GB2263241A - Upholstery fabric - Google Patents

Abstract

An improved upholstery fabric is made by knitting a fabric, particularly in cotton yarn, so as to have protruding loops of the same or different composition, e.g. polyacrylic yarn, and thereafter coating the other side with a polymerizable fire-retardance material, e.g. acrylic polymer latex and allowing it to coagulate to a surface layer which is fire-retardant and renders the fabric suitably dimensionably stable.

Description

IMPROVED UPHOLSTER? FABRIC This invention relates to an improved upholstery fabric of enhanced flame retardance.

Such fabric is potentially of general application as an upholstery fabric. It is of particular application to the upholstery of divider panels in open plan offices and like environments. For ease of description it will therefore be described in relation to such panels except where otherwise indicated.

Office divider screens are typically a flat framework clad on both sides with a suitably coloured and textured upholstery for pleasing appearance and wear. Because the upholstery is applied over a large area, there is a requirement that it should be stable in dimension when cut and applied. Because of this it has been conventional to make such structures as woven structures, typically of a wool and viscose mixed yarn and of a single structure warp and weft. Depending upon the fibre used there may be some flame retardancy inherent in such structures, but many forms of such woven material possess only temporary flame retardancy if any.

It is moreover noteworthy that such fabric possess only a limited range of dyeability characteristics so that there can be a problem of colour compatibility with the required decoration scheme.

The present invention sets out to overcome the problems of flame retardancy and of dyeability while presenting a stable structure for upholstery of the relatively large flat surfaces of divider screens.

In one aspect the invention consists in a knitted fabric for use in upholstery, incorporating yarn loops at one surface and having coated over the other surface a flame retardance material of a nature which also provides dimensional stability to the fabric.

Preferably the knitted fabric is of cotton yarn, although other materials are possible. Preferably the loops are of a different nature, such as a polyacrylic yarn. It is valuable if the knitted fabric is chosen to have some inherent flame retardancy, even though flame retardancy is in accordance with the invention is conferred by a separate coating procedure.

It is especially preferably in accordance with the invention if the knitted fabric, and/or the protruding loops have ready dyeability characteristics over a range of colours. White cotton yarn is particularly valuable for the fabric to achieve this purpose.

The flame retardance material, when applied to the knitted yarn surface is preferably a water-based latex.

A latex of an acrylic polymer is valuable, and appears to coagulate in such a way that it provides not only the flame retardant properties but the necessary dimension-stabilising properties for the knitted fabric.

There is thus produced according to the invention an upholstery material which is readily dyeable to a range of colours, and which although a knitted material is suitably dimensionally stable to constitutes areas of upholstery on a structure.

In another aspect therefore the invention consists in a upholstered article having a surface layer of fabric as defined above, more especially when the article is in the form of an office divider screen.

To carry one embodiment of the invention into practice, a spun cotton yarn is unformly knitted. The fabric produced has to some extent useful inherent flame retardant properties, and in particular provides even when charred a resistant structure. That is to say, it is not prone to flame up and disappear at the approach of an igniting flame.

The knitting process being is carried upon a circular knitting machine of suitable dimensions, knitted in with the cotton yarn is a looped material the loops of which project from one face of the knitted fabric structure. The loops are typically composed of polyacrylic fibres, and can be so configured as to provide a modicum of flame retardation.

Such a knitted structure, when presented as a relatively large panel would, in itself not be of adequate dimensional stability for the upholstery purpose intended.

The procedure of the invention envisages using a spreading knife or its equivalent to apply a back coating of a latex material, water based, and probably acrylic in nature. A typical material is available under the trade name "FR LATEX" from British Tar,.

Mydrin, Barnsley. This latex is spread over the knitted cotton side of the fabric, and sets to a layer which is not only flame retardant but also dimensionally stabilises the woven fabric. Such a product is capable of passing BS 476, which is a screen fabric test and BS 5852 part 2 crib 5 which is a general upholstery test.

The latex coating weight lies preferably between 60 and 120 gms/nt2. Below 60 gms/m2 there is more danger of loss of dimensional stability, and above 120 gms/m2 the material, although of good flame gms/m resistance, tends to become stiffer and less flexible.

About 70 gms/m2 is a suitable value for a wide range of fabrics.

The yarn count range i. e. the thickness of the yarn, is widely variable in the practice of the invention, and we have used, by way of example, yarn counts from a maximum thickness of 6s nm to a minimum of 60s nm. The knit size, in needles per inch, is also variable, from for example, 40 to 70: a specific example of 52 needles per inch has been used.

A feature of the invention is the dyeability of the fabric. Because the fabric is of a composite nature, with acrylic loops projecting from one face of a cotton knit (by way of example) it will dye to different extents in different places. The invention also envisages subjecting the fabric to successive dyeing processes, so that different faces of the fabric possess different colours or different shades of the same colour. The wide range of acceptable colours which can be achieved on a knitted cotton yarn base is considerably greater than the range of colours and colour mixtures available in accordance with the prior art.

Various modifications can be made within the scope of the invention. For example, while cotton is a preferred yarn to be knitted as the backing material, wool, worsted, or manmade yarns or blends thereof can also be used. It is however desirable to use on yarn which has a good char structure under the effect of flame, even though there is a subsequent flame retardant treatment by means of the latex.

Similarly, the fibre constituting the loop on the front surface, while indicated above as an polyacrylic fibre can alternatively be wool or worsted or a manmade fibre or blends thereof. Loop size is another variable in the process and product, acting to alter the texture of the material, and is controlled by tension gauges at the yarn stage prior to knitting.

Claims (10)

CLAIMS:

1. A knitted fabric for use in upholstery, incorporating yarn loops at one surface and having coated over the other surface a flame retardance material of a nature which also provides dimensional stability to the fabric.

2. A knitted fabric as claimed in claim 1 comprising cotton yarn.

3. A knitted fabric as claimed in claim 1 or 2 in which the loops comprise a polyacrylic yarn.

4. A knitted fabric as claimed in claim 1, 2 or 3 in which the surface coating to confer fire-retardant properties comprises a coagulated acrylic polymer.

5. A method of producing an upholstery fabric which a first yarn is knitted to form a fabric with incorporation of a second yarn knitted to provide loops extending from one surface of the said fabric; a polymerisable flame-retardance material is spread over the other surface of the fabric; and the polymerisable material is caused or allowed to polymerise to give a flame-retardant surface which dimensionally stabilises the knitted fabric.

6. A method as claimed in claim 5 in which one or more dyeing stages are incorporated to act upon the coated or uncoated fabric and/or protruding loops.

7. A method as claimed in claim 5 or 6 in which the yarn for knitting has a thickness from 6s nm to 60s nm; the knit size is from 40 to 70 per inch; and the polymerised coating weights between 60 and 120 gms/m2.

8. A flame-retardant upholstery fabric produced by the method claimed in claim 5, 6 or 7.

9. An upholstered article having a surface layer of fabric as claimed in any one of claims 1 to 4, or 8.

10. An upholstered article as claimed in claim 9 in the form of an office divider screen.