Note: Descriptions are shown in the official language in which they were submitted.
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Terry fabric panels
The invention relates initially to a panellike building
element comprising a first and second layer and an interlayer
preferably of a foam disposed therebetween, the first and second layers
being formed on the basis of a textile material. Such a panellike
building element is known for example from DE-A-21 38 705. In this
known building element, the outer layers are formed of composite films.
Such a building element is considered in need of improvement
particularly as regards its delamination properties.
Reference is also made to U.S. Patent Specification 4,888,228
as state of the art. From this document, there is known a fully cured
resinated building element having solid continuous panellike
resination, fabric layers being provided which, by virtue of
stitched-in threads, form loops or free-standing ends protruding into
the resinating material. The loops or free-standing ends of the fabric
layers overlap one another. Further state of art is formed by the
documents of DE-U-90 07 289 as filed. Similarly to the aforementioned
U.S. patent specification, there is here provided a fabric layer which
forms free-standing tufts or cut threads and which layer is then, in
conjunction with fully such fabric layers, fully impregnated with a
matrix plastics for a continuous solid construction.
Against the background of the state of the art described
above, it is an object of the present invention to provide a panel-like
building element which is as light in construction as possible, which
has a middle layer of freely foamed synthetic resin, especially an
open-celled foamed synthetic resin, and which has a minimal tendency to
delaminate.
This object is achieved initially and substantially by the
subject of Claim 1, by which it is provided that the first and/or
second layer of the panel-like building-element is formed of a cured
resinated fabric, which fabric forms projecting extensions, and these
projections in addition facing the opposite layer and by protruding
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into the intérlayer formed of foam, causing the layers to be secured to
one another. In contradistinction to the cited state of the artl the
panellike building element according to the invention is not formed by
overall impregnation (or foaming) with a single foam material; on the
contrary, the outer layers, which form the cover layers of the
panellike building element, are separately cured resinated panellike
elements having the aforementioned extensions, which are only joined to
one another to form a strong lightweight sheetlike building element
when a further foam material is expanded between the layers, i.e. by
means of the interlayer formed of foam. However, the interlayer need
not necessarily be a foam. It may also be some other material which is
for example initially liquid and then cures, thus a resin, for example.
What is essential, however, is that the first and second layers be
initially separately cured resinated fabrics, precisely in order for
the formation of the extensions and their automatic uprighting to take
place. The fabric too preferably has looplike extensions. A terrylike
fabric is particularly suitable. It is also preferable for the fabric
to comprise an industrial yarn such as carbon fibre, aramid fibre,
ceramic fibre or especially glass fibre. The foam is preferably formed
of a foamable resin. Recommended examples of the foamable resin are
polyurethane-based, epoxy-based, phenol-based and polyester-based
resins. Especially those which form open-celled foams. The
intersecurement of the layers in the product according to the invention
is so effective that attempted delamination will result in a rupture
occurring in the foam, but not directly between the fabric layer and
the foam. For this it is also preferable that the extensions have a
certain effective free length. This length is preferably within the
range from 1 to 10 mm.
A further subject of the invention is also a terrylike fabric
which comprises an industrial yarn such as carbon fibre, aramid fibre,
ceramic fibre and especially glass fibre and has free-standing cured
loops as a result of curable resination. In connection with, for
example, terrylike fabric woven from glass fibres having loops of the
type in question on the upper surface (although the loops may also be
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formed on both sides), it has surprisingly been found that, on curable
resination, these loops automatically assume a standing position, so
that they extend substantially perpendicularly or only at a slight
angle of inclination relative to a plane in which the base layer of the
fabric extends. Such a cured terrylike fabric is also widely usable
on its own. For instance, it is in particular capable of bending
while at the same time, by virtue of the standing loop structures,
having integrated spacers. This may be utilized for example in a curved
building element for maintaining a spacing from a second layer to leave
a clear space through which a medium, for example air, can flow. The
cured resinated fabric in question is still surprisingly bendable. It
can therefore be utilized for sheathing even tubelike articles in
particular. It can then be adhered in the wound form to the outer
surface of the tube by means of an adhesive/resin. Also conceivable is
an overlapping wrap in which the adherence/securement is immediately
effected on the back of the resinated cured fabric. Also of importance
is the immediate use of a terrylike fabric, especially on the basis of
an industrial yarn, for forming a building element through curable
resination. In a further embodiment, it is also provided that the
fabric, when formed on the basis of an electrically unconductive or
virtually unconductive base material, has individual threads which are
electrically conductive, such a thread also forming a loop or coil. For
example, the fabric may consist of glass fibre as base material. As
electrically conductive thread, there can then be introduced a carbon
thread which in fact also forms a loop or coil. In a practical
embodiment, such a conductive thread is then introduced at regular
spacings distributed over a fabric surface. Reference is also made in
this connection to W092/17661 from which it is already known for a
two-layered spacer fabric to introduce into a base fabric a conductive
thread floating between the layers. In a fabric of the type in
question here, however, the conductive thread does not alternate
between two layers of a double-layered fabric but it extends in the
base fabric and at least to some extent in loops formed therefrom.
