DE19801985C2 - Three-dimensional deformable, multi-layer laminate and processing into a screen housing - Google Patents

Description

The present invention relates to three-dimensionally deformable, multilayered layer substances used as an intermediate in the manufacture of, versus high-frequency Radio wave shielding shield housings and shield housing parts can be used are. Such shield housings (parts) are used to house electronic Devices and / or their components required, insofar as they are electromagnetic Generate interference radiation and / or influenced by electromagnetic interference radiation to be pregnant. The invention further relates to a method for manufacturing such shield housing and shield housing parts.

The document DE 42 29 689 A1 relates to a formable film for attachment a pad and shield from radiation or to isolate electrical conductive parts. It is said to be a soft, easily malleable and different Customizable film conditions are created that act as a fastener and / or can be used as a shielding device and / or as an insulating device. For this purpose, various embodiments of multilayer laminates are proposed beat. For example, a three-layer composite material is described, the both outer layers are made of polyolefin, especially polyethylene, between which a metal mesh, in particular a copper mesh is inserted. This Copper grid or other metal foil can have a thickness of 100 to 200 µm  exhibit. Between a foil made of polyethylene material and the copper foil or The copper strip mesh can be melted using a liquid polymer Material are introduced as a binder between these two layers serves. According to an advantageous embodiment, one of the outer layers be electrically conductive; this can be done, for example, with metallic additives be incorporated into the polyolefin film.

The document EP 0 114 802 A2 relates to a multi-layer composite material an electrically conductive layer. It should be a universally applicable composite Material are provided that have a wide range of mechanical properties has and not electrostatically over a practically unlimited period is rechargeable. For this purpose, a flexible, web-shaped carrier material is provided, which with at least one external electrically conductive plastic layer is provided, which is fully connected to the carrier material. The electric conductive plastic layer consists of homo- or copolymers of Polyolefins, polyamide and polyurethane elastomers, which are electrically conductive Soot and / or graphite contained suspended. A Plastic film, a fabric, a fleece, a felt, paper, an air cushion film or Foam in sheet or tape form can be considered. For packaging Films with a special coating, such as X-ray films or films for re-photography a metal-coated polyester film can also be used as the carrier material. In In this case, the conductive plastic layer can either on the metallized or be applied over the entire surface of the non-vaporized side of the polyester film, or the layer of conductive plastic can be on both sides of the carrier material be provided.

Document DE 42 17 717 A1 relates to the use of at least one layered, electrically conductive film made of thermoplastic polyurethane as a flexible insert for containers for storing flammable liquids. The known polyurethane film is characterized in that it has at least (A) a thermoplastic polyurethane produced by the extruder process as the base raw material, further (B) carbon black with a surface area by the BET method of greater than or equal to 600 m ² / g and finally (C) optionally contains the additives known for thermoplastic polyurethanes and film production. This insert can form part of a leak protection lining of the container and thereby offers the greatest possible security against dangers from electrostatic charging.

The document DE 43 33 756 A1 relates to an electromagnetic one Interference (EMB) protected housing construction for electronic components, and a process for their production. The housing is made of plastic, and contains an EMB shielding element, which is arranged in the plastic housing and connects to the Edges of the housing are exposed and there to an electrical contact or Connector molded or otherwise connected to a mass to establish a connection for the housing. The EMB shielding element consists of an extremely flexible material, typically made of wire mesh Copper wires or the like with a diameter of 30 to 60 microns or made a metal foil provided with a multiplicity of small holes, for example Copper foil. To manufacture the housing, the EMB shielding element is placed in the Mold cavity of an injection mold inserted and then synthetic resin in the Mold cavity injected and cured.

The article "Antistatic agents for plastics" by Dr. W. Erwied in "Kunststoffe 74, 1984, Pp. 626, 627 "deals with the prevention of electrostatic charging of plastic surfaces. For this purpose, "internal anti-stat ka "can be incorporated, or it can be retrofitted on the surface of the finished plastic article "external antistatic" can be applied. To suitable Electrically conductive additives include metals, carbon black, graphite, compounds with a radical character, polyenes and molecular complexes.

