Title of Invention

MINERAL WOOL COMPOSITION

Abstract Mineral wool capable fo dissolving in a physiological medium ,which mineral wool comprises the constituents below in the following percentage by weight: SiO2 39-55% preferably 40-52% Al2O3 16-27% "" "" 16-25% CaO 3-35% " " 10-25% MgO 0-15% " " 0-10% Na2O 0-15% " " 6-12% K2O 0-15% " " 3-12% R2O(Na2O+K2O)10-17%" " 12-17% P2O5 0-3% " " 0-2% Fe2O3 0-15% " " B2O2 0-8% " " 0-4% TiO2 0-3% " " and in that MgO is between O and 5% especially between 0 to 2% when R2O<13.0%.
Full Text MINERAL WOOL COMPOSITION
The present invention relates to the field of artificial mineral wools. It is aimed more particularly 5 at mineral wools intended for manufacturing thermal and/or acoustic insulation materials or soilless-culture substrates.
It concerns more particularly mineral wools of the rock-wool type, that is to ^say the chemical
10 compositions of which wools involve a high liquidus temperature and a high fluidity at their fiberizing; temperature, combined with a high glass transition temperature.
Conventionally, this type of mineral wool is
15 fiberized by so-called "external" centrifuging processes, for example of the type of those using a cascade of centrifuging wheels fed with molten material by a static delivery device, as described in particular in Patents EP-0,465,310 or EP-0,439,385.
20 The so-called "internal" centrifuging
fiberizing process, that is to say that using centrifuges rotating at high speed and drilled with holes, is, on the other hand, conventionally reserved for fiberizing mineral wool of the glass-wool type,
25 schematically having a composition richer in alkali metal oxides and having a low alumina content, a lower liquidus temperature and a higher viscosity at the fiberizing temperature than rock wool. This process is described, in particular, in Patents EP-0,189,354 and
30 EP-0,519,797.
However, technical solutions have recently been developed which make it possible to adapt the internal centrifuging process to the fiberizing of rock wool, especially by modifying the composition of the
35 constituent material of the centrifuges and their operating parameters. For further details on this subject, reference may be made especially to Patent WO 93/02977. This adaptation has proved to be particularly beneficial in the sense that it allows

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properties which hitherto were inherent in one or other of the two types of wool - rock wool or glass wool - to be combined. Thus, the rock wool obtained by internal centrifuging has a quality comparable to that of glass 5 wool, with a lower content of unfiberized material than rock wool obtained conventionally. However, it retains the two major advantages associated with its chemical nature, namely a low chemicals cost and a high temperature withstand capability.
10 There are therefore now two possible ways of
fiberizing rock wool, the choice of one or other depending on a number of criteria, including the quality level required for the intended application and the level of industrial and economic feasibility.
15 To these criteria have in recent years been
added that of biodegradability of mineral wool, namely its ability to be rapidly dissolved in a physiological medium, so as to prevent any potential pathogenic risk associated with the possible accumulation of the finest
20 fibres in the body by inhalation.
One solution to the problem of choosing the composition of a rock-type mineral wool having a biosoluble nature consists in the use of a high content of alumina and moderate alkali contents.
25 This solution results in particular in high raw
materials costs because of the preferred use of bauxite.
The object of the present invention is to improve the chemical composition of rock-type mineral
30 wools, the improvement being aimed especially at increasing their biodegradability with the ability for them to be fiberized especially and advantageously by internal centrifuging, while still maintaining the possibility of obtaining these compositions from
35 inexpensive raw materials.
The subject of the invention is a mineral wool capable of dissolving in a physiological medium, which mineral wool comprises the constituents below in the following percentages by weight:

