GB2542333A

GB2542333A - A method of forming a fire retardant fabric Without the need to apply a fire retardant composition

Info

Publication number: GB2542333A
Application number: GB1514816.6A
Authority: GB
Inventors: Collinge David; Kenneth Dowen Mark
Original assignee: John Spencer (textiles) Ltd; So4bed Ltd
Current assignee: John Spencer (textiles) Ltd; So4bed Ltd
Priority date: 2015-08-20
Filing date: 2015-08-20
Publication date: 2017-03-22
Anticipated expiration: 2035-08-20
Also published as: GB201514816D0; GB2542333B

Abstract

A method of making a piece of furniture with a fire retardant fabric is disclosed. Firstly the fabric is formed by weaving a plurality of yarns. At least one first yarn is made from predominantly cotton fibres and at least one second yarn is made from predominantly wool fibres. Preferably the cotton forms the warp and the wool is the weft. A mixed yarn of both cotton and wool may also be used. Ideally, the fabric comprises 70-75% by weight of cotton and 25-30% by weight of wool, with an area weight between 200-500 g/m2. A frame or substrate of the furniture is also formed and the fabric can be used to at least partially cover the frame or substrate. This forms an item of furniture which passes the standard fire retardancy tests without the addition of undesirable chemical fire retardant compositions.

Description

A method of forming a fire retardant fabric without the need to apply a fire retardant composition

The present invention relates to a method of forming a fire retardant fabric whilst eliminating the need to apply a fire retardant composition to the fabric so formed and relates particularly, but not exclusively, to a method of forming a fire retardant predominantly natural fibre fabric for use in the construction of furniture and the like.

It has for many years been necessary in many countries, through consumer pressure and legislative requirements, to construct furniture using fire retardant fabrics. For predominantly natural fibre fabrics this is generally achieved by creating the fabric in the normal fashion and then by applying a fire retardant composition to the fabric so formed. The fire retardant properties of this fabric are then tested by using standard tests. These tests include the application of a naked flame to the fabric and determining how long it takes for the flames to go out and for the fibres to stop smouldering. For example, a, so called, match test is generally done by applying a gas probe or burner to the surface of the fabric for a predetermined period of time. An alternative is the CRIB test, and more specifically known as CRIB 5, where a small pyramid pile of wood approximately 2-3 inches high is placed onto the fabric and ignited.

The use of the fire retardant compositions presents a number of problems. For example, consumers generally prefer to avoid having articles in their homes with significant quantities of chemicals applied to them. This is particularly the case for articles such as mattresses and sofas which a person lying and sitting thereon will be in contact with for many hours a day, often for several years, whilst breathing air in very close proximity to the mattress. Furthermore, the application of the fire retardant compositions to the fabric is expensive and time-consuming for the manufacturer. For example, many of the fire retardant compositions are hazardous and toxic and therefore require significant safety precautions and procedures to be undertaken when handling the compositions. Furthermore, expensive machinery for the application of the compositions is required in order to safely spray, backcoat or impregnate the composition on to the fabric.

The application technique known as back-coating is the application of a coating of fire retardant composition on to the back of the fabric. This technique suffers from the disadvantage that the back-coating composition breaks down and falls off the material over time migrating, as particles, through the fabric and into the home environment. As a result of this degradation of the back-coating, the fire retardant properties of material are compromised over time. In addition back-coating is also sticky which means that silicon spray (which is itself inflammable) is often used to pull the fabric cover, and to stick the cover, in place. Disposal of articles which have been treated with fire retardant chemicals also presents a problem. New regulations to be introduced in Europe, referred to as REACH regulations, are due to come in force in 2017 on disposal of fire chemicals and will restrict the manner in which the items of furniture are disposed of. As a result, if the facilities for disposal of such articles of furniture treated with the retardant chemical product are not available (as is the case presently in the UK) they must be incinerated at a very high temperature .

Preferred embodiments of the present invention seek to overcome the above described disadvantages of the prior art. In particular, the present invention seeks to provide a method of forming a fabric which meets the requirements of fire safety tests without the need to apply fire retardant compositions thereto .

According to an aspect of the present invention there is provided a method of making a piece of furniture comprising the steps : - forming a fabric by weaving using a plurality of yarns, at least one first yarn comprising predominantly cotton fibres and at least one second yarn comprising predominantly wool fibres; forming a frame or substrate of the furniture; and at least partially covering the frame or substrate using the fabric .

