EP0166360A2 - Process for activating substrates for electroless plating - Google Patents

Abstract

Activation baths containing an organometallic compound based on elements of sub-group 1 or 8 of the periodic table with a "guest/host" interrelationship are outstandingly suitable for electroless metallization of preferably non-metallic substrates. Activators of palladium compounds and cyclic crown ethers are particularly suitable.

Description

It is known that solutions or dispersions of salts of the elements of the 1st or 8th subgroup of the Periodic Table of the Elements in polar organic solvents can be used to activate non-metallic substrates for wet-chemical metallization (cf., for example, US Pat. No. 1,154,152 and DE-A 2 934 584).

• - ein vorheriges Beizen der zu metallisierenden Substratoberfläche erfordern,
• - nur für bestimmte Substrate, z.B. wie AcrylnitrilButadien-Styrolcopolymerisate geeignet sind,
• - einen zusätzlichen Komplexierungs- bzw. Reduzierungsschritt erfordern,
• - nicht in schnell trocknenden aprotischen Lösemitteln durchführbar sind, da die Edelmetallsalze darin unlöslich sind.

The disadvantage of these methods is that they

• require prior pickling of the substrate surface to be metallized,
• - are only suitable for certain substrates, e.g. acrylonitrile-butadiene-styrene copolymers,
• - require an additional complexation or reduction step,
• - cannot be carried out in fast-drying aprotic solvents, since the precious metal salts are insoluble in them.

It is also known that solutions or dispersions of the Pd-O complexes of _O C, B-unsaturated ketones (cf. DE-A 2 451 217) or the complexes of N-containing compounds (cf. DE-A 2 116 389) can be used to activate substrate surfaces. However, these processes also require an oxidative degradation treatment of the surfaces to be metallized, as a result of which their technical application is also restricted to certain substrates. In addition, they must also be post-treated with the aid of reducing agents or complexing agents so that they catalytically enable electroless metal deposition in the subsequent metallization step. In addition, the systems mentioned have the disadvantage that they are only sufficiently soluble in comparatively toxic aromatics and not in the commercially available solvents, such as 1,1-dichloroethane, trichlorethylene, ethanol and cyclohexane, and they show insufficient storage stability.

DE-A 2 934 584 also discloses water-containing activation baths which contain reaction products of noble metal-halogen complexes with polyglycol (ethers). These activation solutions have the disadvantage, among other things, that the substrates treated with them have to be heat-treated or treated with washing baths before the metallization because of the high boiling points of the polyglycols, as a result of which part of the activator is lost.

Finally, elegant activation systems based on complex compounds of the elements of the 1st or 8th subgroup of the periodic table are known which have an additional functional grouping for improving adhesion (cf. DE-A 3 148 280). With the help of functional groups matched to the respective substrate, different substrates such as glass, ceramics, polyester, polyamide and ABS plastics can be provided with an adhesive metal coating without prior pickling. However, these elegant activation systems also have the disadvantage that they are only limited under conditions customary in the technology of plastic electroplating, in the best case they are stable in storage for a few months. This limited storage stability is only guaranteed if the activators are dissolved in specially cleaned solvents.

For this reason, technical solvents, which contain common impurities, stabilizers and foreign ions, have to be freed from these components at great expense, which additionally increases the process costs.

Another disadvantage of these systems is that they cannot be used in technically interesting solvents which are capable of forming complexes, such as dimethylformamide (DMF), dimethyl sulfoxide (DMSO), methyl ethyl ketone and pentanedione (2,4). They are stabilized in these media by additional complex formation so that they no longer have a catalytic effect.

The object of the present invention is now to develop activation systems which are readily soluble in aprotic solvents and have virtually unlimited storage stability on the basis of organometallic compounds of the elements of the 1st and 8th subgroups of the periodic table, which are also distinguished by their excellent stability to moisture, Characterize atmospheric oxygen, common solvent stabilizers and impurities and their activation properties remain almost unaffected by the solvents which can form complexes.

This object is achieved according to the invention in that the organometallic compounds used are those with a "host / guest" interrelation.

