EP2050321A1 - Method for producing structured electrically conductive surfaces - Google Patents

Abstract

The invention relates to a method for producing structured, and/or the entire surface spanning, electrically conductive surfaces (3, 11) on an electrically nonconductive carrier 5 (1), wherein in a first step the surfaces (3) of a first level are applied to the carrier (1), in a second step the insulating layer (9) is applied at those positions, at which structured, and/or the entire surface spanning, electrically conductive surfaces (11) of a second level cross the structured, and/or the entire surface spanning, electrically conductive surfaces (3) of the first level, and no electrical contact is to occur between the structured, and/or the entire surface spanning, electrically conductive surfaces of the first level (3) and of the second level (11), in a third step the structured, and/or the entire surface spanning, electrically conductive surfaces (11) of the second level are applied according the first step, and the second and third steps are repeated, if necessary.

Description

 Process for producing structured, electrically conductive surfaces

The invention relates to a method for producing structured, electrically conductive surfaces on an electrically nonconductive support.

The method according to the invention is suitable, for example, for producing printed conductors on printed circuit boards, RFID antennas, transponder antennas or other antenna structures, chip card modules, flat cables, seat heaters, film conductors, printed conductors in solar cells or in LCD or plasma picture screens or galvanically coated products in any desired form. Also, the method is suitable for the production of decorative or functional surfaces on products that can be used to shield electromagnetic radiation, for heat conduction or as packaging.

In order to be able to realize complex circuits, it is often necessary to produce a plurality of conductor tracks one above the other with an insulation layer in between. On the one hand there is the possibility to provide several printed circuit boards, on each of which printed conductors are made, and to stack them one above the other, wherein each two printed circuit boards are separated from each other by an additional full-surface insulating layer. In order to be able to connect the individual printed conductors to one another, vias are provided in the printed circuit boards via which the printed conductors are contacted with one another. Alternatively, it is known, for example, from Hans-Joachim Hanke, module technology of electronics, hybrid carrier, pages 41 to 45, Verlag Technik Berlin, 1994, to provide on a circuit board several levels of tracks, which are each separated at the intersection by an insulating layer , With the currently known methods, a maximum of four conductor planes are possible in this way, in which the insulating layer is provided only in the region in which there is an underlying conductor track.

The production of such printed conductors is generally carried out, for example, by first applying a structured adhesive layer to the carrier body. At this structured adhesive layer, a metal foil or a metal powder is fixed. Alternatively, it is also known to apply a metal foil or a metal layer over the entire surface of a carrier body made of a plastic material and to press with the aid of a structured, heated stamp against the carrier body and fix it by its subsequent hardening th. The structuring of the metal layer takes place by mechanical removal of the regions of the metal foil or of the metal powder which are not connected to the adhesive layer or to the carrier body. Such a method is for example in DE-A 101 45 749 described. Disadvantage of this method is that after the application of a conductor layer, a large amount of material must be removed again. In addition, it is not possible with this method to apply an insulating layer.

Other disadvantages of the known from the prior art methods are the poor adhesion and the lack of homogeneity and patency of deposited by electroless and / or galvanic metallization metal layer. This is mostly due to the fact that the electrically conductive particles are embedded in a matrix material and therefore only a small part are exposed on the surface and thus only a small part of these particles is available for electroless and / or galvanic metallization. This is particularly problematic when using very small particles (particles in the micron to nanometer range). The formation of a homogeneous continuous metal coating is therefore very difficult or even impossible to realize, so that the process reliability is not given. By an existing O xidschicht on the electrically conductive particles, this effect is even enhanced.

Another disadvantage of the already known methods is the slow electroless and / or galvanic metallization. By embedding the electrically conductive particles in the matrix material, the number of particles exposed on the surface, which are available as growth nuclei for electroless and / or galvanic metallization, is low. This is u. a. also because the application of, for example, pressure dispersions, the heavy metal particles sink into the matrix material and thus remain only a few metal particles on the surface.

Another disadvantage of the already known methods, especially for the production of printed circuit boards, for example multilayer printed circuit boards, is the complex multi-layer structure. Due to the limited space (on a defined area only a certain number of traces and wirings feasible) and due to the PCB design must namely for the production of multilayer printed circuit boards always several inner layers, sometimes 18 pieces or more, and two outer layers, for example by lamination to be connected with each other. As a rule, an insulation layer must also be applied between two inner layers or between an inner and outer layer. In order to make contact, for example, with two conductor tracks on two different inner layers, these usually have to be connected to one another in a complex manner. For this purpose, these inner layers, for example, in the production of so-called buried vias or buried vias, for example, must be laboriously drilled and metallized. There are also electrical connections between the outer layers and an underlying inner layer, the so-called microVias, or small blind holes. These are intricately drilled mechanically or by means of laser beams, introduced photochemically or in the plasma etching process.

Another disadvantage of the methods described in the prior art is the large total thickness of printed circuit boards produced in this way.

The object of the present invention is to provide a method by means of which electrically conductive surfaces in a plurality of planes can be applied simply and cost-effectively to an electrically nonconductive support and which enables a higher interconnect density and the production of flat printed circuit boards.

The object is achieved by a method for the production of structured and / or full-area, electrically conductive surfaces on an electrically non-conductive carrier, which comprises the following steps:

a) applying the structured and / or full-area, electrically conductive surfaces of a first plane to the electrically non-conductive support,

b) applying an insulating layer at the positions at which structured and / or full-surface, electrically conductive surfaces of a second plane intersect the structured and / or full-surface, electrically conductive surfaces of the first plane and no electrical contact between the structured and / or full-surface, e electrically conductive surfaces of the first level and the second level,

c) applying the structured and / or full-surface, electrically conductive surfaces of the second level according to step a),

d) optionally repeating steps b) and c).

As a carrier to which the electrically conductive, structured or full-surface surface is applied, for example, rigid or flexible carrier are suitable. Preferably, the carrier is not electrically conductive. This means that the specific resistance is more than 10 ⁹ ohm x cm. Suitable carriers are, for example, reinforced or unreinforced polymers, as are commonly used for printed circuit boards. Suitable polymers are epoxy resins or modified epoxy resins, for example bifunctional or polyfunctional - A -

Ie bisphenol A or bisphenol F resins, epoxy novolac resins, brominated epoxy resins, aramid-reinforced or glass-fiber reinforced or paper-reinforced epoxy resins (for example FR4), glass fiber reinforced plastics, liquid cristal polymers (LCP), polyphenylene sulfides (PPS), polyoxymethylenes (POM) , Polyaryletherketones (PAEK), polyetheretherketones (PEEK), polyamides (PA), polycarbonates (PC), polybutylene terephthalates (PBT), polyethylene terephthalates (PET), polyimides (PI), polyimide resins, cyanate esters, bismaleimide-triazine resins, nylon, Vinyl ester resins, polyesters, polyester resins, polyamides, polyanilines, phenolic resins, polypyrroles, polyethylene naphthalate (PEN), polymethylmethacrylate, polyethylenedioxythiophenes, phenolic resin-coated aramid paper, polytetrafluoroethylene (PTFE), melamine resins, silicone resins, fluorine resins, allied polyphenylene ether (APPE), polyetherimides (PEI), polyphenylene oxides (PPO), polypropylenes (PP), polyethylenes (PE), polysulfones (PSU), polyethersulfones (PES), polyarylamines de (PAA), polyvinyl chlorides (PVC), polystyrenes (PS), acrylonitrile butadiene styrenes (ABS), acrylonitrile styrene acrylates (ASA), styrene acrylonitriles (SAN) and mixtures (blends) of two or more of the abovementioned polymers, which can be present in a wide variety of forms. The substrates may have additives known to the person skilled in the art, for example flame retardants.

In principle, all polymers listed below under the matrix material can also be used. Also suitable are other substrates which are likewise customary in the printed circuit board industry.

Furthermore, suitable substrates composites, foam-like polymers, polystyrene ^®, styrodur ^®, polyurethanes (PU), ceramic surfaces, textiles, paperboard, cardboard, paper, polymer coated paper, wood, mineral materials, silicon, glass, plant communities tissues and animal tissues.

The carrier can be both rigid and flexible.

The structured or full-surface, electrically conductive surface of the first level is applied, for example, by first applying a base layer with a dispersion containing electrically conductive particles and at least partially drying and / or hardening, then subsequently at least partially exposing the particles exposed and then provided by electroless and / or galvanic coating with a metal layer.

In a first step, the structured or full-surface base layer with a dispersion containing electrically conductive particles in a matrix material is applied to the support. wear. The electrically conductive particles may be particles of any desired geometry made of any electrically conductive material, mixtures of different electrically conductive materials or mixtures of electrically conductive and non-conductive materials. Suitable electrically conductive materials are, for example, carbon such as carbon black, graphite or carbon nanotubes, electrically conductive metal complexes, conductive organic compounds or conductive polymers or metals, preferably zinc, nickel, copper, tin, cobalt, manganese, iron, magnesium, lead, chromium , Bismuth, silver, gold, aluminum, titanium, palladium, platinum, tantalum and alloys thereof, or metal mixtures containing at least one of these metals. Examples of suitable alloys are CuZn, CuSn, CuNi, SnPb, SnBi, SnCo, NiPb, ZnFe, ZnNi, ZnCo and ZnMn. Particularly preferred are aluminum, iron, copper, nickel, zinc, tin, carbon and mixtures thereof.

