DE102008048459A1 - Producing conductive structures on surface of polymer molded bodies, comprises providing polymer molded body from a polymer phase containing carbon nanotubes and thermally treating a surface of the polymer molded body - Google Patents

Abstract

Producing conductive structures on the surface of no or only slightly conductive polymer molded bodies, comprises: (a) providing a polymer molded body from at least one polymer phase containing carbon nanotubes; and (b) thermally treating at least one surface of the polymer molded body to produce the conductive structures on the surface of the polymer molded body, where the thermal treatment comprises heating at a temperature, which corresponds to at least the melting temperature of at least one polymer phase. Independent claims are included for: (1) the polymer molded body with conductive structures on the surface, produced by the above process, preferably comprising at least one polymer phase with carbon nanotubes, where the polymer molded body exhibits electrically or thermally conductive structure on the surface and the concentration of carbon nanotubes in the area of the electrically conductive surface structure is higher than in the non-electrically conductive surface area, and the non-electrically conductive surface area contains carbon nanotubes; (2) a printed circuit board-arrangement comprising at least one printed circuit board, which is preferably a polymer molded body, with at least one electrically conductive trace pitch, where the printed circuit board contains the polymer molded body with 0.1-10 wt.% of carbon nanotubes, relative to the mass of the polymer phase, and at least one electrically conductive trace pitch comprises a metal layer, preferably a copper layer, and/or at least one electronic component, which is bonded by an organic adhesive composition comprising 0.05-10 wt.% of carbon nanotubes, relative to the mass of the adhesive composition, and/or by a bond comprising the carbon nanotubes containing material, preferably one or more carbon nanotubes containing polymer phases, and/or by a solder connection with at least one electrically conductive trace pitch of the printed circuit board; (3) a process for producing the printed circuit board arrangement, comprising the steps (a) and (b), (c) galvanizing the electrically conductive structure with a metal, preferably copper, and/or (d) providing at least one electronic component, and (e) connecting, preferably thermally and/or electrically conductive connections, the electronic component having at least one electrically conductive trace pitch or at least an electrically conductive area using the adhesive composition, by producing a bond and/or by a solder connection; (4) use of an adhesive composition comprising carbon nanotubes for electrically conductive connecting of an electronic component with another electrically conductive component or molded part, preferably an electrically conductive trace pitch or an electrically conductive area on a trace pitch; and (5) use of a device for producing conductive structures on the surface of a polymer molded body of at least one polymer phase, where the device has an energy source with at least one electrode, which is provided to lose an energy with which the body to be processed is at least partially heated.

Description

The The invention relates to a device for producing a structure on a body to be processed according to the Preamble of claim 1 and in particular a device for producing an electronic circuit on a polymer molding of at least one polymer phase containing carbon nanotubes. The invention further relates to a device for generating a Structure on a body to be machined with the one to be worked on Body and the device according to the Invention and a plotter with the device, a matrix printer with the device and a stylus with the device. Further The invention relates to a method for producing a structure on a body to be worked according to the The preamble of claim 14.

electronic Circuits are usually made by applying a copper layer produced on a substrate, taking care of the circuit unneeded parts of the copper layer by chemical Processes are etched away. The production of such circuits is usually very complex and involves many process steps.

In contrast, The present invention is based on the object, a device for creating a structure on a body to be processed to provide according to the preamble of claim 1, with the number of method steps for generating the structure can be reduced.

Based on the printed circuit board, the present invention is based on the idea Do not get the needed material for the first Applying structure on a substrate and then the wegzuätzen not needed material, but the Structure like drawing an image directly with a suitable one Apply device.

Therefore the invention proposes a device for generating a Structure on a body to be processed with an energy source in front. The energy source has at least one electrode, via the energy can be given off. This released energy heats up at least partially the body to be processed. By The body can heat at defined points specifically heated and thereby chemically altered, whereby the structure to be generated on the body to be processed directly applicable. This eliminates the step, first Apply a layer of material on a substrate, and then to Forming the structure partially wegzuätzen the material layer.

The Invention is particularly suitable when the body is a polymer molding is at least one polymer phase containing carbon nanotubes, there in this body by applying an energy to very specific Positions the conductivity are changed can. Thus, tracks can be processed on one Body without application of a conductive material layer and then erasing the unneeded Create areas of the conductive material layer. On this way work steps are saved, the production of the Ladder plate speeds up and thus the profitability of the production elevated.

Of the The body to be processed is particularly effective generate if the energy source has at least two electrodes, which can be applied to the body to be processed, wherein with the two electrodes a current through the body to be processed is conductive or a voltage can be applied, the to be processed Body warms up and, as further below described, preferably in defined ranges z. B. at the Surface melted. Through this simple technical Measure can be taken on the body to be processed according to a possible embodiment also three-dimensional Create structures, as the two electrodes, for example, on the front and at the back of the machined Body can be applied. For example, it can be opened like this easy way holes in the body to be processed burn in or, in the case of the printed circuit board described above, Establish contacts between two levels. Thus can be inexpensive with the device of the present invention Produce multilayer printed circuit boards.

For producing simple strip conductors in a plane of the body to be processed, one electrode of the energy source can be fixed at one point, wherein the other electrode is arbitrarily moved on the body, whereby in particular in the case of a printed circuit board, the electrical conductor tracks are generated. Alternatively, however, both or more electrodes can be moved simultaneously. According to a further embodiment of the invention, the two electrodes can also be held with a spacer at a predetermined distance from each other, so that both electrodes are moved together over the body to be processed in the formation of the structure. The electrodes or the polymer molding facing parts thereof, for. B. in stick form, may in principle have any shape, wherein the shape of the shape of the desired conductor tracks to be generated by the skilled person freely selectable is. The applied voltage or the current can also be chosen freely, it being possible for the person skilled in the art, depending on the polymer molding used, its composition and the degree and range of the desired heating of the molding material, to determine empirically the suitable values. In many cases, for. B. be a voltage of more than 500 V, in particular of 1000 V or more favorable.

To a preferred embodiment of the invention becomes a first electrode in a first region of the polymer molding (or its surface) on the already a conductivity exists or created, while a second Electrode starting from a point on the polymer molding (or its surface), in the same conductive Range, or with this area via a conductive Area (such as a track) is connected via the Polymer molding (or its surface) moves, to create a (new) trace, the conductive Enlarge area or two existing conductive ones To connect areas (eg tracks). This approach allows a great deal of flexibility the generation or design of the conductive structures on the polymer molding.

