SK285275B6 - Mineral wool capable of being dissolved in a physiological medium and thermal and /or acoustic insulation products or substrates for soilless cultures - Google Patents

Abstract

Mineral wool capable of being dissolved in physiological medium comprises the constituents below in the following percentages by weight: 38 to 52 %, preferably 40 to 48 % SiO2, 17 to 23 % Al2O3, 56 to 75 % SiO2 + Al2O3, 9 to 26 %, preferably 12 to 25 % RO oxides (calcium lime and/or magnesium oxide, CaO and/or MgO), 4 to 20 %, preferably 7 to 16 %, MgO, the ratio Mg/CaO is greater or equal 0.8, preferably greater of equal 1.0 or greater or equal 1.15, 3.4 to 18.4 R2O oxides (sodium oxide and potassium oxide, Na2O + K2O), 1.7 % or more, preferably 2 % or more of Fe2O3 (total iron), and satisfies the relationship R2O/Al2O3 is 0.2 to 0.8. The mineral wool advantageously comprises P2O5, B2O3, MnO and TiO2. The solution incorporates also thermal and/or acoustic insulation products or soilless culture substrates comprising the mineral wool.

Description

Technical field

The invention relates to mineral wool with the ability to dissolve in a physiological medium and to heat and / or sound insulating products or substrates for pure cultures. The invention is therefore in the field of artificial mineral wool. In particular, the invention is directed to rock wool or basalt wool mineral wool, i.e. chemical compositions having a high liquidus temperature and high flowability at the spinning temperature.

BACKGROUND OF THE INVENTION

This type of mineral wool is usually spun by so-called "external" centrifugal processes, such as those using a cascade of centrifugal wheels, to which the feed material is fused in a molten state as described in EP-0 465 310 or EP -0,439,385.

On the other hand, the spinning process carried out by the so-called "internal" centrifugal processes, i.e. by high speed centrifugal devices equipped with drilled holes, is normally reserved for spinning a glass wool type mineral wool which has a broader view at the spinning temperature compared to rock. wool or basalt wool composition richer in alkali metal oxides, lower liquidus temperature and higher viscosity. This process is described, for example, in patents EP-0 189 354 or EP-0 519 797.

Recently, however, technical solutions have been developed which allow the adaptation of this internal centrifugal process to the spinning of rock wool or basalt wool, and in particular by modifying the composition of the material constituting the centrifugal devices and further modifying their operating parameters. More detailed information on this matter can be found in particular in the published international patent application WO 93/02977. This adaptation has proven to be extremely beneficial because it makes it possible to combine features that hitherto have not been achieved in either of these two types of wool, rock or glass. Thus, the rock wool obtained by the internal centrifugal process is comparable in quality to that of glass wool at a lower non-fibrous content than the rock wool obtained in the conventional manner. However, this rock wool retains two key aspects related to its chemical properties, namely the low cost of the chemicals used and the highly flame retardant nature.

Thus, there are two possible methods of spinning rock or basalt wool, the choice of one or the other depending on a number of criteria, including the desired level of quality in relation to the intended method of application as well as industrial and economic feasibility.

In addition, the requirement of mineral wool biodegradability, ie the ability to undergo rapid dissolution in physiological medium, has been added to these criteria in recent years, thus avoiding any potential risk of pathogenic action in relation to the possible accumulation of fine fibers in the body due to inhalation.

No prior art document addresses the problem of the chemical composition of rock wool or basalt wool mineral wool in terms of achieving sufficient biodegradability and simultaneous spinning of the product. In other words, finding artificial mineral wool that would meet both of these criteria.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to find a more advantageous chemical composition of glass wool or basalt wool mineral wool, which improvement is particularly aimed at increasing its biodegradability and / or jointly achieving sufficient biodegradability and spinning capability by internal centrifugation (but without excluding other spinning methods).

