ALTERNATIVE EXTERIOR TRIM PART

Abstract

An exterior trim part for a vehicle comprises a fibrous porous structural layer. The fibrous porous structural layer consists of staple fibres, only. At least 50%, preferably between 70% and 100%, of the staple fibres comprise a first polymer made of modified polyester, such as CoPET, with a melting temperature between 150 C. and 240 C., preferably between 190 C. and 240 C.

Claims

1. An exterior trim part for a vehicle, with a fibrous porous structural layer, wherein the fibrous porous structural layer consists of staple fibres, wherein at least 50%, preferably between 70% and 100%, of the staple fibres comprise a first polymer made of modified polyester, such as CoPET, with a melting temperature between 150 C. and 240 C., preferably between 190 C. and 240 C.

2. The exterior trim part according claim 1, wherein the first polymer forms sheaths of at least 50%, preferably between 70% and 100%, of the staple fibres.

3. The exterior trim part according to claim 1, wherein at least 50%, preferably between 70% and 100%, of the staple fibres comprise a second polymer made of PET with a melting temperature of at least 240 C., preferably wherein the second polymer forms cores of said staple fibres.

4. The exterior trim part according to claim 1, wherein up to 50% of the staple fibres consist of PET with a melting temperature of at least 240 C.

5. The exterior trim part according to claim 1, wherein the fibrous porous structural layer comprises at least 50%, preferably between 70 and 100%, first bicomponent staple fibres, the sheaths of which consist of the first polymer and their cores consist of the second polymer.

6. The exterior trim part according to claim 1, wherein at least 10%, preferably between 20% and 60%, of the staple fibres comprising the first polymer consist of the first polymer.

7. The exterior trim part according to claim 1, wherein some, preferably the rest, of the staple fibres of the fibrous porous structural layer consist of the second polymer or are said first bicomponent staple fibres.

8. The exterior trim part according to claim 1, wherein the fibrous porous structural layer comprises a) said first bicomponent staple fibres, and b) second bicomponent staple fibres, the sheaths of which with a melting temperature of at least 20 C. lower than the melting temperature of the sheaths of the first bicomponent staple fibres, wherein the first and second bicomponent staple fibres form at least 15%, preferably between 20% to 40%, of the fibrous porous structural layer, and preferably staple fibres consisting of the second polymer.

9. The exterior trim part for a vehicle, with a fibrous porous structural layer, wherein the fibrous porous structural layer, consists of staple fibres, wherein at least 15%, preferably between 20% and 40%, of the staple fibres consist of a first polymer made of modified polyester, such as CoPET, with a melting temperature between 150 C. and 240 C., preferably between 190 C. and 240 C., wherein the rest of the staple fibres of the fibrous porous structural layer consist of a second polymer made of PET with a melting temperature of at least 240 C.

10. The exterior trim part according to claim 1, comprising at least one perforated film layer, which is made of thermoplastic polyurethane with a melting temperature according to Differential Scanning calorimetry (DSC) of at least 140 C. and which is materially connected to said fibrous porous structural layer.

11. The exterior trim part according to claim 10, wherein the thermoplastic polyurethane film is based on polyether or polyester.

12. The exterior trim part according to claim 1, wherein the exterior trim part has a total thickness between 1.5 and 10 mm and has an airflow resistance (AFR) in the direction of thickness between 1,000 to 4,500 N.Math.s/m.sup.3.

13. The exterior trim part according to claim 10, wherein the film is only partially perforated.

14. The exterior trim part according to claim 10, wherein the film layer is not perforated but air permeable.

15. Th exterior trim part according to claim 10, with a scrim layer which is, in particular materially, connected to the film layer.

16. Use of an exterior trim part according to claim 1 as an engine bay covering panel, a top-, side- or undercover for an engine, an oil pan cover, an under engine shield, a fire wall, an at least partially covering outer dash panel, an air guiding panel behind the cooler of the engine bay or a vehicle's underbody covering panel, an outer wheel arch liner, a hush panel or as an automotive exterior trim part.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0106] Further advantages, features and applications of the present invention become apparent from the following description referring to the figures, showing.

[0107] FIG. 1a to 1c schematically show cross sections of preferred developments of the exterior trim part,

[0108] FIG. 2 a plot of sound absorption.

[0109] FIG. 3 shows a drawing of the underside of a car.

[0110] FIG. 1a shows an exploded view of the exterior trim part 1 according to a preferred development. The thicknesses of the layers are not drawn to scale. The fibrous porous structural layer 2 is connected with the perforated film layer 3.

[0111] FIG. 1b shows a preferred development of the exterior trim part 1. The thicknesses of the layers are not drawn to scale. This exterior trim part 1 has a scrim layer 4. The film layer 3 is arranged between the fibrous porous structural layer 2 and the scrim layer 4. The scrim layer 4 is materially connected to the film layer 3. The scrim layer 4 serves to protect the film layer 3 and to simplify the removal of the exterior trim part 1 from a mould during manufacturing.

[0112] FIG. 1c shows a further preferred development of the exterior trim part 1. The thicknesses of the layers are not drawn to scale. This exterior trim part 1 has a heat reflective layer 6. The film layer 3 is arranged between the fibrous porous structural layer 2 and the heat reflective layer 6. The heat reflective layer 6 is materially connected to the film layer 3.The heat reflective layer 6 is designed with one or several patches 6a, 6b which are arranged to face hot parts of a vehicle, such as the exhaust.

[0113] FIG. 2 shows a plot of sound absorption [] depending on the frequency. The dashed line shows the fibrous porous structural material without the film layer (reference). The solid line shows the fibrous porous structural layer with the film according to the invention (invention). The average AFR of the reference was measured as 646 N.Math.s/m.sup.3. The average AFR of the invention was measured as 2,120 N.Math.s/m.sup.3. When measuring the sound absorption, the microphone was located on the film side of the exterior trim part. The fibrous porous layer of the tested specimens had a nominal area weight of 1,000 g/m.sup.2 and the nominal thickness of the specimens was 4 mm. By using fibrous porous structural layer together with the film layer according to the invention the sound absorption was significantly improved within the range shown.

[0114] FIG. 3 shows a drawing of the underside of a car. The exterior trim part according to the invention can be used for example as under engine shield 7 or as panelling under the main floor, also known as under-body panel 8. Preferably, the exterior trim part for instance the underbody panel 8 can be divided in more than one part to enable a better handling or optimise on transport.

REFERENCE SIGN LIST

[0115] 1 exterior trim part

[0116] 2 fibrous porous structural layer

[0117] 3 film layer

[0118] 4 scrim layer

[0119] 6 heat reflective layer

[0120] 7 under engine shield

[0121] 8 underbody panel