DE102015201562A1 - Method for metallizing plastic parts and solution - Google Patents

Abstract

The invention comprises a method for metallizing plastic parts with the steps pretreatment of the plastic surface, chemical metallization, wherein for pretreatment, the surface of the plastic part with at least one low-boiling organic liquid is dissolved and / or swollen, so then the loosened and / or swollen plastic surface by vaporizing the at least one low-boiling organic liquid is structured and so that the surface thus structured is hydrophilized without chromic acid-sulfuric acid solution.

Description

The present invention relates to a method for metallizing plastic parts with a special pre-treatment for producing a pre-structured plastic surface and solution for dissolving or swelling the surface of plastic parts for subsequent metallization.

For several decades, the metallic coating of plastics has been known by means of electroless (chemical) and galvanic processes.

• 1. Die Oberflächenstrukturierung des Kunststoffes. Durch die Struktur wird die Oberfläche vergrößert, entlang der Grenzfläche laufende Risse müssen daher größere Wege zurücklegen. Variationen im Spannungszustand durch die sich räumlich verändernde Lage der Grenzfläche führen dazu, dass Risse auf der Grenzfläche in das Kunststoffbauteil verlagert werden und damit die Bruchenergie vergrößern.
• 2. Die Benetzbarkeit der Oberfläche. Durch Ladungen induzierte anziehende Wechselwirkungen der Bauteiloberfläche mit Molekülen der Beschichtungslösung führt zu einer Abscheidung der Metalle im engen Kontakt zur Oberfläche, insbesondere in den Feinstrukturen der unter 1. hergestellten Oberflächenstrukturierung.

The adhesive strength of electroless or electroplated metallic layers on plastic surfaces is determined essentially by two factors:

• 1. The surface structuring of the plastic. Due to the structure, the surface is enlarged, along the interface running cracks must therefore cover larger paths. Variations in the state of stress due to the spatially varying position of the interface lead to cracks being displaced on the interface into the plastic component and thus increasing the fracture energy.
• 2. The wettability of the surface. Charge-induced attractive interactions of the component surface with molecules of the coating solution leads to a deposition of the metals in close contact with the surface, in particular in the fine structures of the surface structuring produced under 1.

• 1. Kunststoffe (Polymere) können je nach Aufbau unterschiedlich stark ausgeprägte kristalline Bereiche ausbilden. In diesen Bereichen sind die Makromoleküle, aus denen die Kunststoffe bestehen, besonders dicht und können einem oxidativen Angriff besser widerstehen.
• 2. Bei der Verarbeitung von Kunststoffen können Partikel beigemischt werden, die als Füllstoff die Materialeigenschaften lokal verändern.
• 3. Durch die Verwendung von polymeren Blends ( makroskopisch homogene Mischung von zwei oder mehr verschiedenen Polymeren, Def. nach IUPAC Compendium of Chemical Terminology 2nd Edition, 1997 ) werden gezielt Kunststoffe verwendet, die aus einer Mischung unterschiedlicher Kunststoffe bestehen.

According to the prior art, both factors are carried out by a selective oxidative attack of the surface, such as, for example, by means of chromosulfuric acid or potassium permanganate ( Suchentrunk, R et al., Plastics Metallization, Series Electroplating and Surface Treatment, 3rd Edition, Eugen Leuze Verlag, 2007 ). This process is also referred to as stain. For the electroless and galvanic coating of a plastic component, the following points must be considered:

• 1. Plastics (polymers) can form different degrees of crystalline areas depending on the structure. In these areas, the macromolecules that make up the plastics are particularly dense and can better withstand oxidative attack.
• 2. When processing plastics, it is possible to add particles that locally change the material properties as a filler.
• 3. By using polymeric blends ( macroscopically homogeneous mixture of two or more different polymers, Def. according to IUPAC Compendium of Chemical Terminology 2nd Edition, 1997 ) targeted plastics are used, which consist of a mixture of different plastics.

For example, plastics used to make metallic coated components almost always consist of different phases.

