Note: Descriptions are shown in the official language in which they were submitted.
_ackground of the Invention
This invention relates to a process of manu-
facturing a heat-insula-ting building board, which
consis-ts of at leas-t one pla-te of heat-insulating
material, which is enclosed by a reinforcing material
which ensures the required s-treng-th.
The desire for energy-saving buildings and
for a subsequent applica-tion of heat-insulating layers
in residential buildings has resulted in an enormous
increase of the demand for various insulating ma-terials,
such as insulating boards and insulating mats. The
desire for elemen-ts and boards which are weather- and
ire-resistant and dimensionally stable and have a high
- bending strength is continuously increasing.
There are numerous effective insulating
materials in the form of elements and boards bu-t none
are known which are weather- and fire-resis-ting and
dimensionally stable and have a high bending strength.
For this reason it is not possible to use a material
of one kind for various purposes/ e.g., for walls
and ceilings of a garret and for insulating a flat
roof, a facade or a wall or for making a partition.
The requirements are so different tha-t -the properties
of a single matexial are not sufficient. Austrian
Patent Specification 322,165 describes process of
manufacturing boards, plates or shaped eIements which
have a heat-insulating core that is surrounded by a
hydraulic binderr such as gypsum. The process is used
for the continuous manufacture of a strip ~hich is, eOg.,
0.6 meters wide and 7 centimeters high and which is
finally cut into plates or boards having a desired
length so that the binder does not cover the end faces.
The process comprises a plurality oE steps. The core
is first inserted into a mold, which consists of a con-
veyor belt and laterally disposed rubber belts. In
the next s-tep the laterally disposed rubber belts
diverye and the gypsum pulp is poured into the laterally
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widening space so that the core is lifted by bouyancy
until it engages a pressure roller, which limits the
lifting of the core. The gypsum plaster is introduced
in such a manner -tha-t it encloses the core to about
one-half of its height. When the gypsum plaster has
hardened, the pressure roller is removed and additional
gypsum pulp is poured in until the la-tter has risen
to the upper edge of the laterally disposed rubber belts
and entirely covers the core. That second layer is
then hardened. Because the second gypsum layer is
not applied until the first gypsum layer has hardened,
a monolithic joint between the two layers is not
obtained so tha-t the mechanical strength is lower than
that which would be ensured by a homogeneous joint.
Summar~ of the Invention
The disadvantages encountered in the
manufacture of building boards of the known kind can
be eliminated by the heat-insulating building board
according to the invention.
It is an object in the invention to provide
a proc ss of manufacturing individual heat-insulating
building boards which consist of a composite that meets
the above-mentioned requirements, has a high bending
strength and can be made in a small number of working
steps.
The process of manufacturing a building board
of the kind mentioned first hereinbefore is characterized
according to the invention in that the reinforcing
material is introduced as a pulp into a vertical mold
so as to fill the latter only in part and -the plate
is then preferably centrally immersed into the partly
filled mold and is held in position so that the pulp
is displaced by the plate and encloses the latter.
According to another feature of the invention
the p]ate and/or the mold is vibrated as the plate is
immersed into the pulp so that the friction between the
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plate and the pulp is reduced and -the wettiny of the
plate by the pulp is improved. For improved wettiny,
the invention teaches -to moisten the plate and/or to
apply a wetting agen-t -to the plate before it is
imme-ised into the pulp. Another feature of the invention
resides in that the reinforcing material contains
binders which harden hydraulically and/or with
carbonation and are mixed with water to form a pourable
pulp, which when hardened has a density of 400 to
2500 kg/m3.
According to another feature of the invention
the reinforcing material contains inorganic and~or
organic synthetic fibrous materials and/or natural
fibrous materials, fiber mates, fiber meshes or the
like, as well as water-soluble modified plastic materials,
air-entraining agents, foam stabili~ers, fine-grained
admixtures and color pigments.
2Q An additional feature of the invention resides
in that the plate consists of synthetic organic products,
such as polystyrene, polyurethane, foamed phenol
resin, foamed rubber or similar foams, which have in
the dry state a density below 200 kg/m , preferably
below 40 kg/m3.
Also in accordance with the invention the
plate may consist of natural organic products, such
as straw, reed, coconut fiber, wood fiber, sawdust,
cork, ri~e shells, raw cotton or the like, which in
the form of plates have in the dry state a density below
400 kg/m3, preferably below 200 kg/m3.
According to a further feature of the
invention, the plate consists of inorganic products,
such as expanded perlite, vermiculite, expanded clay,
expanded shale, granulated ash, foamed silicate, foamed
water-glass, glass wool, mineral wool, crushed foamed
slag or the like, which in the form of plates
have in the dry state a density
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below 600 kg/m3, preferably below 300 ky~m3.
Also in accordance with the invention the
plate is formed at its ends with steps or with a tongue
and groove. These formations may subsequently be
formed by milling.