Preferably, the electrically conductive particles have an average particle diameter of 0.001 to 100 .mu.m, preferably from 0.005 to 50 .mu.m and particularly preferably from 0.01 to 10 .mu.m. The average particle diameter can be determined by means of laser diffraction measurement, for example on a Microtrac X100 device. The distribution of the particle diameter depends on their production method. Typically, the diameter distribution has only one maximum, but several maxima are also possible.

The surface of the electrically conductive particle can be provided at least partially with a coating ("coating"). Suitable coatings may be inorganic (for example SiC> ₂ , phosphates) or organic in nature. Of course, the electrically conductive particle may also be coated with a metal or metal oxide. Also, the metal may be in partially oxidized form.

If two or more different metals are to form the electrically conductive particles, this can be done by mixing these metals. It is particularly preferred if the metals are selected from the group consisting of aluminum, iron, copper, nickel, zinc and tin.

However, the electrically conductive particles may also include a first metal and a second metal, the second metal being in the form of an alloy (with the first metal or one or more other metals), or the electrically conductive particles containing two different alloys.

In addition to the selection of the electrically conductive particles, the shape of the electrically conductive particles has an influence on the properties of the dispersion after a coating. in the Many variants known to those skilled in the art are possible with regard to the shape. The shape of the electrically conductive particles may be, for example, acicular, cylindrical, plate-shaped, tubular or spherical. These particle shapes represent idealized shapes, whereby the actual shape, for example as a result of the production, may deviate more or less strongly therefrom. For example, drop-shaped particles in the context of the present invention are a real deviation of the idealized spherical shape.

Electrically conductive particles having various particle shapes are commercially available.

If mixtures of electrically conductive particles are used, the individual mixing partners can also have different particle shapes and / or particle sizes. It is also possible to use mixtures of only one type of electrically conductive particles having different particle sizes and / or particle shapes. In the case of different particle shapes and / or particle sizes, the metals aluminum, iron, copper, nickel, zinc and tin as well as carbon are likewise preferred.

As already stated above, the electrically conductive particles in the form of their powders can be added to the dispersion. Such powders, for example metal powders, are common commercial products or can be easily prepared by known methods, such as by electrolytic deposition or chemical reduction from solutions of metal salts or by reduction of an oxidic powder, for example by hydrogen, by spraying or atomizing a molten metal, especially in cooling media , for example, gases or water. Preference is given to the gas and water atomization and the reduction of metal oxides. Metal powders of the preferred grain size can also be made by grinding coarser metal powders. For this purpose, for example, a ball mill is suitable.

In the case of iron, in addition to the gas and water atomization and the reduction of iron oxides, the carbonyl iron powder process for producing carbonyl iron powder is preferred. This is done by thermal decomposition of iron pentacarbonyl. This is described, for example, in Ullman's Encyclopedia of Industrial Chemistry, 5th Edition, Vol. A14, page 599. The decomposition of the iron pentacarbonyl can be carried out, for example, at elevated temperatures and elevated pressures in a heatable decomposer comprising a tube made of a refractory material such as quartz glass or V2A steel in a preferably vertical position, that of a heating device, for example comprising heating baths, heating wires or from a heating medium through which flows through a heating jacket. Platelet-shaped electrically conductive particles can be controlled by optimized conditions in the production process or subsequently obtained by mechanical treatment, for example by treatment in a stirred ball mill.

Based on the total weight of the dried coating, the proportion of electrically conductive particles in the range of 20 to 98 wt .-%. A preferred range of the proportion of the electrically conductive particles is from 30 to 95% by weight, based on the total weight of the dried coating.

Suitable matrix materials are, for example, binders with pigment-affine anchoring group, natural and synthetic polymers and their derivatives, natural resins and synthetic resins and their derivatives, natural rubber, synthetic rubber, proteins, cellulose derivatives, drying and non-drying oils and the like. These can, but do not have to be, chemically or physically curing, for example air-hardening, radiation-curing or temperature-curing.

Preferably, the matrix material is a polymer or polymer mixture.

Preferred polymers as the matrix material are ABS (acrylonitrile-butadiene-styrene); ASA (acrylonitrile-styrene-acrylate); acrylated acrylates; alkyd resins; Alkylvinylacetate; Alkylene vinyl acetate copolymers, especially methylene vinyl acetate, ethylene vinyl acetate, butylene vinyl acetate; Alkylenvinylchlorid copolymers; amino resins; Aldehyde and ketone resins; Cellulose and cellulose derivatives, in particular hydroxyalkylcellulose, cellulose esters, such as acetates, propionates, butyrates, carboxyalkylcelluloses, cellulose nitrate; epoxy acrylates; epoxy resins; modified epoxy resins, for example bifunctional or polyfunctional bisphenol A or bisphenol F resins, epoxy novolac resins, brominated epoxy resins, cycloaliphatic epoxy resins; aliphatic epoxy resins, glycidyl ethers, vinyl ethers, ethylene-acrylic acid copolymers; Hydrocarbon resins; MABS (transparent ABS with acrylate units included); Melamine resins, maleic anhydride copolymers; methacrylates; Natural rubber; synthetic rubber; Chlorinated rubber; Natural resins; rosins; Shellac; Phenol resins; Polyester; Polyester resins, such as phenylester resins; polysulfones; Polyether sulphones; polyamides; polyimides; polyanilines; polypyrroles; Polybutylene terephthalate (PBT); Polycarbonate (for example Makrolon ^® from Bayer AG); polyester; polyether; polyethylene; Polyethylenthiophene; polyethylene naphthalates; Polyethylene terephthalate (PET); Polyethylene terephthalate glycol (PETG); polypropylene; Polymethyl methacrylate (PMMA); Polyphenylene oxide (PPO); Polystyrenes (PS), polytetrafluoroethylene (PTFE); polytetrahydrofuran ran; Polyethers (for example polyethylene glycol, polypropylene glycol), polyvinyl compounds, in particular polyvinyl chloride (PVC), PVC copolymers, PVdC, polyvinyl acetate and copolymers thereof, optionally partially hydrolyzed polyvinyl alcohol, polyvinyl acetals, polyvinyl acetates, polyvinyl pyrrolidone, polyvinyl ethers, polyvinyl acrylates and methacrylates in solution and as Dispersion and its copolymers, polyacrylic acid esters and polystyrene copolymers; Polystyrene (impact or not impact modified); Polyurethanes, non-crosslinked or crosslinked with isocyanates; polyurethane acrylates; Styrene-acrylic copolymers; Styrene-butadiene block copolymers (for example, Styroflex ^® or Styrolux ^® from BASF AG, K-Resin ™ CPC); Proteins, such as casein; SIS; Triazine resin, bismaleimide-triazine resin (BT), cyanate ester resin (CE), allied polyphenylene ether (APPE). Furthermore, mixtures of two or more polymers can form the matrix material.

Particularly preferred polymers as matrix material are acrylates, acrylate resins, cellulose derivatives, methacrylates, methacrylate resins, melamine and amino resins, polyalkylenes, polyimides, epoxy resins, modified epoxy resins, for example bifunctional or polyfunctional bisphenol A or bisphenol F resins, epoxy novolaks. Resins, brominated epoxy resins, cycloaliphatic epoxy resins; aliphatic epoxy resins, glycidyl ethers, vinyl ethers, and phenolic resins, polyurethanes, polyesters, polyvinyl acetals, polyvinyl acetates, polystyrenes, polystyrene copolymers, polystyrene acrylates, styrene-butadiene block copolymers, alkylene vinyl acetate and vinyl chloride copolymers, polyamides and their copolymers.

In the production of printed circuit boards, the matrix material for the dispersion is preferably thermally or radiation-curing resins, for example modified epoxy resins, such as bifunctional or polyfunctional bisphenol A or bisphenol F resins, epoxy novolac resins, brominated epoxy resins, cycloaliphatic epoxy resins; aliphatic epoxy resins, glycidyl ethers, cyanate esters, vinyl ethers, phenolic resins, polyimides, melamine resins and amino resins, polyurethanes, polyesters and cellulose derivatives.

Based on the total weight of the dry coating, the proportion of the organic binder component is from 0.01 to 60% by weight. Preferably, the proportion is 0.1 to 45 wt .-%, more preferably 0.5 to 35 wt .-%.

In order to be able to apply the dispersion containing the electrically conductive particles and the matrix material to the support, the dispersion may furthermore be admixed with a solvent or a solvent mixture in order to adjust the viscosity of the dispersion which is suitable for the respective application method. Suitable solvents are, for example, aliphatic and aromatic hydrocarbons (for example n-octane, cyclohexane, toluene, XyIoI), alcohols (for example, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, amyl alcohol), polyhydric alcohols such as glycerol, ethylene glycol, propylene glycol, neopentyl glycol, alkyl esters (for example, methyl acetate, ethyl acetate, propyl acetate , Butyl acetate, isobutyl acetate, isopropyl acetate, 3-methylbutanol), alkoxy alcohols (for example methoxypropanol, methoxybutanol, ethoxypropanol), alkylbenzenes (for example ethylbenzene, isopropylbenzene), butylglycol, butyldiglycol, alkylglycolacetates (for example butylglycol acetate, butyldiglycol acetate) , Diacetone alcohol, diglycol dialkyl ethers, diglycol monoalkyl ethers, dipropylene glycol dialkyl ethers, dipropylene glycol monoalkyl ethers, diglycol alkyl ether acetates, dipropylene glycol alkyl ether acetates, dioxane, dipropylene glycol and ethers, diethylene glycol and ethers, DBE (dibasic esters), ethers (for example diethyl ether, tetrahydrofuran), ethylene chloride, Ethylene glycol, ethylene glycol acetate, ethylene glycol dimethyl ester, cresol, lactones (eg for example, butyrolactone), ketones (for example, acetone, 2-butanone, cyclohexanone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK)), methyl diglycol, methylene chloride, methylene glycol, methyl glycol acetate, methylphenol (ortho-, meta-, para-cresol), pyrrolidones (For example, N-methyl-2-pyrrolidone), propylene glycol, propylene carbonate, carbon tetrachloride, toluene, trimethylolpropane (TMP), aromatic hydrocarbons and mixtures, aliphatic hydrocarbons and mixtures, alcoholic monoterpenes (such as terpineol), water and mixtures of two or several of these solvents.

