EP1357226B1 - Substrates with electrically conducting layers - Google Patents

Abstract

A substrate or film carries a layer of an electrically-conductive polymer. Independent claims are also included for (1) production of a substrate carrying an electrically-conductive layer by in-situ polymerization of a monomer or pre-polymer or by application of a polymer dispersion; (2) apparatus for applying the polymer dispersion, the monomer solution or the monomer/initiator or catalyst mixture in a solvent, the apparatus comprising a temperature-controlled application tank, plunge cylinder, application roller or printer; and (3) a magnetic pigment composition for use with the electrically-conductive product, the composition comprising pigments based on iron oxide, iron, nickel-cobalt or alloys, barium, cobalt-ferrite or hard or soft magnetic iron or steel in aqueous, solvent-free or solvent-containing dispersions such as nitrocellulose, acrylate polymer dispersions of mol. wt. 150,000-300,000, acrylate-urethane dispersions or acrylate-styrene or PVC (co)polymer dispersions.

Description

The invention relates to substrates with electrically conductive layers, methods and apparatus for their preparation and their use.

In the production of coated substrates, conductive paints or lacquers are usually used for printing electrically conductive layers. In general, electrically conductive pigments, for example carbon black, graphite, silver and the like, are added to the paints or lacquers. However, the paints and varnishes provided with these pigments are clearly visible after printing, especially on transparent substrates.

In various applications, however, it is undesirable that the applied electrically conductive layers are immediately recognizable. This applies in particular to the use in security features for data carriers, value documents and products of all kinds.

Out EP 0 426 801 B For example, security elements for security documents are known, which have characters that are hidden in incident light, visible in transmitted light and which are also electrically conductive, wherein the electrically conductive material over the entire surface over at least one surface of the security element is present and transparent or semitransparent at least in some areas is executed and arranged above and / or below the characters. The electrically conductive material is always located on the surface of the security feature. In this case, the transparent or semitransparent material is realized either by an indium tin oxide layer or by sputtering a metal layer, in particular an aluminum layer.

However, in particular for security applications, certain requirements are to be placed on the electrically conductive layer, in particular for a reliable function and identifiability of the electrically conductive features the electrical resistance, the mechanical resistance, the flexibility, the ductility, the temperature and chemical resistance, which can not be satisfactorily achieved with the known solutions. In particular, when used as RF antennas for transponders, in anti-theft labels, smart cards and the like, a secure function must be ensured. US 5 176 405 A describes security documents with an embedded security feature that is partially transparent and electrically conductive. In this case, an electrically conductive plastic material can be used. WO 02/05360 A teaches methods for producing organic field effect transistors which are used as identification features by printing functional polymers on a substrate.

The object of the invention is therefore to provide a method for producing security elements with invisible, preferably transparent, electrically conductive layers, which additionally have the above-mentioned desired properties.

The invention relates to a method for the production of security elements comprising a carrier substrate are applied to the electrically conductive layers, characterized in that the monomer ethylenedioxythiophene (EDT) is applied to the carrier substrate and is polymerized in situ using the initiator Fe (III) toluenesulfonate wherein monomer and initiator are applied in a weight ratio of 1:20 to 1: 100 and the monomer is applied with subsequent application of the initiator and / or catalyst or already mixed with the initiator and / or catalyst, wherein an electrically conductive layer of Polyethylenedioxythiophene (PEDT) which is stabilized by the non-polymer bound toluenesulfonate anion

Polyethylene dioxythiophene is used as the electrically conductive polymer.

The polymer is applied to a carrier substrate in the form of its monomer with subsequent application of an initiator and / or catalyst or already in admixture with an initiator and / or catalyst.

The application of the monomer (s) in admixture with the initiator and / or catalyst can be accomplished in any known conventional manner For example, by spin-coating, brushing, vapor deposition, by printing, (gravure, flexographic, screen, offset, digital and the like) by spraying, sputtering or roll coating techniques.

Carrier substrates are, for example, carrier films, preferably flexible transparent plastic films, for example of PI, PP, MOPP, PE, PPS, PEEK, PEK, PEI, PAEK, LCP, PEN, PBT, PET, PA, PC, COC, POM, ABS, PVC in question.

The carrier films preferably have a thickness of 5 to 700 μm, preferably 5 to 200 μm, particularly preferably 15 to 50 μm.