Compounds consisting of selective complex ligands or host molecules and the guest ion or molecule to be complexed are generally known.

As selective complex ligands, cyclic or acyclic compounds come into question which, because of their chemical and / or physical nature, are a host molecule or, in the presence of ionogenic or neutral compounds to be complexed, assume the form required for complex or adduct formation, the polar regions being present in the presence of the to be directed towards the complexing medium.

As is known, the selectivity of the host molecule with respect to the guest ion or molecule to be complexed depends on its ring size, steric structure or chemical nature (whether polar or hydrophobic). There are numerous selective host molecules in the literature which are associated with the alkali or alkaline earth metal cations such as Li ⁺ , Na ⁺ , K ⁺ , Ca ²⁺ or NH ₄ ⁺ [cf. E. Weber, "Contacts" (Darmstadt) 1, (1984) and JG Schindler, "Bioelectrochemical Membrane Electrodes" pp. 77-104, Walter de Gruyter Verlag, Berlin / New York (1983) 7 or with heavy metal ions such as Co Ni ²⁺ , Fe, Cd ²⁺ and Ag as well as with anions such as C1 and S0 ₄ ² [cf. The work cited above by JG Schindler, pp. 104-1127 and with the neutral ligands or compounds can form a selective guest-host complex.

All host complex ligands which contain heteroatoms (0, N and S) in their chain are suitable for carrying out the novel process. Crown ethers, cryptands and podands or their derivatives and cyclic peptides are particularly suitable; furthermore, ester-linked macrolides containing tetrahydrofuran and analogous compounds based on heteroatoms such as S and N, which are known, for example, in biological systems as transport regulators.

A definition of the terms "Kronenether", "Cryptande" and "Podanden" can be found in the reviews F. Vögtle, "Contacts" (Darmstadt) (1977) and (1978), E. Weber, "Contacts" (Darmstadt) (1984) as well Vögtle Chemikerzeitung 97, 600 - 610 (1973).

To carry out the process according to the invention, substituted or unsubstituted host ligands based on cyclic or acyclic crown ethers, which may additionally contain heteroatoms such as N and S in their ring system, are particularly preferably used. Such compounds are described in DE-A 2 842 862 and EP-A 10 615 and correspond e.g. the formulas

R = Alkyl oder Aryl; z.B. Methyl, Ethyl, Phenyl, Biphenyl, Phenylazophenyl u.a.

R = alkyl or aryl; eg methyl, ethyl, phenyl, biphenyl, phenylazophenyl and others

The cyclic compounds mentioned above are preferred.

Another variant of carrying out the process according to the invention is that the host molecules mentioned are covalently incorporated into polymeric or oligomeric compounds and then complexed with the desired activation media. Such oligomeric or polymeric systems are known and are described, for example, in "Novel Polyurethanes with Macroheterocyclic (Crown-Ether) Structures in the Polymer Backbone", J.E. Herweh, J. of Polymer Science: Polymer Chemistry Edition, Vol. 21, 3101 (1983).

• 1) aus Verbindungen der Formel
  
  
  worin Me für Wasserstoff-, Alkali- oder Erdalkaliatome bzw. Schwermetallatome (Fe, Co, Ni oder Cu) oder für NH₄, Hal für Halogen (vorzugsweise Cl und Br) und E für ein Edelmetallatom der 1. oder 8. Nebengruppe des Periodensystems, (vorzugsweise Pt, Pd und Au) mit der Wertigkeit m und der Koordinationszahl z steht, wobei z-m=n ist, oder
• 2) aus der Kationen, der besagten Elemente vorzugsweise Ag⁺, Cu²⁺ und Cu⁺ oder vorzugsweise
• 3) aus nichtkomplexen Salzen dieser Elemente der Formel
  
  
  oder
• 4) aus üblichen Kolloidal-Systemen dieser Edelmetalle gebildet.

