WO1997047795A1

WO1997047795A1 - Pressed felt

Info

Publication number: WO1997047795A1
Application number: PCT/GB1997/001539
Authority: WO
Inventors: Calvin Roger Woodings
Original assignee: Courtaulds Fibres (Holdings) Limited
Priority date: 1996-06-10
Filing date: 1997-06-09
Publication date: 1997-12-18
Also published as: TW333567B; GB9612058D0; AU3040197A

Abstract

A pressed felt comprises 10 to 50 percent by weight of animal hair and 20 to 90 percent by weight of lyocell staple fibre. The balance of the pressed felt, if any, is made up of other types of fibre. Such felts offer advantages in strength, stability and special effects in comparison with known felts which comprise animal hair and viscose rayon fibre.

Description

PRESSED FELT

Field of the invention

This invention relates to pressed felts, that is to say felts formed from a web or batt comprising animal hair and consolidated by the application of heat and mechanical action to cause the constituent fibres to mat together.

The animal hair used in the manufacture of felts, for example wool, in general has a surface scale structure When a mass of such hairs or fibres is subjected to the action of moisture, heat and varying pressure, the fibres interlock and become entangled into a compact mass. It is believed that the presence of the surface scales plays a fundamental role in the felting process, assisting in the required entanglement and consolidation. Felts may be made from mixtures of different types of animal hair or from mixtures of animal hair with other types of fibre in order to achieve a desired balance of properties. Animal hair is m general an expensive material, and thus felts have been made which comprise a blend of animal hair with cheaper materials such as viscose rayon staple fibre. Felts satisfactory for some purposes have been made containing as little as 30 percent by weight wool and as much as 70 percent by weight viscose rayon. Felts containing a higher proportion of viscose rayon have not, however, been found to possess satisfactory properties, in particular satisfactory mechanical properties. Objects of the present invention include the provision of felts which are cheaper to make and/or which have improved properties in comparison with those previously known.

Disclosure of invention

According to the present invention, there is provided a pressed felt characterised in that it comprises 10 to 50 percent by weight of animal hair and 20 to 90 percent by weight of lyocell staple fibre, with the balance (if any) being composed of other types of fibre or fibres. The felt may consist solely of animal hair and lyocell fibre, or it may additionally comprise one or more other types of fibre, for example viscose rayon staple fibre. A preferred felt according to the invention consists of animal hair and lyocell fibre in a weight ratio in the range from 50:50 to 10:90, more preferably from 30:70 to 15:85.

Lyocell fibre is known and may also be called solvent-spun cellulose fibre. It is made by extrusion of a solution of cellulose in an aqueous tertiary amine M-oxide solvent through a spmnerette into an aqueous coagulating bath, followed by washing and drying Lyocell fibre is available commercially from Courtaulds Fibres (Holdings) Limited.

It has surprisingly been found that a felt according to the invention consisting of 20 parts by weight wool and 80 parts by weight 3.3 dtex 63 mm lyocell staple fibre is stronger than a known type of felt consisting of 30 parts by weight wool and 70 parts by weight viscose rayon staple fibre and may be up to three times stronger in the machine direction. Furthermore, the extensibility of the wool/lyocell felt was less than that of the wool/viscose felt, resulting in increased stability. Still further, the wool/lyocell felt could be processed in a time about 20 percent shorter than the wool/viscose felt. Yet further, the wool/lyocell felt was observed to shrink on washing by as little as 5 percent in area, in comparison with a typical figure of 50 percent for the wool/viscose felt. On such washing, the wool/lyocell felt bulked up, due to shrinkage of the wool, to give a felt with an attractive cockled finish resembling astrakhan and having self-bonded edges. If desired, such cockling can be avoided by carrying out wet-processing operations, such as dyeing and washing, on a stenter frame. Durability to washing is a particular advantage of the felt of the invention. The lyocell fibre used to make the felt of the invention is preferably a matt fibre containing a dulling pigment such as titanium dioxide. The fibre preferably has a decitex in the range from 1 to 10 and a staple length in the range from 30 to 150 mm.

The basis weight of a felt according to the invention is generally in the conventional range for pressed felts. It is often in the range from 100 to 1000 g/rrr for a felt sheet.

The felt of the invention may also take the form of a block, for example up to 15 cm thick, for industrial processing.

Felt according to the invention may be made using conventional equipment. It is known that lyocell fibre fibrillates under wet-processing conditions. It has surprisingly been found that lyocell fibre does not necessarily fibrillate to any great extent during the manufacture of felt according to the invention, so providing a felt with a smooth and shiny surface.

Felt according to the invention may be used, for example, m hobby, toy, fancy dress and display applications.

The invention is illustrated by the following Examples, in which parts and proportions are by weight unless otherwise specified: -

EXAMPLES

Pressed felts A, B and C were made in conventional manner from a blend of 70 parts lyocell fibre and 30 parts wool. A control felt was made from 70 parts viscose rayon and 30 parts wool. The results shown in Table 1 were obtained:- -J

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MD machine direction; CD = cross direction. -r-»

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The tensile results are the averages of tests on five strips of material and are normalised to basis weight 150 g/m² for ease of comparison between samples .

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Claims

1. A pressed felt, characterised in that it comprises 10 to 50 percent by weight of animal hair and 20 to 90 percent by weight of lyocell staple fibre, with the balance (if any) being composed of other types of fibre or fibres.

2. A pressed felt according to claim 1, characterised in that it consists of animal hair and lyocell staple fibre in a weight ratio in the range from 50:50 to 10:90.

3. A pressed felt according to claim 2, characterised in that it consists of animal hair and lyocell staple fibre m a weight ratio in the range from 30:70 to 15:85.