Note: Descriptions are shown in the official language in which they were submitted.
t
WO 95/08935 2 1 6 9 4 6 1 PCT/AU94/00597
VANDAL RESISTANT MATERIAL
The present invention relates to a vandal resistant materials, in particular
vandal resistant materials for use in covering seats used in public places or
public or other transport vehicles, and to methods of manufacture of such
5 materials. The invention also relates to methods of manufacture of vandal
resistant seats from the materials of the invention.
Attempts have been made to overcome the problem of damage caused to
seats used in public places and in public or other transport seating by slashing,
cutting or otherwise tearing of seating with knives, razors or other implements,10 sharp or otherwise. To date these attempts have concentrated on the vandal
resistance of the various products and have not been concerned with providing
an acceptable comfort level in the end product for the user or occupier of the
seat. Furthermore, in recent times seats and cushions used in public places or
public or other transport vehicles, are typically being formed with contours in
15 order to provide additional support and comfort to the occupier. It is therefore
necessary for the vandal resistant material to conform to the many contours of
the seat or cushion to which it is to be applied.
Known vandal resistant materials have been unable to provide a vandal
resistant covering which is easy to fit to a wide variety of seats such as bus, train
20 or tram seats by known upholstery techniques.
Danton, for example, in GB Patent No. 2,041,472 (and US Patent No.
4,423,102), discloses a furniture covering utilising an outer covering formed of a
relatively thick, pliable plastics material, and which is reinforced through the use
of a network of tear resistant fibres such as for example, metallic fibres. Danton
25 provides for an upholstery covering for a seat including an outer flexible cover
Iayer of solid plastics material and a network of metallic spiral coil springs
attached to the outer layer by an intermediate connection layer of foamed
plastics material on the underside of the cover layer, in which the turns of thesprings are only partly embedded in the intermediate layer of foamed plastics
30 material.
Danton, in US Patent No. 5,165,556 utilises the above material and
moulds the material into a rigid moulded seat frame. The user comfort of this
WO 95/08935 -^ ~ 2 1 6 9 4 6 1 PCT/AU94/00597--
seat is reduced by having rigid moulded edges around the seat cushion.
Park et. al., in US Patent No. 4,828,908 disclose a vandal resistant
seating material in which a layer of flexible metal or non-metal matrix material is
embedded within a compressed plastics foam material, produced by introducing
5 a plastics material in a mould containing a metal or non-metal matrix, allowing
the plastics material to foam and then compressing the combination to
suhst~ntially remove all gas produced during the foaming step.
Clements, in AU Patent No. 639,972 (PCT/AU90/00585) discloses a
method of manufacturing a vandal resistant seat material which includes
10 placing a wire mesh in a mould, closing the mould to form a cavity with a
predetermined volume, injecting a foamable plastics material into the cavity in
which the volume of the unfoamed foamable plastics material is at least 50% of
the volume of the mould cavity and in which the volume of the mould cavity is upto 50% of the volume of the fully expanded foam (that is, the volume of the foam15 if it were permitted to foam and expand unfettered to maximum foamed volume).Enlow et. al. in US Patent 3,647,608, discloses vandal resistant articles
that comprise or contain a low density foam structure characterised by having a
cut resistant surface including a layer of metal wires, selected from the group
consisting of unconnected, randomly oriented, flexible metal fibres and wire
20 mail ("wire mail" being a mesh of wires or a flexible mesh of small metal rings or
squares), embedded in the foam immediately beneath the surface of the foam.
The foam material on it's cut resistant surface, may be covered with a thin layer
of a wear-resistant material adhered thereto. Enlow discloses that a wide range
of rigid, semi-rigid, or flexible, organic or silicone plastic foams, having a density
25 of from 1 to 50 Ib ft-3 (i.e. about 16 to 800 Kg m-3) may be used to produce a
large variety and diversity of products including:- Automobile seats, bus seats,theatre seats, wall padding, furniture, automobile dashboards, tractor seats,
stadium seats, sport and recreation cushions, sofa cushions, reinforcing,
supporting and rigidifying structures, wheels, sun visors, instruments, decorative
30 buttons and knobs. It is particularly to or in the foam structure portion of these
articles that Enlow desires to place or form a cut-resistant surface. The foam
density range indicates a foam material which is expanded, from it's original
A r ~ ~ -
~ W095/08935 2 1 6 9 ~ 6 l PCT/AU94/00597
unexpanded volume with a density of about 63.5 Ib ft-3, by a factor of from 1.3 to
65. The depth to which the metal fibres are embedded is from 0.030 to 0.200 in.
(i.e. about 0.75 to 5.0 mm.). Depths of less than 0.030 in. (0.75 mm.) permit the
layer of wires to "strike through" the surface of the foam. The thickness of the5 layer of metal wires is from 0.05 to 5.0 mm and the thickness of the wear
resistant material is from 0.030 to 0.200 in. (i.e. about 0.75 to 5.0 mm.).