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SiO2 39-55%, preferably 40-52%
A12O3 16-27%, " " 16-25%
CaO 3-35%, " " 10-25%
MgO 0-15%, " " 0-10%
Na2O 0-15%, " " 6-12%
K2O 0-15%, " " 3-12%
R2O (Na2O + K2O) 10-17%, " " 12-17%
P2O5 0-3%, " " 0-2%
Fe2O3 0-15%,
B2O3 0-8%, " " 0-4%
TiO2 0-3%,
and in that MgO is between 0 and 5%, especially between
0 and 2%, when R2O According to an advantageous embodiment of the 5 invention, the mineral wool comprises the constituents
below in the following percentages by weight:
SiO2 39-55%, preferably 40-52%
A12O3 16-25%, " " 17-22%
CaO 3-35%, " " 10-25%
MgO 0-15%, " " 0-10%
Na2O 0-15%, " " 6-12%
K2O 0-15%, " " 6-12%
R2O (Na2O + K2O) 13.0-17%,
P2O5 0-3%, " " 0-2%
Fe2O3 0-15%,
B2O3 0-8%, " " 0-4%
TiO2 0-3%,
In the rest of the text, any percentage of a
constituent of the composition should be understood to
mean a percentage by weight and the compositions 10 according to the invention may include up to 2, or 3% of
compounds to be considered as unanalysed impurities, as
is known in this kind of composition.
The selection of such a composition has allowed
a whole raft of advantages to be combined, especially 15 by varying the many and complex roles that a number of
these specific constituents play.

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It has in fact been able to be shown that the combination of a high alumina content, of between 16 and 27%, preferably greater than 17% and/or preferably less than 25%, especially less than 22%, for a sum of 5 network formers - silica and alumina - of between 57 and 75%, preferably greater than 60% and/or preferably less than 72%, especially less than 70%, with a high amount of alkalis (R2O: soda and potash) of between 10 and 17%, with an MgO content of between 0 and 5%,
10 especially between 0 and 2%, when R2O 15 the embodiments of the invention, the alkali content is preferably greater than 12%, especially greater than 13.0% and even 13.3%, and/or preferably less than 15%, especially less than 14.5%.
This range of compositions proves to be
20 particularly beneficial as it has been able to be observed that, contrary to the received opinions, the viscosity of the molten glass does not drop significantly with increasing alkali content. This remarkable effect makes it possible to increase the
25 difference between the temperature corresponding to the viscosity for fiberizing and the liquidus temperature of the phase which crystallizes, and thus to considerably improve the fiberizing conditions, and especially makes it possible to fiberize a new family
30 of biosoluble glasses by internal centrifuging.
According to one embodiment of the invention, the compositions have iron oxide contents of between 0 and 5%, especially greater than 0.5% and/or less than 3%, especially less than 2.5%. Another embodiment is
35 obtained with compositions which have iron oxide contents of between 5 and 12%, especially between 5 and 8%, which may allow mineral-wool blankets to exhibit fire resistance.

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Advantageously, the compositions according to the invention satisfy the relationship:
(Na2O + K20)/A12O3 > 0.5, preferably {Na2O +
K2O) /A12O3 > 0.6, especially (Na2O + K2O)/A12O3 > 0.7,
5 which appears to favour the obtaining of a temperature
corresponding to the viscosity for fiberizing which is
greater than the liquidus temperature.
According to a variant of the invention, the compositions according to the invention preferably have
10 a lime content of between 10 and 25%, especially greater than 12%, preferably greater than 15% and/or preferably less than 23%, especially less than 20%, and even less than 17%, combined with a magnesia content of between 0 and 5%, with preferably less than 2%
15 magnesia, especially less than 1% magnesia and/or a magnesia content of greater than 0.3%, especially greater than 0.5%.
According to another variant, the magnesia content is between 5 and 10% for a lime content of
20 between 5 and 15%, and preferably between 5 and 10%.
Adding P2O5, which is optional, at contents of between 0 and 3%, especially greater than 0.5% and/or less than 2%, may allow the biosolubility at neutral pH to be increased. Optionally, the composition may also
25 contain boron oxide which may allow the thermal properties of the mineral wool to be improved, especially by tending to lower its coefficient .of thermal conductivity in the radiative component and also to increase the biosolubility at neutral pH.
30 Optionally, TiO2 may also be included in the composition, for example up to 3%. Other oxides, such as BaO, SrO, MnO, Cr2O3 and ZrO2, may be present in the composition, each up to contents of approximately 2%.
The difference between the temperature
35 corresponding to a viscosity of 102*6 poise (decipascal.second) , denoted Tiog 2.5, and the liquidus of the crystallizing phase, denoted Tiiq, is preferably at least 10°C. This difference,- Tiog 2.5 - Tiiq, defines the "working range" of the compositions of the

