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(11) | EP 0 705 550 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | An upholstery set |
(57) An elastic upholstery set, more in particular - but not exclusively - for the upholstery
of chairs, seats and the like as preferably used in public buildings and in vehicles
for public transport, for example, whereby the elastic upholstery set is provided
with a resilient armouring part (2) and a pressure-distributing part (3,4), whereby
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[0001] The invention relates to an elastic upholstery set, more in particular - but not exclusively - for the upholstery of chairs, seats and the like as preferably used in public buildings and in vehicles for public transport, for example, whereby the elastic upholstery set is provided with a resilient armouring part and a pressure-distributing part, whereby
- said joint parts are at least substantially comprised of an armoured pressure-distributing padding, on which a flexible layer is provided, or whereby
- said armouring part is at least substantially comprised of a resilient armouring layer, whilst the pressure-distributing part is at least substantially comprised of a pressure-distributing layer provided thereon.
[0002] Such an elastic upholstery set is known from European patent No. 0 355 879, also in the name of Emsta Breda B.V. The furniture used in public buildings or in vehicles for public transport is often a target for all sorts of vandalism. The resulting damage inflicted with, for instance, a knife is generally so serious that the furniture is no longer suitable for further use. Such acts of vandalism entail a great deal of expense, for example for municipal authorities, since furniture which has thus been damaged and rendered unsuitable for further use needs to be - often even completely - replaced. In one embodiment of the elastic upholstery set disclosed in the aforesaid European patent the pressure-distributing part is comprised of two pressure-distributing layers made of haircloth or natural fibres, the technical term for said fibres being hairlock/cocolock fibres, between which the resilient armouring layer, for example a metal mesh armouring, is sandwiched. In another embodiment the resilient armouring part and the pressure-distributing part form a reinforced padding of a foam material.
[0003] Another elastic upholstery set is known from French patent application No. 2,592,334. The elastic upholstery disclosed therein comprises an anti-wear top layer, a flexible layer of synthetic aramid fibres ("Kevlar"), a resilient armouring in the form of a metal mesh, as well as a waterproof layer, for example made of polyurethane. The flexible layer of synthetic aramid fibres and the metal mesh are intended to be able to withstand the impact of knives wielded by vandals. A drawback of the elastic upholstery set disclosed in French patent application No. 2,592,334 is that in practice a person using the seat will be bothered by the metal mesh, which makes the seat less comfortable in case of prolonged use, whilst the ability of the known elastic upholstery set to withstand the impact of knives in case of vandal action is not completely satisfactory.
[0004] An elastic upholstery set known from Dutch patent application No. 8000287 includes a relatively plastic, flexible and thick upholstery material, which is armoured with a metal mesh so as to be able to withstand the impact of knives in case of vandal action. Said plastic, flexible and thick upholstery material is made of polyvinyl chloride, whilst said mesh consists of a layer of metal spiral springs of the type used in box-spring mattresses. A drawback of this known elastic upholstery set is that in practice it has proved to be insufficiently able to withstand the impact of knives in case of vandal action, since the plastic, flexible and thick upholstery material can still be damaged with a knife, for example in places located between parts of the metal spiral springs. A further drawback of this known elastic upholstery set is that it is not able to resist fire in case of vandal action. Although the polyvinyl chloride layers of the plastic, flexible and thick upholstery material can be made fire-resistant by an additional treatment, such a treatment appears to be costly, whilst in addition to that it does not appear to be entirely effective in practice.
[0005] The object of the invention is to provide a strong and comfortable, elastic upholstery set, which is able to withstand the impact of knives as well as fire, for example in case of vandal action, and which can be manufactured inexpensively, whereby adjacent parts/layers of the elastic upholstery set are attached together in an efficient manner, and whereby an environment-friendly recycling or repair/replacement of these parts/layers can efficiently be achieved.