Furthermore, metal foils, for example Al, Cu, Sn, Ni, Fe or stainless steel foils having a thickness of 5-200 μm, preferably 10 to 80 μm, particularly preferably 20-50 μm, may also serve as the carrier substrate. The films can also be surface-treated, coated or laminated, for example, with plastics or painted.

Further, as carrier substrates also paper or composites with paper, for example, composites with plastics with a basis weight of 20 - 500 g / m ^2, preferably 40 - ² are used 200 g / m.

Furthermore, woven or nonwovens, such as continuous fiber webs, staple fiber webs and the like, which may optionally be needled and / or calendered, can be used as the carrier substrates. Preferably such fabrics or webs of plastics, such as PP, PET, PA, PPS and the like, but it can also be woven or nonwovens made of natural, optionally treated fibers, such as viscose fibers are used. The nonwovens or fabrics used have a weight per unit area of about 20 g / m ² to 500 g / m ² . If necessary, the nonwovens or fabrics must be surface-treated.

In Fig.1 a special arrangement for applying the conductive polymers (as a mixture of monomer and initiator and / or catalyst) is shown. In Fig.2 a further possibility of the application of the monomer and the initiator and / or catalyst is shown, in Figure 3 a possibility for applying two successive layers of the electrically conductive polymer, in Fig. 4 a scheme for the treatment of the washing liquid and in Fig. 5 and Fig. 5a an inventive embodiment of the application device with reservoir and separate provided as Zudosiereinheiten storage containers.

In the Fig. 1 to 3 2 means a storage vessel for the mixture of the monomer with the catalyst or for the monomer, 2a the catalyst application device (if only the monomer is provided in the storage vessel 2), 2b the storage vessel for the application of the second polymer layer, 3 6 a washing area with the following simultaneously or alternatively usable units 6a spray nozzles, 6b a brush or a felt and 6c an air knife and 7 an optional blow bar or a spray bar, 4 a squeegee, 5 a drying device (IR, UV or convection dryer) Dryer.

In Fig. 4 8 means water treatment (also adding ions in the form of salts), 9 a pressure control, 10 a pump, 11 the washing process, 12 a filter, 13 - 17 ion exchangers, 18 the sanitation.

In the Fig. 5 (Non-inventive embodiment) and 5a is a preferred application device (2 or 2b, and 3 as in the Fig. 1-3 shown) with associated in detail hereinafter described additional plunger cylinder 3a. In the preferred application device, the storage vessel 2 or 2b consists of an outer tub 21 and an inner tub 22 with a return plate 22a. 23 means the feed of the monomer / initiator and / or catalyst and / or catalyst mixture from a supply (mixing) container 23a via a pump 23b and a filter 23c, 24 means the outflow of the monomer / initiator and / or catalyst and / or catalyst mixture from the outer tub 22 in the reservoir. 3a means a dip cylinder and 3 the transfer cylinder. 25 denotes a distributor tunnel for the monomer / initiator and / or catalyst and / or catalyst mixture, 26 the distributor plate of the distributor tunnel.

In Fig. 5a 27 means the reservoir for the monomer and 28 the reservoir for the initiator and / or catalyst and 29 the reservoir for the solvent.

It is preferably as in Fig. 5 shown from a reservoir 23a, which is preferably double-walled and is temperature-controlled to set a corresponding temperature, via a pump 23b and a filter 23c in the temperature-controlled inner tub 22 of the reservoir 2 (off Fig. 1 ). In the inner tub, the dispersion is evenly distributed via a distribution tunnel 25 and the distributor plate 26, which is provided with regularly arranged openings.

Through the filter possible impurities are retained.

The inner tub has on the inner surface of the shape of an approximately half-cylinder, wherein this surface is dimensioned so that the plunger cylinder 3 a can engage in a defined constant distance from the inner surface of the reservoir 2. Depending on the height of the filling in the inner tub 22, the dip cylinder 3a engages with about 1/3 1/2 of its circumference into the dispersion conveyed into the inner tub. The temperature-controlled inner tub is dimensioned so that it on the side facing away from the drain 24 of the surrounding temperature-controlled outer tub side in about the dimension of a half-cylinder, but whose shape substantially continuing return plate up to a height of at least half of the diameter up to about 2 / 3 of the diameter of the submerged cylinder. The dip cylinder now takes the dispersion from the inner tub and transfers it to the transfer cylinder. In this case, the excess dispersion, which is not absorbed by the transfer cylinder, now runs back into the outer trough 21 via the outside of the inner trough. Likewise, that polymer dispersion fraction which passes over the doctor blade 4 (in FIG Figure 5 not shown) was not applied to the application tool, back into the outer tub.