Document EP 0 371 425 A2 relates to a method and an apparatus for Manufacture of deep-drawn molded plastic parts. After this, in the professional world too The process referred to as the "ultra-high pressure process" is cold-stretchable film material at a working temperature below the softening temperature of the Foil material with the aid of a fluid pressure medium under a pressure medium pressure  greater than 20 bar deformed isostatically. The deformation can occur suddenly. The too deforming film can be provided with a covering, such as a color print. The thin-walled deep-drawn part obtained can be injection molded with additional plastic and be reinforced. Typically, the initial flat film or Foil composite structure heated to a working temperature between 80 and 130 ° C and suddenly pressurized with compressed air and under a pressure medium pressure formed between 60 and 250 bar. According to this procedure, a multilayer, for example two-layer arrangement, are formed in the a color print or other covering on an inner surface of a film web located. The second layer can consist of a protective layer, for example of a Best two-component paint or preferably from another film web hen. On the inner surface of the other, unprinted film there can be a bubble-free one Adhesive layer, for example a hot-seal adhesive can be applied. The Sandwich arrangement is formed in a single step, the Color printing or covering does not come into contact with the form. The so available Thermoformed parts, which can optionally be reinforced with additional plastic typically differently colored and / or transparent wall sections and can, for example, as a housing part, illuminated sign or instrument ab cover, illuminated push button or switch button, heating panel, dashboard (from cut) or taillight lens used in motor vehicles.

The object of the present invention is to provide three-dimensionally deformable To provide multilayer laminates that are referred to above Ultra-high pressure processes (cf. EP 0 371 425 A2) are deformable, and according to their Deformation and possibly reinforcement with additional plastic shielding shield housing or shield housing for high-frequency radio waves deliver parts.

The solution to this problem according to the invention is a three-dimensionally deformable, multilayer laminate with the features specified in claim 1.  

The process of deforming these initially flat, multi-layer laminates to screen housings or screen housing parts includes those mentioned in claim 8 Activities.

Advantageous refinements and developments of the invention are the subject of the dependent claims.  

A shield housing (part) produced according to the invention typically has an essentially three-layer structure, with one Sandwich made of thermoplastic plastic sandwiched between one, with electrically highly conductive material layered metal mesh and another layer thermoplastic located; and being the with electrically highly conductive material layered metal mesh on the inside of the shield housing (parts) s and is easily contactable there.

For the explanation below, the coated Me tall fabric also as the first layer, the film made of thermoplastic chemical plastic as a second layer and the other Layer of thermoplastic also as a third Designated location.

According to an advantageous embodiment of the invention between the first layer and the second layer and / or between the second layer and the third layer each have a liability middle intermediate layer can be provided. Possibly can be an intermediate layer or both intermediate layers be additionally provided with a decorative effect.

The finished shield housing (part) forms a thin-walled dimensionally stable, largely rigid molded body with a three dimensional contour used to house electronic devices  and / or their components are suitable. A finished, largely rigid shield housing (part) can for example have a layer thickness of about 2 mm.

The three-dimensionally deformable, multi-layer laminate according to the invention is an intermediate product for the production of these largely rigid screen housings (parts). This three-dimensionally deformable, multi-layer laminate features:

• - A first layer, consisting of a 0.02 to 0.5 mm thick metal mesh that made with a coating an electrically highly conductive and highly elastic Material made of thermoplastic polyurethane filled with soot and / or metal powder is provided which - based on the binder content - 5 to 40 wt .-% Contains carbon black or metal powder; and
• - a second layer, consisting of a 0.01 to 0.8 mm thick film made of selected thermoplastic.

These two layers are permanently connected for example, about the good adhesion properties of the Be layering from the first layer to the film from the second Location. Alternatively and / or additionally, between the first layer and the second layer additionally an adhesion middle intermediate layer can be provided. The connecting the two layers can be laminated, for example consequences.

This initially flat, multilayer laminate has to Contour of the finished shield housing (part) s are deformed. According to another aspect of the invention this deformation according to the so-called ultra-high pressure process, that in documents EP-B1-0 371 425 or DE-C1-38 40 542 is described. That after such a deformation of the more layered laminate obtained three-dimensional structures is made in a manner known per se with thermoplastic art fabric (third layer) back injected to the desired strength  and surface quality of the finished shield housing to obtain (part) s.

The invention has the following advantages in particular:

• 1. Ready-to-install from the injection molding machine means with shielding and, if necessary, additional with decorated housing shells can be removed.
• 2. The contacting can be done in a simple manner on everyone Point of the inside of the housing shells, ent speaking of the arrangement of the electronic components.
• 3. The shielded housing parts are particularly simple produced.
• 4. By selecting the components for the different Layers can be the physical properties, here in particular shielding attenuation and surface resistance the shield housing (parts) varies widely become.

The invention is explained in more detail below.