[0006] To this end an elastic upholstery set of the kind mentioned in the introduction is according to the invention characterized in that at least two adjacent parts/layers of the elastic upholstery set are glued together by means of a thermoplastic glue which looses adhesive power at a temperature lying between 80°C and 120°C, particularly between 85°C and 110°C, preferably 100°C. Thus a very strong and comfortable elastic upholstery set is provided, which not only is able to withstand the impact of for example knives (because of its pressure-distributing properties) as well as fire, but which also forms a compact and strong unit, since adjacent parts/layers of the elastic upholstery set are "fixedly" interconnected. A significant advantage of the "loosening" temperature is that the elastic upholstery set will readily delaminate upon being heated to this temperature, so that parts/layers forming part of the elastic upholstery set can be separated from each other. This makes it possible to separate the recyclable parts/layers of the elastic upholstery set from the nonrecyclable parts/layers, which is an environment-friendly aspect. A further advantage is that a part/layer forming part of the upholstery set according to the invention can (partially) be cleaned, repaired or even replaced independently from the other parts/layers thereof, without the need of replacement of the complete upholstery set. It will be evident that the top (velours) layer of the upholstery set needs regular cleaning and repair.
[0007] In embodiment of an upholstery set according to the invention, the glue has an adhesive power lying between 2 and 6 N/mm, particularly between 3 and 5 N/mm, preferably 4 N/mm, taken between adjacent parts/layers of the upholstery set.
[0008] It is preferred to use a glue which has recall (i.e. "memory") of elasticity, that is, a glue which will return to its initial position after having been loaded by a user of the elastic upholstery set, or after having been (point) loaded by a knife in case of vandal action. This results in a very comfortable elastic upholstery set, whereby adjacent parts/layers of said elastic upholstery set are prevented from moving with respect to each other.
[0009] The glue is preferably of the so-called hot-melt type (i.e. the glue is applied as a liquid, thereby ideally pentrating into the parts/layers of the upholstery set, thus ensuring excellent adhesive properties) and based on polyamide or polyurethane. In another embodiment said glue is preferable a two component glue based on polychloroprene. A glue of this type has appeared to produce very good results in practice. Such a glue in a preferred embodiment exhibits the following properties as regards its two components A and B:
| A | B | |
| Base | polychloroprene | polyisocyanate |
| Colour | beige | dark brown |
| Viscosity at 25°C | approx. 350 mPa.s | approx. 5 mPa.s |
| Density | approx. 840 kg/m³ | approx. 980 kg/m³ |
| Solid matter content | approx. 19% | approx. 30% |
| Flash point | below 0°C | below 0°C |
| Solvents | a mixture of aliphates and esters | esters |
[0010] Another embodiment of an elastic upholstery set according to the invention is characterized in that the pressure-distributing part/the pressure-distributing layer and/or the flexible layer are made of synthetic fibres, preferably aramid fibres. In practice aramid fibres, which are for example marketed under the brand names Twaron and Kevlar, appear to be very well able to withstand the impact of knives (because of their pressure-distributing properties) and fire in case of vandal action.
[0011] The invention furthermore relates to a chair or a seat provided with an elastic upholstery set according to the invention.
[0012] The invention will be explained in more detail below with reference to the Figure shown in the accompanying drawing, which is a perspective view of an elastic upholstery set according to the invention.
[0013] The Figure shows a "stab and flame-resistant" elastic upholstery set according to the invention, comprising an upholstery material (1) of velours of the so-called Delcar-SNCF type, of a resilient armouring part (2) in the form of a metal mesh armouring, which is positioned between two layers (3,4) of aramid fibres. The layers (3,4) not only function to make the unit able to withstand for example fire and the impact of knives, but they also function as pressure-distributing layers, which makes the seat very comfortable, even in case of prolonged use. A foam padding (5) or preferably an aluminium frame construction (5) comprising zigzag springs provides the elastic upholstery set with any additional comfort that is required.