Preferred solvents are alcohols (for example ethanol, 1-propanol, 2-propanol, butanol), alkoxyalcohols (for example methoxypropanol, ethoxypropanol, butylglycol, butyldiglycol), butyrolactone, diglycol dialkyl ethers, diglycol monoalkyl ethers, dipropylene glycol dialkyl ethers, dipropylene glycol monoalkyl ethers, esters (for example ethyl acetate , Butyl acetate, butyl glycol acetate, butyl diglycol acetate, diglycol alkyl ether acetates, dipropylene glycol alkyl ethers, DBE), ethers (for example tetrahydrofuran), polyhydric alcohols such as glycerol, ethylene glycol, propylene glycol, neopentyl glycol, ketones (for example acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone), hydrocarbons (for Example cyclohexane, ethylbenzene, toluene, xylene), N-methyl-2-pyrrolidone, water and mixtures thereof.

When the dispersion is applied to the support by an inkjet method, alkoxy alcohols (for example ethoxypropanol, butylglycol, butyldiglycol) and polyhydric alcohols, such as glycerol, esters (for example butyldiglycol acetate, butylglycol acetate, dipropylene glycol methyl ether acetates), water, cyclohexanone, butyrolactone, N-methyl-pyrrolidone, DBE and mixtures thereof as solvent are particularly preferred. In the case of liquid matrix materials (for example liquid epoxy resins, acrylate esters), the respective viscosity can alternatively also be adjusted via the temperature during application, or via a combination of solvent and temperature. The dispersion may further contain a dispersant component. This consists of one or more dispersants.

In principle, all dispersants known to the person skilled in the art for use in dispersions and described in the prior art are suitable. Preferred dispersants are surfactants or surfactant mixtures, for example anionic, cationic, amphoteric or nonionic surfactants.

Cationic and anionic surfactants are described, for example, in "Encyclopedia of Polymer Science and Technology", J. Wiley & Sons (1966), Vol. 5, pp. 816-818, and in "Emulsion Polymerization and Emulsion Polymers", editors P. Lovell and M. El-Asser, published by Wiley & Sons (1997), pages 224-226.

Examples of anionic surfactants are alkali metal salts of organic carboxylic acids having chain lengths of 8 to 30 carbon atoms, preferably 12 to 18 carbon atoms. These are in the

Generally referred to as soaps. Usually they are called sodium, potassium or

Ammonium salts used. In addition, alkyl sulfates and alkyl or alkylaryl sulfonates having 8 to 30 carbon atoms, preferably 12 to 18 carbon atoms, can be used as anionic surfactants. Particularly suitable compounds are alkali dodecyl sulfates, for example sodium dodecyl sulfate or potassium dodecyl sulfate, and alkali metal salts of C ₂ -C ₆ -

Paraffin sulfonic acids. Furthermore, sodium dodecylbenzenesulfonate and sodium dioctylsulfonosuccinate are suitable.

Examples of suitable cationic surfactants are salts of amines or diamines, quaternary ammonium salts, such as hexadecyltrimethylammonium bromide, and salts of long chain substituted cyclic amines, such as pyridine, morpholine, piperidine. In particular, quaternary ammonium salts, such as hexadecyltrimethylammonium bromide, are used by trialkylamines. The alkyl radicals preferably have 1 to 20 carbon atoms therein.

In particular, according to the invention, nonionic surfactants can be used as the dispersant component. Nonionic surfactants are described, for example, in CD Römpp Chemie Lexikon - Version 1.0, Stuttgart / New York: Georg Thieme Verlag 1995, keyword "nonionic surfactants".

Suitable nonionic surfactants are, for example, polyethylene oxide or polypropylene oxide-based substances, such as Pluronic® or Tetronic® from BASF Aktiengesellschaft. Polyalkylene glycols suitable as nonionic surfactants generally have a number average molecular weight M _n in the range from 1000 to 15000 g / mol, preferably 2000 to 13000 g / mol, particularly preferably 4000 to 1000 g / mol. Preferred nonionic surfactants are polyethylene glycols.

The polyalkylene glycols are known per se or can be prepared by processes known per se, for example by anionic polymerization with alkali hydroxides, such as sodium or potassium hydroxide, or alkali metal alkoxides, such as sodium, sodium or potassium or potassium isopropoxide, as catalysts and with the addition of at least one starter molecule, the 2 to 8, preferably 2 to 6, containing bonded reactive hydrogen atoms, or by cationic polymerization with Lewis acids, such as antimony pentachloride, boron fluoride etherate or bleaching earth, as catalysts of one or more alkylene with 2 to 4 carbon atoms in the alkylene radical ,

Suitable alkylene oxides are, for example, tetrahydrofuran, 1, 2 or 2,3-butylene oxide, styrene oxide and preferably ethylene oxide and / or 1, 2-propylene oxide. The alkylene oxides can be used individually, alternately in succession or as mixtures. Suitable starter molecules are, for example: water, organic dicarboxylic acids, such as succinic acid, adipic acid, phthalic acid or terephthalic acid, aliphatic or aromatic, optionally N-mono-, N, N- or N, N'-dialkyl-substituted diamines having 1 to 4 carbon atoms in the alkyl radical, such as optionally mono- and dialkyl-substituted ethylenediamine, diethylenetriamine, triethylenetetramine, 1, 3-propylenediamine, 1, 3 or 1, 4-butylenediamine, 1, 2, 1, 3, 1, 4- , 1, 5 or 1,6-hexamethylenediamine.

Also suitable as starter molecules are: alkanolamines, for example ethanolamine, N-methyl- and N-ethylethanolamine, dialkanolamines, for example diethanolamine, N-methyl- and N-ethyldiethanolamine, and trialkanolamines, for example triethanolamine, and ammonia. Preference is given to using polyhydric, in particular dihydric, trihydric or higher alcohols, such as ethanediol, propanediol 1, 2 and 1, 3, diethylene glycol, dipropylene glycol, butanediol 1, 4, hexanediol 1, 6, glycerol, trimethylolpropane, pentaerythritol, and sucrose, sorbitol and sorbitol.

Also suitable for the dispersant component are esterified polyalkylene glycols, for example the mono-, di-, tri- or polyesters of the polyalkylene glycols mentioned, which are obtained by reaction of the terminal OH groups of said polyalkylene glycols with organic acids, preferably adipic acid or terephthalic acid, in per se can be produced in a known manner. Nonionic surfactants are substances produced by alkoxylation of compounds with active hydrogen atoms, for example addition products of alkylene oxide onto fatty alcohols, oxo alcohols or alkylphenols. Thus, for example, ethylene oxide or 1,2-propylene oxide can be used for the alkoxylation.

Further possible nonionic surfactants are alkoxylated or non-alkoxylated sugar esters or sugar ethers.

Sugar ethers are alkylglycosides obtained by reaction of fatty alcohols with sugars. Sugar esters are obtained by reacting sugars with fatty acids. The sugar, fatty alcohols and fatty acids necessary for the preparation of the substances mentioned are known to the person skilled in the art.

Suitable sugars are described for example in Beyer / Walter, textbook of organic chemistry, S. Hirzel Verlag Stuttgart, 19th edition, 1981, pages 392 to 425. Possible sugars are D-sorbitol and the sorbitan obtained by dehydration of D-sorbitol.

Suitable fatty acids are saturated or mono- or polyunsaturated unbranched or branched carboxylic acids having 6 to 26, preferably 8 to 22, particularly preferably 10 to 20 C atoms, as described, for example, in CD Römpp Chemie Lexikon, Version 1.0, Stuttgart / New York: Georg Thieme Verlag 1995, keyword "fatty acids" are called. Conceivable are fatty acids, such as lauric acid, palmitic acid, stearic acid and oleic acid.

Suitable fatty alcohols have the same carbon skeleton as the compounds described as suitable fatty acids.