By using multiphase materials, the attack of the surface by the stain occurs locally at different speeds. This leads to a structuring of the surface ("structure etching").

The term "stain" is understood to mean a substance which dissolves parts of the plastic component surface in a non-reversible process. By breaking bonds of the macromolecules, the molecular chains are shortened and the strength of the material is reduced.

The selectivity of the pickling attack is limited in the known methods. Basically, all phases of the plastic are attacked, but at different speeds. In the case of readily miscible components, the easily etchable inclusions are not directly on the surface, so that the stain must first be used to attack the more stable component of the material directly on the surface.

The disadvantage of these methods is that the adhesion of a metal layer anchored in this way is limited by damage to the plastic component near the surface. In particular, fluctuations in the pickling attack have a relatively strong effect on the adhesion, since over-pickling leads to a sharp increase in the damage to the component and under-pickling causes too weak an expression of anchoring points.

Also known are substances that penetrate into the plastic (swelling), in some cases at sufficiently high concentration and exposure time can dissolve the material (solvent) and used before the structure-forming pickling process. In search trunk, R et al. For example, aqueous solutions containing one or more water-soluble substances, emulsions of water-insoluble substances, solutions of the swelling agents in non-aqueous solvents, and undiluted solvents are reported as systems that dissolve or swell plastic surfaces.

Examples of such substances are halogenated aliphatic hydrocarbons, aromatic hydrocarbons, ketones and also glycol ethers, ethyl acetate, dimethylformamide, dimethylsulfoxide, dioxane, turpentine oil, esters of carbonic acid and N- Mentions methylpyrrolidone. DE000004221948C1 discloses a process for the metallization of plastics in which the plastics are swollen by solvents before structuring in a potassium permanganate pickling solution. The task of the swelling agent is to intensify the subsequent pickling step. In addition, it is reported that roughening of the surface already takes place through the use of the solvents, which is intensified by the subsequent pickling process. Thus, the structuring is due to a selective dissolution of individual plastic components of a multi-phase mixture analogous to the subsequent etching process.

Search trunk, R et al. describe a method by which cracks are introduced into the surface of the plastic by a solvent, which is then used as a structure for anchoring a galvanically produced metallic layer. However, it is mentioned that due to the irregular distribution of the cracks thus produced in real components, a sufficiently reproducible layer quality with respect to the adhesion strength can not be produced.

A subsequent structuring of the surface by a phase transition of substances that penetrate into the component surface for anchoring of electrodeposited layers is not known in the literature.

The object of the invention is a process for producing prestructured plastic surfaces for the subsequent metallization, in which the pretreatment takes place without chromic acid-sulfuric acid solution.

The object is achieved by a method for metallizing plastic parts with the steps pretreatment of the plastic surface, chemical metallization, in which the surface of the plastic part with at least one low-boiling organic liquid is dissolved and / or swelled for pretreatment, then the loosened and / or swollen Plastic surface is structured by evaporation of at least one low-boiling organic liquid and the surface thus structured is hydrophilized without chromic acid-sulfuric acid solution.

Plastic surface refers to a surface of the plastic part used according to the invention. Plastics includes all polymer solids that are composed of polymerized organic monomeric molecules. Preferably, the plastic is a thermoplastic or thermosetting plastic. As plastics, it is possible to use all types of plastics which are suitable for coating with metals.

Preferably, the plastic part is an acrylonitrile-butadiene-styrene (ABS) plastic part or acrylonitrile-butadiene-styrene-polycarbonate (ABS / PC) plastic part.

ABS is a thermoplastic terpolymer composed of the three monomers acrylonitrile, 1,3-butadiene and styrene. ABS / PC is a blend of acrylonitrile, 1,3-butadiene, styrene and polycarbonate. The person skilled in the art is aware of the various types / compositions of ABS and ABS / PC plastics and their various properties, as well as the resulting possible uses.

Optionally, the plastic part contains at least one additive selected from plasticizers, flame retardants, fillers and light stabilizers. The person skilled in the various plastic additives are known.