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indention, that is to say the range of temperatures within which it is possible to fiberize, most particularly by internal centrifuging. This difference is preferably at least 20 or 30°C, and even more than 5 50°C, especially more than 100°C.
The compositions according to the invention have high glass transition temperatures, especially greater than 600°C. Their annealing temperature (denoted Tanneaiing) is especially greater than 600°C.
10 As mentioned above, the mineral wools have a
satisfactory level of biosolubility, especially at acid pH. Thus, they generally have a rate of dissolution, especially measured with regard to silica, of at least 30 and preferably of at least 4 0 or 50 ng/cm2 per hour
15 measured at pH 4.5.
Another very important advantage of the invention concerns the possibility of using inexpensive raw materials for obtaining the composition of these glasses. These comoositions mav esoeciallv result from
20 the melting of rocks^. for 'example of" the phonolite type, with an alkaline-earth carrier, for example1 limestone or dolomite, if necessary supplemented with' iron ore. By this means, an alumina carrier of moderate cost is obtained.
25 This type of composition, having a high alumina
content and a high alkali content, may be advantageously melted in fired or electric glass furnaces.
Further details and advantageous
30 characteristics will emerge from the description below of non-limiting preferred embodiments.
Table 1 below gives the chemical compositions, in percentages by weight, of five examples.
When the sum of all the contents of all the
35 compounds is slightly less or slightly greater than 100%, it should be understood that the difference from 100% corresponds to the unanalysed minority impurities/components and/or is due merely to the

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accepted approximation in this field in the analytical methods used.
Table 1

EX. 1 EX. 2 EX. 3 EX. 4 EX. 5
SiO2 47.7 42.6 44.4 45.2 45.4
A12O3 18.6 18.1 17.3 17.2 18.1
CaO 6.2 22.7 21.7 15.3 13.5
MgO 7.1 0.2 0.4 0.5 0.5
Na2O 8.0 6.3 6.0 6.2 6.5
K2O 5.2 7.4 7.1 7.8 8.1
Fe2O3 7.2 2.5 3 6.6 7.3
TOTAL 100 99.8 99.9 98.8 99.4
SiO2 + A12O3 66.3 60.7 61.7 62.4 63.5
Na2O + K20 13.2 13.7 13.1 14 14.6
(Na2O + K2O) / AI2O3 0.71 0.76 0.76 0.81 0.81
Tloq 2.5 1293°C 1239°C 1230°C 1248°C 1280°C
Tiiq 1260°C 1200°C 1190°C 1160°C 1160°C
Tloq 2.5 ~ Tiia + 33°C + 39°C + 40°C + 88°C + 120°C
¦!¦ annealinq 622°C 658°C 634°C 631°C
Dissolution rate at pH = 4.5 > 30 ng/cm2 per h > 30 ng/cm2 per h 2 30 ng/cm2 per h 107 ng/cm2 per h 107 ng/cm2 per h
The compositions according to these examples were fiberized by internal centrifuging, especially according to the teaching of the aforementioned Patent
10 WO 93/02977.
The working ranges, defined by the difference Tiog 2.5 ~ Tuq, are largely positive. All have a (Na2O + K2O)/AI2O3 ratio of greater than 0.7 for a high alumina content of approximately 17 to 20%, with quite a high
15 (SiO2 + AI2O3) sum and an alkali content of at least 13.0%.