The inorganic part of the host / guest molecules is preferred

• 1) from compounds of the formula
  
  
  wherein Me for hydrogen, alkali or alkaline earth metal or heavy metal atoms (Fe, Co, Ni or Cu) or for NH ₄ , Hal for halogen (preferably Cl and Br) and E for a noble metal atom of the 1st or 8th subgroup of the periodic table , (preferably Pt, Pd and Au) with the valency m and the coordination number z, where zm = n, or
• 2) from the cations, said elements preferably Ag ⁺ , Cu ²⁺ and Cu ⁺ or preferably
• 3) from non-complex salts of these elements of the formula
  
  
  or
• 4) formed from conventional colloidal systems of these precious metals.

Precious metal compounds to be used with preference are those of the formula H ₂ PdC1 ₄ , Na ₂ (PdCl ₂ Br ₂ ), Na ₂ PdCl ₄ , Ca PdCl ₄ , Na ₄ (PtCl ₆ ), AgNO ₃ , HAuCl ₄ and CuCl. The Pd compounds are preferred.

Suitable colloidal noble metal systems are derived primarily from the metals Pd, Pt, Au and Ag and are, for example, in "plastic electroplating" by R. Weiner, Eugen G. Leuze Verlag, Saulgau / Württ. (1973), pages 180-209.

For the case specified in point 1), the electrically neutral ligand takes up the cation M ^{n +} in its endohydrophilic cavity at the phase boundary and transports it into the organic solvent phase, the part [E ^{m +} Hal _z ^- ], in due to the potential gradient the desired solvent phase is also transported. This phenomenon is basically for the Systems listed in points 2), 3) and 4) are relevant.

The activation solution can be prepared by dissolving the host molecule in a suitable aprotic solvent with a boiling point at 80 ° C. such as perchlorethylene, 1,1,1-trichloroethane, CH ₂ C1 ₂ , petroleum ether or chloroform and adding the noble metal system according to the principle already mentioned.

Another possibility for producing the activation systems according to the invention is that the said noble metals are initially introduced in an aqueous phase and, in accordance with the principle mentioned, they are diffused or complexed into an organic phase which contains the complex-forming host molecules, and the organic phase is separated from the aqueous phase , optionally neutral washed, freed from the solvent by recrystallization or evaporation and then used in a desired liquid medium for the activation.

Although such systems have an unlimited shelf life in protic and aprotic solvents under conditions customary in the art of plastic electroplating, they surprisingly have good activation properties for electroless chemical metallization.

Since they diffuse extremely well both in microporous or macroporous membrane matrices and in inorganic porous solids, they are outstandingly suitable both for metal doping and for activation for the subsequent continuous electroless metallization of such porous systems.

The activators to be used according to the invention diffuse in microscopic cavities (free volumes) of common polymers, with the result that additional adhesion of the activation nuclei or electrolessly deposited metal coatings is achieved. The exact definition of "free volume theory" can be found in the review J. Crank "The Mathematics of Diffusion" Oxford University Press, London (1975).

The activators can be used in concentration ranges from 0.001 g / 1 (based on the noble metal) up to the respective solubility limit. It is preferable to work with 0.1 to 3.0 g / 1 of these substances.

Thanks to their high storage stability (no clouding of the solutions - sometimes after weeks of storage) and their strong sorption in the ultraviolet and / or visible spectral range, they are ideal for continuous concentration monitoring with a photometer.

Otherwise, the sorption properties of the complex compounds to be used according to the invention can be increased further by introducing special substituents (in particular NO ₂ , -NR ₃ , -S0 ₃ H and -CN).

The influence of electron-withdrawing or electron-donating substituents on the light absorption properties of carbon molecules is known and can be found, for example, in D.H. Williams and J. Flemming "Spectroscopic methods in organic chemistry", Georg Thieme Verlag Stuttgart (1971).

To increase the pull-off strength of the activator or metal layer, the said host molecules can additionally be provided with a further functional group.

In certain cases a very good adhesive strength of the substrate surface is achieved with the further functional group, this adhesive strength being due to a chemical reaction with the substrate surface or to an adsorption or absorption.