The nature of the mineral wool having the ability to dissolve in the physiological medium according to the present invention consists in that it contains the following components, the percentage by weight of which:

silica SiO ₂ alumina A1 ₂ O ₃ silica and alumina

SiO ₂ + Al ₂ O ₃ oxides of RO (calcium oxide and / or magnesium oxide CaO and / or MgO) magnesium oxide MgO ratio of magnesium oxide / calcium oxide MgO / CaO oxides R ₂ O (sodium oxide and potassium Na ₂ O + K ₂ O) iron oxide Fe ₂ O ₃ (total iron) satisfying the relation:

ratio of oxides of R ₂ O / Al ₂ O ₃ 0.2 to 0.8.

up to 52%, preferably 40 to 48%, up to 23%, up to 75%, preferably 62 to 72%, up to 26%, preferably 12 to 25%, up to 20%, preferably 7 to 16%, greater than or equal to 0, 8%, preferably greater than or equal to 1.0% or greater, or equal to 1.15%, 3.4% to 18.4%, greater than or equal to 1.7%, preferably greater than or equal to 2%,

Preference is given to mineral wool, which further comprises the following components, the percentage by weight of which is: phosphorus pentoxide P ₂ O ₅ to 5%, boron oxide B ₂ O ₃ to 5%, manganese oxide MnO to 4%, oxide titanium TiO ₂ up to 3%.

Likewise, mineral wool is preferred in which, when the P ₂ O ₅ content is greater than or equal to 0.5% by weight, the Fe ₂ O ₃ (total iron) / P ₂ O ₅ ratio is greater than or equal to 1 and less or equal to 20.

Further, according to the present invention, mineral wool is preferred in which the content of oxides R ₂ O is greater than 5% by weight, preferably 5 to 12% by weight.

Furthermore, according to the present invention, mineral wool is preferred, for which the relation:

the MgO / CaO ratio is 1 to 3.

Preference is also given to mineral wool which contains P ₂ O ₅ in an amount of at least 0.5% by weight or at least 1% by weight, preferably in the range of from 1.5% to 4% by weight.

Also preferred according to the present invention is a mineral wool which contains MgO in the following percentage by weight:

a MgO content of less than or equal to 20%, preferably greater than or equal to 7%, in particular in the range of 7% to 14%.

Further preferred according to the present invention is a mineral wool comprising CaO in the following amount expressed as a percentage by weight: a CaO content of less than or equal to 15%, preferably greater than or equal to 2%, in particular in the range of 5% to 14%.

According to the invention, a mineral wool containing Fe ₂ O ₃ (total iron) in an amount of at least 4% by weight, at least 5% by weight is preferred, preferably in the range of 5% to 9% by weight.

According to the invention, mineral wool comprising SiO ₂ , Al ₂ O ₃ and P ₂ O ₅ in proportions such that, when expressed as a percentage by mass, the sum of:

SiO ₂ + Al ₂ O ₃ + P ₂ O ₅ : at least 60%, in particular 60% to 70%.

Further preferred according to the invention is a mineral wool comprising alumina Al ₂ O ₃ in the following amount expressed as a percentage by weight:

an Al ₂ O ₃ content of greater than or equal to 18%, in particular greater than or equal to 19% or 20%.

The mineral wool of the present invention preferably has a dissolution rate of at least 30 ng / cm ² per hour when the measurement is made at pH 4.5 and a dissolution rate of at least 30 ng / cm ² per hour when the measurement is made at pH 7 , fifth According to an even more preferred embodiment of the invention, the mineral wool has a dissolution rate of at least 30 ng / cm ² per hour when the measurement is performed at pH 4.5 and a dissolution rate of at least 30 ng / cm ² per hour when the measurement is performed at pH 6.9. Most preferably, the mineral wool of the present invention has a dissolution rate of at least 60 ng / cm ² per hour when the measurement is performed at pH 4.5 and / or a dissolution rate of at least 40 ng / cm ² per hour when the measurement is performed at pH 7.5 and / or the dissolution rate is at least 40 ng / cm ² per hour when the measurement is performed at pH 6.9.

This mineral wool is preferably obtained by an internal centrifugation process.

Also included within the scope of the present invention are heat and / or sound insulating products or substrates for pure crops which comprise, at least in part, the mineral wool of the present invention.

In the description of the present invention, all percentages of the component of the composition are to be understood as percentages by weight, and the compositions of the invention may contain up to 2% or 3% of compounds representing non-analyzed impurities, as is customary for compositions of this type.