In one aspect the invention provides a
process for manufacturing a heat-insul.ating building
board, which includes at l~ast one plate of heat-
insula-ting material enclosed by a reinforcing material
which ensures the required strength, said method
comprising: providing a mold; orienting the mold with
its longest interior dimension ex-tending vertically;
introducing a hardenable reinforcing ma-terial as a
pulp into the mold so as to fill the mold to a pre-
determined volume so tha-t the mold is filled only in
part; di~pl~ing the plate into the L~artly filled m~ld
and holding it in posi~tion so that the pulp is displaced
hy the plate and encloses the latter; permi-ttin~ the
reinforcing material to ~arden~ and removing the
finished board from the ~old.
Illustrative embodiments of the invention
will now be explained with reference to the drawings.
.
Brief Description of the Drawings
Figure 1 is a -transverse sectional view
taken at right angles to the longitudinal direction of
the building board and shows a first illustrative
embodiment of a building board according to the invention.
Figure 2 is a similar view showing a second
embodiment of a building board according -to the inven-
tion;
Figure 3 is a similar view showing a third
illustrative embodiment of a building board according
to the invent.ion;
mab/`f
Figure 4 is a similar view showing a fourth
embodiment of a building board accordiny to the
invention;
Figure 5 is a similar view showing a fifth
embodiment o a building board according to the
invention;
Description of the Preferred Embodimenks
Figure 1 shows a heat-insulating plate 1,
which just as in the o-ther embodiments, shown in
Figures 2 to 5, may consist of syn-the-tic organic
products, such as foamed polystyrene, foamed polyurethane,
foamed phenol resin, foamed rubber or similar foams,
which have in a dry sta-te a density ~elow 200 kgJm3,
preferably below 40 kg/m3. Al-ternatively, the plate 1
may consist of natural organic produc-ts, such as s-traw,
reed, coeonut fiber, wood fiber, sawdus-t cork, rice
hulls, raw cotton or the like, which in the form of
plates have in a dry state a density below 400 kg/m3,
preferably below 200 kg/m3. These materials can also
; be used for making the plate 1 shown in Figures 2 to
5~
Finally, -the plate 1 shown in Figures 1 to
5 may be made from inorganic products, sueh as expanded
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perlite; vermiculite, expanded clay, expanded shale,
granulated ash, foamed silicate, foamed wa-ter-glass~
mineral wool, crushed ~oamed slay, glass wool or the
like in the form of a prefabricated element consisting
of any of these produc-ts or a combination thereof.
The plates can be prefabricated in that the
abo~e-mentioned materials are processed together with an
inorganic binde~, such as Port:land cement, high-alumina
lO cement, aluminum cement, hydrophobic cement, gypsum,
hydraulic lime, slaked lime, or with other binders, such
as spent sulfite liquor cellulose products, or water-
soluble plastics materials, to form prefabricated plates.
The material 2 surrounding the plate l serves
as a support and is dimensionally stable and fire- and
weather-resisting. It may preferably consist of binders
whîch harden hydraulically and/or with carbonation, such
as Portland cement, natural cement, slaked lime, hydro-
20 phobic cement, white cement, or plastic-modified forms of
said materials in a pure form or with fine-grained frost-
and fire-resisting admixtures, preferably in particle
siæes below lO mm. To improve the heat insulation, the
invention calls for incorporating an air-entraining agent
in a cement paste or mortar obtained by mixing said
materials with water. Fibers 3 may be admixed to improve
the dimensional stability and the bending strength. The
fibers 3 consist of individual or interlaced inorganic
and/or organic synthetic and/or natural fibrous materials,
30 fiber mats, fiber meshes or the like, which in the process
according to the invention are added during the preparation
of the cement paste or mortar or are added thereto in
the mold before hardening takes place.
In the embodiment shown in Figure l, the mold
used to manufacture the building board may have in its
bottom a trapezoidal recess so that the corresponding
portion of the building board is formed with a trapezoidal
tongue.
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A corresponding groove can be formed in the
upper end face of the building board, e.g., in that the
mold is provided beEore the hardening of the mater-ial
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with a cover which has a correspondiny -trapezoidal recess.
In -that case much fewer dowels will be required to fix
the insulating board to masonry and the fixing means
will not injure the visible surface.
The building boards shown in Figure 2 may be
formed in a similar manner with a semicircular tongue.
The complementary semicircular groove may be ormed, e.g.,
in the heat-insulating plate 1. The joints be-tween
adjoining building boards may be improved in accordance
with Figure 2 in that a fixing strip 3a consis-ting, e.g.,
of fibrous material, is embedded in the reinforcing
material. Alternative fastening means consist of
individual lugs, plates or hooks 3b, which are anchored
in the building board, as shown in Figure 3. Where a
building board is provided with such additional fastening
means, the adjoining board will be provided with a mating
recess 4 for accommodating the fastening means. The
board may be provided on its exposed surEace with a colored
and/or structured layer, which may be obtained by an
addition of fine-grained admixtures and/or color pigments
to the material 2. In the embodiment shown in Figure 3,
the bottom surface of the mold is complementary to the
recess 4 and the protruding plate 1. Besidesl the cover
of the mold is provided with a recess which corresponds
to the width of the plate 1.