The conductive thread may then also leave out certain loops. It is
possible as it were for an interloop of conductive fibre to be
introduced into the grid of the base fabric.
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The invention also relates to a building element based on a
cured resinated loop fabric such as particularly a terrylike fabric,
wherein two fabric layers are joined to each other by the resination
with the loops facing one another. By this, loops hardened by
resination form the spacing elements. Although filling the free space
then otherwise remaining between the base fabric layers is possible, in
many applications, for example when the interspace is to be utilized
for leakage monitoring (cf. EP W0/92/17661), it is not necessary or
desired. The building element is characterized by external, thin r
substantially unbroken, resinated base fabric layers, from which
loop-like, i.e. substantially circular, structures extend in a large
multiplicity inward, towards one another. By the curing resination,
which also joins the two fabric layers to one another, a high- strength
building element is created. In this way, it is possible, on the one
hand, for the looplike structures to be substantially provided in such
a way that they meet head on, as it were. In addition, however, it is
possible by pressing these fabric layers into one another - especially
if in a first operation, these have already been separately resinated
and cured - to reach saturation of the looplike structures in a second
operation and join them to one another once more with resin in this
saturated layer, an even more compact and stronger building element
being achieved.
As regards the loop fabric described, which may also be called
a coil fabric~ it is essential that the loops or coils are created as
an integral part of the weaving process. They are formed to belong to
the woven fabric structure.
A subject of the invention is also an article such as, for
example, a tank, a panel element, a tube or the like, having an outer
lining, covering or sheathing, a coating, for example of a resin
material, being applied to a surface of the article, and a spacer
element having an unbroken cover layer with projecting extensions lying
on top of the coating in such a way that a void remains between the
surface and the projecting extensions. In this connection, reference
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is to be made for example to EP-B 169 303. The known lining still has
a relatively costly construction. The invention proposes in this
context that the extensions have a looplike or coillike construction
and be secured to the article by the coating. The coating may thus be
for example an epoxy resin layer or the like. The spacer element with
the looplike or coillike extensions is pressed into the still soft
epoxy resin layer and the desired securement is achieved by the curing
of the epoxy resin layer. In a further embodiment, it may also be
provided that the extensions are embedded in the coating to provide a
positive hold. Since the extensions are looplike or coillike, the
coating can penetrate the free cross-section of the loop - preferably
partially - and so enclose the loop or coil at least partially
completely. A particular embodiment provides that the coating is
conductive. Especially in combination with a spacer element which is
itself conductive, for example a glass fibre fabric having conductive
threads, as has been described further above, this makes possible a
coating and simultaneous monitorability, for example, of tanks, both
the coating and also the spacer element simultaneously providing the
requisite explosion security through the conductivity. In this
connection, reference is to be made to W0 92/17661 from which there is
already known a different lining for a tank, with monitorability of the
void created and a conductive set-up of the spacer element.
The invention is described in more detail below, but only by
way of example, with reference to the accompanying drawings, in which:
Fig. 1 shows a cross-section through a panellike building
element formed from two oppositely disposed cured resinated loop fabric
panels and foaming of the interspace;
Fig. 2 shows a perspective view of a cured resinated loop
fabric;
Fig. 3 shows a cross-section through a buiIding element formed
from two cured resinated loop fabric panels directly disposed on one
another with their loops;
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Fig. 4 shows d cross-section through a loop fabric in cured
resinated form, which has loops on both sides,
Fig. 5 shows a cross-section through the article according to
Fig. 2, sectioned along the line V-V;
Fig. 6 shows a partial sectional depiction of a fabric panel
depicted as shown in Fig. 2 as a spacer element on a wall portion;
Fig. 7 shows a section through the article according to Fig.
6, sectioned along the line VII-VII.
There is first of all shown and described with reference to
Fig. 1, a cross-section through a building element 1 having a
sandwichlike construction. As bottommost layer 2, there is provided a
cured resinated loop fabric, and as uppermost layer 3, a similarly
cured resinated loop fabric. The interspace is filled by a freely
expanding foam material which is open-celled in the solidified state
and which accordingly forms an interlayer 4. It is a rigid foam. As a
result of the fact that the foam of the interlayer 4 completely
surrounds the projecting extensions of the layers 2, 3, namely the
loops 5, and also penetrates into these, the overall result is a very
intensive securement of the interlayer 4 to the fabric panels of the
layers 2 and 3. There is no possibility of any delamination of a fabric
- 25 panel from the foam of the interlayer 4. On the contrary, a breaking
test shows that any break occurs in the region of the free foam, beyond
the loops 5. The subsequent description of the building elements
according to Figures 2 to 5 is similarly important as regards the cured
resinated loop fabric of the layers 2 and 3 of the building element 1.
More particularly, the loop fabric of the layers 2 and/or 3 may also be
a loop fabric as depicted in Fig. 4.