Ward, in Australian Patent No. 594037 discloses a laminated article
which may be used as a covering for a seat to provide increased resistance to
- puncture or slashing. The article includes a moulded non-cellular thermosetting
10 polymeric support member and a reinforcing wire mesh fully embedded within
the moulded support member. However the material disclosed by Ward is
focussed on improving the vandal resistance of seats and does not address the
problem of providing an acceptable level of comfort in the covered seat or
cushion. Vandal resistant materials made in accordance with Ward have been
15 found to possess a rigidity and inflexibility which is higher than desirable in
order to provide desired levels of comfort in the covered seat or cushion. It has
also been found that it is difficult to apply vandal resistant materials made inaccordance with Ward to seats and cushions, particularly to contoured seats
and cushions, by known upholstering techniques.
Drouin, in EP 0190064 discloses a covering for seats, in particular seats
used in public places or public transport vehicles, for providing protection
against vandalism. Drouin discloses a vandal resistant covering for seats, the
covering being of a composite nature including at least three separate
superimposed layers. The first layer is a decorative layer of thin material; the25 intermediate layer is a vandal resistant layer; and the third layer is of a flexible,
thin material which is preferably fire proof. The material thus includes at least
three distinct layers which are then bonded together by means of a flexible
adhesive. One disadvantage with this material is the need to assemble the
respective layers of the material and then adhere the layers to form a length of30 covering. Such manufacturing steps are less than desirable for mass
production.
r~ U ~ J ) Y
; R~C~IVEO ~ 3 JUL 199.
2t69461
The present invention therefore seeks to provide a relatively thin, flexible,
vandal resistant material which is drapeable (i.e. able to be Udraped'') and which
overcomes or alleviates a number of problems existing in known vandal
resistant materials and which provides a higher degree of user comfort and is
5 readily able to be applied to seats by known upholstering techniques.
To this end the present invention provides a flexible, drapeable vandal
resistant material including a flexible high density synthetic plastics, organic or
silicone, elastomer or foam material, said vandal resistant material having a
length and a predetermined width and having embedded therein a non-woven,
10 knitted or crocheted, metal or synthetic plastics reinforcing material extending
along and across the full length and width of the material, said vandal resistant
material being relatively thin and flexible and drapeable in both the lengthwiseand widthwise directions of the material.
The present invention also provides a method of manufacturing a
15 relatively thin, flexible, vandal resistant material which is able to be draped, and
is able to be applied to a seat or cushion by known upholstering techniques.
To this end the present invention provides a method of manufacturing a
vandal resistant material including a flexible, high density synthetic plastics,organic or silicone, elastomer or foam material having embedded therein a non-
20 woven, knitted or crocheted, metal or synthetic plastics reinforcing material, saidvandal resistant material having a length and a predetermined width and inwhich the reinforcing material extends along and across the full length and
width of the vandal resistant material, said vandal resistant material being
relatively thin and flexible and/or drapeable in both the lengthwise and
25 widthwise directions of the material, in which the said method is characterised
by placing the reinforcing material in a mould, introducing the synthetic plastics,
organic or silicone, elastomer or foam mixture into the mould, closing the mouldso as to force the mixture to flow into and through the reinforcing material andallowing the resultant material to cure to form the drapeable vandal resistant
30 material.
