EP3600814A1

EP3600814A1 - Wetting nozzle having wetting pockets for producing a fibrous tape wetted with a polymer, method for producing this fibrous tape, and a wetted fibrous tape

Info

Publication number: EP3600814A1
Application number: EP18712625.5A
Authority: EP
Inventors: Christian Wilms; Herbert Börger; Henning BÖRGER
Original assignee: Covestro Deutschland AG
Current assignee: Covestro Intellectual Property GmbH and Co KG
Priority date: 2017-03-28
Filing date: 2018-03-28
Publication date: 2020-02-05
Also published as: CN110461560A; WO2018178147A1; KR20190126820A; CN110461560B; EP3381636A1; KR102453571B1; US20200016793A1

Abstract

The invention relates to a wetting nozzle having wetting pockets (1) for producing a fibrous tape wetted with a polymer. The wetting nozzle is configured as a vertically aligned slot die having a wetting slot, the opening (2) of which is oriented horizontally and runs perpendicular to the feed direction (4) of the fibrous tape. In addition, the wetting nozzle has a respective wetting pocket (1) which is connected to, but separate from, the two lateral (in the horizontal direction) ends of the opening (2) of the wetting slot, wherein the wetting pockets are moved in the feed direction (4) of the wetted fibrous tape. The invention also relates to a method for the continuous production of a fibrous tape wetted with a polymer with continuous fibres aligned unidirectionally in the flow direction of the wetted fibrous tape using the wetting nozzle according to the invention.

Description

Wetting nozzle with wetting pockets for producing a polymer-wetted sliver, method for producing this sliver and a wetted sliver

The present invention is a wetting nozzle with wetting pockets for producing a polymer-wetted sliver. The wetting nozzle is designed as a vertically oriented slot die with a wetting slot whose opening is oriented horizontally and perpendicular to the feed direction of the sliver. In this case, the wetting nozzle subsequently but separated from the two ends in the horizontal direction of the opening of the wetting slot in each case a wetting pocket, wherein the wetting pockets are continued in the feed direction of the wetted fiber sliver. The present invention also provides a process for the continuous production of a polymer-wetted fiber ribbon with unidirectionally oriented in the direction of the wet fiber ribbon continuous filaments using the wetting nozzle according to the invention.

Another object of the present invention is also an impregnated sliver that can be produced with the device according to the invention or the method according to the invention. The impregnated fiber sliver is produced from the wetted sliver by at least one further process step, one or more impregnation steps.

The longest axis of a sliver is also called running direction. By "continuous fiber" is meant that the length of the reinforcing fiber substantially corresponds to the dimension of the fiber sliver to be wetted in the orientation of the fiber. "Unidirectional" in the context of "fiber" means that the fibers in the sliver are in only one direction The advancing direction is the direction in which the sliver is moved forward during the production of the wetted sliver, the advancing direction and the running direction are parallel to each other, but the advancing direction also has a sense of direction due to the advancing movement of the sliver during the production of the wetted sliver.

The use of fiber reinforced materials has steadily increased over the past few decades due to their excellent specific properties. In particular, in accelerated structures fiber reinforced materials are used to allow weight loss without sacrificing strength and rigidity of the material, thus minimizing energy consumption.

A fiber-reinforced material, also called fiber composite material or short composite material, it is an at least two-phase material, which consists of a matrix material in which fibers are substantially completely embedded and encased. The matrix has a formative function, is to protect the fibers from external influences and is necessary to transfer forces between the fibers and to initiate external loads. The fibers contribute significantly to the mechanical performance of the material, in the industry often glass, carbon, polymer, basalt or natural fibers are used. As a matrix material - depending on the application - generally thermoset or thermoplastic

Polymers used, sometimes also elastomers.

Thermoset polymers have long been established in many industries. A decisive disadvantage, however, is the long curing time, which leads to correspondingly long cycle times during processing into components. This makes thermoset-based composites unattractive, especially for high-volume industrial applications. On the other hand, thermoplastic-based composites are often, as far as they are already present as fully consolidated semi-finished products, e.g. As continuous fiber reinforced panels or profiles, in the further processing merely heated, reshaped and cooled, which is nowadays in cycle times significantly less than a minute to realize. In addition, the processing can be carried out with further process steps, such as Combine the back molding with thermoplastics, creating a very high degree

Automation and functional integration can be achieved.

As a reinforcing material substantially semi-finished textile materials such as fabrics, multi-layer fabrics or non-wovens (also called nonwovens or random fiber mats) are used. These forms of fiber reinforcement are characterized in that already in the semi-finished textile, the orientation of the fiber - and thus the force paths in the later component - is fixed. Although this enables the direct production of a multidirectionally reinforced composite material, it has drawbacks with regard to the flexibility of the layer structure, the mechanical properties and the economic efficiency. In the case of thermoplastic-based systems, these textile semi-finished products are usually impregnated with polymer under pressure and temperature and subsequently cut to size as a hardened plate and further processed.

In addition to these already established systems based on semi-finished textile products, thermoplastic-based tapes, ie slivers impregnated with a thermoplastic polymer, are becoming increasingly important. These offer advantages in terms of cost-effectiveness, since the process step of semi-finished textile production can be saved. These thermoplastic-based tapes are suitable for the production of multilayer structures, in particular also for the production of multidirectional structures. If only "slivers" are mentioned here, they mean both slivers wetted with thermoplastic, in short also "wetted slivers", thermoplastic-impregnated slivers, also referred to for short as "impregnated slivers", and non-wetted and non-impregnated slivers. For the purposes of the present invention, "wetted sliver" means a sliver in which, in a considered length section, the entire sliver at least externally surrounded by thermoplastic. But not every single fiber must be surrounded directly by thermoplastic; it is sufficient if the surfaces of the fibers lying on the surface of the fiber band are surrounded by thermoplastic. For the purposes of the present invention, "impregnated sliver" means a sliver in which, in a considered length section, at least 80% of the surface area of all the fibers is used with the respectively used sliver

Thermoplastics are immediately surrounded; However, this does not require the surface of each fiber to be at least 80% directly surrounded by thermoplastic, it is sufficient if the sum of the surfaces of all fibers is at least 80% directly surrounded by thermoplastic. Such a longitudinal section preferably has a length of at least 10 mm, more preferably at least 100 mm, particularly preferably at least 500 mm, especially preferably at least 1000 mm.