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

Accordingly, the present invention is a rock wool type rock wool in which the content of alkali metal oxides (R ₂ O), essentially represented by the form of Na ₂ O and / or K ₂ O, is small and substantially not more than 12%, preferably 10% or even 8%. In contrast, the content of alkaline earth metal (RO) oxides in this mineral wool, in the base represented by the form of CaO and / or MgO, is relatively high and is at least 9%, preferably at least 12% or even at least 16%. The iron oxide content (measured in the form of Fe ₂ O ₃ , but usually corresponding to the total iron content) is at a relatively significant level of at least 1.7%, or even at least 5%. This content present in the composition is particularly justified if the composition is to be spun by an internal centrifugation process, since it has been observed that in this case it is possible to slow down the corrosion rate of the materials from which the centrifuge device is assembled. MnO can then perform a similar function and for this reason the composition may optionally also contain a few percent MnO.

In addition, the spinning viscosity of the composition may be sufficiently high to carry out the internal centrifugation process, and the composition may be referred to as a "solid" composition, mainly due to the appropriate content of silicon oxide and aluminum oxide.

As far as the biodegradability of mineral wool is concerned, it is a known fact, especially in rock wool compositions, that certain compounds, such as P ₂ O ₅ , can significantly improve biodegradability, while other oxides tend to reduce biodegradability, at least in the neutral pH range. . In this regard, reference may be made, for example, to patents EP-0 459 897 and WO 93/22251. Massive addition of P ₂ O _5, but within the context of the present invention showed to be most sensible approach. In this context, other issues may arise, such as economic issues (P ₂ O ₅ is prepared from expensive raw materials), as well as technical issues, as changes in P ₂ O ₅ , and in particular aluminum oxide, the compositions may cause an undesirable or previously unknown change in other properties. Thus, P ₂ O ₅ is not affected by the viscosity value of the composition, like aluminum oxide. In particular, in the case of rock wool compositions which are intended to be spinning by an internal spin process where the method of the invention can be applied particularly advantageously, the viscosimetric behavior of the composition is a very critical and important criterion which needs to be adequately controlled and controlled.

In addition, certain types of compounds may be beneficial in terms of certain properties, but at the same time may have an undesirable effect in obtaining a high degree of biodegradability, such as in the case of iron which, as mentioned, is beneficial in extending the lifetime of a centrifuge. at the same time, it could limit the rock wool biodegradability or, in the case of aluminum oxide, which is beneficial in controlling the viscosity of the composition, but may not be very favorable with respect to bio-solubility, especially when measured in in vitro tests conducted in the neutral pH range.

Thus, within the scope of the present invention, a reasonable compromise has been established between all these data, essentially as follows: the composition may comprise P ₂ O ₅ , but in a not too large amount not exceeding 5%, preferably not exceeding 4%. This composition also contains iron oxide, the presence of which is beneficial, but for reasons other than biodegradability. However, the composition can achieve a high level of biodegradability without the addition of excess P ₂ O ₅ (or any other very special compounds considered to be beneficial in terms of biodegradability) by other methods which essentially consist in changing the relative proportion of MgO relative to CaO. In fact, rock-wool compositions generally contain a proportion of calcium oxide CaO that is greater than the proportion of magnesium oxide

MgO. By reversing this ratio, it has been found that it is possible to achieve a high level of biodegradability, which until now has been achieved only with high P ₂ O ₅ contents in order to "compensate" the high levels of aluminum and iron oxide. An additional, and not insignificant, benefit of the low P ₂ O ₅ content is that too high a P ₂ O ₃ content leads to an increase in the liquidus temperature of the composition, which is clearly undesirable for spinning by internal centrifugation.

Another characteristic aspect of the process according to the invention relates to the combination of this specific MgO / CaO ratio with a significantly higher aluminum oxide content, since this aluminum oxide content is at least 17%. It has been found that the combination has sufficiently provided the appropriate bio-solubility criteria both in the in vitro neutral pH and in the acidic pH in vitro assays. In fact, however, the problem of determining the pH that best suits the in vivo environment of a physiological medium, in particular a lung medium, has not been solved to date with certainty. The 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 only results in poor / slow dissolution.