Functional groups such as carboxylic acid groups, carboxylic acid halide groups, carboxylic acid anhydride groups, carbonic ester groups, carbonamide and carbonimide groups, aldehyde and ketone groups, ether groups, sulfonamide groups, sulfonic acid groups and sulfonate groups, sulfonic acid halide are particularly suitable for chemical anchoring of the activator on the substrate surface groups, sulfonic acid ester, halogen-containing heterocyclic radicals, such as chlorotriazinyl, -pyrazinyl-, -pyrimidinyl- or chloroquinoxalinyl, activated double bonds, such as relatively long-chain at vinylsulfonate or acrylic acid derivatives, amino groups, hydroxyl groups, isocyanate groups, olefinic groups and acetylenic groups and Hercaptogruppen and epoxide groups, further Alkyl or alkenyl radicals from C ₈ , in particular oleic, linoleic, stearic or palmiting groups.

If there is no anchoring by a chemical reaction, the adhesive strength can also be brought about by absorption of the organometallic activators on the substrate surface, the causes of the absorption being e.g. Hydrogen bonds or Waals forces.

It is expedient to match the functional groups which cause adsorption to the particular substrate. For example, Long-chain alkyl or alkenyl groups in the activator molecule improve the adhesive strength on substrates made of polyethylene or polypropylene. In contrast, activators with, for example, additional carbonyl or sulfone groups are particularly favorable for metallizing objects based on polyamide or polyester.

Functional groups such as carboxylic acid groups and carboxylic acid anhydride groups are particularly suitable for anchoring the activator to the substrate surface by adsorption.

In practice, the new activation process is generally carried out by wetting the substrate surfaces to be metallized with a solution of the selective metal complex in a suitable organic solvent, removing the solvent and, if appropriate, sensitizing it with a suitable reducing agent. The substrate pretreated in this way can then be metallized in a conventional metallization bath.

Suitable solvents are, in addition to the above-mentioned perchlorethylene, 1,1,1-trichloroethane, CH ₂ ci ₂ , n-hexane, petroleum ether, cyclohexanone, alcohols, such as n-butanol, isopropanol, tert-butanol, ketones such as methyl ethyl ketone, aldehydes such as n -Butanal-1, DMF and DMSO.

If the organometallic compound contains ligands which allow chemical fixation on the substrate surface, activation from the aqueous phase may also be possible.

Suitable reducing agents for sensitization are aminoboranes, alkali hypophosphites, alkali borohydrides, hydrazine hydrate and formalin. The substrates can be wetted by spraying, printing, impregnation or impregnation.

In order to increase the adhesion of the metal coating to the carrier surface, such solvents or solvent mixtures are used which lead to dissolution or swelling of the plastic surface to be metallized, particularly preferably used to carry out the method according to the invention.

The action of the activator systems with their characteristic swelling action on the substrates results in a type of "adhesion nucleation" which can perhaps be imagined in such a way that there are gaps accessible to the activation nuclei on the substrate surface, to which the metals deposited during electroless metallization are anchored .

The surface change caused by the "swelling adhesion nucleation" is noticeable by a change in the light separation, cloudiness, light permeability (in the case of transparent films and plates), change in layer thickness or in scanning electron microscope images in the form of cracks, caverns or vacuoles.

The swelling agent suitable for the particular polymer substrate to be metallized must be determined from case to case by means of appropriate preliminary tests. A swelling agent behaves optimally if it swells the surfaces of the substrates within reasonable times without completely dissolving the substrate or even negatively influencing its mechanical properties such as notch impact strength and without changing the organometallic activators.

Suitable swelling agents are the so-called e-solvents or their blends with precipitants, as described, for example, in the "Polymer Handbook" J. Brandrup et al, New York, IV, 157-175, (1974).

The solvents are removed from the wetted substrates simply by evaporation or, in the case of higher-boiling compounds, by extraction.

According to a preferred method variant, the activation baths are monitored with a photometer as a detector. The wavelength of the filter should correspond to the absorption maximum of the solution.