Due to the orientation of the outer tub not plan in a plane, but with a slight slope from the side facing away from the drainage side of the paint pan to the side on which the drain is located, the collected in the outer tub 21 dispersion from the entire Lackauftragswerk back into the Reservoir 23 a guided. In the inner tub is thus always only from the reservoir under a defined temperature and with the inflow speed defined by the pump 23 b introduced dispersion.

By avoiding the return of dispersion, which is not applied via the following cylinders and the doctor blade, into the inner tub, the temperature of the dispersion in the inner tub is kept correctly constant and air ingress is avoided. Furthermore, the temperature of the dispersion in the inner tub can be continuously monitored via a temperature sensor (in Figure 5 not shown).

The drying of the applied dispersion is then carried out by the drying devices 5 or the washing process in the washing station 6 for the removal of solvent residues ( Fig.1 )

The monomers or prepolymers are applied to form the electrically conductive polymers and polymerized in situ ( Fig. 2 . 3 . 5 and 5a ).

Both free-radical and redox or photo initiators and / or catalysts, for example UV initiators, can be used as the initiator and / or catalyst.

Both monomer and initiator and / or catalyst are preferably provided in a solvent or dispersing agent, for example in an alcohol such as propanol or n-butanol.

Optionally, in addition, a catalyst for accelerating the reaction may be added, for example, a Ziegler-Natta catalyst, or a Pt catalyst, in which case optionally, the added amount of initiator and / or catalyst may be lower.

In one embodiment, as in FIG Fig.2 represented, the monomer provided in the storage vessel 2 and, if appropriate, analogous to in Fig. 5 illustrated embodiment of the application device are applied to the carrier substrate. The initiator and / or catalyst and / or catalyst or optionally the additional catalyst is provided in storage vessel 2a and applied to the monomer present on the carrier substrate, wherein an excess of initiator and / or catalyst is applied to complete polymerization of the polymer achieve, as described in detail in the following particularly preferred embodiment. After the polymerization, in turn, the drying process, the washing process and optionally a further drying process (as described in more detail in the following particularly preferred embodiment of the process according to the invention) take place.

In the particularly preferred embodiment, the corresponding monomer is preferably mixed with the initiator and / or catalyst (and optionally with an additional catalyst) and applied to the carrier substrate (analogously Fig. 1 , wherein in the storage vessel 2, the monomer / initiator and / or catalyst mixture is provided).

The preferred embodiment of the applicator has, as in Fig. 5a shown, in addition to the in Fig. 5 elements shown in each case a reservoir for the monomer and a separate reservoir for the initiator and / or catalyst or the initiator and / or catalyst or Zusatzl. Catalyst mixture and for the optionally additionally metered in solvent. Preferably, the solvent is metered in via a viscosity regulator.

It is also possible to provide a solution of monomer or prepolymer and initiator and / or catalyst in a storage container and, in a second storage container, the solvent to be optionally metered in.

The monomer / initiator and / or catalyst mixture is then in (strong) dilute solution in this case.

The initiator / catalyst used is Fe (III) toluenesulfonate. Fe (III) toluenesulfonate is a free-radical initiator or catalyst which simultaneously initiates a redox reaction during the polymerization. The Fe (III) ion acts as an initiator and the toluenesulfonate forms the matrix in the conductive polymer.

Thus, if ethylenedioxythiophene as the monomer, for example Baytron ^® M or Baytron ^® M-V2 of the Fa. Bayer, and Fe (III) -toluenesulfonate, for example Baytron ^® C-types, for example Baytron ^® CB-40 from Bayer, as initiator and / or catalyst used, the polymer present on the carrier substrate after the polymerization is polyethylene dioxythiophene / toluenesulfonate (PEDT-TS, P-DOT).