The plastic part may be of any shape and size.

The surface of the plastic designates regardless of the size and shape of the plastic whose three-dimensional boundary surface.

For pretreatment, the surface of the plastic part is dissolved with at least one low-boiling organic liquid and / or swelled. Low-boiling liquids have at normal pressure (1.013 bar) a phase transition from liquid to gaseous at a temperature <100 ° C and can thus be easily removed by evaporation or evaporation from the plastic part.

Preferably, the at least one organic liquid has a boiling point of 2 to 100 ° C, more preferably from 2 to 90 ° C, most preferably from 2 to 70 ° C.

If the substance used as the at least one organic liquid is gaseous at normal temperature (25 ° C.), then the process must be carried out at correspondingly reduced temperatures. The process temperature must always be below the boiling point of the organic liquid, so that it is actually in the liquid state. The person skilled in methods for cooling substances are known.

Preferably, the at least one organic liquid is selected from acetone, methanol, ethanol, chloroform, dichloromethane, neopentane, 2,2-diethylpropane and a mixture of the at least one organic liquids with water.

The invention therefore also includes a solution for solving and / or swelling the Surface of plastic parts for subsequent metallization containing at least one low-boiling organic liquid selected from acetone, methanol, ethanol, chloroform, dichloromethane, neopentane (2,2-dimethylpropane) and a mixture of the at least one organic liquids with water.

The proportion of all low-boiling organic liquids in the mixture of low-boiling liquid and water is preferably 30 to 90% by volume, particularly preferably 40 to 70% by volume, very particularly preferably 45 to 65% by volume, measured on the total volume the mixture.

For the dissolution and / or swelling of the plastic part, preference is given to using a liquid mixture comprising at least one low-boiling organic liquid, water and at least one further ingredient. The at least one further ingredient advantageously improves, for example, the solution, dispersion and / or diffusion behavior of the at least one organic liquid.

Preferably, the proportion of all low-boiling organic liquids in the liquid mixture, comprising at least one low-boiling liquid, water and at least one further ingredient 2 to 60 vol .-%, particularly preferably 5 to 40 vol .-%, most preferably 10 to 25 vol .-%, measured on the total volume of the liquid mixture.

Preferably, the proportion of all other ingredients in the liquid mixture, comprising at least one low-boiling liquid, water and at least one further ingredient 5 to 70 vol .-%, more preferably 10 to 50 vol .-%, most preferably 20 to 50 vol. %, measured on the total volume of the liquid mixture.

Preferably, the at least one further ingredient selected from dimethyl sulfoxide (DMSO), acetic acid, N-methylpyrrolidone (NMP) and urea.

For example, the normally low solubility of DCM in water (20 g / L at 20 ° C) can be increased by the addition of DMSO, acetic acid and / or urea. The at least one further ingredient serves in this case as a solubilizer. The skilled person is aware of the ratio in which he must dose the additional ingredient to the liquid mixture in order to achieve its advantageous effect.

The invention therefore also includes a liquid mixture for dissolving and / or swelling the surface of plastic parts for the subsequent metallization, comprising at least one low-boiling organic liquid, water and at least one further ingredient selected from dimethyl sulfoxide (DMSO), acetic acid, N-methylpyrrolidone ( NMP) and urea.

Dissolving and / or swelling referred to in the context of the invention that the plastic part below the boiling point of the organic liquid or an organic liquid in a mixture of several liquids comes into contact with this or is contacted with this. Preferably, the plastic part is placed in the liquid, so that the plastic part is wetted by this. The amount of organic liquid depends on the size of the plastic part. Preferably, the plastic part should be completely in the liquid, so that no area of the plastic part is above the liquid level. The specialist will select a suitable vessel for the liquid. Advantageously, this is not attacked by the liquid.

Preferably, the plastic is contacted with the liquid for 30 seconds to 30 minutes, more preferably for 2 to 20 minutes, most preferably for 3 to 8 minutes.

When dissolved and / or swelled, the organic liquid penetrates into the surface of the plastic of the plastic part. The depth of penetration depends on how long the plastic part is contacted with the organic liquid.