The Apparatus according to the present invention may be particularly effective according to one possible embodiment built into a plotter, matrix printer or pen become. In a method for creating a structure on a The body to be processed becomes the body to be processed by an energy source having at least one electrode leading to Delivering an energy is provided, at least partially heated.

In the method according to the invention can be apply the aforementioned device characteristics with the same effect.

The Invention will be described below with reference to two non-limiting Embodiments described in more detail. In the Drawings show:

1 a device with a device according to a first embodiment of the present invention;

2 a device with a device according to a second embodiment of the invention;

3 the device according to the second embodiment of the invention; and

4 the device according to the first embodiment of the invention.

In the figures use the following reference numerals:

10

device

12 14

pencils

16 18

Contact pen

20 22

Contact plug

24

plug

26

polymer body

28

conductor path

30

surrounding area

32

drawn lines

34

contact point

36

bottom

38

device

40

pen

42

heating coil

44

protective body

46

plug

In a first embodiment of the invention, which in the 1 and 4 shown points the device 10 a first pen 12 and a second pen 14 on. Both pins each have a contact on their underside 16 . 18 on, each with a contact 20 . 22 a plug 24 are electrically connected.

When creating the contacts 16 . 18 of the pens 12 . 14 to a polymer body 26 from at least one polymer phase with carbon nanotubes can be when the contacts 16 . 18 of the pens 12 . 14 spaced apart and a current through the polymer body 26 lead, the polymer body 26 to heat specifically. By targeted heating of the polymer body 26 can be on this tracks 28 muster up the electricity from the contacts 16 . 18 of the pens 12 . 14 can also lead. For example, becomes the first pen 12 with the first contact 20 firmly fixed at one position and only the second pin 14 with the second contact 18 moved on the circuit board, so is the distance between the already created trace and the current position of the second contact 18 very low depending on the speed of movement. From this small distance follows a low resistance between the conductor track 28 and the second contact 18 , causing the conductor track 26 in a surrounding area 30 for the second contact 18 of the second pen 14 is heated, and so the trace 28 continues.

In a practical way, according to a possible embodiment, the printed conductors to be produced on the polymer body 26 with marked lines 32 be hinted to assist the manufacturing process of the circuit board. Further, on the polymer body 26 contact points 34 are prepared, which the polymer body 26 penetrate. All you need is the second pin 12 from the polymer body 26 be removed, and at the bottom 36 of the polymer body 26 approximately below the already created trace 28 be attached. This will turn over the track again 28 a current between the two contacts 16 . 18 the two pins 12 . 14 headed the contact point 34 through the polymer body 26 generated.

In the 2 and 3 a device according to a second embodiment of the invention is shown. After that, the device includes 38 a pen 40 , on the underside of which is a heating spiral 42 followed. This heating coil is preferably of a protective body 44 surround. The protective body may be provided to regulate the heating, or else to the heating coil 42 to protect against contamination or other external influences. Next points the device 38 according to the second embodiment of the invention, a plug 46 on, with the heating coil 42 can be supplied with electrical energy.

In use is the device 38 as shown in the first embodiment, over the pre-drawn lines 32 pulled, so that the already discussed interconnects 28 arise. In the present embodiment, it is not necessary to have a first pin at a predetermined location of the polymer body 26 to position.

With The invention can be easily structures on a Create body without it applying a base material and removing the unneeded locations of the base material needed. As a result, process steps are saved in the production, so that the production of the body to be worked more economically becomes. Accordingly, another aspect of the present invention relates the use of the devices, devices described above and methods for producing (conductive) structures Polymer moldings, in particular polymer moldings as described in more detail below.

The provide the above devices, devices and methods while special advantages in the use of the following invention Polymer moldings with conductive structures on the surface, including methods for its preparation to be discribed.

The The present invention accordingly relates to a further aspect a polymer molding with conductive, in particular electrically conductive, structures on the surface, and a method for producing these polymer molded bodies.

Electrically conductive plastics have long been known. US 4,404,125 describes the production of such plastics by admixing carbon fibers, optionally together with conductive carbon blacks, into a thermoplastic. In US 4,664,971 In place of the carbon fibers, electrically conductive metal fibers are used. In all these plastic mixtures, large amounts of electrically conductive additives are required, which are usually in a range of 10-30 wt .-%. Nevertheless, the electrical conductivity of these plastics, especially on the surface, is not yet sufficient for many technical applications.

WO 02/19346 describes the use of metal-coated carbon fibers for the production of electrically conductive plastics. This z. As a high-energy laser used to evaporate the plastic located on the surface and expose the underlying layers of electrically conductive additives. One disadvantage is the frequently occurring conductivity over the entire volume of the Kunststof Also, transversely to and beyond the laser-treated web, and the resulting problems in the arrangement of adjacent tracks.

Another method for producing electrically conductive structures on any substrate materials is disclosed in U.S. Patent Nos. 4,767,859 DD 263 179 described, wherein the substrate materials coated with an electrically conductive additive and crosslinking initiators containing prepolymer, the prepolymer selectively crosslinked by the action of high-energy radiation and the non-crosslinked portions of the plastic mixture with the aid of suitable solvents are removed. This method is very complex and associated with significant problems with respect to a sufficient adhesion of the structures on the substrate surface.

The DE 102 59 498 describes electrically conductive thermoplastics in which carbon nanotubes (CNT) are used in addition to particulate carbon modifications such as carbon black or graphite. By adding such carbon modifications, the electrical conductivity compared to metal fibers can be realized even with small amounts added. The electrical conductivity is distributed more or less evenly over the entire plastic volume and the surface. The electrical conductivity usually occurs only above a certain minimum addition of electrically conductive additives. Below this concentration, the conductivity is almost at the initial level of the non-conductive plastics. The limit from which conductivity is observed depends essentially on the plastic itself, the added filler or the added filler mixture and on the mixing and processing conditions to which the plastic mixture has been subjected.