[0014] The weight of the layer (3) of aramid fibres preferably ranges from 240 - 280 g/m², more preferably 260 g/m². The weight of the layer (4) of aramid fibres preferably ranges from 160 - 180 g/m², more preferably 170 g/m². In a preferred embodiment the metal mesh armouring (2) has a wire thickness ranging from 0,5 - 3 mm, preferably 1 mm (with interspaces having a diameter of 5 mm), whilst the mesh armouring (2) is preferably able to withstand a point load of 3 - 5 kg, more preferably 4 kg. The velours upholstery material (1) finally has an adhesive power of more than 2 N/mm, preferably 4 N/mm with respect to the layer (3) of aramid fibres.
[0015] Adjacent layers (1, 2, 3, 4, 5) of the elastic upholstery set are glued together by means of a thermoplastic glue (6) having recall of elasticity. The glue (6) will return to its initial (unloaded) condition after having been loaded by a user of the elastic upholstery set, or after having been (point) loaded by a knife in case of vandal action.
[0016] The glue (6) looses its adhesive power at temperature lying between 80°C and 120°C (preferably at 100°C), so that the upholstery set according to the invention will readily delaminate upon being heated to this temperature. This has the advantage that parts of the upholstery set (the velours material (1) and the other layers (2,3,4,5)) can be separated from each other, and subsequently can be recycled independently of each other. A further advantage is that the above-mentioned separation of parts of the upholstery set makes it possible to (partially) repair or replace a specific part thereof, without the need of replacement of the complete upholstery set. For example, by a suitable heating to the temperature mentioned earlier, the layer of upholstery material (1) can be separated from the rest of the upholstery set, after which (partial) cleaning, repair or even replacement of the material (1) can take place. After having been cleaned or repaired, for example, the material (1) can then be glued in place to the rest of the upholstery set, so that a "new" complete upholstery set at low costs is achieved ready for use. The above-mentioned temparature range has been found after extensive experiments, in view of the different behaviour of physical and chemical properties of parts of the upholstery set when heated.
1. An elastic upholstery set, more in particular - but not exclusively - for the upholstery
of chairs, seats and the like as preferably used in public buildings and in vehicles
for public transport, for example, whereby the elastic upholstery set is provided
with a resilient armouring part and a pressure-distributing part, whereby
- said joint parts are at least substantially comprised of an armoured pressure-distributing padding, on which a flexible layer is provided, or whereby
- said armouring part is at least substantially comprised of a resilient armouring layer, whilst the pressure-distributing part is at least substantially comprised of a pressure-distributing layer provided thereon,
characterized in that at least two adjacent parts/layers of said elastic upholstery set are glued together by means of a thermoplastic glue which looses adhesive power at a temperature lying between 80°C and 120°C, particularly between 85°C and 110°C, preferably 100°C.2. An elastic upholstery set according to claim 1, characterized in that the glue has an adhesive power lying between 2 and 6 N/mm, particularly between 3
and 5 N/mm, preferably 4 N/mm.
3. An elastic upholstery set according to claim 1 or 2, characterized in that the pressure-distributing part/the pressure-distributing layer and/or the flexible
layer are made of synthetic fibres, preferably aramid fibres.
4. An elastic upholstery set according to claim 1, 2 or 3, characterized in that said glue has recall of elasticity.
5. An elastic upholstery set according to any one of the preceeding claims 1 through
4, characterized in that said glue is based on polyamide or polyurethane.
6. An elastic upholstery set according to any one of the preceding claims 1 through 4,
characterized in that said glue is a two component glue based on polychloroprene.
7. An elastic upholstery set according to claim 6, characterized in that said glue exhibits the following properties as regards its two components A and B:
| A | B | |
| Base | polychloroprene | polyisocyanate |
| Colour | beige | dark brown |
| Viscosity at 25°C | approx. 350 mPa.s | approx. 5mPa.s |
| Density | approx. 840 kg/m³ | approx. 980 kg/m³ |
| Solid matter content | approx. 19% | approx. 30% |
| Flash point | below 0°C | below 0°C |
| Solvents | a mixture of aliphates and esters | esters |
8. A chair or a seat provided with an elastic upholstery set according to any one of
the preceding claims 1 through 7.