This invention relates to bandages. BACKGROUND ART Compression bandages are used to facilitate healing. For example, a compression bandage wound around a patient's leg to give a pressure gradient up the leg can facilitate the healing of venous ulcers.

Knitted and woven stretchable fabrics are used for this purpose.

However, with known fabrics the pressure applied in use can cause discomfort to the patient at pressure points, e.g. around bony prominences, and may give rise to chafing or injury. To avoid this it may be necessary to introduce padding beneath the bandage.

Softer bandage fabrics are known such as non-woven or felted fabrics, but these do not have sufficient strength in themselves to permit application of satisfactory levels of compression. They are commonly used for comfort as padding beneath plaster casts and compression bandages. DISCLOSURE OF THE INVENTION

An object of the present invention is to provide a bandage with which adequate compression can be achieved with a soft, comfortable structure. According to the invention therefore there is provided a compression bandage which is characterised by the use of a spacer fabric having opposite face structures united and held in spaced disposition by threads.

By using a spacer fabric it is possible to attain high levels of compression with a soft, comfortable padding structure.

Most preferably the fabric is formed by a knitting operation, particularly warp knitting, in so far as this is a convenient way of attaining required strength and stretchability.

Spacer fabrics can be formed with double needle bar plush machines. It is already known to form such fabrics but hitherto the fabric has been separated between the face structures by severing the spacer threads to give two plush-faced fabrics, or the spacer fabric has been used without separation as a structural or insulating lining or cover. The present invention is based on the realisation that spacer fabrics can be used to advantage in the field of compression bandages.

Any suitable materials or combination of materials may be used for the spacer fabric.

Preferably the outer face structure i.e. that which in use faces away from the patient's skin, is formed from multifilament yarns such as nylon or polyester alone or in combination with durable, elastic yarns, particularly multifilaments or monofilaments for example of polyurethane fibres such as

Elastane or that sold under the registered trade mark Lycra.

Preferably the inner face structure, i.e. that which faces or is in contact with the patient's skin in use, is formed from a suitably comfortable, or skin compatible material, particularly cotton and/or viscose yarns alone or in combination with elastic yarns.

It is also possible to have cotton or other absorbent yarns away from the patient's skin so as to encourage flow of moisture away from the body surface.

The spacing threads are preferably relatively strong, self-supporting threads, which, suitably may be monofilaments or multifilaments of a polyester or nylon or other suitable materials, such as Coolmax which is a four channel Dacron polyester fibre with a special cross-section structure, selected to give the desired capillary action and resilience or padding effect.

Preferably also, the threads run between the face structures in two or more sets respectively at two or more opposite inclinations, thereby to provide

resistance to lateral displacement i.e. to displacement of the face structures in opposite directions parallel to such structures. The fabric may have markers provided thereon to assist in application of predetermined levels of compression. The markers which are preferably geometric may be arranged so that they distort visually on stretching whereby the required level of compression is attained when the distortion is of a predetermined nature. For example, the marks may comprise printed rectangles which are stretched to become squares, or ovals which become circles, or other shapes.

There may be two or more sets of markers corresponding to two or more levels of compression.

The bandage of the invention may have any suitable degree and configuration of elasticity. Most preferably it has a elongation in the range

30% to 120% in a longitudinal direction of the bandage. It is however also possible to have elasticity in the transverse direction, and also the elongation may be outside the above range perhaps as low as 10% or as high as 200%.

SUBSTITUTE SHEET (fiULE 26)

The padding characteristics of the bandage will depend on the spacing between the face structures and the characteristics of the spacer threads. Spacings in the range 1 .5mm to 60mm are possible depending on requirements, (a preferred range being 2.0 to 5.00mm), and the spacer threads may have a linear density of 8 to 300 decitex, particularly 10 to 100 decitex and preferably 1 5-85 decitex. Multifilament or monofilament synthetic yarns used in the face structures may have linear densities in the range 22-330 decitex. Where used cotton yarn may be single or folded having a count Ne 1 /30 to 1 /60 or 2/60 to 2/1 20. The spacer fabric may be finished in the usual way with a stentor and application of heat/steam to give desired properties, and, if desired the fabric may be surface finished e.g. by brushing.

The fabric may be cut to give bandage lengths of say 3 ¹ / ₂ to 4 metres and a suitable width of say 5cm-15cm (particularly 7.5cm, 10cm or 12cm). The invention also provides a method of forming a compression binding in situ wherein a bandage as described above is wrapped around an area of a patients body and maintained in position in compression thereon. The compression may be in the range 10-50mm Hg.

The bandage may be used alone or with other materials or fabrics. Thus, in some cases it may be desirable to introduce padding separate to the bandage, and/or to apply additionally conventional compression and/or crepe bandages. BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described further by way of example only

and with reference to the accompanying drawings in which:

Fig. 1 is a diagrammatic perspective view of part of the knitting pattern of a spacer fabric; Fig. 2 is a diagrammatic perspective view of a sample of the fabric-

Fig. 3 is a plan view of a length of bandage in accordance with

one embodiment of the invention made from the spacer

fabric; and Fig. 4 is a diagrammatic view of part of a knitting machine used to make the spacer fabric.

DESCRIPTION OF PREFERRED EMBODIMENT

A compression bandage 1 , as illustrated in the drawings, is supplied

as a rolled strip say 10cm wide, 3.5m long, and approximately 3mm thick.