Around To achieve a good electrical conductivity are at All these procedures require sufficient amounts of additives and the conductivity is largely uniform across the volume of the plastic molding distributed. With the rising Filling degree is but usually a deterioration of associated with mechanical properties, so at high fill levels for example, toughness and tensile and tear strength are significantly reduced.

Another possibility for producing electrically conductive structures on surfaces was T. Dekker (Carbon Nanotubes as Molecular Quantum Wires, Physics Today, pp. 22-28, 1999) described. Carbon nanotubes from the gas phase are deposited on a substrate. This method is also associated with a high technical complexity.

A The object of the present invention was therefore the known methods for the production of conductive structures on polymer moldings to simplify and improve and in particular polymer moldings to provide with particularly good properties.

The The object described above is achieved by the shaped polymer bodies defined herein and solved the process for their preparation.

in the The scope of the present invention has been surprisingly found that the partial melting of the surface a polymer molding containing carbon nanotubes, to a migration of the CNT to the surface of the polymer molding leads. By targeted melting of the surface in defined areas, it is thus possible in an advantageous manner to increase the concentration of CNT in these areas and the electrical and thermal conductivity of these Increase areas. A proof of the higher Concentration of CNT in the electrically conductive (thermal treated) areas may z. B. on light microscopic or electron micrographs. in this connection appear, for example, in a polymer molding Polycarbonate and CNT in the light microscope, the sites with high CNT density in black color, whereas those with low CNT density are white.

In contrast, it has surprisingly been found in the context of the present invention that the use of polymer moldings with other electrically conductive additives does not lead to a migration of the conductive substances to the surface. For example, the melting of polymer moldings with conductive fiber systems, such as. Aluflakes (manufacturer Alufllakes of the company Silverline, GB, used polymer blend polycarbonate / polypropylene, see example) or steel fibers does not lead to a migration of the conductive fibers to the surface. In these polymer moldings, therefore, only the method described above is made WO 02/19346 applicable. In the process of the invention, however, advantageously no evaporation of the polymer on the surface of the polymer molding is necessary.

In the method according to the invention, the rate of migration of both the Viskosi the polymer phases through which the CNT must move, as well as the respective compatibility of the surfaces of the CNT and the polymer phases, and the treatment time, ie the time available to the CNT, to the surface through the molten polymer to penetrate, depending. The longer the melting, the better the CNT can move to the surface, and the better the increase in electrical conductivity in the thermally treated areas.

Of Furthermore, it was surprisingly found that by stretching or bending the polymer molding of the Surface resistance of the same changes. Especially the surface resistance becomes greater the more the polymer molding is stretched. this makes possible the application of the polymer molding according to the invention in strain gauges.

The The present invention therefore relates in one aspect to polymer moldings with conductive, in particular electrically conductive, Structures on the surface, as well as a method for Production of these polymer moldings.

One Polymer molding in the context of the present invention an arbitrarily shaped three-dimensional body or a Polymer layer of one or more different polymers, the following both for the inventive Process as well as for the invention Polymer moldings are described.

According to the invention suitable Polymers are thermoplastics, thermosets, elastomers and inorganic Polymers and mixtures thereof, are preferred thermoplastics and Thermosets used. Preferred polymers are polycarbonate, acrylonitrile-butadiene-styrene (ABS), polyamides such as polyamide 6 (PA 6), polyamide 6.6 (PA 6.6), polyamide 6.4 (PA 6.4)), polyamide 12 (PA 12), aromatic polyamide, polyvinyl chloride, Nylon 6,6, polyvinyl fluoride, polyvinylidene fluoride, polyphenylene ether, Polystyrene, polyolefins such as polypropylene or polyethylene, polysulfone, thermoplastic polyurethane, polyethylene terephthalate, polybutylene terephthalate, thermoplastic elastomer alloys, acetal, styrene-maleic anhydride, Butadiene-styrene, polyetheretherketone, polyethersulfone, polytetrafluoroethene, Polyalkylacrylates, polymethyl methacrylate, unsaturated Polyesters, polylactones, polyepoxides, polyamides, polybutadienes, polyphosphazenes, Styrene maleic anhydride (SMA), styrene methyl methacrylate (SMMA), polysulfone, polyvinyl acetate and polyacrylamide. Furthermore Can be phenolic resin, polyester resin, more natural or synthetic Rubber or silicone rubber can be used. Special examples Inorganic polymers include phosphorus based compounds and Silicones. The polymers listed above may be prepared and processed in a manner known to those skilled in the art. Preferably, at least two, more preferably at least three, different polymers for the preparation of the polymer molding used.

Preferred polymer blends are: polycarbonate / polyolefin (especially polypropylene or polyethylene), polyethylene terephthalate (PET) / polyvinylidene fluoride, PET / nylon 6,6, PET / polypropylene, high density PET / polyethylene blends, polyamide 6 (PA6) / acrylonitrile-butadiene-styrene and polycarbonate / polyolefins (preferably polypropylene), polyamide 6- (PA6) / polyamide 12 (PA12), polyamide 6.6 (PA 6.6) / polyamide 12 (PA 12), aromatic polyamide / polyamide 12 (PA 12), polybutylene terephthalate / thermoplastic polyester , and polyethylene terephthalate / thermoplastic polyester. Suitable polymer blends have been used, for example, by Wu et al. (Journal of applied polymer science, 2006, vol. 99, no2, pp. 477-488) described in connection with CNT. When using a plurality of different polymers, depending on the property of the polymers, a single-phase or multi-phase system can arise.

According to the invention the polymer molding preferably consists of at least two together essentially immiscible (phase incompatible) Polymers. Be two or more phase incompatible polymers used, so they can even after melting of the polymer molding a two- or multi-phase system form. Phase-incompatible systems are those skilled in the art known. If the two polymer types are mixed, they lie in separate phases next to each other. If such a mixture over held in the melt for an extended period of time, coalesced the domains formed from one polymer species each, d. H. There is a phase separation.