A method and an apparatus for producing a unidirectionally continuous fiber-reinforced impregnated fiber band is described, for example, in WO 2012 123 302 A1, the disclosure of which is hereby incorporated in full in the description of the present invention.

In the disclosed in WO 2012 123 302 AI device, in particular in Figs. 1 and 3 and the associated parts of the description, the reference numeral 12 and a wetting nozzle, there called applicator provided. This wetting nozzle has a slot die (in WO 2012 123 302 AI provided with the reference numeral 14), in which a nozzle channel (in WO 2012 123 302 AI provided with the reference numeral 15) with a melt volume (in WO 2012 123 302 AI by the reference numeral 13 provided) is connected.

The device disclosed in WO 2012 123 302 A1 has as a first disadvantage that too much of the thermoplastic polymer is applied to the outer edges of the sliver. The reason for this is that the width of the wetting slot must be greater than the width of the sliver, so that a sufficient wetting of the long edges, ie the outer edges in the running direction, of the sliver takes place. However, reducing the width of the wetting slot results in incomplete wetting of the wetted fiber ribbon along its long edges. Both the excess and the lack of wetting at the long edges of the wetted sliver result in further processing to an impregnated sliver, which is not useful for the further use, for example for the production of structures of several surface-connected impregnated fiber slivers. Such improperly wetted fiber ribbons result in impregnated fiber ribbons in which the fiber volume content in the region of the long edges of the impregnated fiber ribbons is too high (with submerged wetting and consequent low impregnation) or too low (with excess wetting and consequent excess impregnation). This in turn leads to undesirable Deviations in both the thermal and mechanical properties in the region of the long edges of the impregnated fiber slivers compared to the areas of the impregnated slivers lying outside the long edges of the impregnated fiber slivers. Thus, a sub-wetting can cause the impregnated fiber ribbons are not sufficiently mechanically stable at the edges and fiberize. Also, the desired dimensions of the sliver are not complied with, both in unterschüssiger as well as excess wetting.

Since in the manufacture of multilayer multidirectional structures, the long edges of the impregnated fiber slivers are not only at the edges of the structures, but also within the structures, it comes to undesirable disturbances of the structure of such multilayer structures, to their uselessness. Therefore, prior art impregnated fiber ribbons must be trimmed along the long edges. Only in this way is it possible to provide a usable impregnated sliver for further use. This represents a further step, must be driven by the expenditure on equipment, makes the procedure more error-prone, and costs additional working time. For the purposes of the present invention, "fiber volume content" means the quotient of

Volume of fibers in a given area of the sliver and the sum of the volumes of the thermoplastic and the volume of fibers, each without the volumes of any air pockets.

Good wetting is the more difficult to achieve, the higher the fiber volume content of the impregnated fiber sliver should be. Typical fiber volume contents are in the range of 30 to 70%, preferably in the range of up to 35 to 60%, particularly preferably in the range of 40 to 50%.

In order to achieve impregnation of 90%, that is to say that in a considered length section at least 90% of the surface of all fibers are directly surrounded by the thermoplastic used in each case, the deviation from the desired fiber volume content per width section may not exceed 5%, preferably not more than 2%. For this purpose, the sliver must be very evenly wetted with the thermoplastic.

A width section of the sliver in the running direction is 1%, preferably 0.5%, more preferably 0.2%, most preferably 0.1% of the total width of the sliver, but at least 0.5 mm and a maximum of 5 mm. However, the disadvantage of cutting the impregnated fiber sliver is also the loss of material, which is particularly evident when expensive starting materials such as, for example, a polycarbonate are used as the thermoplastic matrix and carbon fibers as the fiber material. The device disclosed in WO 2012 123 302 A1 has, as a second disadvantage, that the wetting of the fiber band is difficult to set. Reason for this are, on the one hand, the relatively high viscosities of the thermoplastics used in the temperatures prevailing during the impregnation, on the other hand, the fiber slivers inhomogeneous by agglomeration of the fibers. The viscosities of the thermoplastics used are between

10 and 300 Pa * s. However, the wetting temperatures can not be arbitrarily increased, since this leads to an increased energy consumption on the one hand and to a decomposition of the thermoplastics on the other hand. The lack of adjustability of the wetting of the sliver has the consequence that the sliver is often either too little wetted, that is, in a considered length section, the entire sliver is not at least externally surrounded by thermoplastic and the deviation from the desired fiber volume content per width section more than 2 %, even more than 5%, often more than 10%. With such a poorly wetted sliver, it is not possible to produce an impregnated sliver in which at least 90% of the surface of all the fibers of an impregnated sliver impregnated with the thermoplastic used in each case. An impregnated sliver in which not at least 90% of the surface of all the fibers of an impregnated sliver impregnated with the thermoplastic used in each case, is not suitable for further processing and must therefore be disposed of as waste. This means both costs due to the loss of material and disposal of the unusable material. However, on the other hand, the pressure of a thermoplastic on the sliver can not be arbitrarily increased to promote wetting of the sliver with the thermoplastic. Excessive pressure causes excess thermoplastic to swell out the sides of the sliver, which in turn leads to increased costs due to material losses and reduced dimensional stability of both the wetted and impregnated slivers. As already explained, the cost of material losses is particularly significant when expensive starting materials such as polycarbonate are used as the thermoplastic matrix and carbon fibers as the fiber material.

Polycarbonates, in addition to the high price compared to the thermoplastics commonly used have the further disadvantage that they have little predisposition to creep and thus tend to cracking at a constant voltage. This is particularly problematic when used in composites containing continuous filaments; because composites containing endless fibers in their plastic matrix are under constant tension due to the endless fibers. For this reason, polycarbonates played in practice as plastic matrix for composites containing such continuous fibers only a minor role so far. In principle, however, it is desirable to extend the field of use of polycarbonates to the impregnated fiber ribbons, because polycarbonates have compared to the other conventional thermoplastics, such as polyamide or polypropylene, a lower volume shrinkage during solidification. Furthermore, compared to other thermoplastics, polycarbonates have a higher glass transition temperature Tg, higher heat resistance and lower water absorption.

In addition, with impregnated fiber ribbons containing polycarbonate as the matrix material, it is possible to provide a multi-layer composite having an aesthetically pleasing surface with low waviness and good mechanical properties. Such a multi-layer composite material composed of impregnated fiber ribbons with polycarbonate as the matrix material has a metal-like feel, appearance and acoustics.