In another form the present invention provides a method of manufacturing
a vandal resistant material including a flexible, high density synthetic plastics,
AMENDED SHEET
IPEA~AU
WO 95/08935 2 1 6 ~ 4 6 1 PCT/AU94/00597
organic or silicone, etastomer or foam having fully embedded therein a non-
woven, knitted or crocheted, metal or synthetic plastics reinforcing material, said
- vandal resistant material having a length and a predetermined width and in
which the reinforcing material extends along and across the full length and
5 width of the vandal resistant material, and in which the thickness of the vandal
resistant material is no more than 5 mm, said vandal resistant material being
flexible and/or drapeable in both the lengthwise and widthwise directions of thematerial, in which the method is characterised by placing the reinforcing
material in a mould, introducing an elastomer or foam mixture into the mould,
10 closing the mould so as to force the elastomer or foam mixture to flow into and
through the reinforcing material and to form a mould cavity of no more than 5
mm thickness, and allowing the elastomer or foam material to cure to form the
vandal resistant material.
The vandal resistant material according to the present invention will be
15 better understood and appreciated from the following discussion of the
preferred features of the material.
Preferably the reinforcing material of the vandal resistant material is
moulded into the elastomer or foam material so as to be fully embedded in the
material.
It is also preferable that the thickness of the vandal resistant material
measures up to 5mm from the thickness of the reinforcing material. Preferably
the thickness of the elastomer or foam material is from 1 to 3.5 mm, with about 3
mm most preferred. Preferably the thickness of the reinforcing material is from
0.5 to 2 mm and most suitably about 1 mm.
Preferably, in the case of a foam material, the foam is expanded to a
volume of no more than 1.3 times the original unfoamed volume and preferably
the density of flexible synthetic plastics organic or silicone foam after foaming is
from 720 to 1120 Kg m-3, more preferably about 800 Kg m-3.
The reinforcing material may be a non-woven crocheted metal reinforcing
30 wire, known as omega wire, with a thickness of between 0.5 to 2 mm. Omega
wire is typically produced by a knitting or crocheting process in tubular form. The
wire may be used directly in a "double thickness" tubular form or alternatively
WO 95/08935 2 1 6 ~ 4 6 1 PCT/AU94/00597--
may be cut and used in a single thickness. The reinforcing material is in the form
of inter-engaging loops in the form of the greek letter "omega" with a preferredrepeat loop unit being 0.6 by 0.6 mm.
Alternatively the reinforcing material may be in the form of a knitted or
5 crocheted synthetic plastics material.
The reinforcing material, be it metal or synthetic plastics material, may be
of monofilament construction or may be knitted or crocheted from a number of
monofilaments. The diameter of the monofilaments in the reinforcing material is
not critical and may be about 0.275 mm. The particular composition of the
10 monofilament, be it metal or synthetic plastics material, is not of particular
importance. Polypropylene and stainless steel wire have both been found to
produce acceptable vandal resistant materials.
The reinforcing materials should not significantly effect the flexibility of thefinal vandal resistant material as compared to an non-reinforced material made
15 from the same foam formulation, although it will be apparent that the inclusion of
the reinforcing material must have some effect in reducing the flexibility of the
material.
In a particularly preferred form of the invention, the vandal resistant
material is moulded in a substantially flat sheet no more than 5 mm thick over
20 the majority of the area of the material, with the material including a tapered or
stepped portion at or near or towards one or more of edges of the material, the
thickness of the vandal resistant material in the tapered or s~epped portion
being as low as the thickness of the reinforcing material.
The vandal resistant material of the invention may also be moulded in a
25 mould to produce shapes conforming to the final desired shape of a seat or seat
cushion to which the vandal resistant material is to be applied, such that when
covered by the vandal resistant material all the exposed faces of the seat or seat
cushion are covered by the reinforcing material of the vandal resistant materialso as to provide vandal resistance. Those exposed areas of the vandal resistant
30 material, other than the area of the direct contact face of the seat, may be formed
having a thickness which is less than the thickness of the direct contact face.
This variation of the thickness of the material is possible whether the material is
~ W O 95/08935 2 1 6 9 4 6 1 PCT/A U94/00597
moulded flat or in a particularly desired shape. The direct contact face may be
moulded having a thickness of, as indicated above, up to 5 mm, whereas the
other eventual exposed faces of the seat material may be moulded having a
thickness of as little as the thickness of the reinforcing material. The change in
5 thickness may be accomplished by a distinct step formed during moulding or by
tapering the material from a particular point from the maximum thickness to the
thickness of the reinforcing material. The change in the thickness of the vandalresistant material may be effected by the inclusion of a masking plate placed inthe mould on top of the reinforcing material which controls the thickness of the10 material in one area to, say, 5 mm and to the thickness of the reinforcing
material, eg. 1 mm in other areas. In the case of a vandal resistant material
moulded to a particular configuration, the dimensions of the parts of the mould
are such that, for example, the direct contact face of the material may be from 3
to 5 mm in thickness whereas the other exposed or "side" faces of the material
15 may be, for example, from 1 to 1.5 mm in thickness.