The film of the second layer and the layer of the third layer consist of a thermoplastic. On one given shield housing (part) can for this film and for the layer is the same or different thermoplastic cal plastics are provided. Preferably be different plastics provided because it is in the Foil especially on the deep drawing ability and at the Layer mainly on properties like mechanical stabilizers lity, strength, scratch resistance and possibly opti transparency, clarity and shine. As ge suitable thermoplastic materials come considered per thermoplastic aromatic polycarbonates, Polyarylsulfones, cellulose esters, polyvinyl chlorides, styrene Acrylonitrile copolymers, polyphenylene oxides,  ABS graft copolymers and polymethyl methacrylate.

Suitable polycarbonates include known thermoplastic aromatic polycarbonates with weight average molecular weights Mw of 25,000 to 200,000, preferably from 30,000 to 120,000 and particularly preferably from 30,000 to 80,000 (Mw determined via η _rel in CH ₂ Cl ₂ at 20 ° C. and at a concentration of 0.5 g per 100 ml).

Suitable polyarylsulfones include known thermopla tical polyaryl fullphones, which are linear (see DE-A1-27 35 144) or branched (see DE-A1-27 35 092 or DE-A1-23 05 413) could be. Suitable linear polyarylsulfones are known aromatic polysulfones or polyethersulfones with Mw (weight average molecular weight measured for example by means of light scattering) between 15,000 and 55,000, preferably between 20,000 and 40,000. Such polyarylsulfones are for example in DE-A1-17 19 244 or US-A-33 65 517 described. Suitable branched polyarylsulfones are ins especially the branched polyaryl ether sulfones according to DE-A1-23 05 413 or US-A-39 60 815, whose Mw (weight molecular weight, measured for example by means of light scatter) between 15,000 and 50,000, preferably between Can be 20,000 and 40,000. Find more details document DE-B-30 10 143.

Suitable cellulose esters can be prepared by conventional methods by esterifying the cellulose with aliphatic monocar bonic anhydrides, preferably acetic acid and butter Acid or acetic acid and propionic anhydride become. The hydrolysis to be carried out in the raw solution is carried out controlled by a small excess of water so that a low hydroxyl content (4 to 25) is obtained. The oxy dative bleaching of the cellulose ester isolated from the solution  must be carried out in such a way that no Oxyda agent is more detectable; if necessary, a Aftertreatment with reducing agents. For determination tion of the OH number, the free hydroxyl groups of Cel luloseesters esterified with acetic anhydride in pyridine, the Excess anhydride reacted with water and back titrated (Regulation C. J. Mahn, L. B. Genung and R. F. Williams, Ana lysis of Cellulose Derivatives, Industrial and Engineering Chemistry, Vol. 14, No. 12, 935-940 (1942)). The viscosity the cellulose ester should be 0.3 to 0.5 poise, measured as 20 wt .-% solution in acetone. Preferably too Cellulose esters used have in the case of acetobutyrates an acetic acid content of 17 to 23 wt .-% and a but teric acid content of 45 to 50 wt .-%, in the case of Acetopro pionate a propionic acid content of 61 to 69 wt .-% and an acetic acid content of 2 to 7 wt .-%. The OH number len are usually between 4 and 25. The middle ones Weight average molecular weights Mw are between 10,000 and 1,000,000, preferably between 100,000 and 500,000.

Suitable thermoplastic polyvinyl chlorides are examples as the commercially available PVC types.

Suitable thermoplastic styrene-acrylonitrile copoly Merisates belong to copolymers of styrene with acrylic nitrile, for example, by suspension polymerization in the presence of catalysts of the monomers or the Mi creation of the monomers with weight average molecular weights Mw (measured in DMF at C = 5 g / l and 20 ° C) from 10,000 to 600,000 can be obtained. Suitable styrene-acrylonitrile co polymers are described, for example, in Beilstein's handbook of organic chemistry, fourth edition, Duttes supplement B 1.5, pages 1163-1169, Springer Verlag 1964, H. Ohlinger,  Polystyrene 1st part, manufacturing process and properties of products, Springer Verlag (1955).

The film of the second layer preferably consists of known thermoplastic aromatic polycarbonates. The Her The position of such polycarbonate films is, for example, in the documents DE-A1-25 17 033 and DE-A1-25 31 240 ben.

These polycarbonate films can be single-sided or double-sided be matted or structured. A suitable matting or structuring can be obtained by the melt of the thermoplastic through a wide slot nozzle is pressed out and the melting plume over a matting te or structured cooling roller is withdrawn. A sol Matting or structuring increases the bond and Adhesive strength to the adjacent layer or layer.