The measurement signal is recorded with a compensation recorder and called up from a clock generator at intervals of 0.1 seconds to several minutes. With the help of a computer, the missing components (solvent, activator) can be added.

A very particularly preferred embodiment of the method according to the invention consists in that the reduction in the metallization bath is carried out immediately with the reducing agent of the electroless metallization. This embodiment is particularly suitable for nickel baths containing amine borane or copper baths or silver baths containing formalin.

The metallization baths which can be used in the processes according to the invention are preferably baths with Ni, Co, Cu, Au, Ag salts or mixtures thereof or with iron salts. Such baths are known in the art of electroless metallization of plastics.

Suitable substrates for the process according to the invention are: steels, titanium, glass, aluminum, textiles and fabrics based on natural and / or synthetic polymers, ceramics, carbon, paper, thermoplastics such as polyamide types, ABS (acrylonitrile butadiene styrene) polymers, Polycarbonates, polypropylene, polyester, polyethylene, polyhydantoin, thermosets such as epoxy resins, melamine resins, as well as their mixtures or copolymers.

• - Die eingesetzten Verbindungen zur Aktivierung von Substratoberflächen dürfen nicht zu einer irreversiblen Zerstörung des Metallisierungsbades führen.
• - Die lichtabsorptionsfähigen Substituenten dürfen nicht eine Fixierung der Aktivatoren an die Substratoberfläche verhindern.
• - Die lichtabsorptionsfähigen Substituenten dürfen nicht eine Komplexierung des Trägermolekuls mit den Elementen der 1. und 8. Nebengruppe verhindern.
• - Die besagten Elemente dürften mit Wirtsliganden keine so starke Wechselwirkung eingehen, daß sie eine Katalyse zur chemischen Metallabscheidung verhindern.
• - Die verwendeten Lösungsmittel dürfen nicht im Absorptionsbereich des Aktivators Eigenabsorption aufweisen, müssen leicht entfernbar sein und dürfen nicht zu einem chemischen Abbau der metallorganischen Verbindung sowie zum völligen Auflösen der Substrate führen.
• - Um eine ausreichende Aktivierung zu erzielen, soll die Aktivierungszeit von einigen Sekunden bis zu einigen Minuten betragen.

Without restricting the scope of the method according to the invention, it is advisable to observe the following parameters when carrying out the method:

• - The connections used to activate substrate surfaces must not lead to irreversible destruction of the metallization bath.
• - The light-absorbing substituents must not prevent the activators from being fixed to the substrate surface.
• - The light-absorbing substituents must not prevent complexation of the carrier molecule with the elements of subgroups 1 and 8.
• - The said elements should not interact with host ligands so strongly that they prevent catalysis for chemical metal deposition.
• - The solvents used must not be self-absorbing in the absorption area of the activator, must be easily removable and must not lead to chemical degradation of the organometallic compound and complete dissolution of the substrates.
• - To achieve sufficient activation, the activation time should be from a few seconds to a few minutes.

example 1

17.5 g of aqueous Na ₂ PdC1 ₄ solution (Pd content: 1.5% by weight) are mixed with 1 1 CH ₂ C1 ₂ (technical), which additionally contains 2.5 g of 1,4,7 Contains 10,13-pentaoxycylododecane, added at RT (room temperature). The mixture is stirred for 10 minutes before the aqueous phase is separated from the organic phase. You get a red-brown homogeneous activator solution. This solution is used to treat a plastic plate made of commercially available polyester with the dimensions 15 × 10 cm and 3 mm thick for 3 minutes. The substrate activated in this way is dried and then in an electroless nickel plating bath containing 30 g / 1 NiS0 ₄ . 5H20, 15 g / 1 dimethylamine borane 2n solution, 11.5 g / 1 citric acid and 3.0 g / 1 boric acid and adjusted to pH 7.9 with ammonia, metallized. After 20 minutes, a uniform, shiny metallic nickel coating with an electrical conductivity is deposited on the substrate surface.