In the embodiment shown in Figure 4, the plate
1 is pro~idedJ e.g., with dovetail grooves and is immersed
into the pulp in contact with the right-hand inside
surface of the mold. The mold is provided at the bottom
with a step 4a so that the material 2 does not reach the
bottom. As a result, the finished building board has a
recess 4a, which can receive the protruding portion 5 of
the hardened material 2 of an adjoining building board as
the building boards are assembled. The cover of that mold
has a recess which has the same width as the plate 2 so
that the material 2 Eorms the protruding portion 5 at the
top.
The embodiment shown in Figure 5 is similar
to that of Figure 3 but comprises two plates 1. The mold
and its cover are so shaped that two recesses are obtained
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on the top end face of the finished building board and may
receive two pla-tes 1 protruding from the lower end face
of an adjacent building board as the building boards are
asser~led.
The process according to the :invention for the
manufacture of heat-insulating boards will now be e~plained
more fully with reference to examples, to which the
invention is not restricted.
Example 1
The ma-terial 2 consisted of a cement paste which
was based on Portland cement and contains 0.1~ air-
entraining agent and 2.0% by volume fibers. That paste
was stirred under superatmospherie pressure in a forced
circulation mixer rotating at high speed to form a mix of
high porosity, which was poured into a vertical mold.
The mold was filled to such an extent that it was filled
to its top edge by the subsequent immersing of a poly-
styrene board 5 cm thic7c into the material 2 so that the
latter was displaced. The extremely lightweight polystyrene
plate 1 was held against floating up by a mounting provided
on the end facès or the longitudinal edges and against a
lateral slipping by a guide. The plate 1 was held in the
mold until the material 2 had hardened. The mold caused
the material 2 to form a tongue and groove. When the
material 2 had hardened, the resulting building board
ha~ing dimensions of, e.g., lOOx60x8 centimeters, had a
spacific gravity of 300 kg/m3 and the average ultimate
load with an effectîve span of 50 cm amounted to 80 kg.
Example 2
To make the material 2, a basic mixture con-
sisting of 9 parts by weight of foamed polystyrene spheres
0.2 to 3.0 mm diameter and 91 parts by weight was stirred
with water and 0u3% air-entraining agent in a forced
circulation mixer. The material was poured into a
vertical mold, into which a close-mesh glass fiber mat
was immersed, e.g., at the edge, as a plate 1. The
pressure applied by the material 2 forced the glass fiber
mat against the wall of the mold so that the mat served
virtually as a filter preven-ting a movement of the poly-
styrene particles to the outside. This resulted in the
formation of an outer layer consisting of cement paste
reinforced with glass Eibers,
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and of a core layer consisiing of cement-bonded polystyrene.
The plate 1 remalned in the mold un-til the materia~ 2
had hardened. A building board made in this manner and
having dimensions of 150 x 60X 8 centime~ers had a specific
gravit~y of 350 kg/m~.and wi-th an effective span of 50 cn
had an average ultimate load of 100 kg.
Example 3
Formula for material 2:
Expande~ perlite, particle size 0~0 to 3~0 mm 5.0 ~/0 by weight
Expanded clay (500 g/liter), particle size
3Ø to 10.0mm 95.0 % by weight
Cement content 350 kg/m3
Water cement ratio 0.7
Air-entraining agent: 0.3 % by weight of the cement.
Mixing was effected in a forced circulation
mixer so that the cement paste which contained the perlite
was prepared first and the expanded clay was subsequently
admixed for a short time. rrhe resulting mix was poured
into a vertical mold. A mat of synthetic fibers was{sub-
sequently immersed int~ the mold and held in po~etio~ by
the means described in Exarnple 1. The resulting building
board having dimensions of 120 60 8 centimetPrs had a
specific gravity of 600 kg/m3 and wi-th an effective span
of 50 cm had an average ultimate load of 200 kg~
In the examples mentioned above) the heat-
insulating material could be introduced into the mold
first 7 fol~owed by the introduction of the reinforcing--
material as a pulp. But air-bubbles may then be included
and would reduce the strength of the finished building
board. The danger is avoided by the process according to
the invention, which results in an intimate hond between
the two materials so that a high strength is ensured.
other advantages afforded by the building
board according to the invention over conventional boards
reside in that they have a very wlde field of applica-tion
because they resis-t water and fire and have a high bending
strength. For instance, they can be used to insulate basement
walls and facades, or as lost formwork in the making of
concrete walls and f~oors, as walls and ceilings of garrets,
and as partitions between rooms, also ins-tead of wood in
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the erection of barns ahd huts9, where the fire risk is
very high. In all these uses, all embodlments have a
sur.face which corresponds to a final plaster coat or may
be used as a plaster base for a ready-mixed colored external
plsster.