In order to avoid any dangerous residues in the conductive layer of the initiator and / or catalyst, ie in particular Fe (III) toluenesulfonate, eg Baytron ^® CB 40, the Fa. Bayer in large excess compared to the monomer resp. Prepolymer used (eg ethylenedioxythiophene, such as Baytron ^® M or Baytron ^® M-V2 from Bayer). The weight ratio of monomer or prepolymer to initiator and / or catalyst is thereby 1:20 - 1: 100, preferably 1:50 to 1:80. The excess initiator and / or catalyst ensures complete and safe reaction of the entire monomer even during shorter available reaction times, thus ensuring that no deleterious residues remain. Furthermore, optimum film formation is achieved by this excess of initiator and / or catalyst.

In the method according to the invention, therefore, the pure substances (monomer, initiator and / or catalyst) are used without the addition of further binders and / or additives.

The polymerization takes place depending on the solvent used already at the time in which a temperature is reached, which causes evaporation of the solvent. In order to avoid premature or excessive polymerization prior to application to the carrier substrate in the storage vessels, or too rapid polymerization immediately after application to the carrier substrate, depending on the temperature prevailing in the storage vessels advantageously from the provided reservoirs monomer or solvent is metered in as needed via a pump, care should be taken during the addition of the solvent (for example, an alcohol such as propanol or n-butanol) that remain after the polymerization is not large amounts of solvent in the layer, which subsequently must be removed, so a balanced metering takes place. Preferably, however, the undesired polymerization is controlled by metering in the monomer, which is highly diluted in the solvent

Alternatively, an early polymerization can also be prevented by the exact control of the temperature in the storage containers and in the commissioned unit, wherein the immersion cylinder or transfer and application cylinder should possibly be cooled or heated.

In one according to the Fig. 5 and 5a designed applicator is therefore controlled by adjusting the ratios of the mixture components or the temperature of the reaction kinetics and at the same time achieves a uniform homogeneous application of the monomer solution or the monomer / initiator and / or catalyst mixture.

Depending on the solvent used, the polymerization takes place at temperatures of 50-150 ° C., preferably at 80-120 ° C.

Initiator and / or catalyst excess and optionally catalyst residues and other contaminating reaction products can also be removed in situ or optionally subsequently by treatment with a solvent, for example water, deionized water, deionized water, alcohols such as ethanol, propanols, butanols and the like or Water / solvent mixtures are removed from the layer.

Preferably, the initiator and / or catalyst excess is removed by water, which is treated, for example, by reverse osmosis, ion exchangers, distillation or physical water treatment plants.

The reaction can be influenced during the washing process by a defined adjustment of the ion content of the water, in particular the content of alkali and / or alkaline earth metal ions. Attachment of the ions present in the water to the O atoms of the ethylenedioxythiophene units forms complexes, which changes the configuration of the macromolecules and thus shifts the band gap in the absorption spectrum and thus the absorption maximum.

At the same time, the conductivity is variable by this complex formation and can therefore be defined by the content of ions in the water defined.

The water prepared as described above is therefore optionally adjusted to a defined ion content by addition of alkali and / or alkaline earth metal ions in the form of salts, for example sodium salts, for example NaCl or alkaline earth salts such as Mg salts, for example MgCl ₂ .

The washing process is preferably carried out by applying the selected washing liquid by means of one or more nozzle bars, wherein preferably pressure and angle of the washing liquid impinging on the coating are adjustable.

The excess water on the polymer coating is removed by squeezing, wiping, drying, by suitable means such as squeezing devices, drying devices, air knife, or suction units and fed to a recycling cycle.

The effluent from the process water is preferably circulated, where appropriate, if necessary, fresh water can be added. Wastewater saturated with initiator or initiator and catalyst is treated via a filter system and then via ion exchangers and / or by distillation. In order to ensure continuous operation, it is further preferred to use a group of several, preferably 1-5, ion exchangers, for example at least one ion exchanger being in operation, another in stand-by mode and another in regeneration mode.

If necessary, finally, a washing process with pure, as described above recycled, fresh water can be connected.

If desired, highly volatile constituents can also be removed by drying with an IR dryer, a convection dryer and the like.

Depending on the use, the electrically conductive polymer layers may each have a thickness of 0.1-50 μm, preferably 0.5-10 μm. For certain uses thinner layers of 0.001 to 50 microns, preferably 0.05 to 10 microns are readily produced.

Furthermore, the layers according to the invention are excellently conductive. The extensibility of the layer can be variably controlled depending on the polymerization process.