The mineral wool composition according to the invention makes it possible to achieve a high level of bio-solubility, at least when measured in vitro at any pH, by selecting a high alumina content, but by adapting the alkaline earth metal oxide content to maintain the beneficial effect of aluminum oxide in the acidic pH range without behavior in the neutral pH range.

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 largely controlled.

In the present invention, the mineral wool composition fulfills the following relationship:

R ₂ O / Al ₂ O ₃ ranges from 0.2 to 0.8.

The content of alkali metal oxides, i.e. essentially Na ₂ O and / or K ₂ O, is preferably at least 5%, with about 12% (or possibly about 13%) being maintained in a conventional preferred embodiment.

With respect to the iron oxide (s) (total iron) content, as mentioned above, this content is at least 4%, preferably at least 5%, of iron oxides in order to protect the centrifuge devices, and in a particularly preferred embodiment ranging from 5% to 9%. Furthermore, these iron oxides can favorably influence the fire resistance of the obtained mineral wool.

The compositions in an embodiment of the invention also satisfy the following relationship expressed as weight percent: MgO / CaO ranges from 1 to

3. The aforementioned beneficial effect can thus be obtained without too much excess of MgO in relation to CaO causing unnecessary complications or making the purchase of these oxides as raw materials too expensive.

In an embodiment of the invention, the compositions have a P ₂ O ₅ content of at least 0.5% or at least 1%, preferably at least about 1.5% to 4%. This not too high content then in a very favorable manner influences the biodegradability without excessive deterioration of the economic indicators of the composition and also without significant influence on the respective liquidus temperature.

In another embodiment, the invention may be the content of P ₂ O ₅ less and can range from 0% higher, for example from 0.1% to 0.5% and from 0.1% to 1%.

The CaO content in the composition of the invention is less than or equal to 15%, preferably at least 2%, while in a particularly preferred embodiment it is in the range of 5% to 14%.

Similarly, the MgO content of the composition of the invention is less than or equal to 20%, preferably at least 7%, while in a particularly preferred embodiment it is in the range of 5% to 14%.

In principle, it should be taken into account that, apart from the optional P ₂ O ₅ content, the two compounds which have the greatest effect on the spinning viscosity of the composition are silicon oxide and aluminum oxide. Thus, it is possible to select a content of at least 60% (SiO ₂ + Al ₂ O ₃ + P ₂ O ₅ ) in order to guarantee a viscosity value that is sufficiently high for spinning by an internal centrifugation process, preferably in the range of from 60% to 70%, in a particularly preferred embodiment ranging from 61% to 62%.

For example, the oxidation of this composition can be controlled by the addition of MnO.

By adding boron oxide, which can optionally be carried out, the thermal insulation characteristics of the mineral wool can be improved, and in particular there may be a tendency to decrease the thermal conductivity coefficient in its radiation component. The composition may optionally also contain TiO ₂ as an impurity or in the form of a targeted addition (a deliberately added component), for example up to 2%.

Within the range of the mineral wool composition of the present invention, but not limited thereto, the aluminum oxide content of these compositions is at least 18%, preferably at least 19% or at least 20%.

Difference _{og2 5} -T | _iq is preferably at least 10 ° C, particularly preferably at least 20 ° C or 30 ° C: this difference defines the "working range" of the compositions of the invention, i.e. the temperature range over which these compositions can be spun, especially by an internal process spin. The temperature at which these compositions have a viscosity τ (in the description) when log τ = 2.5 is referred to as T | _Og25 , while the temperature disposes of referred to as T _liq .

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

Thus, the mineral wool in an embodiment of the invention generally has a dissolution rate of at least 30 ng / cm ² per hour, preferably at least 40 or at least 50 ng / cm ² per hour when the measurement is made at pH 4.5 while at the measurement performed at pH 7.5 is a dissolution rate of at least 30 ng / cm ² per hour, preferably at least 40 or 50 ng / cm ² per hour.