Suitable thermoplastic materials for the layer the third layer also includes those on the market aliphatic polyamides, for example the types of polyamides PA-6, PA-6,6, PA-11, PA-12, and thermoplastic alipha tables polyester, thermoplastic aromatic polyester, thermoplastic polyphenylene oxides and thermoplastic Polyester ether ketone. To also suitable thermo Plastic polymethyl methacrylates belong to the trade common plexiglass types. Furthermore thermoplastic ABS graft copolymers suitable, such as Mixtures of 50 to 70% graft product and 95 to 30% by weight thermoplastic styrene-acrylonitrile copolymer. Suitable graft products are the reaction products the polymerization of, for example, styrene and acrylonitrile in the presence of a rubber. These products are becoming common fig produced and contained by emulsion polymerization 5 to 80 wt% rubber. The rubber comes polybutadiene,  Natural rubber, butadiene-acrylonitrile copolymer, butadiene styrene copolymers, acrylic ester polymers, vinyl ethers polymers, EPDM terpolymers, in question. suitable ABS graft polymers are well-known commercial products products and, for example, in Ullmann's Encyclopedia of Techn. Chemie, Volume 19, page 277 ff and the one specified there Literature described.

The first layer consists of a coated metal mesh. The metal mesh ensures electromagnetic shielding against high-frequency radio waves and must be sufficient accordingly deformable to the deformation after the maximum to participate in the printing process. Suitable metal mesh can for example, consist of aluminum, copper, CrNi alloy stakes, precious metals, especially silver and made of precious steel. Copper mesh is preferably used.

Typical metal wire thicknesses range from 0.025 to 0.50 mm. The mesh size should be less than 8 mm by one to ensure adequate shielding. A preferred one Metal mesh is a mesh made from annealed copper wire a mesh size of 0.6 mm and a wire gauge of 160 µm, which has a particularly low resistance to deformation having.

The electrically conductive coating of the metal mesh ensures an electrically good conductive contact of the Metallge webes to an electronic component, a ground connection or the like of the electronic device to be housed. The electrical surface resistance of the coating should preferably be less than 200 mΩ; the specific volume resistance of the coating ρ _D should be less than 10 Ωcm.

For the coating of the metal mesh according to the first layer serve thermoplastic polyurethanes that are filled with 5 to 40% metal powder and / or soot. The Coating of the metal mesh can be done according to the known Ver drive the extrusion coating when using thermo plastically processable Pulyurethane (compare also US-A-4,810,321). A loading is preferably carried out Layering of the metal mesh by applying an aq gene dispersion of preferably linear polyester polyure thanen with a carbon black or metal powder content of 10 to 40% by weight based on the proportion of binder or by application gene solutions of preferably linear poly ester polyurethanes, which may have a higher functionality contain bright polyisocyanate as a crosslinker, also with a carbon black or metal powder content of 10 to 40% by weight moved to binder content.

As the electrical conductivity of the coating increasing metal powder, for example copper, silver or stainless steel come into consideration. The particle size of the metal powder should be less than 50 μm in order to ensure good dispersibility. The coating material is preferably made electrically conductive with the aid of carbon black. Suitable types of carbon black include conductive blacks with BET surface areas greater than 50 m ² / g and DBP adsorption greater than 80 ml / 100 g. The carbon black particles should typically have an average particle size of less than 40 μm. These electrically conductive particles are homogeneously distributed in the solution or dispersion of the coating material. This can typically be done by dispersion milling. The proportion of carbon black and / or metal powder should preferably be 10 to 40% by weight, based on the weight of solids of organic binder in the coating.

To create the coating thermoplastic polyurethanes are used for the metal mesh. Suitable polyure hand dispersions are based, for example, on linear poly ester diols and aromatic or aliphatic diisocyanates ten and possibly the usual chain extension means using the ionic structure compo nenten corresponding to US-A-3,479,310 or DE-B-14 95 847 have been asked. The aq. Are also very suitable dispersions of carboxylate and sulfonate groups pointing, preferably linear polyester polyurethanes, such as they can be obtained according to DE-A-28 04 609. In the event of the use of organic solutions of preferably Linear polyester polyurethanes are preferred solutions of non-ionic linear polyester polyurethanes in ge suitable solvents. With this polyurethane NEN is preferably a reaction product of (1) aromatic diisocyanates such as 2,4- and / or 2,6-diiso cyantotoluene, 4,4'-diisocyanatodiphenylmethane, hexamethylene diisocyanate, isophone diisocyanate, or 1,5-diisocyanatone aphthaline or mixtures thereof with (2) polyester diols of Molecular weight range (Mw) 1,000 to 4,000, in particular based on adipic acid and suitable glycols such as Ethylene glycol, 1,4-dihydroxybutane, 1,6-dihydroxyhexane and their mixtures and optionally (3) chain extension means, for example the last-mentioned glycols, where at the reactants while maintaining an NCO / OH equi valent ratio of 0.9: 1 to 1: 1.1, preferably 0.95: 1 to 1: 1 are used, and being per 1 mol Polyesterdiol optionally 0.1 to 2 mol chain extensions rer or chain extender mixture are used. Ge suitable solvents for such polyester polyurethanes are for example ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone or from such solvents  existing mixtures. The dispersions or solutions are generally with a solids content of 10 to 40 wt .-% used. It can often be useful to use the ge called solutions subordinate quantities of a higher function nelle polyisocyanate, for example on (Tris- (6-isocyanana to-hexyl) -biuret to incorporate the mechanical properties properties of the polyurethane film ultimately obtained improve.