For example, polymers selected from the group consisting of polystyrene (PS), polymethylmethacrylate (PMMA) and acrylonitrile-butadiene-styrene (ABS), as well as thermoplastic polyesters such as polyethylene terephthalate (PET) or polybutylene terephthalate (PBT), and polycarbonates immiscible with polypropylene and / or polypropylene copolymers. Furthermore, polystyrene and polyamide-6 are not miscible with polyethylene or polypropylene. Combinations of two or more of the aforementioned polymers are preferred according to the invention, wherein the use of polycarbonate in combination with polypropylene FITS is preferred.

at Use of polypropylene and / or a polypropylene copolymer in a mixture with phase-incompatible polymers it is preferred, in each case based on the total mass of the polymer mixture (including any auxiliary substances and carbon nanotubes), at least 40% by weight, more preferably at least 60% by weight, still more preferably at least 80% by weight, more preferably at least 90% by weight, and most preferably at least 99% by weight, of polypropylene and / or polypropylene copolymer. Further preferred Amount range are: 40 to 99 wt .-%, more preferably 60 to 95 Wt .-%, more preferably 70 to 95 wt .-%, polypropylene and / or Polypropylene copolymer.

carbon Nanotubes (CNT), also carbon nanotubes or carbon nanotubes called, are made of carbon atoms in a certain molecular arrangement trained, fibrous structures. CNTs consist of wall sections, enclose the cavities. The walls are here made of carbon atoms with three bonding partners constructed, which form a honeycomb-like structure of hexagons. Depending on the arrangement of the wall structures one speaks of single-layered Kohlenstoffnanotubes (single wall carbon nanotubes, SWCNT), the are constructed of individual tubes and an inner diameter of 1-3 nm, or of multi-layered carbon nanotubes (multi wall carbon nanotubes, MWCNT) consisting of several concentric consist of nested tubes. The outside diameter The carbon nanotubes are between 1 nm and 400 nm, with carbon Nanotubes with an outer diameter between 10 and 400 nm often as a carbon nanofiber (Carbon Nano Fiber, CNF).

The production of carbon nanotubes is known to the person skilled in the art and can be carried out, for example, in the arc process (US Pat. Iijima, Nature 354, 1991, 56-8 ) or by means of vapor deposition processes (chemical vapor deposition, CVD) ( PM Ajayan, Nanotubes from Carbon, Chem. Rev. 99, pp. 1787-1799, 1999 ). Another method is in the WO 99/13127 . DE 19946182 and WO 98/39250 described. In this case, pulsed lasers are used for the vaporization of carbonaceous materials which are arranged in a vacuum chamber. Part of the vaporized carbon molecules condenses on so-called scavengers, whose temperature is controlled by external heating and cooling, which causes the growth of nanotubes. Other manufacturing methods include, for example, arc, laser ablation and catalytic processes. WO 86/03455 and WO 2006/050903 describe production processes in which aliphatic or aromatic hydrocarbons are decomposed in the presence of an iron-containing catalyst at temperatures of 800-900 ° C. In the known processes, carbon black, amorphous carbon and high-diameter fibers are often formed as by-products. In the catalytic deposition of carbon from gaseous hydrocarbons (Catalytic Carbon Vapor Deposition), for example, acetylene, methane, ethane, ethylene, butane, Bu th, butadiene, or benzene can be used. As catalysts z. As metals such as Fe or Ni or metal oxides can be used. The carbon nanotubes produced using the above methods are most likely to be CNT powders and can be mixed directly with the polymers.

According to the invention preferably CNT with an average diameter of 2 to 100 nm, more preferably 5 to 80 nm, and more preferably 6 to 50 nm used. Preference is given to using MWCNT. Furthermore, the Skilled in the art that the carbon nanotubes depending on the symmetry or Arrangement of carbon hexagons in the tube walls have different electronic states and thus Properties of metals or semiconductors may have. Depending on the application, the person skilled in the art, therefore, the appropriate, in the Literature described, carbon nanotubes can select.

"Functionalized carbon nanotubes" can also be used according to the invention as long as these carbon nanotubes do not combine with the polymers in such a way that migration is prevented. "Functionalized carbon nanotubes" have a modified surface and are for example in US 6,203,814 and US 08 / 812,856 described.

Instead of of or in addition to the carbon nanotubes after a possible inventive Embodiment also graphene instead of the CNTs or together be used with these. Graphene and process for its preparation are known in the art. Graphenes are monatomic graphite layers, for example by epitaxial growth on a silica substrate can be produced. However, CNTs are according to the invention prefers.

According to the invention, preference is given to using carbon nanotubes in a proportion (based on the total mass of the polymer phase (s) of the polymer molding), so that the polymer molding without the conductive structures of the invention is not or only slightly conductive. For pure polycarbonate materials, therefore, for example, only less than about 5 wt .-% of CNT can be used in total. For polypropylene, a maximum of about 8-10% by weight of CNT may be used. A person skilled in the art will determine the appropriate total amount of CNT by test experiments, depending on the application of the polymer molding according to the invention.

In addition, nanocomposites may additionally be used in the process according to the invention or in the polymer moldings according to the invention. Such substances and their application are known in the art and, for example, in the EP 1 776 418 described. Nano-layered silicates, such as, for example, aluminum layered silicate, are preferably used here. Preferably, nanocomposites in a proportion, based on the total mass of the polymer phase / s in the polymer molding, of 0.1 to 10 wt .-%, preferably from 0.5 to 5 wt .-%, particularly preferably from 0.5 to 2 wt .-% used.

additionally Preferably, the polymer phase (s) of the polymer molding can / can Other substances that contain the electrical conductivity of the polymer molding can increase. For example, metal-coated carbon fiber or the like be included.

additionally Preferably, the polymer molding contains except polymeric constituents, CNT and nanocomposites not more than 20% by weight, more preferably not more than 10% by weight, of other substances, such as processing aids, Dispersing agents, adhesion and compatibilizer, Light and aging inhibitors, dyes, etc.

The term "electrically conductive" as used herein refers to a body having a surface resistance of less than 10 ⁹ , preferably less than 10 ⁷ ohms, more preferably less than 10 ⁵ , and most preferably less than 10 ⁴ ohms. Accordingly, the terms "non-electrically conductive" and "low electrical conductivity" as used herein refer to a body having a surface resistance of greater than 10 ⁹ ohms, preferably greater than 10 ⁷ ohms, more preferably greater than 10 ⁵ , and most preferably more than 10 ⁴ ohms. The method according to the invention makes it possible to reduce the surface resistance in defined regions by a factor of 10, in particular 100, in particular 1000 or more, in order to produce electrically conductive structures.