With these properties, such a multilayer composite material is also suitable as a housing material for housings for electronic devices, in particular portable electronic devices such as laptops or smartphones, for the outer planking as well as for interior trim of automobiles, since such a multilayer composite material can absorb both mechanical load and an outstanding external appearance offers.

In order to make polycarbonate available for the production of impregnated fiber slivers, it is therefore also necessary to take special care in wetting the sliver, which is not guaranteed in the prior art. The object of the present invention is to overcome the disadvantages of the prior art.

In particular, the object of the present invention is to provide a device which is suitable for wetting a non-wetted sliver in such a way that, on the one hand, the entire sliver is at least externally surrounded by thermoplastic in a considered longitudinal section, and on the other hand the deviation of the desired fiber volume content per width section is at most 5%, preferably at most 2%.

Preferably, moreover, the amount of the excess of thermoplastic needed to effect such wetting should be at most 5%, preferably at most 3%, most preferably at most 1% of the amount of thermoplastic, all in all for the wetting of a non-wetted sliver is consumed, ie the amount that adheres in the impregnated sliver, increased by the amount of excess. In this case, the impregnated sliver produced from the wetted sliver should not have to be trimmed to achieve the desired degree of impregnation. More preferably, at least 90%, particularly preferably at least 95%, of the surface area of all fibers of an impregnated fiber sliver produced from the fiber sliver wetted according to the invention is impregnated with the thermoplastic used in each case. Further preferably, the degree of impregnation in each width section of the impregnated fiber sliver should differ by a maximum of 10%, preferably not more than 5%, particularly preferably not more than 2%, from the average degree of impregnation of the impregnated fiber sliver.

Such a degree of impregnation is - if the sliver after impregnation is not to be cut along its long edges - to achieve only a good wetting of the sliver with the thermoplastic used. It is also an object of the present invention to provide a device can be prepared with the wetted slivers with polycarbonate as the matrix material. From these wetted slivers can then be produced by at least one further process step, in particular one or more impregnation steps, impregnated slivers. These impregnated fiber ribbons with polycarbonate as matrix material produced from the wetted fiber ribbons should be suitable for producing multilayer composite materials with a metal-like feel, appearance, acoustics and an excellent external appearance as well as the ability to absorb mechanical load. Such multilayer composite materials are then suitable as housing material for housings for electronic devices, in particular portable electronic devices such as laptops or smartphones, for exterior planking and for interior trim of automobiles.

The problem is solved by the device according to the present main claim. The device according to the invention is characterized in that it has a wetting nozzle with wetting pockets for the production of a thermoplastic-wetted sliver. The wetting nozzle has at both horizontally lateral ends of the opening of the

Wetting slit each a wetting pocket on.

In this case, the wetting nozzle then has a wetting pocket separated from the two horizontally lateral ends of the opening of the wetting slot.

Such a wetting pocket joins laterally in the horizontal direction directly to the opening of the wetting slot and continues in the feed direction of the wetted sliver, wherein the wetting pocket has a smaller depth than the wetting slot and is connected only via the wetting slot with the supply of thermoplastic. The wetting bag can, for example, in plan view, that is perpendicular to the opening of the nozzle slot view, semicircular, halbovalförmig, in the form of a pitch circle with an angle A of 120 ° to 135 ° with attached, in the feed direction pointed expiring triangle or be formed in any other meaningful shape. Preferably, the wetting bag in the plan view is semicircular or in the form of a pitch circle with an angle A of 120 ° to 135 ° with attached, pointed in the feed direction expiring triangle, in particular in the form of a pitch circle with an angle A of 120 ° to 135 ° with attached , in the feed direction pointy expiring triangle. The leg of the triangle, which adjoins the contour of the pitch circle in the feed direction, emerges tangentially from the pitch circle. On the one hand, such a shaped wetting pouch makes it possible to provide sufficient matrix material for wetting, especially where the matrix material comes into contact with the previously unwetted or slightly wetted fiber sliver, and on the other hand, with increasing degree of wetting, makes less and less matrix material available to avoid excess wetting. The pointed end of the triangle also causes a sharp separation between the now wetted sliver and the matrix material of the wetting pocket. The two wetting pockets at the two lateral ends of the opening of the

Wetting slot are preferably arranged mirror-symmetrically in the feed direction and configured, but it is also possible to provide at the two lateral ends of the opening of the wetting slot wetting pockets, which are not mirror-symmetrical to each other. The radius R of a wetting pocket is adapted to the viscosity of the thermoplastic used. Preferably, the radius is from 0.5 mm to 2 mm, in particular about 1 mm.

According to the invention, the wetting nozzle is constructed from a plurality of mutually movable parts. In this way, the width of the slot and thus also the width of the opening of the slot of the type and composition of the matrix material and the conditions for producing the impregnated fiber sliver can be adjusted. The opening of the slot usually has a width of 0.1 to 1 mm.

In the context of the present invention, an impregnated fiber sliver has a matrix which consists of at least 50% by weight, preferably at least 70% by weight, particularly preferably at least 90% by weight, of one or more thermoplastics. In this case, the thermoplastic is preferably selected from one or more of the series comprising polycarbonate, polyamide, polyethylene, polypropylene, polyphenylene sulfone, polyetherimide, a polyether ketone such as polyetheretherketone, polyetherketone ketone, polyetheretheretherketone, polyetheretherketone ketone, poly (etherketone etherketonketon), and thermoplastic polyurethane. Particularly preferred is the thermoplastic polycarbonate. In addition, the matrix material may contain up to 50.0% by weight, preferably up to 30% by weight, particularly preferably up to 10% by weight of customary additives.

This group includes flame retardants, anti-dripping agents, thermal stabilizers, mold release agents, antioxidants, UV absorbers, IR absorbers, antistatic agents, optical brighteners, light scattering agents, colorants such as pigments, including inorganic pigments, carbon black and / or dyes, and inorganic fillers in the usual for polycarbonate Amounts. These additives may be added individually or in admixture.

Such additives as are customarily added in the case of polycarbonates are described, for example, in EP-A 0 839 623, WO-A 96/15102, EP-A 0 500 496 or "Plastics Additives Handbook", Hans Zweifel, 5th Edition 2000, Hanser Verlag , Munich described.