The mineral wool generally has a dissolution rate of at least 30 ng / cm ² per hour, preferably at least 40 or at least 50 ng / cm ² per hour when the measurement is made at pH 4.5, while the measurement is made at pH 6.9 the dissolution rate is at least 30 ng / cm ² per hour, preferably at least 40 or at least 50 ng / cm ² per hour.

This mineral wool generally also has a dissolution rate of at least 60 ng / cm ² per hour, preferably at least 80 ng / cm ² per hour when the measurement is performed at pH 4.5 and / or a dissolution rate of at least 40 ng / cm ² per hour, preferably at least 60 ng / cm ² per hour when measured at pH 6.9 and / or a dissolution rate of at least ng / cm ² per hour, preferably at least 60 ng / cm ² per hour hour when the measurement is performed 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 containing, at least in part, a defined mineral wool.

DETAILED DESCRIPTION OF THE INVENTION

Further details and advantageous characteristics will be further elucidated by means of specific examples, which are illustrative only and do not limit the scope of the invention.

Table 1 lists the chemical compositions by weight for seven examples.

If the sum of all contents for all compounds is slightly lower or slightly higher than 100%, it should be taken into account that a deviation of 100% corresponds to minor impurities or non-analyzed compounds and / or arises from approximations recognized in the analytical methods used.

Table 1

Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Ex. 6 Ex. 7 SiO ₂ 42.7 45.8 42.1 44.9 42.4 48.0 42.7 A1 ₂ O ₃ 0.0 20.3 18.1 20.7 23.8 19.0 20.0 Fe ₂ O ₃ 7.5 7.5 7.6 7.7 7.0 7.0 7.5 CaO 10.0 10.5 6.1 5.5 5.0 6.0 10.0 MgO 12.5 11.8 13.7 11.4 7.0 7.0 12.5 Na ₂ O 5.0 5 11.3 7.1 8.0 8.0 5.0 K ₂ O 0.5 0.5 0.6 0.9 5.0 5.0 0.5 B ₂ O ₃ 0 0 0 0 0 0 0 P ₂ O ₅ 0 0 0.02 0.04 0 0 0.6 TiO ₂ 1.8 0 0.6 1.9 1.8 - 1.2 MnO 0 0 0.02 0.04 0 - 0 Pretty 100 100 100.1 100.1 100 100 100 CaO + MgO 22.5 22.3 19.8 16.9 12.0 13.0 22.5 Ka ₂ O + K ₂ O (R ₂ O) 5.5 5.5 11.9 8 13.0 13.0 5.5 S1O ₂ + Α1 ₂ Ο ₃ + ₂ 2θ5 63 66.1 60.2 65.6 66.2 67.0 63.6 MgO / CaO 1.25 1.12 2.25 2.04 1.40 1.17 1.25 R ₂ O / A1 ₂ O ₃ 4.09 4.05 1.66 2.11 0.92 1 4.09

The compositions formed according to these examples were subjected to spinning by internal centrifugation processes, in particular in accordance with the data disclosed in said WO 93/02977.

The working ranges, defined by the difference T _{log 21} - T 1 j _q , were more than positive in these examples.

All of the compositions had a ratio MgO / CaO is greater than 1, and not too large (less than 1%) the content of P ₂ O ₅ and the iron oxide content of about 7% or which has been shown to be advantageous in reducing corrosion of the centrifugal plate. These compositions also had a high aluminum oxide content ranging from approximately 18% to 20% with a relatively high amount (SiO ₂ + Al ₂ O ₃ ) and an alkali metal oxide content of at least 5%.

The biodegradability of these compositions, particularly 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 high.

The composition of Example 7, which contained more than 0.5% P ₂ O ₅ , complied with the requirement for a ratio of Fe ₂ O ₃ / P ₂ O ₅ ranging from 1 to 20, as this value was 12.5, which was in accordance with a preferred embodiment of the invention.