A electrically conductive structure in the sense of the present Invention is a geometric arrangement of electrically conductive Areas on the surface of a polymer molding, wherein the electrically conductive regions to electrically adjoin non-conductive areas on the surface. In particular, the electrically conductive Structures for electronic applications be formed. The electrically conductive structures can therefore have any geometric shapes, in particular the shape of Lines, areas or patterns, preferably always delimited by untreated (and thus not electrically conductive) Areas.

additionally to the electrical conductivity increases also the thermal conductivity of the thermally treated Regions of the surface of the polymer molding. This allows further technical applications.

The inventive method comprises in a first Step, providing a polymer molding at least one polymer phase containing carbon nanotubes (CNT).

In this case, one or more of the polymers listed above are mixed with the carbon nanotubes while melting the polymers. The mixing of the individual components can be done in any desired manner. Known methods for producing polymers with CNT are to melt the synthesized polymer, which is present regularly as granules, powder or in block form, by supplying heat and thus to convert it into a liquid-viscous state. This can lower the viscosity of the polymer and mix the CNT into the polymer. Such a method may be the US 4,157,325 be removed. From the Canadian disclosure CA 2,324,353 Al It is known to mix fillers in a monomer, to initiate an in situ polymerization and subsequently to melt the thus synthesized thermoplastic in order to introduce further fillers therein. Here, the carbon nanotubes can be added before or during the melting process.

For mixing substances into low-viscosity plastic precursors, it is possible, for example, to use the known dispersion processes using a bead mill, ultrasound probe, a three-roll mill or a high-pressure disperser. For mixing in high-viscosity plastic melts find the known methods such. B. the use of co-rotating twin-screw extruders z. From Coperion (DE) or Leistritz (DE), counter-rotating twin-screw extruders from Pomini (IT) and Farell (US) or the Ko-kneader manufactured by Buss (CH).

These Methods can also be used if phase incompatible Polymers are used. For example, polypropylene and / or polypropylene copolymer with phase incompatible Polymers are mixed in this way and then melted together and be mixed up. When using nanocomposites can these also added before or during the melting become.

preferably, The polymer phase (s) are / are prepared by mixing molten 0.1-10% by weight polymer, carbon nanotubes, based on the total mass of the polymer phase (s) of the polymer molding, produced.

In addition, it is possible to carry out the mixing of all components in several successive steps. For example, a polymer may first be melt-mixed with the carbon nanotubes and the resulting masterbatch mixed and melted in a subsequent step, for example after cooling and granulation, with the remaining polymers. The preparation of such masterbatches is z. In US 5,643,502 described. By using such masterbatches, the distribution of the carbon nanotubes in the plastic composition can be improved.

in this connection it is additionally preferred that the polymer molding by fusing at least one polymer phase, the carbon nanotubes (CNT) in a proportion (based on the polymer phase) between 1 and 40 wt .-%, more preferably between 5 and 30 wt .-%, more preferably 15 and 30 wt .-%, containing at least one other Polymer phase with lower carbon nanotubes (CNT) content, obtained becomes. Nevertheless, the total content of CNT should not be that high be that the polymer molding already without the inventive conductive structures is conductive. The polymer phases with different carbon nanotube (CNT) proportions here, as described above, with melting of the polymers or Polymer blends with the carbon nanotubes are obtained. Further preferred is the polymer phase with the higher carbon Nanotubes content in lower proportions by weight than the polymer phases used with lower carbon nanotubes shares. Preferably have the polymer phases with lower carbon nanotube portions between 0 and 10 wt .-% CNT (based on the polymer phase), more preferably between 0 and 5 wt .-% CNT, on. Preferably, the polymer phase with the higher carbon nanotubes share in one share between 0.5 and 40% by weight, more preferably between 1 and 40% by weight, more preferably between 1 and 30% by weight, more preferably between 1 and 20% by weight, and most preferably between 1 and 10% by weight, based on the total mass of the polymer phases of the polymer molding, be included.

It Surprisingly, it has been shown that the use of two phase incompatible polymer phases, of which a polymer phase has a high carbon nanotube content, a particularly high conductivity of the structures produced allows. It has been shown that the polymer phases also after melting (in the preparation of the polymer molding) still have different carbon nanotubes shares. In contrast this is due to the familiar use of masterbatches increased soot content, for example, in processes for coloring polymer moldings, to a uniform distribution of the soot particles on the polymer phases.

Further preferred here is the polymer phase, the carbon nanotubes (CNT) contains in a higher proportion, from one or more a plurality of polymers selected from the group consisting polycarbonate, polystyrene, acrylonitrile-butadiene-styrene (ABS), Styrene maleic anhydride (SMA), styrene methyl methacrylate (SMMA), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), Polyethylene terephthalate (PET), polyamide 6 (PA 6), polyamide 6.6 (PA 6.6), polyamide 6.4 (PA 6.4), polyamide 12 (PA 12), aromatic polyamide, polysulfone, produced. Preferably, this polymer phase is at least 50% by weight, more preferably at least 60% by weight, more preferably at least 70% by weight, more preferably at least 80% Wt .-%, and most preferably at least 90 wt .-% of polycarbonate.

The desired polymer molding can then in the usual way by extrusion or injection molding are obtained from the polymer mixtures.

In a second step of the method according to the invention, a thermal treatment of at least one surface of the polymer molding to produce the conductive, in particular the electrically conductive, structures on the surface of the polymer molding, wherein the thermal treatment is the Er heating the area of the surface to a temperature which corresponds at least to the melting temperature of the at least one polymer phase. According to a preferred embodiment, after cooling, the thermally treated areas (until the polymer phases have solidified again), one (or more) further thermal treatment of the same areas.

preferably, the thermal treatment of the surface (s) of the Polymer molding by contact with a heated body, Gas (eg hot air) or liquid, or through electromagnetic radiation. A person skilled in the art can choose the appropriate one Select means to melt a defined area of the surface.

in this connection is it possible to either post the thermal treatment previous generation of the polymer molding, d. H. after the polymer molding leave the "molding tool" has, or already in the production of such a shaped body in the mold, perform. There are already tools known in which individual parts of a shaped body in Tool specifically heated or kept hot for longer can be.