Preferably, the organic liquid penetrates 0.5 to 50 microns, more preferably 0.5 to 20 microns, most preferably 1 to 10 microns deep in the plastic surface.

The organic liquid dissolves the areas of the plastic and / or on, which are soluble for the respective solvent. In addition, there is partial swelling of the plastic areas in which the liquid is present.

In a particular embodiment of the invention, the plastic part is cleaned before contacting with the organic liquid. The person skilled in methods for cleaning plastic surfaces are known. For example, an ABS plastic can be degreased with an alkaline, wetting agent-containing solution.

After dissolution and / or swelling, the plastic part is removed from the liquid.

Subsequently, the loosened and / or swollen plastic surface of the plastic part is structured by evaporating the at least one low-boiling organic liquid. Advantageously, the evaporation is carried out by heating the plastic part, for example by means of microwave and / or by immersion in a tempered bath, with a temperature of at least 5 K above the boiling point of the lowest-boiling organic liquid of at least one organic liquid. Preferably, the tempered bath is a water bath. By heating the liquid still contained in the dissolved and / or swollen plastic surface, this undergoes a phase transition from liquid to gaseous. The heating must be rapid, so that the phase transition and the associated gas bubble formation a pressure in the plastic part surface is generated, which leads to a deformation of the surface, whereby it is structured.

The temperature-controlled bath preferably has a temperature of from 20 to 100.degree. C., particularly preferably from 40 to 80.degree. C., very particularly preferably from 50 to 70.degree.

It is advantageous to keep the tempered bath at the desired temperature with the aid of a suitable device, so that the bath has the same temperature during the entire time of contacting.

As a result of the contact with the tempered bath, the low-boiling organic liquid still adhering to and / or adhering to the plastic surface changes from the liquid to the gaseous state and is thus removed from the plastic. Surprisingly, it has been found that pores are formed during the transition of the liquid into the gaseous state by a local volume expansion in and / or on the plastic surface, through which the plastic surface receives a structuring. So far, it has not been known that liquids which can lead to the (dissolving) / swelling of areas of the plastic by a change in the state of aggregation of the solvent for structuring the same. By using a liquid mixture comprising at least one low-boiling organic liquid, water and at least one further ingredient, the structuring is additionally enhanced. When the plastic part is heated, the lowest-boiling liquid first passes into the gaseous state.

Preferably, the plastic part for 1 to 120 s, more preferably for 5 to 60 s, most preferably for 9 to 30 s, heated.

Advantageously, the plastic is contacted with the tempered bath until the low-boiling organic liquid has been almost completely removed from the plastic.

The organic liquid can both emerge from the tempered bath and / or dissolve in the bath. If the organic liquid in the gaseous state, so the expert will take precautions (eg work in the fume cupboard, installation of a suction system), so that they do not spread uncontrollably in the ambient air.

Subsequently, the structured plastic part is removed from the temperature-controlled bath.

The thus structured plastic surface of the plastic part is then hydrophilized, so that the hydrophobic structured plastic surface receives hydrophilic properties. The hydrophilization can be carried out, for example, by breaking existing double bonds in the plastic by plasma treatment, flaming or chemically by oxidation by means of a hydrophilizing bath in a known manner. The person skilled in suitable methods for hydrophilizing the various plastics are known.

According to a particular embodiment of the method according to the invention can be dispensed with the hydrophilization, if the plastic part consists of a plastic, which already has sufficient hydrophilic properties for metallization.

According to an advantageous embodiment of the method according to the invention, the evaporation of at least one low-boiling liquid from the plastic part and the hydrophilization of the plastic part takes place in one process step. For this purpose, a tempered Hydrophilierungsbad, having a hydrophilicizing additive and a temperature of at least 5 K above the boiling point of the lowest-boiling organic liquid of at least one organic liquid.

The hydrophilicizing additive is preferably selected from oxygen acids of sulfur, persulfates, peroxides and hypochlorides.