Sugar ethers, sugar esters and the processes for their preparation are known in the art. Preferred sugar ethers are prepared by known processes by reacting the said sugars with the stated fatty alcohols. Preferred sugar esters are prepared by known processes by reacting the said sugars with said fatty acids. Suitable sugar esters are mono-, di- and triesters of sorbitans with fatty acids, in particular sorbitan monolaurate, sorbitan dilaurate, sorbitan trilaurate, sorbitan monooleate, sorbitan dioleate, sorbitan trioleate, sorbitan monopalmitate, sorbitan palmitate, sorbitan tripalmitate, sorbitan monostearate, sorbitan distearate, sorbitan tristearate and sorbitan sesquioleate, a mixture of sorbitan mono - and diesters of oleic acid. Possible dispersants are thus alkoxylated sugar ethers and sugar esters, which are obtained by alkoxylation of said sugar ethers and sugar esters. Preferred alkoxylating agents are ethylene oxide and 1,2-propylene oxide. The degree of alkoxylation is generally between 1 and 20, preferably 2 and 10, more preferably 2 and 6. Examples of these are polysorbates which are obtained by ethoxylation of the sorbitan esters described above, for example described in CD Römpp Chemie Lexikon - Version 1.0, Stuttgart / New York: Georg Thieme Verlag 1995, keyword "Polysorbate". Suitable polysorbates are polyethoxysorbitan, stearate, palmitate, tri-stearate, oleate, trioleate, in particular polyethoxysorbitan, which is available for example as Tween ^® 60, the ICI Amer- rica Inc. (described for example in CD Römpp Chemie Lexikon - Version 1.0 , Stuttgart / New York: Georg Thieme Verlag 1995, keyword "Tween ^® ").

The use of polymers as dispersants is also possible.

The dispersant may be used in the range of 0.01 to 50% by weight based on the total weight of the dispersion. The proportion is preferably 0.1 to 25% by weight, more preferably 0.2 to 10% by weight.

Furthermore, the dispersion of the invention may contain a filler component. This can consist of one or more fillers. Thus, the filler component of the metallizable composition may contain fibrous, layered or particulate fillers or mixtures thereof. These are preferably commercially available products, such as carbon and mineral fillers.

Furthermore, fillers or reinforcing materials such as glass powder, mineral fibers, whiskers, aluminum hydroxide, metal oxides such as aluminum oxide or iron oxide, mica, quartz powder, calcium carbonate, barium sulfate, titanium dioxide or wollastonite can be used.

Furthermore, further additives, such as thixotropic agents, for example silicic acid, silicates, such as aerosils or bentonites, or organic thixotropic agents and thickeners, such as polyacrylic acid, polyurethanes, hydrogenated castor oil, dyes, fatty acids, fatty acid amides, plasticizers, wetting agents, defoamers, lubricants , Driers, crosslinkers, photoinitiators, complexing agents, waxes, pigments, conductive polymer particles, can be used. The proportion of the filler component based on the total weight of the dry coating is preferably 0.01 to 50 wt .-%. Further preferred are 0.1 to 30 wt .-%, particularly preferably 0.3 to 20 wt .-%.

Furthermore, processing aids and stabilizers such as UV stabilizers, lubricants, corrosion inhibitors and flame retardants can be present in the dispersion according to the invention. Usually, their proportion based on the total weight of the dispersion 0.01 to 5 wt .-%. Preferably, the proportion is 0.05 to 3 wt .-%.

After the application of the structured or full-surface base layer to the carrier with the dispersion containing the electrically conductive particles in the matrix material and the drying or hardening of the matrix material, the particles are for the most part within the matrix, so that no continuous electrically conductive Surface was created. To produce the continuous electrically conductive surface, it is necessary to coat the structured or full-surface base layer applied to the carrier with an electrically conductive material. This coating is generally carried out by electroless and / or galvanic metallization.

In order to be able to electrolessly and / or electrolytically coat the structured or full-surface base layer, it is first necessary to at least partially dry or cure the structured or full-surface base layer applied with the dispersion. The drying or hardening of the structured or full-surface surface is carried out by conventional methods. For example, the matrix material can be cured chemically, for example by polymerization, polyaddition or polycondensation of the matrix material, for example by UV radiation, electron radiation, microwave radiation, IR radiation or temperature, or by purely physical means by evaporation of the solvent are dried. A combination of drying by physical and chemical means is possible. After at least partial drying or curing, the electrically conductive particles contained in the dispersion are at least partially exposed according to the invention in order to obtain already electrically conductive nuclei at which the metal ions can be deposited to form a metal layer during the subsequent electroless and / or galvanic metallization. If the particles consist of materials which oxidize easily, it may additionally be necessary to at least partially remove the oxide layer beforehand. Depending on the implementation of the method, for example, when using acidic electrolyte solutions, the removal of the oxide layer can be take place simultaneously with the onset of metallization, without an additional process step is required.

One advantage that particles have to release before electroless and / or galvanic metallization is that the exposure of the particles must result in an approximately 5 to 10% by weight reduction in the amount of electrically conductive particles in the coating in order to form a continuous one get electrically conductive surface, as is the case when the particles are not exposed. Further advantages are the homogeneity and consistency of the coatings produced and the high process reliability.

The exposure of the electrically conductive particles can be done either mechanically, for example by brushing, grinding, milling, sandblasting or irradiation with supercritical carbon dioxide, physically, for example by heating, laser, UV light, corona or plasma discharge, or chemically. In the case of a chemical exposure, it is preferable to use a chemical or chemical mixture suitable for the matrix material. In the case of a chemical exposure, either the matrix material can be at least partially dissolved and washed down by a solvent on the surface, or the chemical structure of the matrix material can be at least partially destroyed by means of suitable reagents, whereby the electrically conductive particles are exposed. Reagents that swell the matrix material are also suitable for exposing the electrically conductive particles. The swelling results in cavities into which the metal ions to be deposited can penetrate from the electrolyte solution, whereby a larger number of electrically conductive particles can be metallized. The adhesion, the homogeneity and the uniformity of the subsequently electrolessly and / or electrodeposited metal layer are significantly better than in the processes described in the prior art. Due to the higher number of exposed electrically conductive particles, the process speed in the metallization is also significantly higher, whereby additional cost advantages can be achieved.

For example, when the matrix material is an epoxy resin, a modified epoxy resin, an epoxy novolac, a polyacrylic acid ester, ABS, a styrene-butadiene copolymer or a polyether, the exposure of the electroconductive particles is preferably carried out with an oxidizing agent. The oxidizing agent breaks up bonds in the matrix material, which allows the binder to be peeled off and thereby expose the particles. Suitable oxidizing agents are, for example, manganates, for example potassium permanganate, potassium manganate, sodium permanganate, sodium manganate, Hydrogen peroxide, oxygen, oxygen in the presence of catalysts such as manganese, molybdenum, bismuth, tungsten and cobalt salts, ozone, vanadium pentoxide, selenium dioxide, ammonium polysulfide solution, sulfur in the presence of ammonia or amines, manganese dioxide, potassium ferrate, dichromate / Sulfuric acid, chromic acid in sulfuric acid or in acetic acid or in acetic anhydride, nitric acid, hydrochloric acid, hydrobromic acid, pyridinium dichromate, chromic acid-pyridine complex, chromic anhydride, chromium (VI) oxide, periodic acid, lead tetraacetate, quinone, methylquinone, anthraquinone, bromine, Chlorine, fluorine, iron (III) salt solutions, disulphate solutions, sodium percarbonate, salts of oxohalogenic acids, such as, for example, chlorates or bromates or iodates, salts of haloperuric acids, for example sodium periodate or sodium perchlorate, sodium perborate, dichromates, such as, for example Sodium dichromate, salts of persulfuric acid, such as potassium peroxodisulfate, potassium peroxomonosu lfate, pyridinium chlorochromate, salts of hypohalogenic acids, for example sodium hypochlorite, dimethyl sulfoxide in the presence of electrophilic reagents, tert-butyl hydroperoxide, 3-chlorobenzene benzoic acid, 2,2-dimethylpropanal, des-Martin periodinane, oxalyl chloride, urea-hydrogen peroxide adduct , Urea peroxide, 2-iodoxybenzoic acid, potassium peroxomonosulfate, m-chloroperbenzoic acid, N-methylmorpholine N-oxide, 2-methylprop-2-yl hydroperoxide, peracetic acid, pivaldehyde, osmium tetraoxide, oxones, ruthenium (III) and (IV) salts , Oxygen in the presence of 2,2,6,6-tetramethylpiperidinyl-N-oxide, triacetoxiperiodinane, trifluoroacetic acid, trimethylacetaldehyde, ammonium nitrate. Optionally, to improve the exposure process, the temperature may be increased during the process.

Preference is given to manganates, for example potassium permanganate, potassium manganate, sodium permanganate, sodium manganate; Hydrogen peroxide, N-methylmorpholine N-oxide, percarbonates, for example sodium or potassium percarbonate, perborates, for example sodium or potassium perborate; Persulfates, for example sodium or potassium persulfate; Sodium, potassium and ammonium peroxodis and monosulphates, sodium hypochlorite, urea-hydrogen peroxide adducts, salts of oxohalogenic acids, such as chlorates or bromates or iodates, salts of halogenated acids, such as sodium periodate or sodium perchlorate, tetrabutylammonium peroxydisulfate, quinones, iron (III) salt solutions, vanadium pentoxide, pyridinium dichromate, hydrochloric acid, bromine, chlorine, dichromate.

Particularly preferred are potassium permanganate, potassium manganate, sodium permanganate, sodium manganate, hydrogen peroxide and its adducts, perborates, percarbonates, persulfates, peroxodisulfates, sodium hypochlorite and perchlorates. In order to expose the electrically conductive particles in a matrix material containing, for example, ester structures, such as polyester resins, polyester acrylates, polyether acrylates, polyester urethanes, it is preferred to use, for example, acidic or alkaline chemicals and / or chemical mixtures. Preferred acidic chemicals and / or chemical mixtures are, for example, concentrated or dilute acids, such as hydrochloric acid, sulfuric acid, phosphoric acid or nitric acid. Also, organic acids, such as formic acid or acetic acid, may - depending on the matrix material - be suitable. Suitable alkaline chemicals and / or chemical mixtures are, for example, bases, such as sodium hydroxide solution, potassium hydroxide solution, ammonium hydroxide or carbonates, for example sodium carbonate or potassium carbonate. Optionally, to improve the exposure process, the temperature may be increased during the process.

