CZ200035A3 - Mineral wool - Google Patents

Abstract

Mineral wool exhibiting the ability to dissolve in physiological medium and contains in percentages by weight: SiO2 38 - 52%, A12O316-23%, CaO and / or MgO 4 -15% Na2O and / or K2O 16-25%, B2O3 0-10%. Fe2O3 (total iron) 0-3%, preferably 0-1.5% P2O5 0 - 1.5% and TiO2 0 - 2%.

Description

Technical field

The invention relates to the field of artificial mineral wool production. In particular, the invention relates to mineral wool intended for the preparation of heat and / or sound insulating materials or substrates for pure cultures.

More particularly, the invention relates to mineral wool of the glass wool type.

BACKGROUND OF THE INVENTION

This type of mineral wool is usually spun using so-called internal centrifugal processes, ie processes using high speed centrifugal devices and provided with drilled holes. In fact, these processes are very suitable for spinning mineral wool of the glass wool type, which in a broader perspective has a composition rich in alkali metal oxides and which exhibits lower liquidus temperature and higher viscosity at the spinning temperature than rock wool and basalt wool. This type of process is described in particular in patents EP-0 189 354 and EP-0 519 797.

In addition to the known criteria of industrial and economic feasibility and quality level, the requirement of mineral wool biodegradability, ie the ability to undergo rapid dissolution in physiological medium, has been added in recent years, thus avoiding any potential risk of pathogenic action in relation to possible

Fefefe fefe 9 9 9 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 ··· · · ·· Accumulation of fine fibers in the body due to inhalation.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to find a more advantageous chemical composition of mineral wool, particularly of glass wool, where the improvement is particularly aimed at increasing its biodegradability and / or jointly achieving sufficient biodegradability and spinning capability by internal centrifugation.

The subject of the invention is a mineral wool having the ability to dissolve in a physiological medium comprising the following components, which are expressed in percent by weight:

screen ₂ ^A1 2 ° 3

RO (CaO and / or MgO)

R ₂ 0 (Na ₂ 0 and / or K ₂ 0) ^B 2 ° 3 ^P 2 ° 5 ^Ρβ 2θ3 (total iron)

- 52%, preferably at least 40%, in particular 41% - 48% or 45% - 50%

- 23%, preferably 17% - 21% or 17% - 20%

- 15%, preferably

- 12% or 5% - 11%

16% - 25%, preferably 17% - 22% or 17% - 20%

- 10%, in particular at least 1%, preferably 3% - 9% or 4% - 10%

- 3%, preferably 0% - 1.5%, in particular 0% or more than 0% and at most 0.5%

0% - 3%, preferably 9 i

9 9 9 9 9

9 9 9 9 9 9 9 _ · «···· · · 9 9

9

9 99 9999

0% - 1.5%, especially about 0.01% to 1%

Ti0 ₂ 0-2%.

(Within the remainder of the text, any percentage of the composition component should be understood as a percentage by weight).

The choice of the composition of the composition thus made it possible to achieve a number of advantageous characteristics, in particular by changing the numerous complex functions that many specific components of the composition exhibit.

Accordingly, the present invention provides a glass wool-type mineral wool wherein the content of alkali metal oxides (R ₂ O), essentially represented by the form Na ₂ O and / or K ₂ O, is greater than the content of alkaline earth metal oxides (RO) in the mineral wool , essentially represented by the form of CaO and / or MgO. The iron oxide content (measured in the form of Fe ₂ 0 ₃ , but usually corresponding to the total iron content) is very low or even zero; on the other hand, the boron oxide content is significant.

In addition, the viscosity value of the composition is suitable for carrying out the internal centrifugation process.