When talking about polycarbonate, it also means mixtures of different polycarbonates. Furthermore, polycarbonate is used here as a generic term and thus includes both homopolycarbonates and copolycarbonates. The polycarbonates may also be linear or branched in a known manner. The polycarbonate preferably consists of 70% by weight, preferably 80% by weight, particularly preferably 90% by weight or substantially, in particular 100% by weight, of a linear polycarbonate.

The preparation of the polycarbonates can be carried out in a known manner from diphenols, carbonic acid derivatives, optionally chain terminators and branching agents. Details of the preparation of polycarbonates have been well known to those skilled in the art for at least about 40 years. For example, see Schnell, Chemistry and Physics of Polycarbonates, Polymer Reviews, Volume 9, Interscience Publishers, New York, London, Sydney 1964, D. Freitag, U. Grigo, P.R. Müller, H. Nouvertne, BAYER AG, Polycarbonates in Encyclopaedia of Polymer Science and Engineering, Volume 11, Second Edition, 1988, pages 648-718, and finally U. Grigo, K. Kirchner and P.R. Müller Polycarbonates in BeckerBraun, Plastic Manual, Volume

31, polycarbonates, polyacetals, polyesters, cellulose esters, Carl Hanser Verlag Munich, Vienna 1992, pages 117-299 referenced.

The preparation of aromatic polycarbonates is carried out, for example, by reacting diphenols with carbonyl halides, preferably phosgene, and / or with aromatic dicarboxylic acid dihalides, preferably benzenedicarboxylic acid dihalides, by the interfacial method, if appropriate using chain terminators and if appropriate using trifunctional or more than trifunctional branching agents. Likewise, a preparation via a melt polymerization by reaction of Diphenols possible with, for example, diphenyl carbonate. Examples of suitable diphenols for the preparation of the polycarbonates are hydroquinone, resorcinol, dihydroxydiphenyls, bis (hydroxyphenyl) alkanes, bis (hydroxyphenyl) cycloalkanes, bis (hydroxyphenyl) sulfides, bis (hydroxyphenyl) ether, bis ( hydroxyphenyl) ketones, bis (hydroxyphenyl) sulfones, bis (hydroxyphenyl) sulfoxides, α-α'-bis (hydroxyphenyl) diisopropylbenzenes, phthalimidines derived from isatin or phenolphthalein derivatives and their nuclear alkylated, nuclear-arylated and nuclear-halogenated compounds.

Preferably, in the diphenols based on phthalimides, such as 2-aralkyl-3,3'-bis (4-hydroxyphenyl) -phthalimide or 2-aryl-3,3'-bis (4-hydroxyphenyl) - phthalimides such as 2-phenyl-3,3'-bis (4-hydroxyphenyl) phthalimide, 2-alkyl-3,3'-bis (4-hydroxyphenyl) phthalimides such as 2-butyl-3,3'-bis - (4-hydroxyphenyl) -phthalimides, 2-propyl-3,3'-bis- (4-hydroxyphenyl) -phthalimides, 2-ethyl-3,3'-bis- (4-hydroxyphenyl) -phthalimides or 2-methyl -3,3'-bis (4-hydroxyphenyl) phthalimides and diphenols based on nitrogen-substituted isatines such as 3,3-bis (4-hydroxyphenyl) -1-phenyl-1H-indol-2-one or 2 , 2-bis (4-hydroxyphenyl) -1-phenyl-1H-indol-3-one used.

Preferred diphenols are 4,4'-dihydroxydiphenyl, 2,2-bis (4-hydroxyphenyl) -propane (bisphenol A), 2,4-bis (4-hydroxyphenyl) -2-methylbutane, 1,1-bis- (4-hydroxyphenyl) -p-diisopropylbenzene, 2,2-bis (3-methyl-4-hydroxyphenyl) -propane, dimethyl-bisphenol A, bis- (3,5-dimethyl-4-hydroxyphenyl) -methane, 2 , 2-bis- (3,5-dimethyl-4-hydroxyphenyl) -propane, bis- (3,5-dimethyl-4-hydroxyphenyl) -sulfone, 2,4-bis- (3,5-dimethyl-4-) hydroxyphenyl) -2-methylbutane, 1,1-bis- (3,5-dimethyl-4-hydroxyphenyl) -p-diisopropylbenzene and 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane.

Particularly preferred diphenols are 2,2-bis- (4-hydroxyphenyl) -propane (bisphenol A), 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) -propane, 1,1-bis (4 -hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane and dimethyl-bisphenol A.

These and other suitable diphenols are e.g. in US-A 3,028,635, US-A 2,999,825, US-A 3,148,172, US-A 2,991,273, US-A 3,271,367, US-A 4,982,014 and US-A 2,999,846, in DE-A 1 570 703, DE-A 2063 050, DE-A 2 036 052, DE-A 2 211 956 and DE-A 3 832 396, in FR-A 1 561 518, in the monograph H. Schnell, Chemistry and Physics of Polycarbonates, Interscience Publishers, New York 1964 and JP-A 620391986, JP-A 620401986 and JP-A 1055501986.

In the case of homopolycarbonates, only one diphenol is used; in the case of copolycarbonates, several diphenols are used. Suitable carbonic acid derivatives are, for example, phosgene or diphenyl carbonate. Suitable chain terminators that can be used in the preparation of the polycarbonates are monophenols. Suitable monophenols are, for example, phenol itself, alkylphenols such as cresols, p-tert-butylphenol, cumylphenol, and mixtures thereof. Preferred chain terminators are the phenols which are mono- or polysubstituted with Cl- to C30-

Alkyl radicals, linear or branched, preferably unsubstituted, or substituted with tert-butyl. Particularly preferred chain terminators are phenol, cumylphenol andor p-tert-butylphenol. The amount of chain terminator to be used is preferably 0.1 to 5 mol%, based on moles of diphenols used in each case. The addition of the chain terminators can be carried out before, during or after the reaction with a carbonic acid derivative.

Suitable branching agents are the trifunctional or more than trifunctional compounds known in polycarbonate chemistry, especially those having three or more than three phenolic OH groups.