The electrically conductive polymer layers are generally temperature-resistant, it may possibly temperature resistances of> 100 ° C can be achieved.

If desired, a transparency of> 80% can be achieved with the electrically conductive polymer layers according to the invention.

The electrically conductive polymers can also be pigmented, all known pigments being suitable. If the transparency is not to be significantly influenced, however, highly opaque or coloring pigments such as carbon black or graphite are not suitable.

The proportion of pigments in the solid state can be up to 40%.

Optionally, the carrier material may be previously treated with a coupling agent to improve the adhesion of the conductive polymer used. In general, however, especially when using the in situ polymerization of the monomers or prepolymers, the adhesion of the electrically conductive polymers on all carrier substrates is quite more than satisfactory.

The electrically conductive polymers can be present both on the entire surface as well as partially on the carrier material.

The application of the electrically conductive polymers can be carried out according to one of the described embodiments of the method in the form of characters and patterns, flat or linear, wavy or zigzag and similar or analogous structures, such as guilloches, longitudinally and / or transversely to the machine direction of the substrate.

Line-shaped or analogous structures have a conductivity directed in a preferred direction according to the orientation of the structures. In addition, these structures provide additional security against destruction by transverse cracks in this and possibly above and / or underlying layers, since these are prevented from tearing at the interstices. If such an electrically conductive layer is protected by an additional layer, for example a lacquer layer or by lamination, the gaps or recesses ensure improved sealing of the conductive polymer layer.

If appropriate, these structures also represent a 2-dimensional coding.

Although the electrically conductive polymeric layers are very stable mechanically and thermally, but may be sensitive to moisture, these layers are preferably not directly on the surface of the substrate.

In one embodiment, for example, line-wave-shaped or zigzag-shaped structures or guilloches may be connected to increase the line cross-section via cross-connections which may have different widths or shapes and may also be arranged at different angles to the basic structure.

The widths of the lines, waves or zigzag structures or guilloches can be, for example, 0.05-10 mm, preferably 0.1-0.3 mm, those of the cross-connections 0.5-100 mm, preferably 1-10 mm.

The electroconductive monomers can be applied in any known conventional manner, for example by spin-coating, brushing, vapor deposition, by printing (gravure, flexo, screen, offset, digital, and the like) by spray, sputter, or roller application techniques.

For partial application, a solvent-soluble paint or a soluble paint can be applied to the carrier substrate or any layers already thereon. Subsequently, the conductive polymer is applied to this layer, whereupon the soluble color in the uncoated areas is removed by means of the appropriate solvent, optionally with mechanical assistance.

However, it is also possible first to apply a suitable adhesion promoter partially in the desired form to the carrier substrate, then to apply the electrically conductive polymer over the entire area, whereupon the polymer is applied in those areas where no adhesion promoter is present by appropriate measures based on the basic adhesion are matched to the electrically conductive polymer, can be replaced again.

Furthermore, the partial application can also after the in the DE 100 25 522 A1 described method.

The electrically conductive polymer layer can also be adjusted to be adhesive or releasable.

In order to increase the conductivity, it is also possible for the time being to apply a layer of the electrically conductive polymer and then to apply a further layer of the electrically conductive polymer by in situ polymerization. Furthermore, the electrically conductive polymer layers according to the invention can also be used preferably in conjunction with an inorganic one metallic or pigmented conductive layer can be applied particularly advantageous. Not only is there an improvement in the electrical conductivity of the coated substrate but also an additional assurance of proper function and identifiability.

Due to the better extensibility of the electrically conductive polymers, malfunctions that can occur as a result of fine and very fine cracks in the inorganic conductive layer can be bridged by the electrically conductive polymer layer.

A multilayer construction of a full-area or partial layer of a conductive polymer having linear, wavy, and the like structures of the same polymer printed thereover results in different conductivities in the different directions, for example parallel or cross-machine direction, but also at any angle to the machine direction.

If the full-surface polymeric conductive base layer is made, for example, by a corresponding depth-variable gravure cylinder, in different thickness, thereby angle-dependent conductivities are achieved.

Optionally, the polymeric conductive primer layer and the second polymeric conductive layer deposited thereover may also be separated by an insulator layer.