It is particularly advantageous according to the process of the invention that no toxic chromic acid-sulfuric acid solutions are required for the hydrophilization.

The metallization of the plastic parts pretreated according to the invention takes place in a known manner, e.g. by applying a catalyst and subsequent electroless deposition of a metal layer of a metal compounds containing solution, as described in Example 1.

Surprisingly, it has been found that the plastic parts structured according to the invention have the same or even improved adhesive properties for the metal compared to metallizations according to the prior art.

To analyze the adhesion, a so-called Andreas cross test can be performed. In this case, two intersecting cuts are introduced through the metallic coating with a cutter knife. Then an adhesive strip is glued on and quickly peeled off. If the coating is not removed during this test, good adhesion is achieved.

A more precise determination of the adhesive strength can be made by a peel test: After preparation of a 1 cm wide strip with cutter knife through the metallic coating of the strip thus obtained is withdrawn at 90 degrees at a rate of 50 mm per minute. Measured is the force required for the trigger.

Application-related testing of components may be performed by a climate change test (e.g., Volkswagen PV 1200). The component is cyclically heated and cooled several times. Due to the different expansion coefficients of plastic and metal, mechanical stresses develop at the interface. After loading, no visible defects on the component may occur.

A typical, exemplary procedure of the metallization by electrodeposition of copper on plastic components consists of the application of a catalyst (preferably palladium), a subsequent electroless deposition of nickel in a nickelsalzhaltigen bath and the subsequent electrodeposition of copper in a copper electrolyte. If the structured and hydrophilized components according to the invention are coated with copper in this way, surprisingly, a particularly high adhesive strength of the layers can be ascertained.

embodiments

Based on the following illustrations and embodiments, the invention will be explained in more detail without limiting it to these. Show

1 Scanning electron micrograph of a structured ABS plastic according to embodiment 1

2 Scanning electron micrograph of a structured ABS plastic according to exemplary embodiment 2

3 Scanning electron micrograph of a structured ABS plastic according to exemplary embodiment 3

4 Scanning electron micrograph of a structured ABS plastic according to Embodiment 4, in which the plastic was treated with a DCM solution and tempered at 25 ° C.

5 Scanning electron micrograph of a structured ABS plastic according to Embodiment 4, in which the plastic was treated with a DCM solution and tempered at 70 ° C.

6 Scanning electron micrograph of a structured ABS plastic according to Embodiment 4, in which the plastic was treated with a DMSO solution and tempered at 70 ° C.

7 Scanning electron micrograph of a structured ABS plastic according to Embodiment 4, in which the plastic was treated with a DMSO solution and tempered at 25 ° C.

8th Force-displacement diagram of the peel test.

example 1

From a ABS plastic plate (Maywoflamm 1651 ABS UL 94 VO, thickness 1.5 mm), a sample with dimensions of 12 mm × 100 mm is cut out and cleaned for 5 min in an ultrasonic bath in 96% denatured alcohol. 50 ml of acetone are made up to 100 ml with water and the sample is incubated for 10 minutes at room temperature in this solution. The sample is then removed from the solution and immersed immediately for 10 seconds in water at a temperature of 97 ° C. The escape of the gaseous acetone from the sample can be detected by the formation of gas bubbles on the surface of the sample. Subsequently, the sample is first coarse dried with compressed air and after-dried over 12 hours.

For analysis of the surface structure, a portion of the sample was cut off, vapor-deposited with gold and examined in a scanning electron microscope ( 1 ). The surface has a dense distribution of pores with a diameter less than 2 microns. It can be clearly seen that the pores are present individually and have small elevations at the edges. The bright exuberance at the pore edges also indicates a greater extent of the pore in the component. The over-radiation is caused by thin-walled areas, where it is stronger in the electron microscope electrostatic charge comes. These features indicate that the pores are not formed by material discharge via a pure diffusion but by gas bubbles which are brought to the surface and which are caused by the rapid phase transition of the solvent.