As regards the biodegradability of mineral wool, it is known that certain compounds such as P ₂ 0 ₃ may biodegradability significantly improved, particularly in the mineral composition type glass wool, while other oxides such as aluminum oxide, on the contrary tend biodegradability reduced, at least in neutral pH range. In this respect, it is possible to refer for example to Patent EP-412 878. The massive addition of P ₂ 0 ^ (e.g., dropped or

However, within the context of the invention, it has not proved to be the most reasonable approach. In this context, namely arise other problems such as issues of economic (P ₂ ° ₅ is prepared from expensive raw materials) and also also issues technical changes in the proportions Ρ ₂ θ5 ^{'and the} j ^Measured at proportions of aluminum oxide, within a given compositions may cause undesirable or unknown changes in other properties. Thus, phosphorus pentoxide Ρ ₂ θ5 is not unaffected by the viscosity value of the composition, like aluminum oxide. In particular, however, in the case of fiberglass-type compositions which are intended to be spun by an internal centrifugation process, where the method of the invention can be applied particularly advantageously, the viscosimetric behavior of the composition is an important criterion which needs to be adequately controlled.

Accordingly, a reasonable compromise has been established within the process of the invention, essentially as follows: the composition may contain P ₂ O 4 but in a not too large amount of not more than 3% or 1.5%. Thus, the beneficial effect on biodegradability is maintained without excessive addition, which is costly and tends to increase the liquidus temperature of the composition.

Suitably selecting the contents of the other main components of the composition, namely RO, _R2 0, θ3 ® ₂ ^and Si0 _2, on the other hand, the content of A1 ₂ Oj substantially increased and moves at least in the range from 16% to 17%. Accordingly, the aluminum oxide content may preferably be at least 18%, in particular at least 19% or at least 20%.

According to the present invention, it has been found that this combination has sufficiently enabled the achievement of the relevant bio-solubility criteria, both when measuring.

9 9 · 9 9 9 • 9 9 · 9 9 69 99 for in vitro tests in the neutral pH range and for in vitro tests in the acid pH range. In fact, however, the problem of determining the pH that best suits the in vivo environment of a physiological medium, particularly a lung medium, has not yet been solved with certainty. High aluminum oxide content has so far seemed to be beneficial in terms of rapid dissolution in the acidic pH range, but in the neutral pH range it only results in poor / slow dissolution.

The method according to the invention makes it possible to achieve a high level of bio-solubility, at least in vitro measurements at any pH, by selecting a high alumina content, but by adapting the content in particular RO, R2O and ^ 2®3 'to maintain the beneficial effect of aluminum oxide in the acidic pH without negatively affecting neutral pH behavior.

The CaO content of the composition of the invention is preferably selected to be in the range of 4% to 11%.

Similarly, the MgO content of the composition of the invention is preferably selected to be in the range of 0.1% to 7%, particularly in the range of 0.3% to 6.5%.

In fact, it is customary to select a CaO content that is higher than the MgO content for a given total alkaline earth oxide content, mainly due to the cost of the raw materials. Thus, the MgO content may be selected to be very low or even zero (e.g., in the range of 0% to 1%) or higher, and may, for example, be in the range of 2% to 6%.

«« • · »

According to a first embodiment of the invention, the CaO / MgO ratio can thus be = = 1.25, in particular 2 = 5 and even with 10.

However, it has proved beneficial in the context of the invention to provide a second embodiment consisting of adjusting MgO contents that are comparable or even greater than CaO contents. Thus, MgO / CaO ratios may be greater than 0.8 or even greater than or equal to 1 or 1.05: this ratio, which is different according to the corresponding CaO and MgO contents, could have a beneficial effect on the biodegradability of the composition.

The Na 2 O content of the composition is at least 12%, preferably from 13% to 19.5%, while the K ₂ O content is at least 0.5%, preferably from 0, 5% to 8%.

Similarly as in the case of CaO and MgO contents of alkaline earth oxides, the alkali metal oxides the composition usually has a significantly higher content of Na ₂ 0 in comparison with the content of K ₂ 0. For a given total content of alkali metal oxides may therefore be the K ₂ 0 very low or zero (e.g., less than 3%, preferably from 0.5% to 2.5%). However, in the embodiment of the invention it is also possible to select a substantially higher K ₂ O content, for example ranging from about 5% to 7%, which may, for example, be up to more than one quarter or even more than one one-third of the total sum of the alkali metal oxides in the composition.

In a preferred embodiment the composition comprises alkaline earth oxides and alkali oxides in the following ratio: R ₂ 0 / R0> 1.8, in particular between ♦ • • · · ·

• • »» »

9 9 9 9 9 9 99 99 from 2 to 4.