But there are also constructions of more than 2 each full-area and / or partial polymeric electrically conductive layers, which may possibly be separated by insulator layer (s) conceivable.

Preferably, the electrically conductive layer (s) of polymer (s) are not in direct contact with metallic layers and are separated therefrom by an insulator layer.

Furthermore, the electrically conductive polymer layers, as well as, if appropriate, the additional inorganic metallic and / or pigmented electrically conductive layers, can be coded as patches and thus also be applied in a machine-readable and / or structured manner. Furthermore, the electrically conductive polymer layers can subsequently be embossed inline or offline.

The carrier substrate may already have functional or decorative layers, or further layers may be applied after the conductive layer has been applied.

The carrier substrates may additionally have a lacquer layer, which may be unstructured or structured, for example embossed. The lacquer layer can be, for example, a release-capable transfer lacquer layer, it can be crosslinked or crosslinkable by radiation, for example UV radiation, and can be scratch-proof and / or antistatic. Both aqueous and solid coating systems, in particular lacquer systems based on polyester acrylate or epoxy acrylate, are rosin, acrylate, alkyd, melamine, PVA, PVC, isocyanate, urethane systems which are conventionally and / or reactively curing and / or can be radiation-curing.

As color or lacquer layers in each case a wide variety of compositions can be used. The composition of the individual layers may in particular vary according to their purpose, that is to say whether the individual layers serve exclusively for decorative purposes or should be a functional layer or whether the layer should be both a decoration layer and a functional layer.

These layers may be pigmented or unpigmented. As pigments, all known pigments such as titanium dioxide, zinc sulfide, kaolin, ITO, ATO, FTO, aluminum, chromium and silicon oxides and colored Pigments are used. In this case, solvent-based coating systems and systems without solvents can be used.

Suitable binders are various natural or synthetic binders.

For example, the functional layers may have certain magnetic, chemical, physical and also optical properties.

To adjust the magnetic properties, paramagnetic, diamagnetic and also ferromagnetic substances, such as iron, nickel and cobalt or their compounds or salts (for example oxides or sulfides) can be used.

Particularly suitable for use in conjunction with the electrically conductive polymer layers according to the invention are magnetic pigment paints with pigments based on Fe oxides, iron, nickel cobalt and their alloys, barium or cobalt ferrite, hard and soft magnetic iron and steel grades in aqueous or solvent-containing dispersions. Examples of suitable solvents are i-propanol, ethyl acetate, methyl ethyl ketone, methoxypropanol and mixtures thereof.

The pigments are preferably incorporated in acrylate polymer dispersions having a molecular weight of from 150,000 to 300,000, in nitrocellulose, acrylate-urethane dispersions, acrylate-styrene or PVC-containing dispersions or in solvent-containing dispersions of this type.

The optical properties of the layer can be visualized by visible dyes or pigments, luminescent dyes or pigments which fluoresce or phosphoresce in the visible, in the UV region or in the IR region, effect pigments, such as liquid crystals, pearlescent, bronzes and / or multilayers Color change pigments and heat-sensitive colors or pigments influence. These can be used in all possible combinations. In addition, phosphorescent pigments can also be used alone or in combination with other dyes and / or pigments.

Various properties can also be combined by adding various additives mentioned above. Thus, it is possible to use colored and / or conductive magnetic pigments. All mentioned conductive additives can be used.

Especially for the dyeing of magnetic pigments it is possible to use all known soluble and non-soluble dyes or pigments. For example, a brown magnetic paint can be metallic, e.g., by adding metals in its hue, e.g. be set silvery.

For printing soluble layers and also for applying partial conductive layers according to the invention, the ink or lacquer used can be soluble in a solvent, preferably in water, but it can also be a dye soluble in any solvent, for example in alcohol, esters and the like become. The color or the colored lacquer can be customary compositions based on natural or artificial macromolecules. The color may be pigmented or unpigmented. As pigments, all known pigments can be used. Particularly suitable are TiO ₂ , ZnS, kaolin and the like.

If a soluble color layer is used, it may optionally be removed after application of another layer in the process according to the invention by a suitable solvent adapted to the composition of the color layer in order to be able to produce codings in the form of characters and / or patterns of any possible type.

Subsequently, the color layer is removed by a suitable solvent, which is adapted to the composition of the color layer. Is preferred the paint is water-soluble. Optionally, the separation can be supported by mechanical action.