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Examples of additional compositions according to the invention (referred to as Ex. 6 to Ex. 40) have proved to be beneficial and are given in Table 2.
All have a (Na2O + K2O) /A12O3 ratio of greater 5 than 0.5, especially greater than 0.6, even greater than 0.7.
The alumina content is high, between 17 % and more than 25 %, with a quite high {SiO2 + AI2O3) sum, especially greater than 60 %.
10 The alcali content of the additional
compositions is especially between less than 11.5 % and more than 14 %.
It should be noted that their working ranges are largely positive, especially greater than 50°C, 15 indeed greater than 100°C and even greater than 150°C.
The liquidus temperatures are not very high, especially less than or equal to 1200°C and even 1150°C.
The temperatures (Tlog 2.5) corresponding to viscosities 20 of 102'5 poise are compatible with the use of high-temperature fiberizing dishes, especially under the conditions of use that are described in Application WO 93/02977.
The preferred compositions are especially those 25 in which Tiog 2.5 is less than 1350°C, preferably less than 1300°C.
It has been able to be shown that for
compositions comprising between 0 and 5% magnesia MgO,
especially with at least 0.5% of MgO and/or less than
30 2%, or even less than 1%, of MgO and between 10 and 13%
of alkalis, very satisfactory values of physical
properties, especially working ranges and rate of
dissolution, are obtained (in the case of examples :
Ex. 18, Ex. 31, Ex. 32, Ex. 33 and ex. 35 to Ex. 40).
35 It sould be noted that their Annealing
temperatures are especially greater than 600°C, even greater than 620°C, and even greater than 630°C.

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Table 2

EX. 6 EX. 7 EX. 8 EX. 9 EX. 10 EX. 11 EX. 12 EX. 13 EX. 14 EX. 15
SiO2 43.9 44 .2 43. 8 46.1 43.8 47.1 41.9 48.2 43.2 46. 3
A12O3 17.6 17 .6 17. 6 17.4 17.6 15.7 20.9 19.8 22.5 19. 3
CaO 15 13 .3 14. 2 13.2 11.9 9.8 14.5 14 14.3 13. 9
MgO 0.5 0 .5 0. 5 0.5 0.5 0.4 0.5 0.5 0.5 0. 5
Na2O 6.40 6 .3 6. 4 6.3 6.4 6.4 6.1 6 6 6
K2O 7.6 7 .9 7. 9 7.8 8.0 8.0 7.4 7.2 7.1 7. 1
Fe2O3 8.4 9 .8 9. 2 8.3 11.3 12.1 8.7 4.2 6.3 6. 8
TOTAL 99.4 99 .6 99. 6 99.6 99.5 99.5 100 99.9 99.9 99. 9
SiO2 + A12O3 61.5 61 .8 61. 4 63.5 61.4 62.8 62.8 68 65.7 65. 6
Na2O + K2O 14.2 14 .2 14. 3 14.1 14.4 14.4 13.5 13.2 13.1 13. 1
(Na2O + K2O) /A12O3 0.81 0 .81 0. 81 0.81 0.81 0.92 0.65 0.67 0.58 0. 66
Tloq 2.5+ (in *C) 1270 1285 1275 1310 1295 1305 1300 1380 1345 1335
Tliq (in °C) 1120 1100 1110 1140 1160 1200 1140 1160 1140 1110
Tlog 2.5 ~ Tiiq
(in °C) 150 185 165 170 135 105 160 220 205 225
¦lannealina ' ^-^ °C) 618 615 616 635 654 655 645
Dissolution rate at pH = 4.5 (in ng/cm2 per hour) 45 > 30 > 30 > 30 60 > 30 > 30 > 30 > 30 £ 30

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Table 2 (continuation 1)