In order to increase the wetting of the surface for the subsequent steps, the sample is then treated for 30 seconds in oxygen plasma at a pressure of 0.4 mbar (Zepto plasma chamber from Diener electronic GmbH + Co. KG., Plasma-Surface-Technology). This is followed by a multi-stage process of metal coating, which consists of the following process steps:

Precious metal / nickel

3 min incubation in pretreatment solution (350 ml deionized water and 400 ml of 37% hydrochloric acid)
4 min incubation in activator (Enthone activator Udique 879 W) at 32.5 ° C
2x rinse with deionized water
3 min incubation in accelerator (Enthone Udique 8810) at 37 ° C
2x rinse with deionized water
5 min incubation in nickel at 33 ° C with low stirring power
2x rinse with deionized water
treat with compressed air

Vorkupfer

Galvanic coating of the sample with pyro-copper solution (Atotech Pyrolume CU) at 50 ° C and 0.5 A / dm2 for 30 seconds, 1.0 A / dm2 for 30 seconds and 2.0 A / dm ² for 9 minutes
Rinse in demineralised water
Blow off with compressed air

bright copper

Galvanic coating at room temperature in acidic copper solution (Atotech Cupracid 210) and 5 A / dm2 for 44 minutes
Rinse with deionised water
Blow off with compressed air
Dry the sample for at least 1 hour in a drying oven at 70 ° C
To check the adhesion, a 1 cm wide strip of the metal coating was cut longitudinally through two sections with a cutter. The metal strip thus exposed was peeled off from a sample side at an angle of 90 ° C at a rate of 50 mm per minute in a peel tester (MultiTest 2.5-i from Mecmesin) and the force was recorded along the process path. The average peel force reaches a value of approx. 20 N ( 8th ).

Example 2

As Example 1, but after cleaning the sample for 6 min incubation in a solution prepared by filling 65 ml of acetone with deionized water to 100 ml. Subsequently, the sample is immersed for 10 seconds in deionized water at a temperature of 65 ° C. The SEM image ( 2 ) shows a dense distribution of pores less than 2 microns as in Example 1. The picture has similarities 1 but, due to the more intensive solvent attack, a stronger deformation of the entire surface takes place.

For analysis of the surface structure, a portion of the sample was cut off, vapor-deposited with gold and examined in a scanning electron microscope ( 2 ). The surface has a dense distribution of pores with a diameter less than 2 microns. It can be clearly seen that the pores are present individually and have small elevations at the edges. The bright radiance of the pore edges also indicates a greater expansion of the pores in the component. The overexposure is caused by thin-walled areas, where a stronger electrostatic charge occurs in the electron microscope. These features indicate that the pores are not formed by material discharge via a pure diffusion but by gas bubbles which are brought to the surface and which are caused by the rapid phase transition of the solvent.

Example 3

Like Embodiment 1, but after incubation, the sample is immersed in deionized water at a temperature of 65 ° C for 10 seconds. For analysis of the surface structure, a portion of the sample was cut off, vapor-deposited with gold and examined in a scanning electron microscope ( 3 ). The SEM image shows a surface which, in contrast to exemplary embodiments 1 and 2, has hardly any pores. Since no structuring by pores on the scale of one micrometer and less occurs despite the identical treatment by solvent, it has been shown that the temperature control of the sample following incubation in the solution is a necessary prerequisite for the structuring of the sample.

Example 4 - Pretreatment with a liquid mixture

From an ABS plastic plate (Maywoflamm 1651 ABS UL 94 VO, thickness 1.5 mm), a sample with dimensions of 12 mm × 100 mm is cut out and for 5 min in 96% denatured alcohol cleaned. The thus cleaned plastic plate is immersed in a solution of DCM, water and DMSO.

Make a dichloromethane solution

18.8 ml of dichloromethane (DCM) are added to 231 ml of water. The resulting mixture is stirred with magnetic stirrer at 300 rpm. then 80 ml of dimethyl sulfoxide (DMSO) are added and stirred for a further 2 h. The remaining dichloromethane phase is separated by centrifugation at 5000xg / 10 min and decanting from the solution. A solution of water, DMSO and DCM (saturated) is obtained, hereinafter referred to as DCM solution.