Preferably, however, electromagnetic radiation is used for the thermal treatment of the surface of the polymer molding. It is further preferred here to use laser radiation or IR radiation, more preferably laser radiation. In this case, known lithographic processes can be used for the targeted irradiation of defined areas of substrate surfaces. Methods for targeted irradiation of surfaces are known in the art and for example in the EP 0 847 329 A or WO 02/079881 A disclosed.

Suitable lasers for the method according to the invention are: He-Ne laser, Nd: YAG laser, carbon dioxide laser (CO ₂ laser), carbon monoxide laser (CO laser), nitrogen laser (N ₂ laser), argon ion laser, helium Cadmium lasers (HeCd lasers), krypton ion lasers, oxygen ion lasers, xenon ion lasers, mixed gas lasers (eg, argon and krypton), excimer lasers, metal vapor lasers (eg, copper vapor lasers), and metal halide lasers (For example, copper bromide laser), preferred are carbon dioxide (CO ₂ ) laser and Nd: YAG laser.

preferably, becomes a position of the surface of the polymer molded body heated for 0.001 to 1 second. The period of heating refers to the length of time in which the surface of the polymer molding is in a molten state. This period of time can be selected by the person skilled in the art Application and the polymers used are easily chosen. In particular, it is possible, by the duration of the heating, in which the surface is melted, the surface resistance adjust. The longer the surface melted and the deeper the melted area gets into the surface extends into it, the more carbon nanotubes migrate to the surface, whereby the electrical conductivity of the structure increases becomes.

It is additionally preferred that the surface of the polymer molding is heated to a temperature which is sufficient to melt the polymer phase (s), but not too a noticeable evaporation of the polymer phase / s leads. Of the Expression "appreciable evaporation" means that the generated conductive structure is less than 1 micron, more preferably less than 500 nm, deep in the surface of the polymer molding is.

The inventive method can in particular for Production of electronic circuits on the surface be used of the polymer molding. Thus, you can in a simple way, in particular very small components, for example produced as MIDs (molded interconnected devices). in this connection For example, the polymer moldings are used according to the invention in a standard injection molding as any moldings and then the electrically conductive Structures generated.

Of Furthermore, the invention relates to a polymer molding, comprising at least one polymer phase and between 0.01 and 10 Wt .-%, preferably between 0.1 and 10 wt .-%, more preferably between 0.1 and 10 wt .-%, more preferably between 0.1 and 8 wt .-%, and am most preferably between 0.1 and 6 wt .-%. Carbon nanotubes (CNT) (based on the total mass of the polymer phase (s) of the polymer molding), wherein the polymer molding is on the surface electrically or thermally, preferably electrically, conductive Having structures, wherein the concentration of CNT in the areas the conductive surface structures higher is as in the non-conductive surface areas.

Preferably, the polymer molding consists of those described in the foregoing, ins special polymers mentioned as preferred. More preferably, the poly merformkörper contains at least one polymer phase containing a polymer selected from the group consisting of: polycarbonate, polystyrene, acrylonitrile-butadiene-styrene (ABS), styrene maleic anhydride (SMA), styrene methyl methacrylate (SMMA), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyamide 6 (PA 6), polyamide 6.6 (PA 6.6), polyamide 6.4 (PA 6.4), polyamide 12 (PA 12), aromatic polyamide and polysulfone, polypropylene.

additionally The polymer molding preferably contains nanocomposites. Suitable nanocomposites and appropriate amounts have been previously mentioned described.

In a further preferred embodiment of the invention the polymer molding has at least two separate polymer phases on. Particularly preferably, the polymer molding contains at least two, more preferably two, polymer phases, wherein the a polymer phase consists of polymers selected from the group consisting of polystyrene (PS), polymethyl methacrylate (PMMA) and acrylonitrile-butadiene-styrene (ABS), as well as thermoplastic polyesters, such as polyethylene terephthalate (PET) or polybutylene terephthalate (PBT), and polycarbonate, as well as mixtures thereof. The second polymer phase consists of polypropylene and / or polypropylene copolymers. alternative For this purpose, the two polymer phases of polystyrene and / or Polyamide-6 in combination with polyethylene and / or polypropylene consist. Particularly preferred is the use of polycarbonate in combination with polyolefins, in particular polypropylene. The preferred ones Amounts of polypropylene and / or polypropylene copolymers are described above.

The Analysis of the finished polymer molding in terms the existing polymer phase (s) is described in the Methods section. The conductive structures (with increased CNT to part) on the surface of the polymer molding, as already mentioned, with conventional optical measuring methods be detected. More preferably, one of the Polymer phases have a higher proportion of carbon nanotubes (CNT) as the other phases.

It is also preferred that the electrically conductive structures of the polymer molding to a maximum of 10 microns, preferably not more than 1 μm, more preferably not more than 100 nm in the inside of the polymer molding (from the outer Surface on).

In a particularly preferred embodiment of the invention, the polymer molding contains a polypropylene phase and a polycarbonate phase, preferably between 50 and 80% by weight, more preferably between 60 and 80% by weight, and even more preferably between 70 and 80% by weight. Polypropylene, based on the total mass of the polymer mixture used. Particularly suitable polycarbonates can be used, such as in DE 13 002 66 or DE 14 957 30 described, are produced.

Of the Polymer molding according to the invention can be designed in particular so that its electrically conductive Surface structures Circuits or electronic circuits represent. Thus, the polymer molding as a board be used in an electronic component. On this board can according to conventional methods, such as soldering, Welding or ultrasonic welding, any Components or (electronic) components are applied.

METHODS

The following methods are used to determine the parameters of the polymer shaped bodies according to the invention:
The determination of the electrical surface conductivity was based on the measurement of the surface resistance with an ohmmeter "Metra Hit Plus" from Gossen Metrawatt GmbH according to the manufacturer. Both the resistance on the untreated surface and in each case at different points of the laser-treated surface sections were measured by means of two electrodes at a distance of 2 mm. For comparison, the surface was mechanically removed at one point and the electrical resistance in the material was measured.

The analysis of whether a polymer molding has separate polymer phases can be performed using Differential Scanning Calorimetry (DSC) DIN EN ISO 11357 respectively. In this case, the number of polymer phases can be determined on the basis of the phase transitions during melting of the polymer molding.