Comparative example

17.5 g of aqueous Na ₂ PdC1 ₄ solution (Pd content: 1.5% by weight) are mixed with 1 1 CH ₂ C1 ₂ (technically) and stirred for 120 minutes (no reaction!). The sodium tetrachloropalladinite remains in the aqueous phase. The colorless organic phase is tested according to Example 1 for its activity for wet chemical metallization. Despite 120 minutes of treatment in the chemical metallization bath, no Ni can be deposited on the substrate surface.

Example 2

enthält, 5 Minuten bei RT haftaktiviert und getrocknet. Anschließend wird die Platte in einem Bad, bestehend aus

A 90 x 150 mm, 3 mm thick glass fiber reinforced (30 wt .-%) plastic plate made of polyamide-6 is in an activation bath, which

contains, 5 minutes at RT activated at RT and dried. The plate is then made up in a bath

• a) eine halbe Minute dekapieren in 10 %iger H₂S0₄
• b) Spülen
• c) 5 Minuten im Halbglanznickelbad, Spannung 9 Volt, Badtemperatur 60°C
• d) Spülen
• e) eine halbe Minute dekapieren
• f) 90 Minuten im Kupferbad; Spannung 1,9 Volt, Badtemperatur 28°C
• g) Spülen.

Sensitized for 5 minutes at RT, rinsed with distilled water and then nickel-plated in a conventional hypophosphite-containing nickel plating bath from Blasberg AG, Solingen, at 30 ° C. for 25 minutes. The adhesive strength of the metal pad, determined by the peel force according to DIN 53 494, is 40 N / 25 mm. The galvanic reinforcement of the above polyamide plate for the determination of the pull-off force was carried out as follows:

• a) Pick up half a minute in 10% H ₂ S0 ₄
• b) rinsing
• c) 5 minutes in a semi-gloss nickel bath, voltage 9 volts, bath temperature 60 ° C
• d) rinse
• e) Pick up half a minute
• f) 90 minutes in a copper bath; Voltage 1.9 volts, bath temperature 28 ° C
• g) rinse.

The preparation of 1,4,7,10,13-pentaoxycyclododecane sodium tetrachloropalladinite

0.3 mol of Na ₂ PdCl ₄ in 1 1 H ₂ O _dest are mixed with 5 1 CH ₂ Cl ₂ , which contains 0.9 mol of 1,4,7,10,13-pentaoxycyclodecane, at 40 ° C, 1 , Stirred for 5 hours and then cooled. The organic phase is separated from the aqueous. After filtering, the solvent is removed from the organometallic compound under vacuum. The new compound is then recrystallized from toluene and _C H ₂ C1 ₂ (1: 1% by volume). A red-brown crystalline compound with a decomposition point of ~ 255 ° C. is obtained. In CH ₂ C1 _{2 it has} an absorption maximum at 21. 10 ³ cm 1 in the UV range.

Example 3

A 20 x 100 x 2 mm thick commercially available glass mat-reinforced epoxy resin plate is activated according to Example 1, sensitized according to Example 2 and then copper-coated for 20 minutes in a commercially available copper plating bath. A continuously copper-plated plastic plate is obtained.

Example 4

enthält bei 30°C versetzt und 20 Minuten nachgerührt. Dann wird die wäßrige Phase von der organischen abgetrennt.15 g of aqueous Li ₂ PtCl ₆ solution (Pt content: 1.6% by weight) are mixed with 1 l of petroleum ether (technical), which additionally contains 2.7 g of crown ether of the formula

contains mixed at 30 ° C and stirred for 20 minutes. Then the aqueous phase is separated from the organic.

A dark-colored homogeneous activation solution is obtained. With this solution, an ABS plate with the dimensions 100 x 100 x 2 mm is treated for 5 minutes. The specimen thus activated is dried at RT, sensitized according to Example 2, and then nickel-plated according to Example 2. An electrically conductive metal pad is obtained.