EX. 16 EX. 17 EX. 18 EX. 19 EX. 20 EX. 21 EX. 22 EX. 23 EX. 24 EX. 25
SiO2 45.4 43 44.3 43 47.7 45.6 43.5 43.1 40.3 42.3
A12O3 18.8 19.7 19.8 21.5 18.4 22.4 21.2 22.2 25.1 21.7
CaO 13.9 14.1 13.4 14.1 13.8 13.9 14.1 14 13.9 13.1
MgO 0.5 0.5 0.7 0.5 0.5 0.5 0.5 0.5 0.5 0.6
Na2O 5.9 6 8.3 6 6 6 6 6 6 5.9
K20 7.2 7.2 3.7 7.3 7.3 7.3 7.2 7.2 7.2 7.7
Fe2O3 8.3 9.5 9.3 7.5 6.2 4.2 7.4 6.9 6.9 8.7
TOTAL 100 100 99.5 99.8 99.9 99.9 99.9 99.9 99.9 100
SiO2 + AI2O3 64.2 62.7 63.8 64.5 66.1 68 64.7 65.3 65.4 64.0
Na2O + K20 13.1 13.2 12 13.3 13.3 13.3 13.2 13.2 13.2 13.6
(Na2O + K2O) /A12O3 0.7 0.67 0.61 0.62 0.72 0.59 0.62 0.59 0.53 0.63
Tloq 2.5. (in °C) 1315 1305 1250 1325 1345 1370 1325 1335 1330 1300
Tua (in °C) 1110 1110 1170 1140 1150 1150 1120 1160 1170 1160
Tlog 2.5 ~ Tliq
(in °C) 205 195 80 175 195 220 205 175 160 140
¦'¦annealinq (in L.) 637 638 644 645 658 644 650 652
Dissolution rate at pH = 4.5 (in ng/cm2 per hour) > 30 > 30 > 30 > 30 > 30 > 30 > 30 £ 30 > 30 > 30

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Table 2 (continuation 2)

EX. 26 EX. 27 EX. 28 EX. 29 EX. 30 EX. 31 EX. 32 EX. 33 EX. 34
SiO2 43.9 41.5 39.3 47.3 45.3 45.3 44 46.5 46.5
A12O3 24.6 24.7 24.9 18.2 19.2 20.5 22.5 19.2 19.5
CaO 13.2 13.4 13.3 13.9 12.9 12.9 12.7 12.4 11.5
MgO 0.6 0.6 0.5 0.6 0.8 0.8 0.8 0.8 0.7
Na2O 5.9 6.2 6.3 8.1 7.9 8.3 7.9 8.8 8.4
K20 7.6 7.6 7.6 3.9 5.7 3.8 3.7 3.9 5
Fe2O3 4 6 8.1 7.5 7.5 7.4 7.5 7.4 7.5
TOTAL 99.8 100 100 99.5 99.3 99 99.1 99 99.1
SiO2 + A12O3 68.5 66.2 64.2 65.5 64.5 65.8 66.5 65.7 66
Na2O + K20 13.5 12.8 13.9 11.9 13.6 12.1 11.6 12.7 13.4
(Na2O + K2O) /A12O3 0.55 0.52 0.56 0.65 0.7 0.59 0.52 0.66 0.69
Tioq 2.5+ (in °C) 1370 1330 1295 1270 1270 1280 1285 1280 1295
Tnq (in °C) 1180 1200 1160 1150 1180 1200 1150 1170
Tlog 2.5 ~ Tuq
(in °C) 150 95 110 120 100 85 130 125
¦"¦annealinq (in C) 625 618 619
Dissolution rate at pH = 4.5 (in ng/cm2 per hour) > 30 > 30 > 30 > 30 > 30 > 30 > 30 > 30 > 30

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Table 2 (continuation 3)

EX. 35 EX. 36 EX. 37 EX. 38 EX. 39 EX. 40
SiO2 47.7 46.5 48.0 47.1 46 46
Al2O-i 18.9 19.5 19.2 21 20.5 20.1
CaO 13.6 14.4 llJ.b 1 2 . b 11.6 14.4
MgO 1.4 1.4 0.7 0.7 0.7 1.1
Na2O 7.4 7.3 7.4 7.2 7.4 7.1
K20 5 5 5 5 5 5
4.8 4.9 4 .9 4.9 7.3 4.9
TOTAL 98.8 99 98.8 98.5 98.5 98.6
SiO2 + A12O3 66.6 66.0 67.2 68.1 66.5 66.1
Na2O + K2O 12.4 12.3 12.4 12.2 12.4 12.1
(Na2O + K20) /Al2O-i 0.66 0.63 0.65 0.58 0.6 0.6
Tioc 2.5. (in °C) 1310 1295 1315 134 0 1320 1300
TUq (in °C) 1140 1150 1120 1110 1120 1140
Tlog 2.& ~ T|iq
(in °C) 170 145 195 230 200 160
lannealint) (in L J 636 636 64 0 64 3 633 641
Dissolution rate at pH = 4.5 (in ng/cm2 per hour)
-13-WE CLAIEfl:
1. A process for the preparation of mineral wool capable of dissolving in a phy3io(oglcal medium, whfeh mineral wool comprises the constituents beiow in the following percentages by weight:

SiO2 39-55%
Al2Oa 16-27%
CaO 3-35%
MgO 0-15%
Na2O 0-15%
K2O 0-15%
R2O (Na2O+K2O) P2O5 10-17% 0-3%
Fe3O3 0-15%
B2O3 0-8%
TlO2 0-3%


Preferably 40-52%
H ft 16-25%
a a 10-25%
a a 0-10%
U II 6-12%
a a 3-12%
a " 12-17%
a K 0-2%
n a
a a 0-4%

and in that MgC is between 0 and 5%, especially between 0 to 2%, when R2O 2. The process as claimed in claim 1, wherein it comprises the constituents
below In the following percentages by weight:
AbO3 16-25% Preferably 17-22%
K2O 0-15% " 06-12%
R2O 13.0-17%

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3. The process as claimed in claim 1 or 2, characterized in that the
(N92O+K2O) alkali content is between;
13,0 4. The process as claimed In one of the preceding claims, wherein It
comprises FeaO^ (total Iron) contents such that:
0 5. The process as claimed in one of claims 1 to 3, wherein it comprises
Fe^Os (Iota! iron) contents such that;
5 6. The process as claimed in one of the preceding claims, wherein it satisfies
the relationship:
(Na2O +K2O)/AI2O3> 0.5
7. The process as claimed In one of the preceding claims, wherein It satisfies
the relationship
(Na2O +K3O)/AhO3 > 0.6, especially (Na2Q +K2O)/AI2O3 > 0.7
8. The process as claimed In one of the preceding claims, wherein It
comprises lime and magnesia contents such that;
10 and 0
-15-
9. The process as claimed In one of the claims 1 to 7. wherein I! comprises
time and magnesia contents such that
5 10. The process as claimed in claim one of \X\s preceding claims, wherein it
has a rat© of dissolution of at least 30 ng/cmz per hour measured at pH
4.5.
11. The process as claimed in one of the preceding claims, wherein it is
obtained by flberlzlng a glass produced by melting Inexpensive raw
maierfafs, especially rocks, for exampfe phortoMe, and an alkaflne-earth
carrier, for example limestone or dolomite, if necessary supplemented with
iron or®,
12. Trro process as claimed in one of the preceding claims, wherein the
corresponding glass may be fifcerized by internal cenirifuging.
Mineral wool capable of dissolving in a physiological medium, which mineral wool comprises the constituents below in the following percentages by weight:
and in that MgO is between 0 and 5%, especially between 0 to 2%, when R2O

Documents:


Patent Number 201969
Indian Patent Application Number IN/PCT/2000/0043/KOL
PG Journal Number 08/2007
Publication Date 23-Feb-2007
Grant Date 23-Feb-2007
Date of Filing 15-May-2000
Name of Patentee ISOVER SAINT-GOBAIN, "LES MIROIRS"
Applicant Address 18, AVENUE D'ALSACE, F-92400 COURBEVOIE, FRANCE, A FRENCH COMPANY.
Inventors:
# Inventor's Name Inventor's Address
1 BERNARD, JEAN-LUC 51, RUE ANDRE OUDIN GIENCOURT, F-60600 CLERMONT, FRANCE
2 LAFON, FABRICE 34, RUE HERMEL, F-75018 PARIS, FRANCE
3 VIGNESOULT, SERGE 39 RUE BERTHE, F-75018, PARIS, FRANCE
PCT International Classification Number C03C 13/06
PCT International Application Number PCT/FR99/02205
PCT International Filing date 1999-09-16
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 98/11607 1998-09-17 France