Preferably the vandal resistant material includes an outer covering of a
protective, decorative or wear resistant woven or non-woven fabric or synthetic
plastics sheet material integrally moulded to the flexible foam with the inner
surface of the outer covering against the reinforcing material and the outer
20 surface against the mould surface. It is also possible to glue the outer covering
to the vandal resistant material. It is also possible, in the case of a woven
woollen outer covering, to glue a thin flexible compatible sheet material or to
apply a thin layer of a compatible plastics or other barrier material between the
outer covering and the reinforcing material if the foam material is likely to "strike
25 through the weave of the woollen material. Preferably the thickness of the
material is from 2 to 3.5 mm.
To highlight the improved flexibility and drapeability of the vandal
resistant material according to the present invention, tests were conducted in
accorciance with Australian Standard AS 2001.2.9, with the details of the
30 Australian Standard being incorporated herein by reference. Australian
Standard AS 2001.2.9 provides a standard method for determining the stiffness
of cloth materials. The Standard describes the procedure for determining the
21 69461
WO 95/08935 PCT/AU94/OOS97
bending length of a cloth by means of a fixed-angle flexometer and for
calculating the flexural rigidity and bending modulus of the sample based upon
the bending length of the sample. Flexural rigidity is a measure of the resistance
of a material to bending by external forces, such that where a material with a
5 high flexural rigidity is stiff whilst a material with a low flexural rigidity is easily
flexed.
Tests in accordance with AS 2001.2.9 were conducted on eight different
materials in total. Tests were conducted on both longitudinal (lengthwise) and
transverse (widthwise) samples of each material. The term longitudinal
10 indicates that the sample was taken along the principal or lengthwise axis of the
material, whilst the term transverse means that the sample was taken in a
perpendicular (widthwise) direction to that of the longitudinal sample.
A non-reinforced woollen fabric, referred to as Sample 1, was tested to
provide an indication of the comparative flexibility of the vandal resistant
15 material made in accordance with the present invention.
Four versions of vandal resistant material made in accordance with the
present invention were tested, these being referred to as Samples 2, 3, 4 & 5.
Three prior art vandal resistant materials, referred to as Samples 6, 7 & 8,
were also tested to highlight the improved flexibility and drapeability of the
20 vandal resistant material according to the present invention when compared to the prior art materia!s.
Details of each of the materials tested are given below. In the
descriptions of the test samples given below, the term "base material" refers tothe material into which the reinforcing material is set (for example an elastomer,
25 rubber or foam), whilst the term "reinforcing material" indicates the reinforcing
material used.
The details of the samples tested were as follows:
SAM PLE NO.
Woven woollen fabric only, 100 % wool, supplied by Norwellan Mills, Stawell,
30 Victoria, Australia. No reinforcing material.
WO 95/08935 2 ~ 6 9 4 6 ~ PCT/AU94/00~97
SAMPLE NO. 2
Base Material: Polyurethane formulation no. EVA-93, Hardness 50, Shore A
Constituent Part by Weight Supplier
Polyol 4701 (polymer polyol) 50 Dow Chemicals Ltd.
5 Polyol HS 100 (polymer polyol) 50 Union Carbide Chemicals
Suprasec VM 25 (isocyanate) 10 ICI Polyurethane Group
Thorcat 535 (phenyl mercury ester) 1 Thor Chemicals (UK) Ltd.
Alumina Hydrated 50 AlcoaAustralia Pty. Ltd.
Reinforcing Material: Polypropylene knitted shade cloth, 70% shading, supplied
10 by Gale Industries, Sandringham, Victoria, Australia.
SAM PLE NO. 3
R~se Material: Silicone rubber, Elastosil~ LR 3001/35 A/B, supplied by Wacker
Chemicals Australia Pty. Ltd., Melbourne, Victoria, Australia
Reinforcing Material: Stainless steel omega wire (single braid), supplied by
15 Wire Mesh Industries, Sydney, Australia.
SAMPLE NO. 4
R~se Material: Polyurethane formulation, Hardness 45, Shore A
Constituent Part byWeight Supplier
Polyol 4701 (polymer polyol) 50 Dow Chemicals Ltd.