The electrically conductive, containing soot or metal powder Polyurethane layer can either roll continuously coater or squeegee applied to the metal mesh become. The amount of the polyurethane layer depends on the metal mesh thickness used. The metal mesh should but on both sides with a closed electrically conductive capable polyurethane layer of at least 10 microns, preferred be covered with a polyurethane layer of 20 µm.

The polyurethane layers make up completely at room temperature non-tacky thermoplastic layers.

For coating the metal mesh after extrusion Coating processes are the ones which are suitable according to the invention thermoplastic polyurethanes from linear polyols, mostly Polyester or polyether, organic diisocyanates and short-chain diols (chain extenders). typi technical production can be carried out according to the so-called named belt process and extruder process.

The structural components can be used to set the properties who varies in relatively broad molar ratios the. Molar ratios of polyols to have proven successful Chain extenders from 1: 1 to 1: 12. This results in Products in the range from 80 Shore A to 75 Shore D.  

Aliphati, for example, come as organic diisocyanates cal, cycloaliphatic, araliphatic, heterocyclic and aromatic diisocyanates into consideration, such as e.g. B. in Justus Liebigs Annalen der Chemie, 562, pages 75 to 136, be be written.

Examples include: aliphatic diiso cyanates, such as hexamethylene diisocyanate, cycloaliphatic di isocyanates, such as isophorone diisocyanate, 1,4-cyclo-hexanediiso cyanate, 1-methyl-2,4- and -2,6-cyclohexane diisocyanate and the corresponding mixtures of isomers, 4,4'-, 2,4'- and 2,2'- Dicyclohexylmethane diisocyanate and the corresponding iso mixed and aromatic diisocyanates, such as 2,4-toluy Lendiisocyanate, mixtures of 2,4- and 2,6-toluenediisocya nat, 4,4'-, 2,4'- and 2,2'-diphenylmethane diisocyanate, Ge mix from 2,4 'and 4,4'-diphenylmethane diisocyanate, urethane modified liquid 4,4'- and / or 2,4'-diphenylmethane di isocyanates, 4,4'-diisocyanatodiphenylethane (1,2) and 1,5- Naphthylene. 1,4- Hexamethylene diisocyanate, isophorone diisocyanate, dicyclo hexylmethane diisocyanate, diphenylmethane diisocyanate isomers mixtures with a 4,4'-diphenylmethane diisocyanate content of greater than 96% by weight and in particular 4,4'-diphenylmethane diisocyanate and 1,5-naphthylene diisocyanate.

The diisocyanates mentioned can together with up to 15% (calculated on diisocyanate) who used polyisocyanates the; however, at most as much polyisocyanate may be added so that you still get an uncrosslinked product becomes. Suitable polyisocyanates are, for example, tri phenylmethane 4,4 ', 4 "triisocyanate and polyphenyl polymethy len polyisocyanates.

Preferred polyols are polyesters, polyethers, polycarbonates or mixtures of these.  

Suitable polyetherols can be obtained in that one or more alkylene oxides with 2 to 4 carbon atoms in the alkylene radical with a starter molecule that has two active Contains hydrogen atoms bound to be implemented. As Al Kylene oxides come, for example, ethylene oxide, 1,2-propylene oxide, epichlorohydrin and 1,2- and 2,3-butylene oxide in Be costume. Ethylene oxide, propylene oxide and Mixtures of 1,2-propylene oxide and ethylene oxide are used. The alkylene oxides can be used individually, alternately in succession or used as mixtures. As starter molecules For example, water, amino alcohols, such as N-alkyl-diethanolamines, for example N-methyl-di ethanolamine and diols such as ethylene glycol, 1,3-propylene glycol, 1,4-butanediol and 1,6-hexanediol. Gege Mixtures of starter molecules can also be used be set. Suitable polyetherols are also hydroxyl-containing polymerization products of tetra hydrofurans.

