Mattress and upholstery covers

INTRODUCTION

This invention relates to permanently fixed or removable stretchable covers for mattresses, cushions and similar upholstery items, such covers including amongst other things mattress covers, fitted sheets and cushion covers. For brevity, the following description refers mainly to mattresses and mattress covers, but the invention is of more general applicability.

BACKGROUND

Mattress covers comprise upper and lower panels, joined by side panels; or an upper panel and skirt, without a lower panel. The covers may be fixed about or removable from a mattress or mattress core. Examples of mattress cover panel materials are woven materials (which often have little elasticity), coated materials (e.g. for incontinence, where the coating or backing can decrease the elasticity of the top material) and quilted materials (where even if the encapsulating fabric is stretchable, the filling and stitching makes the quilted construction relatively inelastic). Examples of mattresses and mattress cores are waterbeds, airbeds, foam cores and pocket inner sprung cores.

Fitted sheets are similar, in that they comprise a top panel and a (usually elasticated) skirt for securing the top panel in place over a mattress. The fitted sheet forms the outermost item of bed linen fitted to the mattress when the bed is "made", and is intended to be frequently changed and laundered; whereas a mattress cover is usually fitted directly to a mattress or mattress core and is required to be changed less frequently or is permanently attached to the mattress. Other bedding items tailored to fit around a mattress may be used, and all such items are referred to hereafter as "mattress covers", unless the context demands otherwise.

A known problem with covers for mattresses and other upholstery items is in making them able to move or stretch when used (e.g. when a person is lying or sitting on them), to permit of increased comfort, and to return to a taut, wrinkle free condition when not being used.

It is known to produce mattress covers entirely from stretchable fabric; see for example GB-A-1 193 872 (VONO Ltd.). The problem with this type of mattress cover is that the top panels tend to wrinkle or ruck in use. If such materials are quilted, elasticity is decreased.

It is also known to produce mattress covers with inelastic top and bottom panels and stretchable skirts; see for example US-A-6 199 231 (ZAFIROGLU), US-A-5 603 132 (ZAFIROGLU), US-A-5 636 393 (ZAFIROGLU et al), EP-A-0 409 585 (PERFECT FIT IND. INC), as well as the Vono Ltd. patent specification referred to above. The problem with this type of mattress cover is that the skirts cannot effectively tension upper and lower panels, because tension forces and movement of the cover have to transfer around upper and lower edges of the mattress or other structure to which the cover is fitted. Friction at these edges reduces the ability of the skirt to tension the upper and lower panels.

It has also been proposed to provide mattress covers with memory fabric top and bottom panels, see US-A-4 757 564 which discloses a mattress cover enveloping a resilient member of a mattress, the cover including a top panel having a memory fabric with particular stretch characteristics for expanding to a different size and shape when a person is lying on the mattress, and particular retention characteristics for returning to the original size and shape when the person is removed from the mattress. The memory fabric is stated to be especially desirable in avoiding the "hammock effect" in hybrid water mattress constructions. The problem with this cover is that panel fabric is limited to a particular, memory effect material, such that conventional quilting of cover fabrics cannot be obtained [see column 4 lines 15-37].

OBJECT OF THE PRESENT INVENTION

It is an object of the present invention to provide a cover for an upholstery item such as a mattress or cushion that provides a stretchable or tensionable panel (e.g. a top panel or top and bottom panels) that can use conventional panel materials.

STATEMENT OF INVENTION

According to the present invention, a cover for a mattress, cushion or similar upholstery item includes a cover panel comprising interconnected areas of relatively inelastic and elastic materials; the cover further comprising a skirt, characterised in that the skirt has a higher elastic modulus, either in the direction normal to the cover panel periphery, or in all directions, relative to the elastic areas. By this means, conventional panel fabrics can be combined with elastic material such that the feel of the cover can be maintained whilst the panel can deflect in use to enhance comfort and can be kept taut and wrinkle-free when unused.

According to an embodiment of the present invention, a top or bottom panel of the cover comprises a central area of relatively inelastic material and a peripheral area of relatively elastic material. By this means, the central area can exhibit the conventional panel characteristics; whilst the surrounding elastic peripheral area permits the central area to relatively uniformly deflect in use and keeps the central area taut and wrinkle-free.

In some embodiments, all or part of the elastic areas may be more elastically stretchable in all directions than the areas of inelastic material. Additionally or alternatively, all or part of the elastic areas may be more stretchable in one direction than in another. For example, the elastic areas may have a lower elastic modulus in directions transverse to the periphery of the cover panel in which they are situated, than in directions parallel to the periphery. This enables the cover to be tailored more specifically to the requirements of a particular mattress, bed, cushion or other upholstery item configuration and mechanical properties.