Solvents can also be used to expose the electrically conductive particles in the matrix material. The solvent must be matched to the matrix material as the matrix material must dissolve in the solvent or swell through the solvent. If a solvent is used in which the matrix material dissolves, the base layer is only brought into contact with the solvent for a short time, so that the upper layer of the matrix material is dissolved and thereby becomes detached. In principle, all abovementioned solvents can be used. Preferred solvents are xylene, toluene, halogenated hydrocarbons, acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), diethylene glycol monobutyl ether. Optionally, to improve the dissolution behavior, the temperature during the dissolution process can be increased.

Furthermore, it is also possible to expose the electrically conductive particles by a mechanical method. Suitable mechanical methods include, for example, brushing, grinding, abrasive polishing, or jet blasting, blasting, or supercritical carbon dioxide blasting. By such a mechanical process, in each case the uppermost layer of the cured printed structured base layer is removed. As a result, the electrically conductive particles contained in the matrix material are exposed.

As abrasives for polishing, it is possible to use all abrasives known to the person skilled in the art. A suitable abrasive is, for example, pumice. In order to remove the uppermost layer of the cured dispersion by the pressure jet with the water jet, the water jet preferably contains small solid particles, for example pumice flour (Al ₂ O ₃ ) having an average particle size distribution of 40 to 120 μm, preferably 60 to 80 μm, or quartz flour (SiO ₂ ) with a particle size> 3 μm. If the electrically conductive particles contain a material which can easily oxidize, in a preferred variant of the method, before the formation of the metal layer on the structured or full-surface base layer, the oxide layer is at least partially removed. The removal of the oxide layer can take place, for example, chemically and / or mechanically. Suitable substances with which the base layer can be treated to chemically remove an oxide layer from the electrically conductive particles are, for example, acids such as concentrated or dilute sulfuric acid or concentrated or dilute hydrochloric acid, citric acid, phosphoric acid, sulfamic acid, formic acid, acetic acid.

Suitable mechanical methods for removing the oxide layer from the electrically conductive particles are generally the same as the mechanical methods of exposing the particles.

In order that the dispersion which is applied to the support adheres firmly to the support, in a preferred embodiment it is cleaned before the application of the structured or full-surface base layer by a dry process, a wet-chemical process and / or a mechanical process. In particular, it is also possible by means of the wet-chemical and the mechanical method to roughen the surface of the carrier so that the dispersion adheres better to it. As a wet-chemical method is particularly suitable rinsing the carrier with acidic or alkaline reagents or with suitable solvents. Also water in conjunction with ultrasound can be used. Suitable acidic or alkaline reagents are, for example, hydrochloric acid, sulfuric acid or nitric acid, phosphoric acid or sodium hydroxide solution, caustic lye or carbonates, such as potassium carbonate. Suitable solvents are the same as they may be included in the dispersion for applying the base layer. Preferred solvents are alcohols, ketones and hydrocarbons, which are to be selected depending on the carrier material. Also, the oxidizing agents that have already been mentioned in the activation, can be used. Mechanical methods of cleaning the substrate prior to applying the patterned or full-surface base layer are generally the same as they can be used to expose the electrically conductive particles and remove the oxide layer of the particles.

To remove dust and other particles that may affect the adhesion of the dispersion on the support, as well as for roughening the surface are particularly dry cleaning methods. These are, for example, dedusting by means of brushes and / or deionized air, corona discharge or low-pressure plasma and the particle removal by means of rollers and / or rollers, which are provided with an adhesive layer.

By corona discharge and low-pressure plasma, the surface tension of the substrate is selectably increased, the substrate surface is cleaned of organic residues and thus improves both the wetting with the dispersion and the adhesion of the dispersion.

Preferably, the structured and / or full-surface base layer is printed with the dispersion by any printing process on the support. The printing method by which the base layer is printed is, for example, a roll or sheet printing method such as screen printing, gravure printing, flexographic printing, letterpress printing, pad printing, ink jet printing, the Lasersonic method ^® as described in DE10051850 or offset printing. However, any further printing method known to the person skilled in the art can also be used. It is also possible to apply the surface by another common and well-known coating method. Such coating methods are, for example, casting, brushing, knife coating, brushing, spraying, dipping, rolling, powdering, fluidized bed or the like. The layer thickness of the structured or full surface area produced by the printing or the coating method preferably varies between 0.01 and 50 μm, more preferably between 0.05 and 25 μm and particularly preferably between 0.1 and 15 μm. The layers can be applied both over the entire surface as well as structured.

Depending on the printing process, different fine structures can be imprinted.

Preferably, the dispersion is stirred or pumped in a storage container prior to application to the carrier. By stirring and / or pumping a possible sedimentation of the particles contained in the dispersion is prevented. Furthermore, it is also advantageous if the dispersion is heated in the reservoir. This makes it possible to achieve an improved printed image of the base layer on the carrier, since a constant viscosity can be set by the tempering. The temperature control is particularly necessary when the dispersion is heated, for example, by the stirring and / or pumping due to the energy input of the stirrer or the pump and thereby changes the viscosity thereof.

To increase the flexibility and cost reasons, digital printing processes, for example inkjet printing, LaserSonic®, are particularly suitable in the case of a print application. These processes generally eliminate the cost of producing stencils, such as printing rolls or screens, as well as their constant change when several different structures need to be printed one behind the other. With digital printing, you can immediately switch to a new design without the need for retooling or downtime.

In the case of application of the dispersion by means of the inkjet method, preference is given to using electrically conductive particles having a maximum size of 15 μm, particularly preferably 10 μm, in order to prevent clogging of the inkjet nozzles. To avoid sedimentation in the inkjet head, the dispersion can be pumped by means of a pumped circulation, so that the particles do not settle. Furthermore, it is advantageous if the system can be heated to adjust the viscosity of the dispersion verdruckbar.

In addition to the one-sided application of the dispersion to the carrier, it is also possible with the method according to the invention to provide the carrier with an electrically conductive structured or full-surface base layer on its top and bottom sides. With the aid of plated-through holes, the structured or full-surface electrically conductive base layers on the top side and the underside of the carrier can be electrically connected to one another. For the via, for example, a wall of a bore in the carrier is provided with an electrically conductive surface. In order to produce the through-connection, it is possible, for example, to form bores in the support, on the wall of which the dispersion which contains the electrically conductive particles is applied during the printing of the structured or full-surface base layer. In a sufficiently thin carrier, it is not necessary to coat the wall of the bore with the dispersion, as in the electroless and / or electroplating with a sufficiently long coating time also within the hole forms a metal layer by the top and Grow together underside of the carrier into the bore growing metal layers, whereby the electrical connection of the electrically conductive structured or full-surface surfaces of the top and bottom of the carrier is formed. In addition to the method according to the invention, it is also possible to use other methods known from the prior art for metallizing bores and / or blind holes.

In order to obtain a mechanically stable structured or full-surface base layer on the support, it is preferred that the dispersion with which the structured or full-surface

Base layer is applied to the carrier, at least partially hardens after application. Depending on the matrix material curing takes place as described above for example by the action of heat, light (UVA / is) and / or radiation, for example infrared radiation, electron radiation, gamma radiation, X-radiation, microwaves. To trigger the curing reaction, if necessary, a suitable activator must be added. Curing can also be achieved by combining various processes, for example by combining UV radiation and heat. The combination of the curing processes can be carried out simultaneously or sequentially. Thus, for example, UV radiation can initially only harden the layer so that the formed structures no longer flow apart. Thereafter, the layer can be cured by exposure to heat. The action of heat can take place directly after the UV curing and / or after the galvanic metallization. After at least partial curing - as already described above - in a preferred variant, the electrically conductive particles are at least partially exposed. In order to produce the continuous electrically conductive surface, after exposing the electrically conductive particles, at least one metal layer is formed on the structured or full-surface base layer by electroless and / or galvanic coating. The coating can be carried out by any method known to those skilled in the art. Also, any conventional metal coating can be applied by the method of coating. The composition of the electrolyte solution used for the coating depends on which metal the electrically conductive structures are to be coated on the substrate. In principle, all metals which are nobler or equally noble as the most noble metal of the dispersion can be used for electroless and / or electroplating. Typical metals which are deposited by electroplating on electrically conductive surfaces are, for example, gold, nickel, palladium, platinum, silver, tin, copper or chromium. The thicknesses of the one or more deposited layers are within the usual range known to the person skilled in the art and are not essential to the invention.

Suitable electrolyte solutions that can be used to coat electrically conductive structures are those skilled in the art, for example, Werner Jillek, Gustl Kepler, Manual of printed circuit board technology. Eugen G. Leuze Verlag, 2003, Volume 4, pages 332-352 known.

For coating the electrically conductive structured or full surface on the carrier, the carrier is first supplied to the bath with the electrolyte solution. The carrier is then conveyed through the bath, wherein the electrically conductive particles contained in the previously applied structured or full-surface base layer are contacted with at least one cathode. In this case, any customary knew, suitable cathode used. As long as the cathode contacts the structured or solid surface, metal ions are deposited from the electrolyte solution to form a metal layer on the surface.