Trifunctional polyethers can also be used in proportions of 0 up to 30% by weight based on the bifunctional polyethers be set.

The substantially linear polyetherols are preferred Molecular weights from 500 to 5000. They can be both as well as in the form of mixtures with one another turn come.

Suitable polyesterols can be made, for example, from dicarbonate acids with 2 to 12 carbon atoms, preferably 4 to 6 Carbon atoms, and polyhydric alcohols become. As dicarboxylic acids, for example, come in Be traditional: aliphatic dicarboxylic acids, such as succinic acid,  Glutaric acid, adipic acid, suberic acid, azelaic acid and seba cic acid and aromatic dicarboxylic acids, such as phthalic acid, Isophthalic acid and terephthalic acid. The dicarboxylic acids can be used individually or as mixtures, e.g. B. in the form of a Bern rock, glutaric and adipic acid mixture can be used. It can optionally be used to prepare the polyesterols be advantageous instead of the dicarboxylic acids appropriate dicarboxylic acid derivatives, such as carboxylic acid diesters 1 to 4 carbon atoms in the alcohol residue, Carbonsäureanhy to use dride or carboxylic acid chlorides. examples for polyhydric alcohols are glycols with 2 to 10, preferred example, 2 to 6 carbon atoms, such as ethylene glycol, Di ethylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,10-decanediol, 2,2-dimethyl-1,3-proanediol, 1,3-propanediol and dipropylene glycol. Depending on the desired properties can the polyhydric alcohols alone or optionally can be used in a mixture with each other.

Also suitable are esters of carbonic acid with the above Diols, especially those with 4 to 6 carbon atoms, such as 1,4-butanediol and / or 1,6-hexanediol, condensation pro products of ω-hydroxycarboxylic acids, for example ω-hydroxy caproic acid and preferably polymerization products from Lactones, for example optionally substituted ω- Carpolactonen.

Preferred polyesterols are ethanediol polyadipates, 1,4-butanediol pclyadipate, ethanediol-1,4-butanediol polyadi pate, 1,6-hexanedivl-neopentyl glycol polyadipate, 1,6-hexane diol-1,4-butanediol polyadiopate and polycarpolactone ver applies.  

Polyesterols with molecular weights of 500 to 5000.

As a chain extender with the molecular weights of 62 to 500 are preferably aliphatic diols with 2 to 14 carbon atoms, e.g. B. ethanediol, 1,6-hexanediol, di ethylene glycol, dipropylene glycol and especially 1,4-butane diol into consideration. However, diesters of Te are also suitable rephthalic acid with glycols with 2 to 4 carbon atoms, such as B. terephthalic acid bis ethylene glycol or butanediol 1,4, hydroxyalkylene ether of hydroquinone, such as. B. 1,4-di (β-hydroxyethal) hydroquinone, (cyclo) aliphatic diamines, such as B. isophorone diamine, ethylenediamine, 1,2-, 1,3-propy len-diamine, N-methyl-propylenediamine-1,3, N, N'-dimethyl ethylene diamine and aromatic diamines, such as. B. 2,4- and 2,6-tolylene diamine, 3,5-diethyl-2,4- and / or -2,6-toluy len-diamine and primary ortho-di-, tri- and / or tetraalkyl substituted 4,4'-diaminodiphenylmethanes. It can too Mixtures of the chain extenders mentioned above are used become.

In addition, conventional monofunk can also be used in small quantities tional connections, e.g. B. as a chain terminator or Ent shaping aids are used. Named as an example be alcohols such as octanol and stearyl alcohol or amines such as butylamine and stearylamine.

For the production of thermoplastic polyurethanes (TPU's) can the structural components, optionally in the presence of catalysts, auxiliaries and / or additives in are reacted in such quantities that the aguiva Ratio of NCO groups to the sum of the NCO-reactive Groups, especially the OH groups of the low molecular weight  Diols / triols and polyols 0.9: 1.0 to 1.2: 1.0, preferably 0.95: 1 to 1.10: 1.0.

Suitable catalysts according to the invention are those after Tertiary amines known and customary in the art, such as B. triethylamine, dimethylcyclohexylamine, N-methyl morpholine, N, N'-dimethyl-piperazine, 2- (dimethylamino-eth oxy) ethanol, diazabicyclo (2,2,2) octane and the like such as in particular organic metal compounds such as titanium acid esters, iron compounds, tin compounds, e.g. B. tin diacetate, tin dioctoate, tin dilaurate or the tin dialkyl salts of aliphatic carboxylic acids such as dibutyltin diacetate, Dibutyltin dilaurate or the like. Preferred catalysts are organic metal compounds, especially titanium acid esters, iron and / or tin compounds.