Forming a fabric used in the manufacture of furniture by combining woven yarns of cotton and wool provides a fire retardant fabric, that is, a fabric capable of passing fire retardancy tests, without the addition of one or more fire retardant compositions. Indeed, the product has greater fire retardancy than most chemically treated products, achieving contract or CRIB 5 standards. Furniture formed using such a fabric has significant advantages both for the fabric manufacturer and for the furniture consumer. In particular, for the furniture manufacturer there is a reduction in cost. The processes of forming the fabric using a combination of cotton and wool yarns is significantly reduced because the hitherto necessary steps of applying a fire retardant composition to the fabric are removed thereby reducing the complexity and cost of the manufacturing machinery and the time required to apply the fire retardant composition to the fabric. Costs are further reduced by the removal of the material cost of the fire retardant composition. Furthermore, the safety aspects relating to the toxicity of the fire retardant compositions when handling large volumes are also removed. This makes the manufacturing process safer and reduces costs further by removing the need for safety apparatus associated with the safe handling of the fire retardant composition.

For the furniture consumer the advantages include a reduction in the cost of the furniture and a reduction in the chemicals being brought into the home. Very limited research work has been undertaken in assessing the long-term effects of bringing these chemicals into the home environment. It is therefore particularly beneficial to consumers who are concerned about the effects these chemicals are having on their health especially as no alternative to the application of the chemical fire retardant is available. Furthermore, the combination of cotton and woollen yarns provides the tactile aesthetic advantage that a fabric so produced is almost indistinguishable from a pure cotton fabric to the touch thereby avoiding the potential discomfort associated with predominantly wool fabrics.

The fabric produced by the method of the present invention is fire retardant over the product's lifetime and beyond as there is no composition which has been applied and which can degrade over time. Furthermore, there are no disposal problems since the fabric, and furniture built using the fabric, have not been treated with any chemical on which disposal regulations apply.

According to another aspect of the present invention there is provided a method of forming a fire retardant material without the hitherto necessary step of applying a fire retardant composition to the fabric, yarn or fibres, comprising the steps : - forming a fabric by weaving using a plurality of yarns, at least one first yarn comprising predominantly cotton fibres and not comprising a fire retardant composition applied thereto and at least one second yarn comprising predominantly wool fibres.

According to a further aspect of the present invention there is provided a method of forming a fire retardant material without the hitherto necessary step of applying a fire retardant composition to the fabric, yarn or fibres, comprising the steps : - forming a fabric by weaving using a plurality of yarns, at least one first yarn comprising predominantly cotton fibres and not comprising a fire retardant composition applied thereto and at least one second yarn comprising predominantly wool fibres.

In a preferred embodiment the first (cotton) yarn is used in a warp of the fabric and said second (wool) yarn is used in a weft of the fabric.

By using the cotton yarn as the warp and the wool yarn as the weft the advantage is provided that the fabric so formed is easily provided with cotton yarn on the outer surface of the fabric and the wool substantially covered by the cotton. As a result, the coarser fibres of the wool are not less present on the outer surface of the fabric and on the furniture on which it is used in turn making the furniture more comfortable to the touch.

The method may further comprise not applying a fire retardant composition to the fabric, or to the yarn forming the fabric, or to the fibres forming the yarn.

The resultant fabric preferably comprises between 50% cotton 50% wool and 75% cotton 25% wool.

The resultant fabric more preferably comprises between 60% cotton 40% wool and 75% cotton 25% wool.

The resultant fabric most preferably comprises between 70% cotton 30% wool and 75% cotton 25% wool.

The resultant fabric preferably comprises an area weight of between 100g/m2 and 900g/m2.

The resultant fabric more preferably comprises an area weight of between 150g/m2 and 700g/m2.

The resultant fabric preferably comprises an area weight of between 150g/m2 and 500g/m2.

The resultant fabric more preferably comprises an area weight of between 200g/m2 and 500g/m2.

The resultant fabric preferably comprises a number of warp yarns per inch between 50 and 100 and a number of weft yarns between 25 and 70.

The resultant fabric more preferably comprises a number of warp yarns per inch between 70 and 100 and a number of weft yarns between 35 and 60.

The resultant fabric preferably comprises a resultant yarn count of the warp yarn between Nm 15 and Nm 55 whilst a resultant yarn count of the weft is between Nm 10 and Nm 40.

The resultant fabric more preferably comprises a resultant yarn count of the warp yarn between Nm 15 and Nm 30 whilst a resultant yarn count of the weft to be between Nm 15 and Nm 30.