Suitable branching agents are, for example, 1,3,5-tri (4-hydroxyphenyl) benzene, 1,1,3-tri (4-hydroxyphenyl) ethane, tri- (4-hydroxyphenyl) -phenyl methane, 2,4- Bis (4-hydroxyphenylisopropyl) phenol, 2,6-bis (2-hydroxy-5'-methylbenzyl) -4-methylphenol, 2- (4-hydroxyphenyl) -2- (2,4-dihydroxyphenyl) -propane, tetra- (4-hydroxyphenyl) -methane, tetra- (4- (4-hydroxyphenylisopropyl) -phenoxy) -methane and 1,4-bis - ((4,4-dihydroxytriphenyl) -methyl) -benzene and 3,3-bis (3-methyl-4-hydroxyphenyl) -2-oxo-2,3-dihydroindole. The amount of optionally used branching agent is preferably from 0.05 mol% to 3.00 mol%, based on moles of diphenols used in each case. The branching agents may either be initially charged with the diphenols and the chain terminators in the aqueous alkaline phase or may be added dissolved in an organic solvent prior to phosgenation. In the case of the transesterification process, the branching agents are used together with the diphenols. Particularly preferred polycarbonates are the homopolycarbonate based on bisphenol A, the

Homopolycarbonate based on 1,3-bis- (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane and the copolycarbonates based on the two monomers bisphenol A and 1,1-bis (4-hydroxyphenyl) -3,3, 5-trimethylcyclohexane.

Furthermore, copolycarbonates can also be used. For the preparation of these copolycarbonates 1 wt .-% to 25 wt .-%, preferably 2.5 wt .-% to 25 wt .-%, particularly preferably 2.5 wt .-% to 10 wt .-%, based on the total amount of diphenols to be used, hydroxyaryloxy endblocked polydiorganosiloxanes can be used. These are known (US Pat. No. 3,419,634, US Pat. No. 3,189,662, EP 0 122 535, US Pat. No. 5,227,449) and US Pat produced by literature methods. Also suitable are polydiorganosiloxane-containing copolycarbonates; the preparation of the polydiorganosiloxane-containing copolycarbonates is described, for example, in DE-A 3 334 782.

The polycarbonates may be present alone or as a mixture of polycarbonates. It is also possible to use the polycarbonate or the mixture of polycarbonates together with one or more plastics other than polycarbonate as a blend partner.

Suitable blend components are polyamides, polyesters, in particular polybutylene terephthalate and polyethylene terephthalate, polylactide, polyethers, thermoplastic polyurethane, polyacetal, fluoropolymer, in particular polyvinylidene fluoride, polyethersulfones, polyolefin, in particular polyethylene and polypropylene, polyimide, polyacrylate, in particular poly (methyl) methacrylate, polyphenylene oxide, polyphenylene sulfide , Polyether ketone, polyaryletherketone, styrene polymers, in particular polystyrene, styrene copolymers, in particular styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene block copolymers and polyvinyl chloride.

Polyamides which are suitable according to the invention are likewise known or can be prepared by processes known from the literature.

Polyamides suitable according to the invention are known homopolyamides, copolyamides and mixtures of these polyamides. These may be partially crystalline and / or amorphous polyamides. Polycrystalline polyamides which are suitable are polyamide-6, polyamide-6,6, mixtures and corresponding copolymers of these components. Also suitable are partially crystalline polyamides, the acid component of which wholly or partly consists of terephthalic acid and / or isophthalic acid and / or suberic acid and / or sebacic acid and / or azelaic acid and / or adipic acid and / or cyclohexanedicarboxylic acid, whose diamine component is wholly or partly derived from m- and / or p-xylylenediamine and / or hexamethylenediamine and / or 2,2,4-trimethylhexamethylenediamine and / or 2,4,4-trimethylhexamethylenediamine and / or isophoronediamine and whose composition is known in principle.

Also to be mentioned are polyamides which are wholly or partly made of lactams having 7 to 12 carbon atoms in the ring, optionally with the concomitant use of one or more of the above-mentioned starting components.

Particularly preferred semi-crystalline polyamides are polyamide-6 and polyamide-6,6 and their mixtures. As amorphous polyamides known products can be used. They are obtained by polycondensation of diamines such as ethylenediamine, hexamethylenediamine, decamethylenediamine, 2,2,4- and / or 2,4,4-trimethyl-hexamethylenediamine, m- and / or p-xylylenediamine, bis (4-aminocyclohexyl) - methane, bis (4-aminocyclohexyl) -propane, 3,3'- Dimethyl 4,4'-diamino-dicyclohexylmefhan, 3-aminomethyl-3,5,5-trimethylcyclohexylamine, 2,5- and / or 2,6-bis- (aminomethyl) -norbornane and / or 1,4- Diaminomethylcyclohexane with dicarboxylic acids such as oxalic acid, adipic acid, azelaic acid, decanedicarboxylic acid, heptadecanedicarboxylic acid, 2,2,4- and / or 2,4,4-trimethyladipic acid, isophthalic acid and terephthalic acid.

Copolymers obtained by polycondensation of several monomers are also suitable, and copolymers which are prepared with addition of aminocarboxylic acids such as e-aminocaproic acid, w-aminoundecanoic acid or w-aminolauric acid or their lactams.

Particularly suitable amorphous polyamides are the polyamides prepared from isophthalic acid, hexamethylenediamine and further diamines such as 4,4-diaminodicyclohexylmethane, isophoronediamine, 2,2,4- and / or 2,4,4-trimethylhexa-methylenediamine, 2 5 and / or 2,6-bis (aminomethyl) norbornene; or from isophthalic acid, 4,4'-diamino-dicyclohexylmefhan and ε-caprolactam; or isophthalic acid, 3,3'-dimethyl-4,4'-diamino-dicyclohexylmefan and laurolactam; or from terephthalic acid and the isomer mixture of 2,2,4- and / or 2,4,4-trimethylhexamethylenediamine.

Instead of the pure 4,4'-diaminodicyclohexylmefhans, it is also possible to use mixtures of the positional isomers diaminedicyclohexalmethanes, which are composed of

70 to 99 mol% of the 4,4'-diamino isomer,

1 to 30 mol% of the 2,4'-diamino isomer and 0 to 2 mol% of the 2,2'-diamino isomer, optionally corresponding to higher condensed diamines, which are obtained by hydrogenation of diaminodiphenylmethane technical grade. The isophthalic acid may be replaced by terephthalic acid up to 30%.