In addition to catalysts, the structural components can also be auxiliary agents and / or additives are incorporated. Called Examples include lubricants, antiblocking agents, inhibi gates, stabilizers against hydrolysis, light, heat and ver coloring, flame retardants, dyes, pigments, inorganic and / or organic fillers and reinforcing agents.

Reinforcing agents are in particular fibrous reinforcements Kungsstoffe such. B. inorganic fibers according to the state of technology and also with a size can be acted upon.

More information about the above-mentioned auxiliary and additive substances are in the specialist literature, for example Monogra phie by J.H. Saunders and K.C. Fisch "High Polymers", Volume XVI, Polyurethane, Parts 1 and 2, Interscience Verlag Publishers 1962 or 1964 or DE-A-29 01 774 to ent to take.  

An overview of TPU's, their properties and application gene is z. B. in Kunststoffe 68 (1978), pages 819 to 825 or caoutchouc, rubber, plastics 35 (1982), pages 568 given to 584.

Depending on your needs, you can choose between the first layer and the second Location, as well as between the second location and the third location an adhesion-promoting intermediate layer can be provided. As materials for this adhesion-promoting intermediate layer ten are suitable, in addition to the polyurethane systems described men, especially the well-known acrylic and epoxy resins, so such as polyarylates, which are obtainable according to EP-A-0 443 058 and also based on linear aromatic polycarbonates Dihydroxydiphenylcycloalkanes, especially those based Dihydroxydiphenyl isophorone, which is obtained according to EP-B-0 395 953 are.

That with an aqueous polyurethane dispersion, which as electrically conductive particles 30 wt .-% carbon black - related on polyurethane binder content - contains, coated Metal mesh, for example, has an electrical upper surface resistance of 200 mΩ and shielding attenuation from 30 dB.  

The coated metal mesh can be applied to a polycar Bonat film according to the second layer at a temperature of about Laminate at 120 ° C. After that, it is handled independently barely three-dimensionally deformable, multi-layer laminate (consisting of the first layer and the second layer) ten, which as a starting material or intermediate for the manufacture position of an umbrella housing is used.

This composite produced in this way can be excellently removed the maximum pressure process according to EP-B1-0 371 425 or DE-C1- 38 40 542 deform into three-dimensional bodies, whereby Achieve deformation ratios of diameter: height of 2: 1 to let. These three-dimensional structures can in themselves known way with a thermoplastic plastic be sprayed (third layer) to the desired strength speed and surface quality of the finished screen housing to get.

The screen housings produced according to the invention can be used for for example for housing mobile phones, computers, Phono and TV devices, as well as their components and electro African components.

The following examples serve for further explanation the invention without restricting it.

Example 1 (submitted later)

A 0.05 mm thick fabric made of annealed copper wire, which has a mesh size of 0.1 mm, is coated by means of a doctor blade method with an aqueous polyurethane dispersion of a linear polyester polyurethane based on polyethylene adipinate with a molecular weight Mw of 2000 and of tolylene diisocyanate, which - based on contains the binder content - 30 wt .-% carbon black. It is then dried. The total thickness of this composite is 90 µm. The surface resistance is 100 mΩ and the shielding attenuation is 40 dB. The copper fabric coated in this way is placed on a 100 µm thick, one-sided smooth, one-sided matt film made of thermoplastic diphenol A homopolycarbonate (rel. Solution viscosity = 1.31, measured in CH ₂ Cl ₂ at 25 ° C. and a concentration of 0, 5 g / 100 ml) laminated at a temperature of 120 ° C in a roll laminator, with the matt side of the film facing the coated metal fabric. This laminate is placed in a shaping tool of an ultra-high pressure shaping system and shaped at a pressure of 300 bar. The geometry of the deformed laminate corresponds to that of the inside of a housing shell of a cell phone.

This three-dimensionally shaped laminate is opened with the side of the polycarbonate film opposite the injection point of the injection molding compound, in the present case thermoplastic diphenol A homopolycarbonate (rel. Solution viscosity = 1.24 measured in CH ₂ Cl ₂ , at a concentration of 0, 5 g / 100 ml). After the injection mold has been closed, the melt of the polycarbonate is pressed into the mold at a temperature of 280 ° C. and an injection pressure of 400 bar. After the melt has cooled, the finished screen housing part is removed from the injection mold. The screen housing part has a total layer thickness of 2 mm throughout.

