Method for producing a textile unidirectional fabric
Method for producing a textile unidirectional fabric, wherein at least one planar layer of multi-filament reinforcement threads arranged parallel to each other are woven with each other over transverse threads, wherein transverse threads having core-sheath structure and titer of 10 to 40 tex are used as transverse threads, wherein transverse threads have a first component, which structures sheath, and second component, which structures core, wherein first component has lower melting temperature than second component, first component is meltable thermoplastic polymer material and, via first component of transverse threads, adjacently arranged multi-filament reinforcement threads are connected to each other by hot melting, wherein alleys are formed in unidirectional fabric by interweaving multi-filament reinforcement threads together with transverse threads, by means of which a permeability of 10 to 600 l/dm2/min can be established. Preferred embodiment relates to method for producing unidirectional fabric having fleece. Further, a fiber preform, produced from unidirectional fabric.
1. A method for producing a textile unidirectional fabric, wherein at least one flat layer of mutually parallel juxtaposed multifilament reinforcement threads is interwoven with transverse threads, wherein the transverse threads comprise a core-sheath structure, wherein the transverse threads comprise a first component constituting the sheath and a second component constituting the core, wherein the first component has a lower melting temperature than the second component, and wherein the first component is a meltable thermoplastic polymer material, and wherein the first component of the transverse threads is bonded together with the juxtaposed multifilament reinforcement threads by melt bonding, the transverse threads having a linear density of 10 to 40 tex, measured according to EN ISO 2060: 1995, and wherein the textile unidirectional fabric comprises alleys that provide a permeability of 10 to 600 l/dm 2 /min, measured according to EN ISO 9237.
2. The method according to claim 1 , wherein a non-woven of thermoplastic polymer material is arranged on and is adhesively bonded to the at least one flat layer of the multifilament reinforcement threads.
3. The method according to claim 2 , wherein the non-woven has a basic weight in the range of 3 to 25 g/m 2 .
4. The method according to claim 2 , wherein the non-woven has a thickness, measured perpendicular to a propagation direction of the non-woven, of less than 60 μm, measured according to DIN ISO 9073-2.
5. The method according to claim 2 , wherein the non-woven comprises a first polymer component and a second polymer component, wherein the first polymer component has a melting temperature below the melting or decomposition temperature of the second component of the transverse threads and is not soluble in matrix resins of epoxy, cyanate ester, or benzoxazine or mixtures of these matrix resins, wherein the second polymer component has a lower melting temperature than the first polymer component.
6. The method according to claim 1 , wherein the permeability is more than 25 l/dm 2 /min, and/or the alleys are substantially formed only in an area of binding points of the interwoven of the multifilament reinforcement threads and transverse threads.
7. The method according to claim 1 , wherein the transverse threads are woven with the multifilament reinforcement threads to form the textile unidirectional fabric in a twill or plain weave.
8. The method according to claim 7 , wherein a twill weave 3/1 with 0.8 to 3.0 Fd/cm, a twill weave 3/1 with 0.8 to 3.0 Fd/cm, a twill weave 2/1 with 0.8 to 3.0 Fd/cm, a plain weave 1/1 with 0.8 to 3.0 Fd/cm and/or a plain weave 1/1 with 0.8 to 3.0 Fd/cm, is used for interweaving the transverse threads with the multifilament reinforcement threads.
9. The method according to claim 1 , wherein a component having a melting temperature in the range of 70 to 150° C. is used for the first component of the transverse threads.
10. The method according to claim 9 , wherein the first component of the transverse threads is a polyamide homopolymer or polyamide copolymer, or a mixture of polyamide homopolymers and/or polyamide copolymers.
11. The method according to claim 1 , wherein a component with a melting temperature above 200° C. is used as the second component of the transverse threads.
12. The method according to claim 1 , wherein glass or a polyester is used as the second component of the transverse threads.
13. The method according to claim 1 , wherein the transverse threads have a titer in the range of 15 to 35 tex, measured according to EN ISO 2060: 1995.
14. The method according to claim 1 , wherein carbon fibre, glass fibre' aramid threads, or ultra-high molecular weight (UHMW) threads are used as the multifilament reinforcement threads.
15. The method according to claim 1 , wherein the multifilament reinforcement threads comprise a carbon fibre thread having a strength of at least 5000 MPa measured according to JIS R-7608 and a tensile modulus of at least 260 GPa, measured according to JIS R-7608.
16. The method according to claim 1 , wherein the at least one flat layer of mutually parallel juxtaposed multifilament reinforcement threads has a curved contour, in which the multifilament reinforcement threads are arranged parallel to a circumferential direction of the curved contour, and wherein and each of the multifilament reinforcement threads follows the circumferential direction of the curved contour, while trajectories of the multifilament reinforcement threads have a common centre of curvature.
17. A fibre preform for production of composite components, wherein the fibre preform comprises a textile unidirectional fabric prepared according to claim 1 .