According to another aspect of the present invention there is provided a method of forming a fire retardant material without the hitherto necessary step of applying a fire retardant composition to the fabric, yarn or fibres, by forming a fabric from yarns comprising a combination of cotton and wool fibres.

Preferred embodiments of the present invention will now be described, by way of example only, and not in any limitative sense .

The fire retardant fabric described herein is most preferably used in the manufacture of furniture but can be used for other purposes as well. The term furniture, in the context of this application, is taken to mean any movable article that is used to equip a room or house for living in and which includes a woven fabric component, that is, upholstered furniture sometimes referred to as soft furnishings. A legal definition of furniture taken from the United Kingdom Furniture and Furnishings (Fire) (Safety) Regulations 1988, which can be regarded as a minimum definition of furniture and is not limiting, is as follows: (a) furniture of any description which is ordinarily intended for private use in a dwelling and includes beds and divans (including the bases and headboards of both), sofa-beds, children's furniture, cots (including carry-cots, playpens, prams and pushchairs and any other article of a like nature and use designed to contain a baby or small child), cushions, high-chairs, mattresses (of any size) and pillows, but does not include bedding or floor coverings (including carpets and mats); (b) furniture which is ordinarily intended for private use in the open air but which is also suitable for use in a dwelling; and (c) any collection of components designed or intended to be assembled into any article of furniture defined in subparagraphs (a) and (b) above. A non-exhaustive list of examples includes chairs, sofas and other seating, pillows and cushions, beds including mattresses and the like mattress toppers, throws, baby products for example car seats and clothing and the like.

The furniture is constructed by separately forming a fabric by weaving, forming a frame or substrate of the furniture and then applying the fabric to at least partially cover the frame or substrate. The formation of the frame or substrate uses standard furniture production techniques which will be familiar to person skilled in the art. For example, a seat or sofa is formed by constructing a frame from wood and/or metal and attaching to that a padding material, such as foam springs, polyester, 270g polyester fibre, felt or wool. Onto this the fabric is then applied to generally cover the majority of the frame and all of the padding material. For a mattress, a base frame of the mattress is formed from foam, latex and/or springs and the fabric is used to cover this mattress frame. For pillows and cushions the substrate is the filling of the cushion which may be foam, feathers or any other suitable filling material and the fabric covers this filling material. In practice the method of formation is to insert the filling into an outer cover but the end effect is the same as other furniture with a fabric covering a substrate.

The fabric is formed using known weaving techniques which employ a plurality of yarns, one of the yarns forming the weft and the other forming the warp. The yarns used in the weaving include at least one first yarn formed from predominantly, or preferably completely from, cotton fibres and a least one second yarn formed from predominantly, or preferably completely from, wool fibres. It is also preferable that the cotton yarn is used as the warp of the fabric and the wool yarn is used as the weft.

The composition of the fabric is such that it is preferably between 50% cotton 50% wool and 75% cotton 25% wool and more preferably between 60% cotton 40% wool and 75% cotton 25% wool. Most preferably the composition of the fabric is between 70% cotton 30% wool and 75% cotton 25% wool. Furthermore, the area weight should preferably be between 100 g/m2 and 900 g/m2 and more preferably between 150 g/m2 and 700 g/m2 or even between 150 g/m2 and 500 g/m2. Most preferably the area weight should be between 200 g/m2 and 500 g/m2. The composition of the fabric is such that the number of warp yarns per inch is preferably between 50 and 100 and the number of weft yarns is between 25 and 70 and most preferably the number of warp yarns per inch is between 70 and 100 and the number of weft yarns is between 35 and 60. Furthermore, the resultant yarn count of the warp yarn should preferably be between Nm 15 and Nm 55 whilst the resultant yarn count of the weft should preferably be between Nm 10 and Nm 40 and most preferably should be between Nm 15 and Nm 30 (warp) and between Nm 15 and Nm 30 (weft).