Example 2

The procedure according to Example 1 is essentially repeated get; deviating is a woven fabric made of annealed metal  Copper wire with a wire thickness of 0.16 mm ver used, which has a mesh size of 0.6 mm. The Binder is an aqueous dispersion based of polybutylene adipinate with a molecular weight Mw of 4000 and a mixture of hexamethylene diisocyanate and Isophorone. This dispersion are called elek tric conductive particles 30 wt .-% - based on Binder content - copper powder with a particle size of 0.02 mm added.

The total thickness of the coated fabric is 0.22 mm, the surface resistance Ro is 150 mΩ; the umbrella attenuation is 35 dB.

This coated fabric is 0.2 mm thick Thermoplastic acrylonitrile-butadiene-styrene Copolymers with a rel. Viscosity of 1.4, the by copolymerization of 50% by weight acrylonitrile, 20% by weight Obtained butadiene and 30 wt .-% styrene according to DE-B-28 27 594 was laminated in a roll laminator at 90 ° C. This lami nat becomes one in a high pressure forming plant Contour according to the geometry of the inside of the lid of a laptop computer. Since three dimes thus obtained sional structure is made with a comparable thermoplastic injection molded plastic, as it is used for manufacturing the film has been used.

Example 3

The procedure according to Example 1 is essentially repeated picks up, differing from polycarbonate film one-sided structured, one-sided matt polycarbonate film from the Bisphenol-A homopolycarbonate of Example 1 with a thickness  of 250 µm is used. This laminate is in one Maximum pressure deformation system at 200 bar to form a shell deformed to a depth of 3.0 mm, with an outer contour corresponding to the board of a printed circuit Radio. The screen housing thus obtained is on the The board is screwed onto the earthing points.

Claims (14)

1. Three-dimensionally deformable, multi-layer laminate, which consists of
a first layer, consisting of a 0.02 to 0.5 mm thick Metallge webe, which is provided with a coating of an electrically highly conductive and highly elastic material made of soot and / or metal powder filled thermoplastic polyurethane, which - based on the binding medium content - contains 5 to 40% by weight of carbon black or metal powder; and
a second layer consisting of a 0.01 to 0.8 mm thick film made of thermoplastic, selected from thermoplastic aromatic polycarbonates, polyarylsulfones, cellulose esters, polyvinyl chlorides, styrene-acrylonitrile copolymers, polyphenylene oxides, ABS graft copolymers poly methacrylates ; and
optionally an adhesion-promoting layer is present between this first layer and this second layer. 2. Laminate according to claim 1, characterized in that the metal mesh is made of copper wire. 3. Laminate according to claim 1, characterized in that the film of the second layer is matted or structured on one or both sides.   4. Laminate according to claim 1, characterized in that between the first layer and the second layer an additional liability middle layer. 5. Laminate according to claim 1, characterized in that the thermoplastic polyurethane filled with carbon black and / or metal powder in Form of an aqueous dispersion or in the form of a solution in one organic solvent has been applied to the metal mesh. 6. Laminate according to claim 1, characterized in that the metal mesh on both sides with a closed polyurethane layer is covered, each having a layer thickness of at least 10 microns. 7. Process for the production of / against high-frequency radio waves shielding shield housing or shield housing part, characterized in that a laminate according to one of claims 1 to 6 according to the known Ultra-high pressure process is deformed. 8. The method according to claim 7, characterized in that
the first layer is laminated with the second layer; and
the composite thus obtained is deformed using the ultra-high pressure process. 9. The method according to claim 7 or 8, characterized in that the molded part obtained after the deformation to increase its stability with thermoplastic plastic is injected.   10. The method according to claim 9, characterized in that
is injected in such a way that the second layer is sandwiched between the first layer and the plastic applied during the back injection;
and the first layer is located on the inside of the screen housing (parts) and can be easily contacted there. 11. The method according to claim 9, characterized in that selected the thermoplastic used for back injection is made from thermoplastic aromatic polycarbonates, polyarylsulfones, Cellulose esters, polyvinyl chlorides, styrene-acrylonitrile copolymers, Polyamides, polyesters, polyphenylene oxides, ABS graft copolymers and polymethyl methacrylates. 12. The method according to claim 9 or 11, characterized in that when injecting a layer of thermoplastic with a Layer thickness of 0.5 to 5 mm is applied. 13. The method according to claim 9, characterized in that on the side to be coated of the molded part obtained after the deformation an adhesion-promoting layer is applied before using thermoplastic Plastic is injected. 14. The method according to claim 13, characterized in that an adhesion-promoting layer is applied, which also has a decor has a giving effect.