In this context, it is important to emphasize that the sum of SiO 2 + Al ₂ O ₃ allows the viscosimetric behavior of these compositions to be controlled on a large scale: preferably it is at least 60%, in particular in the range of 61% to 67%.

As far as the iron oxide (or oxides) content (total iron) is concerned, this content is optional as mentioned above. The composition may have a low content of iron oxide added intentionally or occurring as an impurity. The presence of iron oxide in this composition can favorably influence the fire resistance of the obtained mineral wool.

As in the case of iron, the presence of P ₂ O 4 in this composition is optional, the content of this oxide being zero or up to 0.1% or at least 0.1% and up to 1.5% or 2%.

In a preferred embodiment, it is also possible to optionally use boron oxide, which acts in particular as a flux, i.e. in a manner similar to that of alkali metal oxides, and the presence of boron oxide appears to be favorable in terms of mineral wool biodegradability. Furthermore, the presence of this oxide tends to improve the thermal insulation characteristics of the mineral wool, in particular by causing the mineral wool to reduce the thermal conductivity coefficient in its radiation component.

The composition may further comprise a plurality of other, less significant, compounds generally having a maximum content of from 2% to 3% of the composition. These compounds may, for example, be trace amounts of TiO ₂ , MnO, SO 3, etc.

The temperature at which these compositions exhibit a viscosity τ (in poise) when logt = 2.5, T _log 25 and / or a temperature at which they exhibit a viscosity τ (in poise) when logt = 3, they are / is greater than the liquidus temperature T ^^ _Q;

difference T _{log2> 5} - T _liq and / or T _log3 - T _LLQ is preferably at least 10 ° C, more preferably at least 20 ° C or 40 ° C. This difference defines the operating range of the compositions of the invention, that is, the temperature range over which these compositions can be spun, particularly by an internal centrifugation process.

Thus, the mineral wool specified above exhibits a sufficient level of bio-solubility, regardless of whether the measurement methods use a neutral or weakly alkaline or acidic pH.

Thus, a mineral wool in an embodiment of the invention generally exhibits a dissolution rate of at least ng / cnr per hour, or at least 40 or 50 ng / cm per hour when measured at pH 4.5, while measured at pH 7.5 the dissolution rate is at least 30 ng / cm per hour, preferably at least 40 or 50 ng / cm per hour.

The mineral wool generally exhibits a dissolution rate of at least 30 ng / cm per hour, preferably at least 40 or 50 ng / cm per hour when measured at pH 4.5, while measured at pH 6.9 dissolution rate

4

9

4444 9

9 * 99 «4 9» »9

9 9 9 9 9 9 9 9 9 4

At least 30 ng / cm ² per hour, preferably at least 40 or 50 ng / cm 2 per hour.

The mineral wool generally also exhibits a dissolution rate of at least 60 ng / cm per hour, preferably at least 80 ng / cm per hour when the measurement is performed at pH 4.5 and / or a dissolution rate of at least 40 ng / cm per hour , preferably at least 60 ng / cm 2 per hour when the measurement is performed at pH 6.9 or at pH 7.5.

This mineral wool is mainly used to prepare heat and / or sound insulating materials or substrates for pure cultures. The invention therefore also relates to any product comprising, at least in part, a mineral wool as defined above.

DETAILED DESCRIPTION OF THE INVENTION

Further details and advantageous characteristics will be explained in more detail below with reference to specific examples, which are illustrative only and do not limit the scope of the invention.

Table 1 lists the chemical compositions for the nine examples in weight percent.

Table 2 gives three other examples where the accuracy of the chemical analyzes was somewhat higher, and also three physical characteristics, namely liquidus temperature (T _liq ), temperature (T _log3 ) at which the viscosity value τ expressed in the description is such, paying LogTech = 3 and the temperature (T ^ 2 _og 5) · P ^{s k_t} ns, τ is the viscosity, expressed in poise is such that LogTech = 2.5, where these

9 9 9

9

9 9

9

9 9 ·· * 9 9 9 9

9 9 9

9

9 ° 99 three temperatures are expressed in ° C.