The polyamides preferably have a relative viscosity (measured on a 1 wt .-% solution in m-cresol at 25 ° C) of 2.0 to 5.0, more preferably from 2.5 to 4.0.

Thermoplastic polyurethanes which are suitable according to the invention are likewise known or can be prepared by processes known from the literature.

An overview of the production, properties and applications of thermoplastic polyurethanes (TPU) can be found in the Kunststoff Handbuch [G. Becker, D. Braun], volume 7 "Polyurethane", Munich, Vienna, Carl Hanser Verlag, 1983. TPUs are usually composed of linear polyols (macrodiols), such as polyester, polyether or polycarbonate diols, organic diisocyanates and short-chain, mostly difunctional alcohols (chain extenders). They can be produced continuously or discontinuously. The best known production methods are the belt process (GB-A 1 057 018) and the extruder process (DE-A 19 64 834).

The thermoplastic polyurethanes used are reaction products of

I) organic diisocyanates

Π) polyols

ΠΙ) chain extenders. As diisocyanates (I) it is possible to use aromatic, aliphatic, araliphatic, heterocyclic and cycloaliphatic diisocyanates or mixtures of these diisocyanates (compare HOUBEN-WEYL "Methods of Organic Chemistry", Volume E20 "Macromolecular Materials", Georg Thieme Verlag, Stuttgart, New York 1987, pp. 1587-1593 or Justus Liebigs Annalen der Chemie, 562, pages 75 to 136).

Specific examples are: aliphatic diisocyanates, such as hexamethylene diisocyanate, cycloaliphatic diisocyanates, such as isophorone diisocyanate, 1,4-cyclohexane diisocyanate, 1-methyl-2,4-cyclohexane diisocyanate and 1-methyl-2,6-cyclohexane diisocyanate and the corresponding isomer mixtures, 4,4'-dicyclohexylmethane diisocyanate, 2,4'-dicyclohexylmethane diisocyanate and 2,2'-dicyclohexylmethane diisocyanate and the corresponding isomer mixtures, aromatic diisocyanates such as 2,4-tolylene diisocyanate, mixtures from 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate and 2,2'-diphenylmethane diisocyanate, mixtures of 2,4'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate. Diphenylmethane diisocyanate, urethane-modified liquid 4,4'-diphenylmethane diisocyanates and 2,4'-Diphenylmethandiiso-cyanates, 4,4'-diisocyanatodiphenyl-ethane (l, 2) and 1,5-naphthylene diisocyanate. Preferably used are 1,6-hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexyl methane diisocyanate, diphenylmethane diisocyanate

Isomer mixtures with a 4,4'-diphenyl-methane diisocyanate content of> 96 wt .-% and in particular 4,4'-diphenylmethane diisocyanate and 1,5-naphthylene diisocyanate. The diisocyanates mentioned can be used individually or in the form of mixtures with one another. They may also be used together with up to 15% by weight (calculated on the total amount of diisocyanate) of a polyisocyanate, for example triphenylmethane-4,4 ', 4 "-triisocyanate or polyphenyl-poly-methylene-polyisocyanates. Zerewitinoff-active polyols (II) are those having an average of at least 1.8 to at most 3.0 Zerewitinoff active hydrogen atoms and a number average molecular weight M _n of 500 to 10,000 g / mol, preferably 500 to 6000 g / mol.

Included are in addition to amino groups, thiol groups or carboxyl-containing compounds in particular two to three, preferably having two hydroxyl groups

Compounds, especially those with number average molecular weights M _n of 500 to 10,000 g / mol, more preferably those having a number average molecular weight M _n of 500 to 6000 g / mol; For example, hydroxyl-containing polyesters, polyethers, polycarbonates and polyesteramides or mixtures of these. Suitable polyether diols can be prepared by reacting one or more alkylene oxides having 2 to 4 carbon atoms in the alkylene radical with a starter molecule containing two active hydrogen atoms bonded. Examples of alkylene oxides which may be mentioned are: ethylene oxide, 1,2-propylene oxide, epichlorohydrin and 1,2-butylene oxide and 2,3-butylene oxide. Preferably used are ethylene oxide, propylene oxide and mixtures of 1,2-propylene oxide and ethylene oxide. The alkylene oxides can be used individually, alternately in succession or as mixtures. Examples of suitable starter molecules are: water, amino alcohols, such as N-alkyldiethanolamine, for example N-methyldiethanolamine and diols, such as ethylene glycol, 1,3-propylene glycol, 1,4-butanediol and 1,6-hexanediol. Optionally, mixtures of starter molecules can be used. Suitable polyetherols are also the hydroxyl-containing poly merisationsprodukte of tetrahydrofuran. It is also possible to use trifunctional polyethers in proportions of from 0 to 30% by weight, based on the bifunctional polyethers, but at most in such an amount that a still thermoplastically processable product is formed. The substantially linear polyether diols preferably have number average molecular weights M _n of 500 to 10,000 g / mol, more preferably 500 to 6000 g / mol. They can be both individually and in the form of

Mixtures with each other are used.

Suitable polyester diols can be prepared, for example, from dicarboxylic acids having 2 to 12 carbon atoms, preferably 4 to 6 carbon atoms, and polyhydric alcohols. Suitable dicarboxylic acids are, for example: aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid and sebacic acid, or aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid. The dicarboxylic acids can be used individually or as mixtures, for example in the form of an amber, glutaric and adipic acid mixture. For the preparation of the polyester diols, it may optionally be advantageous, instead of the dicarboxylic acids, to use the corresponding dicarboxylic acid derivatives, such as carbonic acid diesters having 1 to 4 carbon atoms in the alcohol radical, Carboxylic anhydrides or carboxylic acid chlorides to use. Examples of polyhydric alcohols are glycols having 2 to 10, preferably 2 to 6 carbon atoms, for example ethylene glycol, diethylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,10-decanediol, 2,2-dimethyl -l, 3-propanediol, 1,3-propanediol or di-propylene glycol. Depending on the desired properties, the polyhydric alcohols may be used alone or mixed with each other. Also suitable are esters of carbonic acid with the diols mentioned, in particular those having 4 to 6 carbon atoms, such as 1,4-butanediol or 1,6-hexanediol, condensation products of co-hydroxycarboxylic acids such as co-hydroxycaproic acid or polymerization of lactones, for example, if appropriate substituted co-caprolactones. Ethanediol polyadipates, 1,4-butanediol polyadipates, ethanediol-1,4-butanediol polyadipates, 1,6-hexanediol neopentylglycol polyadipates, 1,6-hexanediol-1,4-butanediol polyadipates and .alpha. Are preferably used as polyester diols