A suitable device, in which the structured or full-surface electrically conductive base layer is galvanically coated, generally comprises at least one bath, one anode and one cathode, wherein the bath contains an electrolyte solution containing at least one metal salt. From the electrolytic solution, metal ions are deposited on electrically conductive surfaces of the substrate to form a metal layer. The at least one cathode is for this purpose brought into contact with the base layer of the substrate to be coated, while the substrate is conveyed through the bath.

For galvanic coating, all electroplating processes known to those skilled in the art are suitable. Such electroplating processes are, for example, those in which the cathode is formed by one or more rollers which contact the material to be coated. The cathodes can also be designed in the form of segmented rolls, in which in each case at least the segment of the roll, which is in communication with the substrate to be coated, is connected cathodically. In order to remove metal deposited on the roll, it is possible for segmented rolls to anodize the segments which do not contact the base layer to be coated, thereby depositing the metal deposited thereon back into the electrolyte solution.

In one embodiment, the at least one cathode comprises at least one band with at least one electrically conductive portion, which is guided around at least two rotatable shafts. The waves are carried out with a suitable, matched to the respective substrate cross-section. Preferably, the waves are cylindrically shaped and may for example be provided with grooves in which the at least one band runs. For electrically contacting the band, preferably at least one of the cores is cathodically connected, wherein the shaft is designed such that the current is transmitted from the surface of the shaft to the band. If the shafts are provided with grooves in which the at least one belt runs, the substrate can be contacted simultaneously via the shafts and the belt. However, only the grooves can be electrically conductive and the regions of the waves between the grooves can be made of an insulating material in order to avoid that the substrate is also electrically contacted via the waves. The power supply of the waves takes place for example via slip rings, but it can also be used any other suitable device with which power can be transmitted to rotating shafts. Because the cathode comprises at least one band with at least one electrically conductive section, substrates with short electrically conductive structures, especially in the transport direction of the substrate, can also be provided with a sufficiently thick coating. This is possible because, as a result of the design of the cathode as a band, even short electrically conductive structures are in contact with the cathode for a longer time.

In order to coat also the regions of the electrically conductive structure on which the band designed as a cathode rests for contacting, preferably at least two bands are arranged offset one behind the other. The arrangement is generally such that the second band, which is arranged offset behind the first band, contacts the electrically conductive structure in the region on which the metal was deposited during the contacting with the first band. A greater thickness of the coating can be achieved by designing more than two bands in succession.

A shorter construction, seen in the direction of transport, can be achieved in that successive, staggered bands are guided over at least one common shaft.

The at least one band can, for example, also have a network structure so that only small areas of the electrically conductive structures to be coated on the substrate are covered by the band. The coating takes place in each case in the holes of the network. In order to coat the electrically conductive structures in the areas in which rests the network, it is also advantageous in the case that the bands are formed in the form of a network structure, at least two bands arranged one behind the other.

It is also possible that the at least one band comprises alternating conductive and non-conductive sections. In this case, it is possible to additionally guide the band around at least one anodically connected wave, wherein care should be taken that the length of the conductive portions is smaller than the portion between a cathodic and an adjacent anodically connected wave. In this way, the regions of the ribbon which are in contact with the coated substrate are switched cathodically, and the regions of the ribbon which are not in contact with the substrate become anodic. The advantage of this circuit is that metal which deposits on the tape during the cathodic circuit of the tape is removed during the anodic circuit. In order to remove all the metal deposited on the tape while it was cathodically connected, the anodically connected region is preferably se longer or at least as long as the cathodically connected area. On the one hand, this can be achieved by virtue of the fact that the anodically connected shaft has a larger diameter than the cathodically connected shaft; on the other hand, it is also possible to provide at least the same or smaller diameter of the anodically connected shafts, at least as many as cathodically connected shafts Distance of the cathodically connected waves and the distance of the anodically connected waves is preferably the same size.

Alternatively, it is also possible for the cathode to comprise at least two disks rotatably mounted on one shaft in each case instead of the belts, the disks meshing with one another. This also makes it possible that short electrically conductive structures, especially in the transport direction of the substrate, can be provided with a sufficiently thick and homogeneous coating. The disks are generally designed in a cross-section adapted to the respective substrate. The disks preferably have a circular cross section. The waves can be any

Have cross-section. Preferably, however, the shafts are cylindrical.

In order to be able to coat structures which are wider than two adjacent disks, several disks are arranged next to one another on each shaft, depending on the width of the substrate. In each case, a sufficient distance is provided between the individual disks, in which the disks of the following shaft can engage. In a preferred embodiment, the distance between two disks on a shaft corresponds at least to the width of a disk. This makes it possible that in the distance between two discs on a shaft, a disc can engage another shaft.

The power supply of the discs takes place for example via the shaft. This makes it possible, for example, to connect the shaft outside the bath with a voltage source. This connection is generally made via a slip ring. However, any other connection is possible with which a voltage transfer from a stationary voltage source is transmitted to a rotating element. In addition to the power supply via the source, it is also possible to supply the contact disks on their outer circumference with power. For example, sliding contacts, such as brushes, may be in contact with the contact disks on the side facing away from the substrate.

In order to supply the disks, for example, with electricity via the shafts, the shafts and the disks are preferably made at least in part from an electrically conductive material. However, it is also possible to remove the waves from an electrically insulated producing material and to provide the power supply to the individual panes, for example, by electrical conductors, such as wires. In this case, then the individual wires are each connected to the contact discs, so that the contact discs are supplied with voltage.

In a preferred embodiment, the discs distributed over the circumference individual, electrically isolated from each other sections. The sections which are electrically insulated from one another are preferably switchable both cathodically and anodically. This makes it possible for a section which is in contact with the substrate to be switched cathodically, and as soon as it is no longer in contact with the substrate, it is connected in a nodal manner. As a result, deposited metal is removed during the cathodic circuit on the portion during the anodic circuit. The voltage supply of the individual segments generally takes place via the shaft.

In addition to the removal of the deposited on the shaft and the discs, or the bands, metal by reversing the waves or bands other cleaning variants, for example, a chemical or mechanical cleaning, possible.

The material from which the electrically conductive parts of the disks or the bands are made, is preferably an electrically conductive material, which does not pass into the electrolyte solution during operation of the device. Suitable materials include metals, coated metals, graphite, conductive polymers such as polythiophene or metal / plastic composites. Preferred materials are stainless steel and / or titanium, coated titanium such as iridium, tantalum, ruthenium mixed oxide coated titanium or platinum coated titanium.

It is also possible to connect several baths with different electrolyte solutions in succession, in order to deposit several different metals on the base layer to be coated in this way. Furthermore, it is also possible first to deposit electrolessly metal and then electrolessly on the base layer. In this case, different metals or even the same metal can be deposited by the electroless and / or the galvanic deposition.

The galvanic coating apparatus may further be provided with a device with which the substrate can be rotated. The axis of rotation of the device, with which the substrate can be rotated, is perpendicular to the to be coated Surface of the substrate arranged. By rotating electrically conductive structures, which are initially seen in the transport direction of the substrate, wide and short, aligned so that they are seen after turning in the transport direction narrow and long.

The layer thickness of the metal layer deposited on the electrically conductive structure by the method according to the invention depends on the contact time, which results from the passage speed of the substrate through the device and the number of cathodes positioned behind one another, and the current intensity with which the device is operated. A higher contact time can be achieved, for example, by connecting several devices according to the invention in series in at least one bath.

In order to allow simultaneous coating of the top and bottom of the base layer, for example, two rollers or two shafts with the discs mounted thereon or two bands can be arranged so that the substrate to be coated can be passed between them.

If flexible films are to be coated whose length exceeds the length of the bath - so-called endless films, which are initially unwound from a roll, passed through the device for electroplating and then wound up again - this can also be zigzag-shaped, for example or in the form of a meander to several devices for electroplating, which can then be arranged, for example, one above the other or next to each other, are passed through the bath. The galvanic coating device may be equipped with any additional device known to those skilled in the art as needed. Such ancillary devices include, for example, pumps, filters, chemical feeders, roll-up and roll-down devices, etc.

To shorten the maintenance intervals, all methods of care of the electrolyte solution known to those skilled in the art can be used. Such care methods are, for example, systems in which the electrolyte solution regenerates itself.

The device according to the invention can also be operated, for example, in the pulse method known from Werner Jillek, Gustl Keller, Handbuch der Leiterplattentechnik, Eugen G. Leuze Verlag, Vol. 4, pages 192, 260, 349, 351, 352, 359. After the application of the structured and / or full-area, electrically conductive surfaces of the first level becomes at the positions at which interconnects of a second electrically conductive surface with the interconnects of the first structured, electrically conductive surface intersect and no contact between the first and the second Surface should arise, an insulating layer applied. The application of the insulating layer is preferably carried out by a printing or coating process. Suitable printing methods for applying the insulating layer are the same printing methods as described above for printing the first structured and / or full-area surface with the paste containing the electrically conductive particles. Preferably, the insulating layer is printed on the carrier by any printing method. Gravure printing, flexographic printing, offset printing, screen printing, inkjet printing or pad printing are preferred printing methods. In particular, for the production of fine structures, such as for the production of printed circuit boards, the ink jet printing method is suitable. It is also possible to apply the insulating layer by another conventional and well-known coating method. Such coating methods are, for example, casting, brushing, knife coating, brushing, spraying, dipping, rolling, tumbling, fluidized bed or the like.