If the sum of all contents for all compounds is somewhat lower or slightly higher than 100%, it should be taken into account that a deviation of 100% corresponds to irrelevant impurities or components that are not always analyzed or cannot be analyzed in trace amounts (TiO ₂ , S0 ₃ ) and / or arises from approximations recognized in the analytical methods used.

Fe feef fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fefe · fefe fefe · fefe · fe fefe

TABLE 1

Ex.l Ex. 2 Ex. 3 Ex. 4 Ex. 5 SiO ₂ 46.3 41.5 41 46 48.1 ai ₂ o ₃ 19.9 19.6 20.1 18 16.9 CaO 5.1 10.1 7.9 5.8 4 MgO 0.5 0.3 3 6.1 6.1 Na ₂ O 19.4 19.0 13.8 17 13 to ₂ ° 0.5 0.5 7.2 5 6 ^B 3 ° 3 8.3 9 6 1,2 3.5 ^Fe 2 ° 3 - - 0.9 1 1.5 ^P 2 ° 5 - - - - 1 Total 100 ALIGN! 100 ALIGN! 99.9 100.1 100.1 (RO) 5.6 10.4 10.9 11.9 10.1 (R ₂ o) 19.9 24 21 22nd 19 Dec

· 4 · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · • 4 • 9

Table 1 (continued)

Ex.6 Ex. 7 Ex.8 Ex. 9 Si ° ₂ 44.6 46.5 49.94 51.3 ^A1 ° 2 19.5 17.6 17.3 16.5 CaO 8 5.9 5.1 5.2 MgO 2.3 4.4 2.2 3 Na20 13.6 16.7 13.7 12.7 k ₂ o 6.5 5.9 6.6 4.4 ^B 3 ° 3 5 1.6 5.1 3.4 ^Fe 2 ° ₃ 0.6 1.4 0.6 2,0 ^P 2 ° 5 0.0 0.0 0.0 1.6 Total 100.1 100 ALIGN! 100 ALIGN! 100.1 (RO) 10.3 10.3 7.3 8.2 (r ₂ 0) 20.1 22.6 20.3 17.1

9 9 ·· ·· • 99 9900 9 • 999 99 99 9

9999998 9 * * ·

9 9 9 9 9 9 • 9 99999999

TABLE 2

Ex.10 Ex.ll Ex.12 SiO ₂ 46.35 49.3 49.64 ^a1 2 ° 3 19.9 17.3 17.9 CaO 5.1 5.1 7.8 MgO 0.04 2.2 2.7 Na ₂ O 19.4 13.7 16.6 k ₂ o 0.01 6.6 1.15 B ₃ ° 3 8.95 5,05 4.15 ^Fe 2 ° 3 0.02 0.6 0.01 ^P 2 ° 5 0 0.04 0.01 tío ₂ - - 0.02 Sat ₃ - 0.03 0.01 Total 99.77 100 ALIGN! 99.99 (RO) 5.14 7.3 10.5 (r ₂ o) 19.41 20.3 17.75 ^T liq 970 970 1050 ^T log3 1072 1166 1139 ^T log2.5 1183 1274 1242

9 9 99 99 99 9999 9999 999 · 999 ·

9 9 ··· ·· · 9 9 »9 · · 999 9999

9,999,999 9 · 99

These compositions have been subjected to spinning by an internal centrifugation process, in particular in accordance with the data disclosed in the aforementioned patents.

The working ranges, defined by the difference T ^ _Q g ₂ 5 IIQ ^_T »these examples were more than positive.

The biodegradability of these compositions, in particular the biodegradability measured in the neutral or weakly acidic pH range (pH 4.9 or 7.5) or in the acidic pH range (4.5), was sufficient.

Examples 1 and 2 relate to a first embodiment of the invention wherein the strongly predominant alkaline earth metal oxide is CaO and the strongly predominant alkali metal oxide is Na ₂ O.

Examples 3 to 9 relate to a second embodiment of the invention, wherein the MgO content of the alkaline earth metal group and the K ₂ O content of the alkali metal group are not insignificant.