Polyol HS 100 (polymer polyol) 50 Union Carbide Chemicals
CereclorAS52 (chlorinated - 50 ICI Chemicals
long chain paraffin hydrocarbon)
Alumina Hydrated 25 AlcoaAustralia Pty. Ltd.
Antimony Trioxide 15 M & T Chemicals, Inc.
25 (99.5% antimony oxide)
Thorcat 535 (phenyl mercury ester) 1 Thor Chemicals (UK) Ltd.
Suprasec VM 25 (isocyanate) 10 ICI Polyurethane Group
Reinforcing Material: Polypropylene knitted shade cloth, 70% shading, supplied
by Gale Industries, Sandringham, Victoria, Australia.
30 SAMPLE NO. 5
Base Material: As per Sample No. 2 (increased thickness)
Reinforcing Material: As per Sample No. 2
WO 95/08935 2 ~ 6 9 4 6 l PCT/AU94/00597
SAMPI E NO. 6
Constructed as per Danton.
Base Material: Compin silicone rubber.
Reinforcing material: reinforcing wire - diameter 0.70mm, coil diameter 6mm.
5 SAMPI ~ NO. 7
Constructed as per Danton
Base Material: Compin silicone rubber
Reinforcin~ Material: reinforcing wire - diameter O.90mm, coil diameter 15mm.
SAMPLE~ NO. 8
10 Constructed as per Ward
Base Material: Hardness 85, Shore A
Constituent Part by Wei~ht Supplier
Polyol HS 100 (polymer polyol) 100 Union Carbide Chemicals
Thorcat 535 tphenyl mercury ester) 1 Thor Chemicals (UK) Ltd.
15 Suprasec VM 25 (isocyanate) 15 ICI Polyurethane Group
Reinforcing Material: 304 stainless steel standard wire mesh, supplied by
Lockers Pty. Ltd., Moorabbin, Victoria, Australia
The results of the tests conducted in accordance with AS 2001.2.9 are
given in Table 1 overleaf.
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WO 95/08935 2 1 6 ~ 4 6 l PCT/AU94/00597
Referring to Table 1 it can be thus be appreciated that vandal resistant
materials made in accordance with the present invention exhibit low flexural
rigidity, which corresponds to high flexibility and drapeability. Typically the
flexural rigidity of the vandal resistant material of the present invention is less
5 than 100 x 103 micronewton-metre. In preferred embodiments of the present
invention the flexural rigidity of the vandal resistant material is less than 30 x 103
micronewton-metre. This represents a significant improvement over known
vandal resistant materials such as those according to Danton and Ward.
It is also notable that preferred embodiments of vandal resistant materials
10 according to the present invention exhibit low bending modulus, preferably less
than 10 micronewton per square metre.
It should also be noted that vandal resistant materials made in
accordance with the present invention exhibit excellent flexibility in both
longitudinal (lengthwise) and transverse (widthwise) directions of the material. It
15 can be understood that the flexibility of a reinforced material such as a vandal
resistant material may vary according to plane and direction in which the
material flexed. However with preferred embodiments of the vandal resistant
material according to the present invention the ratio of greatest flexural rigidity of
the material (i.e. Ieast flexibility) to the least flexural rigidity of the material (i.e.
20 greatest flexibility) is typically less than 2. Also in preferred embodiments of the
vandal resistant material as per the present invention the ratio of the highest
bending modulus of the material to its lowest bending modulus is typically less
than 2.
Preferred methods of manufacturing the vandal resistant material in
25 accordance with the present invention will now be described.
A non-woven crocheted metal reinforcing wire, known as omega wire,
having a thickness of about 1 mm. is placed on one face of a flat mould. The
reinforcing wire is held flat on the mould face either by magnetic force or by
stretching between holding clamps. A flexible high density polyurethane foam
30 mixture, having a final expansion of no more than 1.3 times it's original
unfoamed volume, is poured into the mould and the mould closed to cause the
foam mixture to flow through and surround the reinforcing wire. The flow of the
WO 9S/08935 2 1 6 9 4 6 l PCT/AU94/00597
13
foam material through and around the reinforcing wire is assisted by the small
expansion of the foam as it reacts. The mould is set to provide a thickness of
foam material of 5 mm. Once the material has cured sufficiently the product is
removed from the mould and cured further as is necessary depending on the
specific foam formulation which is used. A soft, flexible, foldable and /or c~p~ble
of being draped vandal resistant material is produced which can be trimmed, if
necess~ry, to size and applied to a seat by known upholstering techniques.