When a fabric is first formed a small sample is tested using known fire retardancy tests. For example, a naked flame is applied to the surface of the fabric for a predetermined period of time. This is generally sufficient for the fabric to ignite. However, when the applied flame is removed the flame emanating from the fabric of the present invention quickly goes out. This would also happen with a pure cotton fabric, although not as quickly, since cotton does not effectively maintain a flame. However, pure cotton would fail a fire retardancy test because the cotton threads will continue to smoulder for a significant period of time. In the fabric resulting from the method of the present invention the presence of the wool yarn adjacent the cotton yarn in the woven fabric causes the smoulder rate of the cotton yarn to significantly decrease meaning that the cotton yarn is unable to maintain its smoulder and goes out. As a result, the fabric comfortably passes the fire retardancy test as the flame and smoulder are not maintained for very long after the naked flame is been removed. It should be noted that it is extremely unexpected that such a fabric formed from natural materials, containing such a high proportion of cotton and untreated with fire retardant compositions, should be able to pass a fire retardancy test, in particular where the proportion of wool in the fabric is as low as 25%.

It will be appreciated by persons skilled in the art that the above embodiments have been described by way of example only and not in any limitative sense, and that various alterations and modifications are possible without departure from the scope of the protection which is defined by the appended claims. For example, other methods of forming the fabric, other than weaving, may be used such as knitting and non-woven techniques such as stitch-bonding and needle-punching. Furthermore, instead of using separate wool and cotton yarns a yarn formed from a combination of wool and cotton fibres may also be used.

Claims

1. A method of making a piece of furniture comprising the steps : - forming a fabric by weaving using a plurality of yarns, at least one first yarn comprising predominantly cotton fibres and at least one second yarn comprising predominantly wool fibres; forming a frame or substrate of the furniture; and at least partially covering the frame or substrate using the fabric .

2. A method of forming a fire retardant material without the hitherto necessary step of applying a fire retardant composition to the fabric, yarn or fibres, comprising the steps :- forming a fabric by weaving using a plurality of yarns, at least one first yarn comprising predominantly cotton fibres and not comprising a fire retardant composition applied thereto and at least one second yarn comprising predominantly wool fibres.

3. A method of forming a fire retardant fabric comprising the steps : - forming a fabric by weaving using a plurality of yarns, at least one first yarn comprising predominantly cotton fibres and at least one second yarn comprising predominantly wool fibres.

4. A method according to any of claims 1 to 3, wherein said first yarn is used in a warp of the fabric and said second yarn is used in a weft of the fabric.

5. A method according to any of claims 1, 3 or 4 further comprising not applying a fire retardant composition to the fabric, or to the yarn forming the fabric, or to the fibres forming the yarn.

6. A method according to any of claims 1 to 5, wherein said resultant fabric comprises between 50% cotton 50% wool and 75% cotton 25% wool.

7. A method according to any of claims 1 to 5, wherein said resultant fabric comprises between 60% cotton 40% wool and 75% cotton 25% wool.

8. A method according to any of claims 1 to 5, wherein said resultant fabric comprises between 70% cotton 30% wool and 75% cotton 25% wool.

9. A method according to any of claims 1 to 8, wherein said resultant fabric comprises an area weight of between 100g/m2 and 900g/m2 .

10. A method according to any of claims 1 to 8, wherein said resultant fabric comprises an area weight of between 150g/m2 and 7 00g/m2 .

11. A method according to any of claims 1 to 8, wherein said resultant fabric comprises an area weight of between 150g/m2 and 500g/m2 .

12. A method according to any of claims 1 to 8, wherein said resultant fabric comprises an area weight of between 200g/m2 and 500g/m2 .

13. A method according to any of claims 1 to 12, wherein said resultant fabric comprises a number of warp yarns per inch between 50 and 100 and a number of weft yarns between 25 and 70.

14. A method according to any of claims 1 to 12, wherein said resultant fabric comprises a number of warp yarns per inch between 70 and 100 and a number of weft yarns between 35 and 60.

15. A method according to any of claims 1 to 14, wherein said resultant fabric comprises a resultant yarn count of the warp yarn between Nm 15 and Nm 55 whilst a resultant yarn count of the weft is between Nm 10 and Nm 40.

16. A method according to any of claims 1 to 14, wherein said resultant fabric comprises a resultant yarn count of the warp yarn between Nm 15 and Nm 30 whilst a resultant yarn count of the weft to be between Nm 15 and Nm 30.

17. A method of forming a fire retardant material without the hitherto necessary step of applying a fire retardant composition to the fabric, yarn or fibres, by forming a fabric from yarns comprising a combination of cotton and wool fibres.

18. A method of forming a fire retardant fabric substantially as hereinbefore described.

19. A method of forming a fire retardant material without the hitherto necessary step of applying a fire retardant composition to the fabric, yarn or fibres substantially as hereinbefore described.

20. A method of making a piece of furniture substantially as hereinbefore described.