Polycaprolactones. The polyester diols have number-average molecular weights M _n of 500 to 10,000 g / mol, more preferably 600 to 6000 g / mol and can be used individually or in the form of mixtures with one another. Zerewitinoff-active polyols (III) are so-called chain extenders and have an average of 1.8 to 3.0 Zerewitinoff-active hydrogen atoms and have a number average molecular weight M _n of 60 to 500 g / mol. By these is meant, in addition to amino groups, thiol groups or carboxyl-containing compounds, those having two to three, preferably two hydroxyl groups. The chain extenders used are diols or diamines having a molecular weight of 60 to 495 g / mol, preferably aliphatic diols having 2 to 14 carbon atoms, for example ethanediol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol and dipropylene glycol. Also suitable, however, are diesters of terephthalic acid with glycols having 2 to 4 carbon atoms, for example terephthalic acid-bis-ethylene glycol or terephthalic acid bis-1,4-butanediol, hydroxy-alkylene ethers of hydroquinone, eg 1,4-di (β-hydroxyethyl) - hydroquinone, ethoxylated bisphenols, eg 1,4-di (β-hydroxyethyl) bisphenol A, (cyclo) aliphatic diamines, such as isophoronediamine, ethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, N-methylpropylene 1, 3 -diamine, Ν, Ν'-dimethylethylenediamine and aromatic diamines, such as 2,4-toluenediamine, 2,6-toluenediamine, 3,5-diethyl-2,4-toluylenediamine or 3,5-diethyl-2,6-toluylenediamine or primary mono-, di-, tri- or tetraalkyl-substituted 4,4'-diaminodiphenylmethanes. Ethanediol, 1,4-butanediol, 1,6-hexanediol, 1,4-di (β-hydroxyethyl) hydroquinone or 1,4-di (β-hydroxyethyl) bisphenol A are particularly preferably used as chain extenders. It is also possible to use mixtures of the abovementioned chain extenders. In addition, smaller amounts of triols can be added. Compounds which are monofunctional with respect to isocyanates can be used in proportions of up to 2% by weight, based on thermoplastic polyurethane, as so-called chain terminators or mold release aids. Suitable examples are monoamines such as butyl and di-butylamine, octylamine, stearylamine, N-methylstearylamine, pyrrolidine, piperidine or cyclohexylamine, monoalcohols such as butanol, 2-ethylhexanol, octanol, dodecanol, stearyl alcohol, the various amyl alcohols, cyclohexanol and ethylene glycol monomethyl ether.

The relative amounts of the compounds (II) and (ΠΙ) are preferably chosen such that the ratio of the sum of the isocyanate groups in (I) to the sum of the Zerewitinoff-active hydrogen atoms in (II) and (III) is 0.85: 1 to 1, 2: 1, preferably 0.95: 1 to 1.1: 1. The thermoplastic polyurethane elastomers (TPU) used according to the invention can as adjuvants and additives up to a maximum of 20 wt .-%, based on the total amount of TPU, the customary auxiliaries and additives. Typical auxiliaries and additives are catalysts, pigments, dyes, flame retardants, stabilizers against aging and weathering, plasticizers, lubricants and mold release agents, fungistatic and bacteriostatic substances and fillers and mixtures thereof.

Suitable catalysts are the tertiary amines known and customary in the art, e.g. Triethylamine, dimethylcyclohexylamine, N-methylmorpholine, Ν, Ν'-dimethylpiperazine, 2- (dimethylaminoethoxy) ethanol, diazabicyclo [2,2,2] octane and the like, and in particular organic metal compounds such as titanic acid esters, iron compounds or tin compounds such as tin diacetate, tin dioctoate, Tin dilaurate or the tin dialkyl salts of aliphatic carboxylic acids such as dibutyltin diacetate or dibutyltin dilaurate or the like. Preferred catalysts are organic metal compounds, in particular titanic acid esters, iron and tin compounds. The total amount of catalysts in the TPU is generally about 0 to 5 wt .-%, preferably 0 to 2 wt .-%, based on the total amount of TPU. Examples of other additives are lubricants, such as fatty acid esters, their metal soaps,

Fatty acid amides, fatty acid ester amides and silicone compounds, anti-blocking agents, inhibitors, hydrolysis stabilizers, light, heat and discoloration, flame retardants, dyes, pigments, inorganic and / or organic fillers and reinforcing agents. Reinforcing agents are, in particular, fibrous reinforcing materials, for example inorganic fibers, which are produced according to the prior art and can also be treated with a sizing agent. Further details of the abovementioned auxiliaries and additives are the specialist literature, for example, the monograph by JH Saunders and KC Fresh "High Polymers", Volume XVI, polyurethanes, Part 1 and 2, published by Interscience Publishers 1962 and 1964, the paperback for plastic Additives by R. Gächter u. H. Müller (Hanser Verlag Munich 1990) or DE-A 29 01 774. Other additives which can be incorporated into the TPU are thermoplastics, for example polycarbonates and acrylonitrile / butadiene / styrene terpolymers, in particular ABS. Other elastomers such as rubber, ethylene / vinyl acetate copolymers, styrene / butadiene copolymers and other TPU's can also be used. Also suitable for incorporation are commercially available plasticizers such as phosphates, phthalates, adipates, sebacates and alkylsulfonic acid esters.

Polyethylene which is suitable according to the invention is likewise known or can be prepared by processes known from the literature. The polyethylene may be PE-HD (HDPE), PE-LD (LDPE), PE-LLD (LLDPE), PE-HMW, as well as PE-UHMW. The polypropylene, polyphenylene sulfone, polyetherimide and polyether ketone which are suitable according to the invention are likewise known or can be prepared by processes known from the literature.

In general, it may be useful to add thermal stabilizers and flow improvers to the thermoplastic used for the matrix.

The fibers used according to the invention are in particular natural fibers or artificially produced fibers or a mixture of the two. The natural fibers are preferably fibrous

Minerals or vegetable fibers and the man-made fibers preferably inorganic synthetic fibers or organic synthetic fibers. Preferred according to the invention are glass, carbon or polymer fibers, again preferably glass fibers or carbon fibers.