In an alternative method, the same procedure as above is used but a
metal mask of 3 mm. thickness is placed on top of the reinforcing material. The
10 mask is in the form of a metal plate having a cut out portion of a shape
approximating the direct contact face of the seat to which the vandal resistant
material is to be applied with the remainder of the plate approximating to at least
the area and shape of the remainder of the seat including additional areas to
enable attachment of the vandal resistant material to the seat. A foam mixture is
15 introduced into the mould and the mould closed as above. The mask results in a
vandal resistant material having a reinforcing material fully embedded therein in
which the thickness of the material corresponding to the cut-out being about 4
mm. and the remaining thickness being about 1 mm.
In a further alternative the thickness of the mask is tapered from the cut-
20 out portion towards the edge of the mask to provide for a tapering of the
thickness of the vandal resistant material from a thickness in the area of the cut-
out (which corresponds to the direct contact face of the seat) of 4 mm. to a
thickness at the edges (corresponding to the extremities of the other exposed
faces of the seat) of about 1 mm.
In a further alternative the mould may be of a specific three dimensional
configuration to provide a vandal resistant material having a "cup" shape
designed to fit to a particular seat. The mould pieces are dimensioned to mould
a vandal resistant material either having a uniform thickness of e.g. about 4 mm.
over the exposed faces of the seat or having a thickness of 4 mm. at the direct
30 contact face area of the material and having a thickness stepped or tapered to
e.g. about 1 mm. (i.e. the thickness of the reinforcing material) at the other
"exposed faces" area of the material.
WO95/08935 ~ 2 1 6946 1 PCT/AU94/00597
14
In all of the above alternatives the omega wire reinforcing material may
be replaced by a knitted or crocheted synthetic plastics material. Either of thereinforcing materials may be of monofilament construction or may be knitted or
crocheted from a number of monofilaments. The diameter of the monofilaments
5 in the reinforcing material is not critical and may be about 0.275 mm. The
omega wire is produced by a knitting or crocheting process in tubular form. the
wire may be used directly in that "double thickness" tubular form or cut along it's
length and used in a single thickness. The wire is in the form of inter-engagingloops in the form of the greek letter "omega" with a preferred repeat loop unit
10 being 0.6 by 0.6 mm. The particular composition of the monofilarnent be it metal
or synthetic plastics material is not of particular importance. Polypropylene and
stainless steel wire have both been found to produce acceptable vandal
resistant materials.
In manufacturing the vandal resistant material it is preferable that an
15 outer covering of a protective, decorative or wear resistant woven or non-woven
fabric or synthetic plastics sheet material is placed in the mould between the
mould and the reinforcing material with the inner surface of the outer covering
against the reinforcing material and the outer surface against the mould surfaceso that the vandal resistant material is moulded directly on to the outer covering.
20 It is also possible to glue the outer covering to the vandal resistant material. It is
also possible, in the case of a woven woollen outer covering, to glue a thin
flexible compatible sheet material or to apply a thin layer of a compatible
plastics or other barrier material between the outer covering and the reinforcing
material if the elastomer or foam is likely to "strike through" the weave of the25 woollen material.
Thus the vandal resistant materials of the present invention are soft,
flexible and/or drapeable so that they are capable of attaching or fitment to a
wide variety of seat configurations by known seat upholstering methods. The
vandal resistant materials may be fitted to the seats in one or more pieces
30 depending on the specific characteristics of the seat which is to be made vandal
resistant. The vandal resistant materials may be made as a covering material to
be placed over an existing seat or may be made as a covering material to
WO 95/08935 . A j~ 2 1 6 9 4 6 1 PCT/AU94/00597
protect any spring or flexible low density foam cushioning material. The vandal
resistant materials according to the present invention permit the materials to be
fabricated to fit a variety of different and complex seat shapes by known
upholstery techniques whilst providing vandal resistance over the entire
exposed seat cushion area and additionally providing an improved degree of
user comfort, particularly by avoiding the necessity of including moulded rigid
plastics or other rigid materials in contact with the user of a seat upholsteredwith or otherwise made from a vandal resistant material made in accordance
with this invention .