Example 5

A 10 x 10 cm square of a knitted fabric made of a polyester-cotton blend is at RT for 20 seconds in an activation bath which consists of 2.9 g of crown ether of the formula

1 1 CH ₂ Cl ₂ and 1.0 g of hydrochloric acid KAuCl ₄ solution (Au content: 20% by weight) are prepared by stirring for 20 minutes, immersed and then without current in a commercially available nickel plating bath from Shipley AG, Stuttgart nickel plated. After a few seconds, the surface begins to turn shiny metallic. After 20 minutes, ~ 20 g metal / m ² deposited.

Example 6

besteht, im Verlaufe von 5 Minuten haftaktiviert, an der Luft getrocknet und dann in einem Sensibilisierungsbad bestehend ausA 200 x 100 x 2 mm thick, injection-molded plate made of an acrylonitrile / butadiene / syrene polymer is placed in an activation bath which consists of

consists, activated in the course of 5 minutes, air-dried and then consisting of in a sensitization bath

5 Minuten behandelt.

Treated for 5 minutes.

The activator adheres to the surface of the substrate so firmly that, despite subsequent treatment in a commercially available, concentrated NaOH solution (~ 45%), it is not possible to remove grease residues and mold release agents from the injection molded part.

The specimen activated in this way can then be provided with a well-adhering chemogalvanic metal coating according to Example 2.

Preparation of 1,4,7,10,13,16-hexaoxacyclooctadecane sodium tetrachloropalladinite

0.1 mol of Na ₂ PdC1 ₄ (anhydrous) are mixed with 5 l of pure CH ₂ C1 ₂ , which contains 0.2 mol of 1,4,7,10,13,16-hexaoxacyclooctadecane, and the mixture is subsequently stirred at the boiling temperature for 30 minutes and filtered off and then cooled. The solvent is removed from the organometallic compound under vacuum. The new compound is then recrystallized from purified 1,1,1-trichloroethane. A red-brown crystalline compound with a melting point of 223 ° C. is obtained. Your solution in CH ₂ C1 ₂ has an absorption maximum at 2 ₂ in the UV range. ₁₀ ³ cm ^-1 on.

Example 7

besteht, 5 Minuten aktiviert, nach Beispiel 2 sensibilisiert und dann nach Beispiel 2 auf dem chemischen Wege vernickelt bzw. galvanisch verstärkt. Man bekommt einen Polymer-Metall-Verbundwerkstoff mit guter Metallhaftung.A 200 x 100 x 3 mm thick, injection-molded, commercially available polyamide 6 plate is placed in an activation bath, which consists of

exists, activated for 5 minutes, sensitized according to Example 2 and then nickel-plated or galvanically amplified according to Example 2. You get a polymer-metal composite with good metal adhesion.

Preparation of 1,4,7,10,13,16-hexaoxacyclooctadecane-hexachloroplatinic acid

0.1 mol H ₂ PtCl ₆ are mixed with 8 1 CH ₂ C1 ₂ (post-cleaned), which contains 2 mol 1,4,7,10,13,16-hexaoxacyclooctadecane, stirred at 40 ° C for 30 minutes, filtered off and then the solvent is removed from the organometallic compound under vacuum. The new compound is then recrystallized from CH ₂ C1 ₂ and CC1 _{2 =} CC1 ₂ (1: 1% by volume). An orange-yellow compound with a decomposition point of 133 ° C. is obtained. In CH ₂ C1 ₂ it has an absorption maximum at 37 in the UV range. 10 ³ cm 1 on.

Example 8

besteht, 5 Minuten aktiviert, nach Beispiel 2 sensibilisiert und dann nach Beispiel 2 auf dem chemischen Wege vernickelt bzw. galvanisch verstärkt. Man erhält einen Polymer-Metall-Verbundwerkstoff mit guter Metallhaftung.A 200 x 100 x 3 mm thick polyamide-6,6 plate is placed in an activation bath

exists, activated for 5 minutes, sensitized according to Example 2 and then nickel-plated or galvanically amplified according to Example 2. A polymer-metal composite material with good metal adhesion is obtained.