Suitable materials for the insulating layer are, for example, binders having a pigmentary anchor group, natural and synthetic polymers and their derivatives, natural resins and synthetic resins and their derivatives, natural rubber, synthetic rubber, proteins, cellulose derivatives, drying and non-drying oils and the like. These can - but need not - be chemically or physically curing, for example air-hardening, radiation-curing or temperature-curing. Preferably, the material for the insulating layer is a polymer or polymer mixture.

Preferred polymers as the material for the insulating layer are ABS (acrylonitrile-butadiene-styrene); ASA (acrylonitrile-styrene-acrylate); acrylated acrylates; alkyd resins; Alkylvinylacetate; Alkylene vinyl acetate copolymers, in particular methylene vinyl acetate, ethylene vinyl acetate, butylene vinyl acetate; Alkylenvinylchlorid copolymers; amino resins; Aldehyde and ketone resins; Cellulose and cellulose derivatives, in particular alkylcellulose, cellulose esters, such as acetates, propionates, butyrates, cellulose ethers, carboxylalkylcelluloses, cellulose nitrate; Epoxy acrylate; epoxy resins; ethylene acrylic acid copolymers; Hydrocarbon resins; MABS (transparent ABS containing methacrylate units); maleic anhydride copolymers; Methacrylates, optionally amine-functionalized; Natural rubber; synthetic rubber; Chlorinated rubber; Natural resins; rosins; Shellac; Phenol resins; Polyester; poly- ester resins, such as phenyl ester resins; polysulfones; polyether; polyamides; polyimides; polyanilines; polypyrroles; Polybutylene terephthalate (PBT); Polycarbonate (for example, Makro- ^Ion® from Bayer AG); polyester; polyether; polyethylene; Polyethylenthiofene; polyethylene naphthalates; Polyethylene terephthalate (PET); Polyethylene terephthalate glycol (PETG); polypropylene; Polymethylene methacrylate (PMMA); Polyphenylene oxide (PPO); Polytetrafluoroethylene (PTFE); polytetrahydrofuran; Polyvinyl compounds, in particular polyvinyl chloride (PVC), PVC copolymers, PVdC, polyvinyl acetate and copolymers thereof, optionally partially hydrolyzed polyvinyl alcohol, polyvinyl acetates, polyvinylpyrrolidone, polyvinyl ethers, polyvinyl acrylates and methacrylates in solution and as a dispersion and copolymers thereof, polyacrylic acid esters and polystyrene copolymers; Polystyrene (impact or not impact modified); Polyurethanes, uncrosslinked or mixed with isocyanates; polyurethane acrylates; Styrene-acrylic copolymers; Styrene-butadiene block copolymers (for example, Styroflex ^® or Styrolux ^® from BASF AG, K-Resin ™ CPC); Proteins, such as casein; SIS; PLC block copolymers. Furthermore, mixtures of two or more polymers may form the material for the insulating layer.

Particularly preferred polymers for the insulating layer are acrylates, acrylate resins, cellulose derivatives, methacrylates, methacrylate resins, melamine and amino resins, polyalkylenes, polyimides, epoxy resins, modified epoxy resins, for example bifunctional or polyfunctional bisphenol A or bisphenol F resins, epoxy novolac Resins, brominated epoxy resins, cycloaliphatic epoxy resins; aliphatic epoxy resins, glycidyl ethers, vinyl ethers, and phenolic resins, polyurethanes, polyesters, polyvinyl acetals, polyvinyl acetates, polystyrenes, polystyrene copolymers, polystyrene acrylates, styrene-butadiene block copolymers, alkylene vinyl acetates and vinyl chloride copolymers, polyamides and their copolymers. In the production of printed circuit boards, as the material for the insulating layer are preferably thermally or radiation-curing resins, for example, modified epoxy resins such as bifunctional or polyfunctional bisphenol A or bisphenol F resins, epoxy novolac resins, brominated epoxy resins, cycloaliphatic epoxy resins; aliphatic epoxy resins, glycidyl ethers, cyanate esters, vinyl ethers, phenolic resins, polyimides, melamine resins and amino resins, polyurethanes, polyesters and cellulose derivatives.

In a preferred embodiment, the material for the insulating layer is the same as the matrix material of the first structured, electrically conductive surface.

After the application of the insulating layer, the structured and / or full-surface, electrically conductive surface of the second plane is applied in a third step. The application of the structured and / or full-surface, electrically conductive surface of second level corresponds to the application of the structured and / or full-surface, electrically conductive surface of the first level.

After the application of the structured and / or full-area, electrically conductive surface of the second plane, it is possible in each case alternately to apply further insulating layers and structured and / or full-area, electrically conductive surfaces of further planes to the carrier.

The process according to the invention for the production of electrically conductive, structured or full surface surfaces on a support can be operated in a continuous, partially continuous or discontinuous manner. It is also possible that only individual steps of the process are carried out continuously while other steps are carried out discontinuously.

An advantage of the method according to the invention in the production of printed circuit boards is that with multilayer printed circuit boards a smaller number of inner layers is necessary, since a larger number of printed conductors and wirings can be realized on a defined surface. Since, according to the prior art, the individual layers are laminated together, the number of layers required for laminating is also reduced due to the omission of layers. If, with the method according to the invention, all printed conductors can be applied to a carrier, it is even possible that no laminating step is required at all.

The method according to the invention also reduces the number of holes in the printed circuit boards which were required for contacting printed conductors in different layers. Depending on the design of the circuit boards, it is even possible that no holes are needed at all. It is also possible that only holes are needed, which serve as mounting holes, but no more holes are needed by which interconnects on several layers are contacted electrically.

Another advantage is that the amount of insulation material can be reduced. Thus, it is necessary according to the prior art that an insulating material is applied over the entire area between the individual multilayer inner layers. This insulating material is for example glass fabric, resin or prepregs. Depending on the design of the circuit boards, these intermediate layers are completely eliminated, leaving only the carrier as the sole carrier of all circuit levels. By reducing the layers you will continue to get a flatter end product.

It is also possible to combine a conventional method for producing structured surfaces with the method according to the invention. Thus, for example, the support can first be produced by a conventional method, for example a resist or etching method. The structured and / or conductive surface on the carrier produced by the conventional method can then be further processed subsequently by the method according to the invention. As a next step, after the first structured and / or conductive surface has been produced on the support, the insulating layer is applied and then the application of a conductive printing paste takes place. Subsequently, the printing paste is dried and / or cured and then optionally electrolessly and / or electroplated.

The inventive method allows cost-effective production of printed conductors on electrically non-conductive substrates. In addition, the method according to the invention is a flexible method, whereby a quick layout change is possible.

The method according to the invention is suitable, for example, for the production of printed circuit boards. Such printed circuit boards are, for example, those with multilayer inner and outer layers, microvias, chip-on-board, flexible and rigid printed circuit boards and are incorporated, for example, in products such as computers, telephones, televisions, automotive electrical components, keyboards, radios, video, CD, CD-ROM and DVD players, game consoles, measuring and control devices, sensors, electrical kitchen appliances, electric toys, etc.

Also, with the method according to the invention, electrically conductive structures can be coated on flexible circuit carriers. Such flexible circuit carriers are, for example, plastic films made of the materials mentioned above for the carrier, on which electrically conductive structures are printed. Furthermore, the method according to the invention is suitable for the production of RFI D antennas, transponder antennas or other antenna structures, chip card modules, flat cables, seat heaters, foil conductors, printed conductors in solar cells or in LCD or plasma picture screens, capacitors, film capacitors, resistors, convectors or electrical fuses. Furthermore, with the method according to the invention, it is also possible, for example, to produce 3D molded interconnect devices. The production of antennas with contacts for organic electronic components as well as coatings on surfaces consisting of electrically non-conductive material for electromagnetic shielding (shielding) is also possible.

A use is further possible in the field of flowfields of bipolar plates for use in fuel cells.

The scope of application of the method according to the invention enables a cost-effective production of metallized, even non-conductive substrates, in particular for use as switches and sensors, absorbers for electromagnetic radiation or gas barriers or decorative parts, in particular decorative parts for motor vehicle, sanitary, toy, household and office space and packaging as well as foils. Also in the field of security printing for bills, credit cards, identity papers, etc., the invention may find application. Textiles can be electrically and magnetically functionalized using the method according to the invention (antennas, transmitters, RFID and transponder antennas, sensors, heating elements, anti-static (also for plastics), shielding, etc.).

Furthermore, the production of contact points or contact pads or wiring on an integrated electrical component is possible.

Preferred uses of the substrate surface metallized according to the invention are those in which the substrate thus produced is used as a printed circuit board, RFI D antenna, transponder antenna, seat heating, flat cable, foil conductor, conductor tracks in solar cells or in LCD or plasma picture screens, contactless chip card or as a decorative application, for example for packaging materials.

After the galvanic coating, the substrate can be further processed according to all steps known to those skilled in the art. For example, existing electrolyte residues can be removed from the substrate by rinsing and / or the substrate can be dried. Likewise, for example, the multilayer inner layers produced by the process according to the invention can be processed into multilayer printed circuit boards. Furthermore, for example, holes, vias, blind holes, etc. may subsequently be applied and metallized on printed circuit boards with the aim of making a through-connection of the upper and lower printed circuit board sides. An advantage of the method according to the invention is that sufficient coating is possible even when using materials for the electrically conductive particles which oxidize easily.