As a reference, an identical solution was prepared but without the addition of DCM. It is hereinafter referred to as DMSO solution.

Pretreatment of the plastic

Two "plating grade" acrylonitrile-butadiene-styrene samples (hereinafter ABS samples) are immersed in the DCM solution for 10 min.

At the end of the incubation period, a sample is immersed directly in water at 25 ° C for 10 seconds and the other sample in water at 70 ° C for 10 seconds.

Two more ABS samples are treated identically, but the DMSO solution is used instead of the DCM solution.

Analysis of the surface structure

All four ABS samples are analyzed by Scanning Electron Microscope (SEM) with the following parameters:
Steaming with gold
Acceleration voltage 10 kV
Detector SE
Magnification 10000x

In the SEM images, only in the sample produced according to the invention (incubation in DCM solution, immersion in water of temperature 70 ° C.) a significant structuring of the surface is discernible ( 5 ). A "stain" visible with the naked eye, as in the classical treatment with acids, is not recognizable in all samples. On the other hand, the scanning electron micrograph shows marked differences on the sample surface. While in 4 (Treatment with DCM solution and incubation at 25 ° C) isolated larger pores can be seen, but which at their edges neither a pronounced formation of surveys, nor in their overwhelming number of radiations, can on a structuring in the known manner be closed by selective solvent attack.

In 5 is in analogy to 1 a fine structure of pores visible, as in 1 described due to the formation of gas bubbles.

Omitting the low boiling component in 6 (Treatment with DMSO solution and incubation at 70 ° C) and 7 (Treatment with DMSO solution and incubation at 25 ° C) results in comparison to 4 to even less structuring without the characteristics of gas bubble formation.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 000004221948 C1 [0011]

Cited non-patent literature

• Suchentrunk, R et al., Plastics Metallization, Series Electroplating and Surface Treatment, 3rd Edition, Eugen Leuze Verlag, 2007 [0004]
• macroscopically homogeneous mixture of two or more different polymers, Def. according to IUPAC Compendium of Chemical Terminology 2nd Edition, 1997 [0004]

Claims (8)

A process for the metallization of plastic parts comprising the steps of pretreatment of the plastic surface, chemical metallization, characterized in that is for the pre-dissolved the surface of the plastic part with at least one low boiling organic liquid and / or swollen in that subsequently the partially dissolved and / or swollen plastic surface by Vaporization of the at least one low-boiling organic liquid is structured and that the surface thus structured is hydrophilized without chromic acid-sulfuric acid solution. A method according to claim 1, characterized in that the plastic part is an acrylonitrile-butadiene-styrene (ABS) plastic part or an acrylonitrile-butadiene-styrene-polycarbonate (ABS / PC) plastic part. Method according to one of claims 1 or 2, characterized in that the at least one low-boiling organic liquid has a boiling point of 2 to 100 ° C. Method according to one of claims 1 to 3, characterized in that for evaporating the at least one low-boiling liquid, the plastic part is heated. A method according to any one of claims 1 to 4, characterized in that the evaporation by immersing the plastic part in a temperature-controlled bath, with a temperature of at least 5 K above the boiling point of the lowest boiling organic liquid of at least one organic liquid is carried out. Method according to one of claims 1 to 5, characterized in that the evaporation of the at least one low-boiling liquid from the plastic part and the hydrophilization of the plastic part takes place in one process step. Solution for dissolving and / or swelling the surface of plastic parts for the subsequent metallization, comprising at least one low-boiling organic liquid selected from acetone, methanol, ethanol, chloroform, dichloromethane, neopentane and a mixture of the at least one organic liquids with water. Liquid mixture for dissolving and / or swelling the surface of plastic parts for the subsequent metallization, comprising, at least one low-boiling organic liquid, water and at least one further ingredient selected from dimethyl sulfoxide (DMSO), acetic acid, N-methylpyrrolidone and urea.

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