The bandage 1 is formed from a warp knitted spacer fabric having an outer face structure 2, an inner face structure 3, and link threads 4 between these structures 2, 3. More specifically, the inner and outer face structures

2, 3 are both warp knitted textile structures united by the inserted spacer threads 4 generally in the manner of formation of a double plush structure.

Fig. 4 shows part of a warp knitting machine used to make the fabric. Two sets of needles 5,6 are used to form the two face structures 2, 3

(Fig. 2) and six yarns 7-12 are fed via guide bars L1 -L6 to the needles 5, 6.

Two of the yarns 7, 8 or 1 1 , 1 2 form pillar stitches and linking face stitches at each face structure 2, 3, and two yarns 9, 10 are interconnected between the face structures 2, 3 to form criss-crossed spacer threads 4. Trick plates

1 3, 1 4 associated with the needle sets 5, 6 are maintained at a predetermined spacing to determine the spacing between the face structures 2, 3.

The outer face structure 2 is formed from nylon multifilaments (as the pillar stitches) and elastic multifilaments or monofilaments e.g. Lycra

(registered trade mark) (for the linking face stitches).

The inner face structure 3 is formed from cotton yarns (as the pillar stitches), and elastic multifilaments e.g. Lycra (for the linking face stitches) .

The spacer threads 4 are polyester or nylon monofilaments. Fig. 1 shows spacer threads 4 which are all parallel to each other for the sake of clarity. There are two sets of spacer threads 4, one set as shown and the other set crossing these with the same inclination in the opposite direction.

The spacer threads 4 act to hold the face structures 2, 3 apart in relatively fixed relationship with regard to directions parallel and perpendicular to the faces. Compression of the fabric is resisted by the threads whereby the fabric has the nature of a resiliently compressible padding material.

The bandage 1 is also stretchable longitudinally as a consequence of the knit structure, particularly the stitches, and the elastic yarns used. The spacer fabric is finished with a stentor to give desired elongation which would typically be in the range 30% to 120% in the longitudinal direction.

The fabric is cut to give a bandage of the desired length and width. With the spacer fabric structure, the fabric can be cut without run-back.

The following table gives five example structures, all made on a double needle bar plush machine:

Example 1 2 3 4 5 gauge (needles per inch) 22 22 22 22 22 number of guide bars 6 6 6 6 6

Trick plate spacing 3 2.5 3 3 2

Fabric weight (g/m ² )

grey 370 450 450 515 650 finished 430 417 504 470 690 Guide bar Yarns L1 A A A A A L2 B B B B B L3

L4 C C C C C

L5 B B B B B

L6 D D D D D

Stitch density grey 160 180 1 55 200 120 finished 170 160 1 52 170

Yarns A-C are as follows (the first number being linear density in decitex, and the number following the letter 'f is the number of filaments).

Example A B C

1 78f 18 Nylon 78f1 Elastane 33f1 Polyester

2 78f 1 8 Nylon 78f1 Elastane 33f1 Polyester

3 1 67f48 Polyester 44f1 Elastane 30f1 Polyester

4 44f34 Nylon 78fl Elastane 33f1 Polyester

5 76f24 Polyester 156f1 Elastane 55f34 Coolmax Yarn D is single or folded cotton yarn having a count Ne 1/30 to 1/60 or 2/60 to 2/1 20.

Yarn A may have a linear density in the range 22-330 decitex and C in the range 8-300 decitex.

As shown in Fig. 3, rectangles 1 5 are printed at regularly spaced intervals along the top face of the bandage. In use, by way of example, the bandage 1 can be wrapped tightly around a patient's leg with the inner face structure 3 of cotton yarns in contact with, or facing, the patient's leg. The bandage 1 is stretched longitudinally so that compression is applied. The printed rectangles 15 are used as a guide to assist in attaining a desired level of compression. That is, the bandage 1 is stretched longitudinally until the rectangles 1 5 become squares.

The bandage 1 is then secured in position in the usual way thereby to define a therapeutic compression binding on the patients leg. A compression gradient can be attained and maintained along the leg as desired. The spacer fabric has a padding effect whereby the compression is applied and maintained without causing undue discomfort or damage. Compression and padding are achieved with the same bandage fabric whereby it is not necessary to use additional padding material, although of course this may be used if desired, as also may other compression or crepe

bandages.

It is of course to be understood that the invention is not intended to be restricted to the details which are described above by way of example only. In particular the materials and parameters of the spacer fabric can be varied as desired and in order to achieve desired levels of compression and padding.

If minimal padding is required e.g. with a fabric thickness of say 1 .5

to 2.5mm, it is possible to use a warp knit structure, as shown in Fig. 1 , with the monofilament spacer threads 4 running in one direction only. Especially with crossed threads as described above much larger spacing is possible giving thicknesses in the range 3-12mm, larger spacings up to 30mm or even 60mm are in fact attainable.

The textile face structures 2, 3, may be knitted with any suitable open-structured, honeycombed, closed or patterned arrangement or combination thereof.

The padding resilience of the fabric, i.e. the force required to press the two fabrics together, is dependent on the mass of monofilaments between the face structures 2, 3, which is determined by the yarn count, stitch density and machine gauge in relation to the spacing distance, and these parameters will be appropriately selected to meet requirements.

SUBSTITUTE SHEtT (RULE 26)