Very particular preference is given to using glass fibers, in particular having an E-modulus of greater than 50 GPa, preferably greater than 70 GPa, or carbon fibers, in particular having an E-modulus of greater than 200 GPa, preferably greater than 230 GPa. In particular, carbon fibers having these properties are preferable. Such carbon fibers are known, for example, under the name Pyrofil from Mitsubishi Rayon CO., LtD. available in the stores.

The fiber volume content in the wetted sliver is from 30 to 70%, preferably from 35 to 60%, particularly preferably from 40 to 50% by volume.

The sliver wetted according to the invention is distinguished by the fact that it is at least externally surrounded by thermoplastic in a considered length section, on the other hand the deviation from the desired fiber volume content per width section is at most 5%, preferably at most 2%. In this case, the amount of the excess of thermoplastics which is necessary to bring about such wetting is at most 5%, preferably at most 3%, particularly preferably at most 1%, of the amount of thermoplastic, which in total for the wetting of a non-wetted fiber band is consumed, ie the amount that adheres in the impregnated sliver, increased by the amount of excess. Thus, it is not necessary to trim the impregnated sliver made from the wetted sliver to achieve the desired degree of impregnation.

As a material for the wetting nozzle in particular tempered tool steels are suitable, which can be machined well, for example, the steels 1.2311 or 1.2312.

The process according to the invention corresponds to the process described in WO 2012 123 302 A1, in particular the process described on page 1, line 26, to page 2, line 22, the wetting nozzle according to the invention being used in the process according to the invention.

From the wetted sliver, the impregnated fiber sliver can be obtained for example by pressurization, in turn, for example, by deflecting the sliver on a roll. The impregnated fiber sliver can preferably be obtained by pressure-shear vibration treatment in accordance with the method described in WO 2012 123 302 A1, in particular in the method described on page 11, line 23, to page 21, line 2, and the associated figures , Another object of the present invention is also an impregnated sliver that can be produced with the device according to the invention or the method according to the invention.

A typical impregnated sliver generally has a length of 100 to 3000 m, a width of 60 to 2100 mm, preferably of 500 to 1000 mm, particularly preferably of 600 to 800 mm, and a thickness of 100 to 350 μιη in the running direction , preferably from 120 to 200 μιη. However, a differently dimensioned impregnated fiber band can also be processed on the device according to the invention.

The impregnated fiber sliver according to the invention is characterized in that at least 90%, particularly preferably at least 95%, of the surface area of all the fibers of an impregnated sliver is impregnated with the thermoplastic used in each case. Further preferably, the degree of impregnation in each width section of the impregnated fiber sliver should differ by a maximum of 10%, preferably not more than 5%, particularly preferably not more than 2%, from the average degree of impregnation of the impregnated fiber sliver.

Such an impregnated fiber sliver according to the invention is particularly suitable for providing a multi-layer composite material which has an aesthetically pleasing surface with low waviness and at the same time good mechanical properties. Such a multi-layer composite material composed of impregnated fiber ribbons with polycarbonate as the matrix material has a metal-like feel, appearance and acoustics. With these properties, such a multilayer composite material is also suitable as a housing material for housings for electronic devices, in particular portable electronic devices such as laptops or smartphones, for the outer planking as well as for interior trim of automobiles, since such a multilayer composite material can absorb both mechanical load and an outstanding external appearance offers.

A further subject of the invention is therefore also a multilayer composite material produced from the impregnated fiber band according to the invention.

Fig. 1 shows in simplified form a section of the impregnating nozzle according to the invention with a semicircular wetting pocket, without the invention being limited to the illustrated embodiment.

Fig. 2 shows in simplified form a section of the impregnating nozzle according to the invention with a wetting pocket in the form of a 120 ° sub-circle with attached, pointed in the feed direction expiring triangle, without the invention being limited to the illustrated embodiment.

Here are:

1 wetting bag

2 Opening of the wetting slot

3 Width w of the opening of the wetting slot

4 feed direction

5 angle A

6 imaginary line to represent a leg of a leaking in the feed direction triangle

7 imaginary line for representing the base of an expiring in the feed direction expiring

Triangle 8 radius R

Claims

Claims:

A wetting nozzle with a wetting slot (2) for producing a thermoplastic-wetted fiber tape, characterized in that the wetting nozzle has two wetting pockets (1), wherein the wetting nozzle has a wetting pocket (2) at both horizontally lateral ends of the opening of the wetting slot (2). 1).

2. wetting nozzle according to claim 1, characterized in that the wetting pockets (1) in the plan view semicircular, semi-oval, or in the form of a partial circle with an angle A of 120 ° - 135 ° are formed with attached, in the feed direction tapered expiring triangle.

3. wetting nozzle according to claim 2, characterized in that the radius R of a wetting pocket (1) of 0.5 mm to 2 mm, preferably about 1 mm.

4. wetting nozzle according to one of claims 1 to 3, characterized in that it is made of a tempered tool steel.

5. wetting nozzle according to one of claims 1 to 4, characterized in that the wetting nozzle is composed of a plurality of mutually movable parts.

6. A process for the preparation of a wetted with thermoplastic fiber tape, characterized

in that a device according to one of claims 1 to 5 is used.

7. A process for the preparation of a thermoplastic impregnated fiber ribbon, characterized

characterized in that in a first step according to claim 6, a thermoplastic-wetted sliver is produced, and in a further step by

Pressurization or by pressure-Seher- Vibrationsbeaufschlagung a

Impregnation is performed by.

8. polymer-impregnated sliver, characterized in that at least 90%, more preferably at least 95% of the surface of all fibers with a

Thermoplastic impregnated slivers are impregnated with the thermoplastic used in each case.

9. Thermoplastically impregnated sliver according to claim 8, characterized in that the degree of impregnation in each width section of the impregnated fiber sliver deviates at most by 10%, preferably at most 5%, more preferably at most 2% from the average degree of impregnation of the impregnated sliver , Multilayer composite material produced from an impregnated fiber sliver according to claim 8 or 9.

Use of a multi-layer composite according to claim 10 for the outer skin and interior trim of automobiles and as housing material for housing for electronic devices, preferably portable electronic devices, more preferably laptops or smartphones.