at a lower outlet having a diameter which is only a few larger than the diameter of the wire, a layer being 1 to 5 mm.

In yet another aspect, the method of present invention provides that the vessel is filled with an aqueous coating material.

In yet another aspect, the method of present invention provides that the vessel is filled with an aqueous medium comprising a water-soluble synthetic polymer coating material.

In yet another aspect, the method of present invention provides that the wire after the coating vessel passes through a drying unit. Hereby the coating vessel the wire can pass through a drying unit which comprises a wire guidance channel or a drying pipe. Hereby the wire after leaving the vessel can be transported through a pipe where a hot airstream for instance trough an air drier. In yet another aspect, the method of present invention provides that the velocity of the wire transport is computer-steered and wire passes a wire guidance channel or a drying pipe with a length that is adapted so that the coating can sufficiently dry on its way through the pipe or guidance.

In yet another aspect, the method of present invention provides that the wire is passed through a first coating vessel leaving the first vessel through its outlet aperture, thereafter through a drying unit, thereafter through a second coating vessel leaving the second vessel through its outlet aperture and finally though a drying unit.

In yet another aspect, the method of present invention provides that the wire already covered with the dried functional coating is again transported through a second vessel with another aqueous coating material wire leaves the new vessel again at a lower outlet of the second vessel.

In yet another aspect, the method of present invention provides that the water-soluble synthetic polymer coating material is a water-soluble synthetic polymer is polyvinylalcohol (also known as PVOH, PVA, or PVAL).

In yet another aspect, the method of present invention provides that the polyvinylalcohol is crosslinked for enhancing water-resistance of the coating material.

By using the inventive method it is possible to produce textile wire that is at its elongate surface completely surrounded by the coating material.

By using the inventive method it is possible to produce textile wire that is at its elongate surface completely surrounded by the coating material in a continuous process and to have the textile comprising a conductive layer coat surrendered by a non-conductive outer or surface coat. Moreover by using the inventive method it is possible to produce coated textile wire high- throughput for instance to high-throughput produces wires coated with an hydrophilic coatings. In yet another aspect, the method of present invention provides that no pressure extrusion is used and the application is at room temperature.

In an advantageous embodiment, the method according to the present invention further comprises that the coated wire is winded-up at another for instance on a motorized bobbin.

Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.

Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.

Detailed Description

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Present invention involves an method for applying hydrophilic coatings comprising a bobbin which continuously releases the raw wire that is via a computer-steered motor transported through a vessel containing the raw, aqueous coating material. In this way, the wire is completely surrounded by the coating material. The wire leaves the vessel at a lower outlet having a diameter which is only a few larger than the diameter of the wire. This can furthermore comprise that the wire after leaving the vessel is freely transported through a pipe where a hot airstream is present created by a dedicated air drier. The velocity of the computer-steered wire transport and the length of the drying pipe is optimised that the coating can sufficiently dry on its way through the pipe. In a particular embodiment the wire already covered with the dried functional coating is again transported through a second vessel with another aqueous coating material, e.g. a new, protective coating. Also here, the wire is completely surrounded by the new coating material. The wire leaves the new vessel again at a lower outlet having a diameter which is only a few larger than the diameter of the coated wire.

Another particular aspect of the invention is that the wire after leaving the vessel is freely transported through a pipe where a hot airstream is present created by a dedicated air drier. The velocity of the computer-steered wire transport and the length of the drying pipe is optimised that the coating can sufficiently dry on its way through the pipe.

Particular suitable for the system of coating is a to use raw wire comprises an outer material made of hydrophilic textile enabling appropriate coating of the wire regarding its wetting properties and a homogenous distribution of the coating around on the wire surface.

Finally another aspect of the invention can be that the coated wire is winded-up at another, e.g. motorized bobbin.

Drawing Description

FIG. 1 is a graphic that shows the set-up of the mechanism where the coating with a sensitive material, such as Titaan Carbon Nitride (TiCN) and a water-soluble synthetic polymer such as Poly(vinyl alcohol) (PVOH, PVA, or PVAI). The graphic displays a deflection sheave 1, the first vessel 2 for coating material, the first pipe or channel with drying facility 3, the second vessel for coating material 4, the second pipe or channel with drying facility 5, the computer steered motorized bobbin for receiving the double coated wire 6 and the bobbin for receiving the raw or the to be coated wire 7. The values 400, 15, 100 and 40 are optional distances in cm.