In Fig. 2, a fabric panel 2 or 3 in cured resinated form is
shown in perspective view. A multiplicity of loops 5 are visible. The
fabric, which is terrylike or a customary terry fabric, is made on a
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base of glass fibres. The loops, which are arranged to be flat or only
slightly upright following weaving, have been stiffened by sufficient
impregnation, including for example spraying the fabric with a resin,
for example an epoxy resin, so that they cannot for example be
compressed or even folded over by hand. Similarly, excess resination
with a subsequent squeeze-out to a desired resin content is possible.
The depicted spacing disposition of the loops is obtained automatically
on resination.
In the representation of Fig. 2, schematic resination
accumulations 6 at the base regions of the loops 5 are shown. Also
resinations 7 r which can appear between neighbouring loops 5 at their
point of contact. The loops 5 and the underlying glass fibre fabric
generally also have a sleevelike overall coating of resin, which in
fact leads to the integral stiffness of a loop 5 in the manner
described. The resinations 7 are also dependent on the diameter of the
loops, which is adjustable. A height or free length l of the loops 5
can likewise be freely adjusted in principle. In practice, such a
length l in the range from 1 to 10 mm has been found to be essential.
It can also be seen that the loops extend in the manner of
helical sections; that is, that a first foot 8 is offset in a depth
direction t of the panel relative to a second foot 9.
The lower panel 10 is formed by the curable resination of the
base fabric layer from which the loops protrude. The panel 10 is
generally liquid-tight. Depending on the resin used, the building
element of Fig. 2 may also be constructed to be translucent as a whole.
Figures 3 to 5 depict cross-sections through various
embodiments of a building element based on a base element in accordance
with the representation of Fig. 2.
In this regard, Fig. 5 represents a front view of the building
element according to Fig. 2 in the direction of the arrow V in Fig. 2.
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Fig. 3 represents a cross-section through a building element
obtained by superposing two building elements of the type depicted
according to Figures 2 and 5. The superposing has been effected in such
a way that the loops rest on top of one another at their upper ends. It
is evident that by the process of resination, there are formed further
resin bridges 11, 12 between opposite loops 5, 5' and 5". Owing to the
helical configuration of the loops, it is also possible, especially
following a certain offsetting of the layers relative to each other,
for an upper loop 5' to be secured via (lateral) resin bridges to two
further loops 5 of the lower layer.
The cross-section according to Fig. 5 shows a building element
formed of a terrylike or terry fabric which has been resinated and
cured, wherein for the terry fabric, loops are formed on both sides,
which here lead to rigid loop structures 5 on both sides.
A building element 1 as depicted in Fig. 1 is manufactured by
first resinating and curing appropriate fabrics, i.e. terrylike fabrics
in particular, for the layers 2 and 3, either in a continuous process
or directly as panel elements, then disposing these layers 2, 3
opposite each other in a mould and applying a freely foaming resin to
the lower layer 2. The desired spacing between the layers 2 and 3 is
then set in the mould and the freely foaming resin fills out the
interspace to effect formation of the interlayer 4. In the course of
its free foaming, the resin also penetrates at the same time into the
region of the loops 5, penetrating both the interspaces between the
loops and into the loops 5. What is essential is the integral
positive bond ultimately achieved by this between the interlayer 4 and
the upper and lower layers 2, 3. (It is of course also possible to
construct the building element only with one layer 2 and a resin layer
applied thereto, which becomes a foam layer). In contradistinction to
known panel building elements, there is no need for any adhesive bond
between the layers 2, 3 and the interlayer 4 and neither is this in
fact readily achievable as part of the manufacturing process.
21 88401
The base fabric layers which lead to the panel 10, for example
as part of the building element according to Fig. 2, may also be
multilayer fabrics on their own, if appropriate further reinforcement
is additionally desired. It is also possible to provide further
reinforcement with further fabric or mat layers in superposition. It is
preferable for these to be coproduced integrally at the same time in
the course of the making of the loop fabric.
If an edge reinforcement is desired for the resulting building
elements, especially a building element 1 in accordance with Fig. 1,
this may be immediately achieved in a very simple manner and way by
placing for example edge strips, aluminium sections, corner
reinforcements or the like in the mould. In fact, the mould itself may
even be used as final profile, so that a strong frame encloses the
panels.
In Fig. 6, a partial cross-sectional view of a tank lining is
shown. A resin layer 14 is applied to the tank wall 13. In the
uncured state of the resin layer 14, a panel portion according to Fig.
2 has been pressed into the resin layer 14 with the loops 5 pointing
downward. The resin layer 14 thereby completely encloses the loop
structure in the tip region of a loop 5, as is evident from Fig. 7 in
particular. This provides an intensive positive securement of the cured
resinated building element of Fig. 2 to the tank wall 13. It further
creates a continuous void 15 which may be utilized for the
above-mentioned monitoring duties.
The terrylike fabric is especially suitable for such linings,
since it is flexible and thus can easily be conformed to a curved
surface of a tank or the like.
The features of the invention disclosed in the foregoing
description, the drawing and the claims may be important not only
individually but also in any desired combination for realizing the
invention. All disclosed features are essential to the invention. In
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the disclosure of the application, there are hereby also incorporated
as to their full content the disclosure content of the
corresponding/accompanying priority documents (copy of the prior
application).