Examples 10-12, whose characteristics are specified more precisely, show that the compositions are characterized by good melting characteristics (T ₁ values _{; i} are not too high) and a working range that is wide enough to allow these compositions to be free of excessive difficulty processed by the spinning process.

Claims (15)

PATENT CLAIMS CLAIMS 1. Mineral wool having the ability to dissolve in a physiological medium, characterized in that it contains the following components, the percentage by weight of which is given; SiO ₂ ^A1 2 ° 3 RO (CaO and / or MgO) R ₂ 0 (Na ₂ 0 and / or K ₂ 0) ^B 2 ° 3 ^Ρβ 2θ3 ( ^ce l iron) ^P 2 ° 5 tío ₂ 38 - 52%, preferably at least 40%, in particular 41% - 48% 16 - 23%, preferably 17% - 21% 4-15%, preferably 5 - 12% 16% - 25%, preferably 17% - 22% 0-10%, in particular at least 1%, preferably 3% -9% 0% - 3%, preferably 0% - 1.5% 0-3%, preferably 0% -1.5% 0-2%. Mineral wool according to claim 1, characterized in that it contains CaO in an amount ranging from 4% to 11%. ·· · · · · · · · · · · · · · · · -1 r ······· - 10 - · »* * * * 10 10 * 10 10 10 10 Mineral wool according to one of the preceding claims, characterized in that it contains MgO in an amount ranging from 0.1% to 7%, preferably from 0.3% to 6.5%. Mineral wool according to one of the preceding claims, characterized in that it satisfies the formula: MgO / CaO with 0.8%, preferably 1 or 1.05. Mineral wool according to one of Claims 1 to 3, characterized in that it satisfies the formula: CaO / MgO and 1.25%, preferably 5 or 10. Mineral wool according to one of the preceding claims, characterized in that it contains at least 12% of Na ₂ O, preferably in the range of 13% to 19.5%. Mineral wool according to one of the preceding claims, characterized in that it contains K ₂ O in an amount of at least 0.5%, preferably between 0.5% and 8%. Mineral wool according to one of the preceding claims, characterized in that it satisfies the formula: R ₂ O / RO > 1.8%, preferably in the range of 2 to 4. Mineral wool according to one of the preceding claims, characterized in that it comprises: SiO ₂ + Al ₂ O ₃ : at least 60%, preferably from 61% to 67%. 417 • · * »» 9 9 1> 9 9 1> 9 9 4> · · < Mineral wool according to one of the preceding claims, characterized in that it has a T _{1 (J} g ₂ 5 and / or a temperature ^T i _og 3 and a liquidus temperature T £ £ _q , wherein the difference (T £ _O g) ₂ 5 - ^T 1 (q 1) or (Ti ₀ g 3 - ^T 1q) is at least 10 ° C, preferably at least 20 ° C, particularly preferably 40 ° C. Mineral wool according to one of the preceding claims, characterized in that it has a dissolution rate of at least 30 ng / cm per hour when the measurement is carried out at pH 4.5 and a dissolution rate of at least 30 ng / cm 2 per hour when measuring at pH 7.5. Mineral wool according to one of the preceding claims, characterized in that it has a dissolution rate Of at least 30 ng / cm 2 per hour when measured at pH 4.5 and a dissolution rate of at least 30 ng / cm 2 per hour when measured at pH 6.9. Mineral wool according to one of the preceding claims, characterized in that it has a dissolution rate of at least 60 ng / cm per hour when the measurement is carried out at pH 4.5 and / or a dissolution rate of at least 40 ng / cm per hour in the case of wherein the measurement is performed at pH 7.5 and / or the dissolution rate is at least 40 ng / cm per hour when the measurement is performed at pH 6.9. Mineral wool according to one of the preceding claims, characterized in that it is obtained by an internal centrifugation process. «4 • 4 • 4 4 • 4 4 4 • 4 4 4 4 4 4 4444444 4 4 4 4 4 4 4 4 4 4 4 44 44 4 4 4 4 4 5 4 4 4 4 4 4 4 4 4 4 5 4 4 4 4 4 4444 44 44 Heat and / or sound insulating products or substrates for pure cultures, characterized in that they comprise, at least in part, the mineral wool according to one of the preceding claims.