Claims (16)

PATENT 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: silica SiO ₂ 38 to 52%, preferably 40 to 48%, alumina Al ₂ O ₃ 17 to 23%, silica and alumina SiO ₂ + Al ₂ O ₃ oxides RO (calcium oxide and / or magnesium oxide CaO and / or MgO) MgO MgO ratio of magnesium oxide / calcium oxide MgO / CaO oxides R ₂ O (sodium oxide and potassium Na ₂ O + K ₂ O) iron oxide Fe ₂ O ₃ (total iron) satisfying the relation: ratio content of oxides of R ₂ O / Al ₂ O ₃ 56 to 75%, preferably 62 to 72%, 9 to 26%, preferably 12 to 25%, 4 to 20%, preferably 7 to 16%, greater than or equal to 0.8, preferably greater than or equal to 1.0, or greater than or equal to 1.15, 3.4% to 18.4%, greater than or equal to 1.7%, preferably greater than or equal to 2%, 0.2 to 0.8. Mineral wool according to claim 1, characterized in that it further comprises the following components, the percentage of which is indicated by weight: P ₂ O ₅ to 5%, boron oxide B ₂ O ₃ to 5%, manganese oxide MnO to 4%, titanium dioxide TiO ₂ to 3%. Mineral wool according to claim 2, characterized in that if the P ₂ O ₅ content is greater than or equal to 0.5% by weight, the Fe ₂ O ₃ (total iron) / P ₂ O ₅ ratio is greater than or equal to 1 and less than or equal to 20. Mineral wool according to one of the preceding claims, characterized in that the content of oxides R 10 is greater than 5% by weight, preferably 5 to 12% by weight. Mineral wool according to any one of the preceding claims, characterized in that it satisfies the relation: the MgO / CaO ratio is 1 to 3. Mineral wool according to one of the preceding claims, characterized in that it contains P ₂ O ₅ in an amount of at least 0.5% by weight or at least 1% by weight, preferably in the range of 1, % 5 to 4 wt. Mineral wool according to any one of the preceding claims, characterized in that it contains magnesium oxide MgO in the following amount expressed as a percentage by weight: a MgO content of less than or equal to 20%, preferably greater than or equal to 7%, in particular in the range of 7% to 14%. Mineral wool according to any one of the preceding claims, characterized in that it contains CaO in the following amount expressed as a percentage by weight: a CaO content of less than or equal to 15%, preferably greater than or equal to 2%, in particular in the range from 5% to 14%. Mineral wool according to any one of the preceding claims, characterized in that it contains Fe ₂ O ₃ (total iron) in an amount of at least 4% by weight, in particular at least 5% by weight, preferably in the range of % from 5 to 9 wt. Mineral wool according to any one of the preceding claims, characterized in that it contains silica SiO ₂ , alumina Al ₂ O ₃ and phosphorus p ₂ O ₅ in proportions such that, when expressed as a percentage by mass, the sum of: SiO ₂ + Al ₂ O ₃ + P ₂ O ₅ : at least 60%, in particular 60% to 70%. Mineral wool according to any one of the preceding claims, characterized in that it contains alumina Al ₂ O ₃ in the following amounts expressed as a percentage by weight: an Al ₂ O ₃ content of greater than or equal to 18%, in particular greater than or equal to 19% or 20%. Mineral wool according to any one of the preceding claims, characterized in that it has a dissolution rate of at least 30 ng / cm ² per hour when the measurement is performed at pH 4.5 and a dissolution rate of at least 30 ng / cm ² per hour at when the measurement is performed at pH 7.5. Mineral wool according to any one of the preceding claims, characterized in that it has a dissolution rate of at least 30 ng / cm ² per hour when the measurement is performed at pH 4.5 and a dissolution rate of at least 30 ng / cm ² per hour at when the measurement is performed at pH 6.9. The mineral wool as claimed in any one of the preceding claims, characterized in that it has a dissolution rate of at least 60 ng / cm ² per hour when the measurement is performed at pH 4.5 and / or the dissolution rate is at least 40 ng / cm ² per hour when measured at pH 7.5 and / or the dissolution rate is at least 40 ng / cm ² per hour when measured at pH 6.9. Mineral wool according to any one of the preceding claims, characterized in that it is obtained by an internal centrifugation process. Thermal or acoustic insulating products or substrates for pure crops, characterized in that they comprise, at least in part, mineral wool according to one of the preceding claims.