The determination of the melting temperature of the polymer phases or of the polymer molding can ge Mäss DIN EN ISO 3146 respectively.

The total content of CNT in the polymer molding can be determined by the pyrolytic measurement method according to DIN EN ISO 3451 be determined.

EXAMPLE

It is a polymer blend of 75% polypropylene (Repol HP-12 of Reliance, India), 3.75% CNT (Baytubes C 150 P, Bayer) and 21.25 wt .-% polycarbonate (Makrolon 2805, Fa. Bayer).

The Mixture is in a ZSE 27 / 44D twin screw extruder company Leistritz, Nuremberg with a diameter of 27 mm and a ratio L / D of 44 at a throughput of 10 kg / h with a capacity of 18 kWh melted and mixed. In the extruder was from 200 ° C to 260 ° C increasing Temperature profile set. Subsequently, a Granulation.

The polymer molded article was injection molded (device type: Arburg 270) at a temperature of 220-240 ° C in the form of round plates with 4 cm diameter. For the thermal treatment, a CO ₂ laser was used. The measured values of the surface resistances are given in the following table. Table: measuring point surface resistivity Average Unit of measurement untreated no conductivity (<10 MOhm) Laser track 2 133 122 146 1.34 kohm Laser track 3 64.3 58.9 69.1 64.1 kohm Laser track 4 23.2 21.2 24.4 22.9 kohm abraded no conductivity (<10 MOhm)

• 1. Verfahren zur Erzeugung leitfähiger Strukturen auf der Oberfläche von nicht oder nur gering leitfähigen Polymerformkörpern, umfassend die folgenden Schritte:
• a) Bereitstellen eines Polymerformkörpers aus mindestens einer Polymerphase, die Carbon Nanotubes (CNT) enthält;
• b) thermische Behandlung mindestens einer Oberfläche des Polymerformkörpers zur Erzeugung der leitfähigen Strukturen auf der Oberfläche des Polymerformkörpers, wobei die thermische Behandlung ein Erhitzen auf eine Temperatur umfasst, die mindestens der Schmelztemperatur der mindestens einen Polymerphase entspricht.
• 2. Verfahren gemäß Punkt 1, dadurch gekennzeichnet, dass die Polymerphase/n durch Vermischen von geschmolzenem Polymer mit 0,1–10 Gew.-% Carbon Nanotubes, bezogen auf die Masse der Polymerphase/n, erhalten wird/werden.
• 3. Verfahren gemäß Punkt 1 oder 2, dadurch gekennzeichnet, dass der Polymerformkörper durch Verschmelzen mindestens einer Polymerphase, die Carbon Nanotubes (CNT) in einem Anteil zwischen 1 und 40 Gew.-% enthält, mit mindestens einer weiteren Polymerphase mit geringerem Carbon Nanotubes (CNT)-Anteil, erhalten wird.
• 4. Verfahren gemäß einem der vorhergehenden Punkte, dadurch gekennzeichnet, dass die Polymerphase, die Carbon Nanotubes (CNT) in einem Anteil zwischen 1 und 40 Gew.-% enthält, ein oder mehrere Polymer/e umfasst, ausgewählt aus der Gruppe bestehend aus Polycarbonat, Polystryrol, Acrylnitrit-Butadien-Styrol (ABS), Styrolmaleinsäureanhydrid (SMA), Styrolmethylmethacrylat (SMMA), Polymethylmethacrylat (PMMA), Polybutylenterephthalat (PBT), Polyethylenterephthalat (PET), Polyamid 6 (PA 6), Polyamid 6.6 (PA 6.6), Polyamid 6.4 (PA 6.4), Polyamid 12 (PA 12), aromatischem Polyamid und Polysulfon.
• 5. Verfahren gemäß einem der vorhergehenden Punkte, dadurch gekennzeichnet, dass die thermische Behandlung der Oberfläche/n des Polymerformkörpers durch Kontakt mit einem erhitzten Körper, Gas oder Flüssigkeit, oder durch elektromagnetische Strahlung erfolgt.
• 6. Verfahren gemäß einem der vorhergehenden Punkte, dadurch gekennzeichnet, dass als elektromagnetische Strahlung Laserstrahlung oder IR-Strahlung verwendet wird.
• 7. Polymerformkörper, umfassend mindestens eine Polymerphase mit Carbon Nanotubes (CNT), wobei der Polymerformkörper auf der Oberfläche elektrisch oder thermisch leitfähige Strukturen aufweist, wobei die Konzentration der CNT in den Bereichen der elektrisch leitfähigen Oberflächenstrukturen höher ist als in den nicht elektrisch leitfähigen Oberflächenbereichen.
• 8. Polymerformkörper gemäß Punkt 7, dadurch gekennzeichnet, dass mindestens eine Polymerphase ein Polymer enthält, ausgewählt aus der Gruppe bestehend aus: Polycarbonat, Polystryrol, Acrylnitrit-Butadien-Styrol (ABS), Styrolmaleinsäureanhydrid (SMA), Styrolmethylmethacrylat (SMMA), Polymethylmethacrylat (PMMA), Polybutylenterephthalat (PBT), Polyethylenterephthalat (PET), Polyamid 6 (PA 6), Polyamid 6.6 (PA 6.6), Polyamid 6.4 (PA 6.4), Polyamid 12 (PA 12), aromatischem Polyamid und Polysulfon.
• 9. Polymerformkörper gemäß einem der Punkte 7 oder 8, dadurch gekennzeichnet, dass zwischen 0,01 und 10 Gew.-% CNT, bezogen auf die Gesamtmasse der Polymerphasen des Polymerformkörpers, enthalten sind.
• 10. Polymerformkörper gemäß einem der Punkte 7 bis 9, dadurch gekennzeichnet, dass der Polymerformkörper mindestens zwei getrennte Polymerphasen enthält.
• 11. Polymerformkörper gemäß einem der Punkte 7 bis 10, dadurch gekennzeichnet, dass eine der Polymerphasen einen höheren Anteil an Carbon Nanotubes (CNT) als die anderen Phasen aufweist.
• 12. Polymerformkörper gemäß einem der vorstehenden Punkte, wobei für den Polymerformkörper eine Polymerblend aus Polycarbonat mit Polyolefin, insbesondere mit Polypropylen oder Polyethylen, verwendet wird.