Preparation of 1,4,7,10,13-pentaoxocyclododecane hexachloroplatinic acid

0.1 mol H ₂ PtCl ₆ are mixed with 8 1 CH ₂ CC1 ₂ (post-cleaned), which contains 0.2 mol 1,4,7,10,13,16-hexaoxacyclooctadecane, stirred at 40 ° C for 30 minutes, concentrated in vacuo to dryness and then recrystallized from CH ₂ C1 ₂ and toluene (1: 0.25% by volume). An orange compound with a decomposition point of 163 ° C. is obtained. In CH ₂ C1 _{2 it has} an absorption maximum at 42. 1 ₀ ³ _cm ¹ .

Example 9

A 10 x 10 cm knitted fabric made of a polyester-cotton blend is placed at RT for 60 seconds in an activation bath which consists of 0.01 mol guest-host molecule based on 0.01 mol 1,4,7,10,13 , 16-hexaoxacyclooctadecane and 0.01 mol HAuCl ₄ and an absorption maximum at 31. 10 ³ cm ^-1 in the UV range, dipped and then nickel-plated according to Example 5. After a few minutes, the surface begins to turn shiny metallic.

After 18 to 20 minutes, 20 g of metal / m ^{2 have} deposited. The yellow compound listed above has an unsharp melting point of 123 ° C.

Example 10

A 10 cm x 10 cm knitted fabric from a cotton fabric is at RT for 45 seconds in an activation bath, which consists of a guest / host molecule based on 0.005 mol 1,4,7,10,13-pentaoxacyclododecane and 0.005 mol HAuCl ₄ in CH ₃ CC1 ₃ consists, activated, dried and then copper-plated in a commercially available copper plating bath. In the course of approx. 15 minutes, a shiny, well-adhering and electrically conductive copper layer is deposited on the sample surface.

The complex compound used has an unsharp melting point at 97 ° C and a UV absorption maximum at ^{51. 103} cm ^-1 .

Claims (10)

1. A process for activating substrate surfaces for electroless wet chemical metallization with the aid of solutions of organometallic compounds based on elements of the 1st or 8th subgroup of the periodic table in aprotic solvents, characterized in that those with an "host / Guest "correlation used. 2. The method according to claim 1, characterized in that the complex-forming host molecules in the organometallic compounds are crown ethers, cryptands or podands. 3. The method according to claim 1, characterized in that the selective complex ligand or the host molecule in the organometallic compound is a cyclic compound which, in the presence of the medium to be complexed, assumes the structure required for complex formation or host / guest interaction. 4. The method according to claim 1, characterized in that the host molecules cyclic crown ethers of the formulas

R = alkyl or aryl; eg contain methyl, ethyl, phenyl, biphenyl, phenylazophenyl and others. 5. The method according to claim 1, characterized in that the selective complex ligand or the host molecule in the organometallic compounds have a pure hydrocarbon structure. 6. The method according to claim 1, characterized in that the host molecules of the organometallic compounds contain additional functional groups. 7. The method according to claim 1, characterized in that the medium to be complexed in the host / guest molecules is a compound of the formula

is, in which Me stands for hydrogen, alkali, alkaline earth or heavy metal atoms, or for NH ₄ , Hal for halogen, E for a noble metal atom of the 1st and 8th subgroup of the periodic table, with the valency m and the coordination number z, where zm = n. 8. The method according to claim 1, characterized in that the guest molecule to be complexed is a compound from the series H ₂ PdC1 ₄ , Na ₂ (PdCl ₂ Br ₂ ), Na2PdC14, Ca PdCl ₄ , Na ₄ (PtCl ₆ ), AgN0 ₃ and Is CuCl. 9. Organometallic compounds based on elements of the 1st or 8th subgroup of the periodic table with a "host / guest" interrelation. 10. Organometallic compounds according to claim 9, characterized in that the host molecules cyclic crown ethers, cryptands or podands and the inorganic part compounds of the formula

wherein Me for hydrogen, alkali or alkaline earth metal atoms or heavy metal atoms or for NH ₄ , Hal for halogen
and E represents a noble metal atom of the 1st or 8th subgroup of the periodic table with the valency m and the coordination number z, where zm = n,
are.