In order to further improve the dissolution of the covered ink layer, it is also possible to apply a thin highly pigmented ink layer and / or a pure pigment layer over the whole surface or register, the thickness of this layer being approximately 0.01-5 μm.

Furthermore, for example, insulator layers can be applied. As insulators, for example, organic substances and their derivatives and compounds, for example, paint and varnish systems, e.g. Epoxy, polyester, rosin, acrylate, alkyd, melamine, PVA, PVC, isocyanate, urethane systems which may be radiation-curable, for example by heat or UV radiation.

Such layers can be used in particular in the production of multilayer structures, for example for printed circuit boards, between two or more electrically conductive polymer layers and / or electrically conductive metallic and / or pigmented layers which have to be separated from one another.

These layers may be applied by known methods such as sputtering, sputtering, printing (e.g., gravure, flexo, screen, offset, digital printing, and the like), spraying, electroplating, and the like. The thickness of the functional layers is generally about 0.001 to 50 microns, preferably 0.1 to 20 microns.

Furthermore, partial or full-surface metallic layers may be present on the carrier substrate or subsequently applied.

This layer consists of a metal, a metal compound or an alloy, wherein these metallic layers can also represent inorganic electrically conductive layers. As the metal layer, layers of Al, Cu, Fe, Ag, Au, Cr, Ni, Zn and the like are suitable. As metal compounds For example, oxides or sulfides of metals, in particular TiO ₂ , Cr oxides, ZnS, ITO, ATO, FTO, ZnO, Al ₂ O ₃ or silicon oxides are suitable. Suitable alloys are, for example, Cu-Al alloys, Cu-Zn alloys and the like.

All of these layers can be applied over the entire area as well as partially, with registration and register accuracy, if appropriate also at least partially overlapping with the already existing layers.

If highly pigmented systems are applied by gravure printing, unwanted toning residues are formed on the film, in particular as a function of the doctor used. H. Thin layers outside the printing areas are applied to the film. Thereby, the adhesion of the subsequently applied layers can be deteriorated.

In order to avoid the formation of such Tonungsreste on the film, in addition to the optimization of doctor blade and cylindrical roughness and systems can be used, which already largely dry these thin layers on the cylinder surface and thus prevent transmission to the film.

Thus, for example, between the doctor blade and the pressure roller, a blow bar can be located, with a plurality of nozzles arranged over the entire width. Through these nozzles filtered air with defined humidity, optionally heated or cooled, directed at the same speed on the printing cylinder, whereby the thin layers dry on the cylinder and can not be applied to the carrier substrate. Instead of such a blow bar, an IR drying device situated over the entire width can also be used.

However, created Tonungsreste can also be removed for example by using a plasma (low pressure or Atmosphärenplasma-), Corona or flame process. By energetic plasma, For example, Ar or Ar / O ₂ plasma, the surface of Tonungsresten of the printing inks is cleaned.

In particular, when applying metallic layers, the optional additional use of such a process is advantageous.

At the same time, the surface is activated. In this case, terminal polar groups are generated on the surface. This improves the adhesion of metals and the like to the surface.

Optionally, simultaneously with the application of the plasma or corona or flame treatment, a thin metal or metal oxide layer can be applied as adhesion promoter, for example by sputtering or vapor deposition. Particularly suitable are Cr, Al, Ag, Ti, Cu, TiO ₂ , Si oxides or chromium oxides. This adhesion promoter layer generally has a thickness of 0.1 nm to 5 nm, preferably 0.2 nm to 2 nm, particularly preferably 0.2 to 1 nm.

As a result, the adhesion of a further partially or fully applied structured functional layer is further improved. This is a prerequisite for the production of functional layers with high precision and good adhesion.

The product is therefore optionally suitable for packaging as a security element in data carriers, in particular value documents such as identification cards, banknotes or labels, seals and the like, but also as packaging material, for example in the pharmaceutical and food industry, for example in the form of blister foils, cartons, covers, Foil packaging and the like suitable. Such products are also particularly suitable for applications in the electronics industry, for example as printed circuit boards, RF antennas for transponders and the like, displays, flexible circuits, medical devices, electrode assemblies, as heatable films, for example for windshields, as a transparent reflection layer under holograms and / or structured layers and the like. Further, because of their excellent optical properties, they can be used as a "high refractive index" layer, as decorative or optical elements, for example in architecture and the like. For use as security features, the substrates or film materials are preferably cut into strips and threads, wherein the width of the strips or threads may preferably be 0.05-10 mm.