In the following, certain aspects of the invention are summarized with respect to the polymer molding disclosed herein and to methods of forming conductive structures on such polymer moldings:

• 1. A process for producing conductive structures on the surface of non-conductive or only slightly conductive polymer moldings, comprising the following steps:
• a) providing a polymer molding of at least one polymer phase containing carbon nanotubes (CNT);
• b) thermal treatment of at least one surface of the polymer molding to produce the conductive structures on the surface of the polymer molding, wherein the thermal treatment comprises heating to a temperature which corresponds at least to the melting temperature of the at least one polymer phase.
• 2. Method according to item 1, characterized in that the polymer phase (s) is / are obtained by mixing molten polymer with 0.1-10% by weight of carbon nanotubes, based on the mass of the polymer phase (s).
• 3. The method according to item 1 or 2, characterized in that the polymer molded article by fusion of at least one polymer phase containing carbon nanotubes (CNT) in an amount between 1 and 40 wt .-%, with at least one further polymer phase with a lower carbon nanotubes ( CNT) portion.
• 4. The method according to one of the preceding points, characterized in that the polymer phase containing carbon nanotubes (CNT) in an amount of between 1 and 40 wt .-% comprises one or more polymer / s selected from the group consisting of polycarbonate , Polystyrene, acrylonitrile butadiene styrene (ABS), styrene maleic anhydride (SMA), styrene methyl methacrylate (SMMA), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyamide 6 (PA 6), polyamide 6.6 (PA 6.6) , Polyamide 6.4 (PA 6.4), polyamide 12 (PA 12), aromatic polyamide and polysulfone.
• 5. The method according to any one of the preceding points, characterized in that the thermal treatment of the surface / s of the polymer molding is effected by contact with a heated body, gas or liquid, or by electromagnetic radiation.
• 6. The method according to any one of the preceding points, characterized in that as electromagnet Table radiation laser radiation or IR radiation is used.
• 7. A polymer molding comprising at least one polymer phase with carbon nanotubes (CNT), wherein the polymer molding has electrically or thermally conductive structures on the surface, wherein the concentration of CNT is higher in the regions of the electrically conductive surface structures than in the non-electrically conductive surface regions.
• 8. The polymer molding according to item 7, characterized in that at least one polymer phase contains a polymer selected from the group consisting of: polycarbonate, polystyrene, acrylonitrile butadiene styrene (ABS), styrene maleic anhydride (SMA), styrene methyl methacrylate (SMMA), polymethyl methacrylate ( PMMA), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyamide 6 (PA 6), polyamide 6.6 (PA 6.6), polyamide 6.4 (PA 6.4), polyamide 12 (PA 12), aromatic polyamide and polysulfone.
• 9. Polymer molding according to one of the items 7 or 8, characterized in that between 0.01 and 10 wt .-% CNT, based on the total mass of the polymer phases of the polymer molding, are included.
• 10. Polymer molding according to one of the items 7 to 9, characterized in that the polymer molding contains at least two separate polymer phases.
• 11. Polymer molding according to one of the items 7 to 10, characterized in that one of the polymer phases has a higher proportion of carbon nanotubes (CNT) than the other phases.
• 12. Polymer molding according to one of the preceding points, wherein for the polymer molding a polymer blend of polycarbonate with polyolefin, in particular polypropylene or polyethylene, is used.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• US 4404125 [0026]
• US 4664971 [0026]
• WO 02/19346 [0027, 0035]
• - DD 263179 [0028]
• - DE 10259498 [0029]
• WO 99/13127 [0046]
• - DE 19946182 [0046]
• WO 98/39250 [0046]
• WO 86/03455 [0046]
• - WO 2006/050903 [0046]
• US 6203814 [0048]
• US 08/812856 [0048]
• - EP 1776418 [0051]
• US 4157325 [0058]
• - CA 2324353 A1 [0058]
• US 5643502 [0062]
• - EP 0847329 A [0070]
• WO 02/079881 A [0070]
• - DE 1300266 [0081]
• - DE 1495730 [0081]

Cited non-patent literature

• T. Dekker (Carbon Nanotubes as Molecular Quantum Wires, Physics Today, pp. 22-28, 1999) [0031]
• - Wu et al. (Journal of applied polymer science, 2006, vol. 99, no2, pp. 477-488) [0041]
• - Iijima, Nature 354, 1991, 56-8 [0046]
• PM Ajayan, Nanotubes from Carbon, Chem. Rev. 99, pp. 1787-1799, 1999 [0046]
• - DIN EN ISO 11357 [0084]
• - DIN EN ISO 3146 [0085]
• - DIN EN ISO 3451 [0086]

Claims (14)

Device for creating a structure a body to be processed characterized by a Energy source with at least one electrode, which is used to deliver a Energy is provided with which of the body to be processed at least partially heated. Apparatus according to claim 1, characterized that the body to be processed is a polymer molding of at least one polymer phase containing carbon nanotubes. Apparatus according to claim 1 or 2, characterized the energy source is an electrical energy source. Apparatus according to claim 3, characterized the energy source has at least two electrodes which can be applied to the body to be processed, with the two electrodes a current through the body to be processed is conductive, which warms up the body to be processed. Apparatus according to claim 3 or 4, characterized in that the electrical energy source is a voltage source, preferably with an open circuit voltage greater than 500 V and in particular with an open circuit voltage of 1000 V. Device according to one of the preceding claims, characterized in that the structure to be generated is an electronic Circuit is. Apparatus according to claim 5 or 6, characterized that the first electrode and the second electrode in a plane or in two different levels of the body to be worked on are arranged. Device according to one of the claims 5 to 7, characterized in that the distance between the first and second electrode is less than 1 mm. Device according to one of the claims 5 to 8, characterized by a spacer, the first and connects the second electrode together. Device for creating a structure on a body to be processed with the body to be processed and a device according to any one of claims 1-9, which at least partially heats the body to be processed. Plotter with a device according to one of the preceding Claims. Matrix printer with a device according to one of preceding claims as a print matrix. Pin with a device according to one of the preceding Claims as a pen tip. Method for creating a structure on a Body to be worked, characterized in that between two different points of the body to be processed an electrical energy is passed.