The skirt provides an "anchorage" against which the elastic and the interconnected relatively inelastic areas of the cover panel may be maintained in tension.

Further preferred features and embodiments are set forth in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWING

An embodiment of the invention is illustrated, by way of example, in Fig. 1, which is a perspective view of a mattress cover.

SPECIFIC DESCRIPTION

Fig. 1 shows a mattress cover 10 positioned about a conventional mattress core and comprising an upper panel 12, a lower panel 14. A skirt 16 is joined to the peripheries of the upper and lower panels by rolled edges 18. In this embodiment, the lower panel 14 is attached to the skirt 18 by a sliding clasp fastener 20, proximate the lower rolled edge 18. This fastener enables the cover to be removed from the mattress in known manner for cleaning, or substitution with another cover having different properties, etc.

The top panel 12 is shown to comprise a central rectilinear area 22 of conventional, quilted, essentially inelastic material such as double Jersey, quilted with textile fibres e.g. polyester or wool wadding material and / or foam e.g. PU, PE and / or Latex, and a backing material such as 100% cotton tricot. However, the invention allows a wide variety of different fabrics and fabric constructions to be used in the central area, for a taut and wrinkle-free panel of neat appearance and comfortable feel. Any suitable textile material or materials, such as woven, non-woven or knitted fabrics of polyester, cotton, silk, viscose or mixed fibres, or CLIMACONTROL™ or TENCEL™ top fabrics, can be used. Additionally or alternatively, the central area may comprise a breathable or non-breathable, fluid repelling and / or resistant material e.g. Terry cloth: 80% cotton, 20% polyester, PU laminated, for use by babies, elderly or incontinent people e.g. in bed mattresses for nursing homes, residential care homes, and children's mattresses. The fluid repelling / resistant material may be used alone or positioned below a quilted or moisture absorbent top layer.

Central area 22 is surrounded by a peripheral area or band 24 of elastic material; such a knitted elastic ticking made of 33% polyamide fibre (Tactel® Micro Touch 6,6 nylon), 44% elastane fibre (Lycra® clear) and 23% cotton fibre. The fabric weight is approximately 240 g/m² (+/- 8%) and has a nominal longitudinal stretch of 105 - 135% (120 + / - 15%) and a nominal lateral stretch of 110 - 130% (120 + / - 10%). Suitable material can be obtained from numerous commercial sources, see e.g. www.boos-textil.de.

The elastic peripheral area 24 applies a substantially consistent tension to the central area 22. The relative width of the elastic periphery, the elastic modulus and elasticity of the material from which it is formed, e.g. 50 or 100% nominal maximum elongation, and the amount of pre-stretch generated in the cover panel when applied to an unoccupied mattress enables the degree of elasticity and pre-tensioning of the top panel to be adjusted to the desire of the mattress manufacturer, given the mattress core characteristics and/or the type of bed; e.g. waterbeds, airbeds, foam cores, pocket interior sprung cores. Similar considerations apply for other upholstery items such as cushions for furniture, wheelchairs and automobiles.

The lower panel 14 may similarly be provided with an elastic area, the same as or different from the upper panel 12. This both helps to maintain a taut fit of the whole cover 10 about a mattress and, for reversible mattresses or by removing and turning the cover, permits of alternative panel characteristics.

The skirt 16 is also of conventional quilted, essentially inelastic material. An inelastic skirt provides a substantially fixed anchorage (neglecting or absent any compression of the mattress or other structure within the cover) against which the area of elastic material can be maintained in tension, in turn maintaining the interconnected inelastic panel area in tension. It is preferred that all or part of the skirt is made from relatively inelastic material, so that the area of elastic material does not extend around an edge of the mattress or other upholstery item, and so the stretching and elastic recovery of the elastic material is not significantly impeded by friction.

Mattress or other covers may be provided with alternative patterns of inelastic and elastic areas, according to particular characteristics of mattress, bed or other upholstery item. For example, adjustable beds, wherein one mattress part can be adjusted independently of another part may have elastic areas acting on separate inelastic areas and the same or additional elastic areas permitting one mattress part to move independently of the other mattress part whilst retaining a single, overall taut and conforming mattress cover for that mattress. Although the foregoing description mainly concerns generally rectangular mattresses, the invention may be applied to covers for upholstery items of other shapes, e.g. for cushions and mattresses that are circular, oval, octagonal, etc. in plan.

In summary, covers in accordance with the present invention avoid or reduce wrinkles, allow use of a wider range of materials, improve user comfort and provide an improved appearance in comparison with conventional covers.