In the following the invention will be described in more detail with reference to a drawing. The figures show only one possible embodiment by way of example. Of course, except in the listed embodiments, the invention can also be implemented in further embodiments or in combination of these embodiments.

Show it

FIG. 1 shows a 3D representation of a structured, electrically conductive surface of a first layer,

FIG. 2 shows a 3D representation of the structured, electrically conductive surface according to FIG. 1 with an insulating layer,

FIG. 3 shows a 3D representation according to FIG. 2 with an additional electrically conductive

Surface of a second level,

Figure 4 is a sectional view of two crossing electrically conductive surfaces with intermediate insulating layer.

FIG. 1 shows by way of example in a 3D representation a section of a carrier 1 on which a structured, electrically conductive surface 3 of a first plane is applied. The structured, electrically conductive surface of the first level illustrated here by way of example comprises a conductor track 5 and a contact surface 7, on which the structured, electrically conductive surface 3 of the first plane can be contacted with a structured, electrically conductive surface of a further plane.

The structured, electrically conductive surface 3 of the first plane is preferably applied to the carrier 1 as above. The structured, electrically conductive surface 3 of the first plane is preferably applied to the carrier 1 by initially printing the structured, electrically conductive surface 3 with a paste containing electrically conductive particles in a matrix material, and subsequently at least partially exposing the particles exposed and then provided by electroless and / or galvanic coating with a metal layer. After the application of the structured, electrically conductive surface 3 of the first plane, as shown in FIG. 2, an insulating layer 9 is applied. In the embodiment illustrated here, the insulating layer 9 covers a part of the conductor track 5 of the structured, electrically conductive surface 3. The insulating layer 9 is attached to a position at which the conductor track 5 of the structured, electrically conductive surface 3 of the first plane is crossed by a conductor track of a structured, electrically conductive surface of a further plane. The insulating layer 9 is also applied as described above. Preferably, the insulating layer 9 is printed.

After the application of the insulating layer, as shown by way of example in FIG. 3, a structured, electrically conductive surface 11 of a second plane is applied. The structured, electrically conductive surface 11 of the second level comprises a conductor track 13 and a contact surface 15. In the exemplary embodiment shown here in three dimensions, the conductor track 13 of the structured, electrically conductive surface 11 of the second plane is U-shaped. A first leg 17 of the U-shaped conductor track crosses the conductor track 5 of the structured, electrically conductive surface 3 of the first plane at the position at which the insulating layer 9 has been applied. The second limb 19 ends with the contact surface 15 at the position at which the contact surface 7 of the structured, electrically conductive surface 3 of the first plane is located. The contact surface 15 of the structured, electrically conductive surface 1 1 of the second plane and the contact surface 7 of the structured, electrically conductive surface 3 of the first plane are in contact with one another such that current flows from the structured, electrically conductive via the contact surfaces 7, 15 Surface 3 of the first level to the structured, electrically conductive surface 1 1 of the second level can be transmitted. The contact surfaces 7, 15 are preferably formed such that the cross-sectional area of the lower contact surface, here the contact surface 7 of the first plane is greater than the cross-sectional area of the upper contact surface, here the contact surface 15 of the second plane. In order to avoid a short circuit, at the point at which the second limb 17 of the U-shaped conductor track 13 of the structured, electrically conductive surface 11 of the second plane crosses the conductor track 5 of the structured, electrically conductive surface 3 of the first plane, the insulating layer 9 is formed such that it is located between the conductor track 5 of the structured, electrically conductive surface 3 of the first plane and the conductor track 13 of the structured, electrically conductive surface 11 of the second plane.

The structured, electrically conductive surface 11 of the second plane is preferably applied in the same way as the structured, electrically conductive surface 3 of the first plane. However, it is also possible, the first level with a conventional method, for. As etching, apply and the second level with the inventive method. Furthermore, it is possible to apply the structured, electrically conductive surfaces of the individual planes using different methods.

FIG. 4 shows a sectional view of a carrier 1, on which a structured, electrically conductive surface 3 of a first plane and a structured, electrically conductive surface 11 of a second plane intersect. In order that no current is transmitted from the structured, electrically conductive surface 3 of the first plane to the structured, electrically conductive surface 11 of the second plane, an insulating layer 9 is formed between the structured, electrically conductive surfaces 3, 11.

Claims

claims

1. A process for the production of structured and / or full surface, electrically conductive surfaces (3, 1 1) on an electrically non-conductive support (1), comprising the following steps:

a) applying the structured and / or full-surface, electrically conductive surfaces (3) of a first plane to the electrically non-conductive support (1),

b) applying an insulating layer (9) at the positions at which structured and / or full-surface electrically conductive surfaces (11) of a second plane crossing the structured and / or full-surface, electrically conductive surfaces (3) of the first plane and no electrical contact between the structured and / or full-area, electrically conductive surfaces of the first level (3) and the second level (1 1) should take place,

c) applying the structured and / or full-surface, electrically conductive surfaces (1 1) of the second level according to step a),

d) optionally repeating steps b) and c).

2. The method according to claim 1, characterized in that the structured and / or full-area, electrically conductive surface in step a) is applied by first applied a base layer with a dispersion containing electrically conductive particles in a matrix material, and at least partially cured and / or dried, then the particles are at least partially exposed and then provided by electroless and / or electroplating with a metal layer.

3. The method according to claim 2, characterized in that the exposure of the electrically conductive particles takes place chemically, physically or mechanically.

4. The method according to claim 2 or 3, characterized in that the exposure of the electrically conductive particles is carried out with an oxidizing agent.

5. The method according to claim 4, characterized in that the oxidizing agent potassium permanganate, potassium manganate, sodium permanganate, sodium manganate, water hydrogen peroxide or its adducts, sodium perborate, sodium percarbonate, sodium persulfate, sodium peroxodisulfate, sodium hypochlorite or sodium perchlorate.

6. The method according to claim 2 or 3, characterized in that the exposure of the electrically conductive particles by the action of substances which dissolve the matrix material, attach and / or swell, takes place.

7. The method according to claim 6, characterized in that the substance which dissolve the matrix material, attach and / or swell, is an acidic or alkaline see chemical or chemical mixture or a solvent.

8. The method according to any one of claims 2 to 7, characterized in that before the electroless and / or galvanic coating of the structured or full-surface base layer, an optional oxide layer is removed from the electrically conductive particles.

9. The method according to any one of claims 1 to 8, characterized in that the carrier is cleaned prior to application of the structured and / or full-surface, electrically conductive surface by a dry process, a wet chemical process and / or a mechanical process.

10. The method according to claim 9, characterized in that the dry process is a dedusting by brushing and / or deionized air, low-pressure plasma, Corona discharge or particle removal by provided with an adhesive layer rolls or rollers, the wet-chemical process rinsing with an acidic or alkaline chemical or chemical mixture or a solvent and the mechanical method is brushing, grinding, polishing or pressure blasting with an air or water jet optionally containing particles.

1 1. A method according to any one of claims 1 to 10, characterized in that the material for the insulating layer is a polymer or a polymer mixture.

12. The method according to any one of claims 1 to 1 1, characterized in that the base layer is applied by a coating method.

13. The method according to any one of claims 1 to 12, characterized in that the base layer by any printing method, preferably an ink jet jerk process, a screen printing process, a screen printing process, a pad printing process or an offset printing process, is printed on the support.

14. The method according to any one of claims 1 to 13, characterized in that the insulating layer by any printing method, preferably an inkjet d jerk process, a Rollend jerking, a screen printing process, a pad printing process or an offset printing process is printed.

15. The method according to any one of claims 1 to 14, characterized in that the insulating layer is at least partially dried after application and / or at least partially physically and / or chemically cured.

16. The method according to any one of claims 1 to 15, characterized in that the structured and / or full-surface, electrically conductive surfaces are applied to the upper side and on the underside of the substrate.

17. The method according to claim 16, characterized in that the structured, electrically conductive surfaces on the top and bottom of the substrate are electrically connected to each other by bores are provided in the substrate, the walls of which are provided by the galvanic coating with a metal layer.

18. Process according to one of claims 1 to 17, characterized in that the electrically non-conductive material from which the carrier is made, a resin-impregnated fabric or glass fiber-reinforced plastic pressed into plates or rollers, a plastic film, a ceramic material, glass, silicon or a textile is.

19. The method according to any one of claims 1 to 18 for the production of printed conductors on printed circuit boards, RFID antennas, transponder antennas or other antenna structures, smart card modules, flat cables, Seitzheizungen, film conductors, printed conductors in solar cells or in LCD or plasma screens or for the production of electroplated products in any form.

20. The method according to any one of claims 1 to 18 for the production of decorative or functional surfaces on products that are used to shield electromagnetic radiation, for heat conduction or as packaging.

21. An apparatus comprising an electrically nonconductive support having thereon, electrically conductive surfaces, wherein the electrically conductive surfaces are arranged in at least two planes and at the intersections of the conductive structures of the at least two levels an insulating layer may be formed, characterized in that the electrically conductive surfaces one

Base structure of electrically conductive particles contained in a matrix material, which are coated with a metal layer, and the insulating layer consists of a printable, electrically insulating material.

22. The apparatus of claim 21, prepared by a method according to any one of claims 1 to 20.