Polymer Fibre

Abstract

A fibre comprising a colour component comprising an unencapsulated liquid crystal contained in the cavity of a hollow polymeric sheath is provided. The sheath retains the colour component and additional materials may be included to provide a tailored aesthetic effect. The fibre is useful as an artificial hair product and for weaving or knitting into a fabric.

Claims

1. A fibre comprising a self-supporting hollow polymeric sheath and, within the hollow sheath, a colour component comprising a liquid crystal providing a desired aesthetic effect wherein the self-supporting sheath imparts dimensional stability to the fibre.

2. A fibre according to claim 1 wherein the liquid crystal is an unencapsulated liquid crystal.

3. A fibre according to claim 1 wherein the liquid crystal provides a static colour.

4. A fibre according to claim 1 wherein the hollow polymeric sheath is transparent or translucent.

5. A fibre according to claim 1 wherein the hollow polymeric sheath comprises a thermoplastic polymer.

6. A fibre according to claim 1 wherein the hollow polymeric sheath is selected from nylon, modacrylic, polyamide, polyester, polyalkylene, a thermoplastic vulcanizate, a thermoplastic polyurethane a thermoplastic elastomer polymer, a synthetic rubber and a thermoplastic olefin.

7. A fibre according to claim 1 wherein the polymeric sheath comprises a further colour component.

8. A fibre according to claim 7 wherein the polymeric sheath comprises an encapsulated liquid crystal, a dye and/or a pigment as a dispersed phase.

9. A fibre according to claim 1 wherein the polymeric sheath is substantially free of components which impair the visual effect of the colour component in the cavity of the hollow sheath.

10. A fibre according to claim 1 wherein the colour component further comprises a further colour component selected from a dye and a pigment.

11. A fibre according to claim 1 wherein the colour component further comprises a dark colour component, preferably selected from carbon black and carbon nano tubes.

12. A fibre according to claim 1 wherein the colour component further comprises solid particles selected from silica particles, a mica, a precious material, and precious minerals.

13. A fibre according to claim 1 wherein the colour component further comprises a component which undergoes a solid/liquid phase change or softening at a temperature under 50° C.

14. A fibre according to claim 13 wherein the colour component is selected from gallium and wax.

15. A fibre according to claim 1 wherein the colour component further comprises particles to provide a refraction or prism effect.

16. An artificial hair product comprising a fibre, the fibre comprising a self-supporting hollow polymeric sheath and, within the hollow sheath, a colour component comprising a liquid crystal providing a desired aesthetic effect wherein the self-supporting sheath imparts dimensional stability to the fibre, the fibre having a diameter of 15 to 150 microns.

17. A fabric comprising a multitude of interlinked fibres, each fibre of the interlinked fibres comprising a self-supporting hollow polymeric sheath and, within the hollow sheath, a colour component comprising a liquid crystal providing a desired aesthetic effect wherein the self-supporting sheath imparts dimensional stability to the fibre.

18. A fabric according to claim 17 comprising at least one of natural and man-made fibres.

19. A garment or fabric product comprising a fabric, the fabric comprising a multitude of interlinked fibres, each fibre of the interlinked fibres comprising a self-supporting hollow polymeric sheath and, within the hollow sheath, a colour component comprising a liquid crystal providing a desired aesthetic effect wherein the self-supporting sheath imparts dimensional stability to the fibre.

20. A process for the production of a fibre, the fibre comprising a self-supporting hollow polymeric sheath and, within the hollow sheath, a colour component comprising a liquid crystal providing a desired aesthetic effect wherein the self-supporting sheath imparts dimensional stability to the fibre the process comprising feeding a polymer melt into an extrusion channel so as to produce an extruded hollow polymeric tube, feeding a flowable colour component comprising a liquid crystal into a zone within the hollow tube so as to fill the polymeric hollow tube whereby the polymer is extruded to form the sheath around the liquid crystal component thereby to form the fibre.

Description

EXAMPLES

[0057] Fibres according to the invention were prepared by passing a colour component through a dye with an outer coaxial zone for passage of the outer polymeric sheath. The outer polymeric sheath enclosed the colour component to produce a fibre according to the invention.

[0058] Fibres having the components listed in Table 2 were prepared and the colour component is referred to as the “core”. Where the colour component or outer layer comprised additional components to the liquid crystal or polymer respectively, the respective components were pre-mixed with the main component before extrusion. The polymer sheath was extruded at a draw speed of between 30 and 60 rpm and with an inlet/middle/outlet barrel temperature of 240-320/240-260/250-260. The colour component was introduce manually.

TABLE-US-00002 TABLE 2 Example Compone Ingredient Component Source Concentration 1 Core thermochromic LCR hallcrest 99 liquid crystal carbon black EMPEROR 1200 Cabot 1 Outer Polyurethane Elastollan B 85A 100 BASF 100 sheath 2 Core thermochromic LCR hallcrest 99 liquid crystal carbon black EMPEROR 1200 Cabot 1 Outer Nylon 6 Nylon 6 Natural BS10 A. Schulman 100 sheath 3 Core thermochromic LCR hallcrest 99 liquid crystal carbon black EMPEROR 1200 Cabot 1 Outer Polyurethane Elastollan B 85A 100 BASF 99 sheath UV Absorber Tinuvin 99-2 BASF 1 4 Core thermochromic LCR hallcrest 100 liquid crystal Outer Nylon 6 Nylon 6 Natural BS10 A. Schulman 98.5 sheath UV Absorber Tinuvin 99-2 BASF 1 Colourant Heliogen ® Blue D 70 BASF 0.5 5 Core thermochromic Phenyl benzoate ester LCR hallcrest 99.5 liquid crystal liquid crystal (75) and cholesteric liquid crystal (25%) Oil soluble black 0.5 dye Outer Polypropylene 99 sheath UV Absorber Tinuvin 99-2 BASF 1 6 Core thermochromic Phenyl benzoate ester LCR hallcrest 99.5 liquid crystal liquid crystal Oil soluble black 0.5 dye Outer Polypropylene 99 sheath 80%/LUCENE20 UV Absorber Tinuvin 99-2 BASF 1

[0059] The fibres were produced by extruding the polymer and the core component. All fibres were adequately formed and flexible and were suitable for processing into a yarn and weaving into a fabric.

[0060] On application of heat, the liquid crystal to change colour. Those examples containing solely nematic liquid crystal provided the greater vibrancy and intensity of colour change.

[0061] Examples 5 and 6 included an oil soluble dye in the liquid crystal which provided enhanced brightness of colour

Example 7

[0062] An artificial hair product comprising fibres produced in Example 2 was prepared, the fibres having a diameter of 40 to 120 microns. After production of the fibre, the fibre was dyed using a sublimation dye bath for 30 minutes, heated to a temperature of 80° C. The sublimation dye bath can be tuned to obtain any natural hair colour in the fibre, using different dilutions of black or brown dye. The artificial hair product in its initial state was a natural hair colour. On application of heat to provide a temperature change of less than 5° C., the colour component changed colour as a result of the liquid crystal changing state to provide a desirable aesthetic effect.