Examples: Example 1 (not according to the invention):

On a carrier film of PET with a thickness of 50 microns, which is already partially coated with an optically active layer, and on a commercial adhesion promoter (A 1120, Fa. OSI)) is applied, from a storage vessel via a transfer roller, a dispersion of 2% Polyethylendioxythiophen (particle size 100 nm in the dispersion) with 2% polystyrene sulfonate in water / i-propanol as a dispersant over the entire surface in a layer thickness of 3 microns applied. Subsequently, the applied polymer layer is dried at 110 ° C.

The film thus produced has a conductivity of 800Ω / square, the conductive layer has a transparency of 87%

Example 2:

A mixture of ethylenedioxythiophene and Fe (III) toluenesulfonate as initiator in a weight ratio of 1:60 is then applied by gravure printing at 110 ° C. and polymerized. This mixture is polymerized in situ and is subsequently used to remove catalyst residues treated with water. Subsequently, the layer is dried and applied a conventional protective lacquer layer.

The conductive film thus produced has a conductivity of 220 Ω / square and the two conductive layers together have a transparency of 82%.

A subsequently applied to the film in a known manner fluorescent coating layer has no effect on the conductivity or transparency of the remaining free areas of the conductive layers.

Example 3:

Analogously to Example 1, a partial layer made from Baytron ^® M and Baytron ^® CB-40 in a weight ratio of 1: 60 was dissolved in n-butanol according to the in Fig. 1 and 5a described method applied to a 6 micron polyester film.

The partial layer has a line-shaped structure of 0.1 mm width at a distance of 0.1 mm.

On this layer, an opaque ink is applied partially in the form of any characters.

Subsequently, the substrate is cut into threads of a width of 1 mm, whereby an average of 5 line structures are present on a thread. The directional conductivity is 215 Ω / square.

Example 4:

The film produced according to Example 3 is coated with a 10 μm PET film having a 0.5 μm partial layer consisting of a magnetic printing ink based on Fe ₃ O ₄ in an acrylate polymer dispersion and a 0.2 μm layer of a fluorescent printing ink laminated by means of a commercially available laminating adhesive.

Subsequently, the surfaces were provided with a heat sealing lacquer.

The conductivity was 215 Ω / square, the magnetic properties were determined to be 330 nW / m with a coercivity of 250 Oerstedt.

Claims (8)

1. Method for producing safety elements comprising a carrier substrate onto which electrically conducting layers are applied, characterized in that the monomer ethylenedioxythiophene (EDT) is applied to the carrier substrate and is polymerized in situ using the initiator Fe(III) toluenesulphonate, wherein monomer and initiator are applied in a weight ratio of 1:20 to 1:100 and the monomer is applied with subsequent application of the initiator and/or catalyst or already in a mixture with the initiator and/or catalyst, wherein an electrically conducting layer of polyethylenedioxythiophene (PEDT) which is stabilized by the non-polymer-bound toluenesulphonate anion is produced.
2. Method according to Claim 1, characterized in that a catalyst is additionally used.
3. Method according to either of Claims 1 and 2, characterized in that initiator and/or catalyst residues and/or other unwanted reaction products are removed by washing with water treated by reverse osmosis, ion exchangers, distillation and/or physical treatment plants and having a defined content of alkali metal ions and/or alkaline earth metal ions.
4. Method according to any one of Claims 1 to 3, characterized in that the water used for washing is recirculated and treated by means of filtration, ion exchangers and/or distillation.
5. Method according to any one of Claims 3 to 4, characterized in that, according to requirements, fresh water treated by reverse osmosis, ion exchangers, distillation and/or physical treatment plants is fed to the wash water circuit.
6. Method according to any one of Claims 1 to 5, characterized in that a final wash step is carried out using fresh water treated by reverse osmosis, ion exchangers, distillation and/or physical treatment plants.
7. Method according to any one of Claims 1 to 6, characterized in that the wash operation is carried out in line or out of line.
8. Method according to any one of Claims 1 to 7, characterized in that functional and/or decorative layers are already present on the carrier substrate and/or are applied subsequently.

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