SK4896A3 - Mineral fibre composition - Google Patents

Abstract

The mineral fiber that is biodegradable contains 40 to 67 wt. silica, 20 to 45 % wt. % calcium oxide, up to 12 wt. magnesium oxide, % to 10 wt. sodium oxide, up to 15% weight. % boron oxide, up to 25 wt. sodium oxide a % boron oxide, up to 5 wt. phosphorus pentoxide, up to 3 % wt. % alumina and up to 5 wt. titanium dioxide, iron oxide, barium oxide, magnesium oxide and potassium oxide.

Description

The invention relates to a mineral fiber composition which is biodegradable.

BACKGROUND OF THE INVENTION

According to the prior art, the compositions of some mineral fibers which are said to be biodegradable are disclosed.

The biodegradability of mineral fiber materials is of great importance, as various studies have suggested that mineral fibers with very small diameters in the region of less than 3 micrometers are considered to be carcinogenic, whereas biodegradable mineral fibers of the same size do not show any carcinogenicity.

Biodegradability is essential, but the mechanical and thermal properties of mineral fibers or products thereof as well as the processability of mineral fiber materials are also important. For example, mineral fibers are widely used for insulation purposes. Particularly in industrial applications, suitable thermal stability of the mineral fiber is necessary.

The composition must also allow the production of small diameter mineral fibers by known methods, for example by spinning with a nozzle.

SUMMARY OF THE INVENTION

The invention relates to the problem of a new mineral fiber composition which is biodegradable, has good thermal stability and is easy to manufacture.

The invention is based on the finding that the problem is solved by a mineral fiber composition which essentially consists of silica and caustic oxides and which also contains boron oxide or barium oxide.

This composition has been shown to meet the requirement of combining the necessary properties of the mineral fiber, in particular biodegradability, thermal stability and good processability.

of the present invention is. the mineral composition is biodegradable, characterized by the constituents and their content by weight

The subject of the fiber, which is the following percentages:

Si0 ₂ 40 until 67 CaO 20 until 45 MgO 0 until 12 At ₂ 0 0 until 10 ^B 3 ° 3 0 until 15 Na ₂ 0 + Β ₂ 0β 0 until 25 ^P 2 ° 5 0 in until 5 ^^ 2θ3 0 in until 3 TiO 2, Fe ₂ Og, BaO, MnO, K ₂ O 0 until 5

The compositions of the mineral fiber compositions of the present invention allow for jet spinning or centrifugal spinning. The fibers obtained have good temperature stability. Surprisingly, the mineral fibers of said composition exhibit biodegradability. The average fiber diameter is preferably 10 microns or less, particularly preferably between 2.5 to 5 microns.

The addition of boron oxide causes a decrease in the melting point and prevents the formation of microcrystals, resulting in easier control of fiber production.

of the invention have the mineral fiber compositions of this invention

much further said composition (in weight percentage): sieve ₂ 45 to 67 CaO 20 to 45 MgO 0 to 12 At ₂ 0 0 to 10 ^B 3 ° 3 0.5 to 15 Na ₂ 0 + ^B 3 ° 3 1 to 15

Ρ ₂ 0 ₅ Ο to 5

Α1 ₂ Ο ₃ 0 to 3

TiO ₂ , Fe ₂ O ₃ , BaO, MnO, K ₂ 0 0 to 5

The silica content is preferably in the range of 53 to 58% (w / w).

The boron trioxide content is preferably in the range of 3 to 8% (w / w), of which the 4 to 6% range is particularly preferred.

In a preferred embodiment, the alumina content may be from 1 to 3% by weight, preferably 2 to 3% by weight. However, in another preferred embodiment, the alumina content may be less than 1% by weight.

Another preferred mineral fiber composition has the following components and their content (by weight):

A 2 ° 50 in until 60 CaO 25 until 35 MgO 1 until 10 At ₂ 0 1 until 8 ^p 2 ° 5 0 until 3 Α ^ -2θ3 0 in until 2 BaO 0.5 ! until ; 5

The standard powder test of the German Glass Society was used to determine biodegradability. It is an easily executable method and provides satisfactory biodegradability values. The assay method is described in L. Springer, Laboratoriumsbuch für die Glasindustrie, 3rd edition, 1950, Halle / S: V. Knapp Verlag.

The thermal properties of the mineral fibers were determined by the Swedish method. In this method of determination, a horizontal silicon tube furnace, open at both ends, is used having a furnace tube 350 mm long and an inner diameter of 27 mm. In the center of the furnace is a small ceramic pad (30 x 20 x 3 mm), which serves as a holder of the test sample. The test sample has dimensions of 12 x 12 x 12 mm or 0 12 mm x 12 mm and height. The density is normally 100 kg. m. The temperature increase is 5 K min ^- ^. The variation in the height of the test sample is continuously monitored by means of a scanning optic.

The invention will now be described in more detail by way of examples.

BRIEF DESCRIPTION OF THE DRAWINGS

The enclosed Figure shows the dependence of the mineral fibers in% by heating to a temperature ^much C. Examples shrinking Example 1 Made mineral wool composition (weight percent): Si ° ₂ 50 ^Α ^ 2θ3 0.8 Fe ₂ ° 3 0.3 CaO 41.1 MgO 0.6 At ₂ 0 0.4 k ₂ o 0.1 ^Β 2θ3 5.2 This composition allow good processing on the fibers with mean diameter 2.7 microns spinning nozzle at

fiber drawing temperature 1360 ° C.

investigation fibers process by German glassmaking company provided the result 35 mg. kg ^-1 , that is value

high biodegradability.

Determination of the temperature properties by the Swedish procedure gave a value of temperature stability (up to 5% of the change in height) up to 740 ° C, which is quite clearly evident from the relevant record shown as an example in the attached figure.

Example 2

Mineral wool was produced with the following composition (weight percent):

screen ₂ ^A1 2 ° 3 ^Fe 2®3

CaO

MgO

Na ₂ O

56.5

0.3

0.3

29.1

7.8

0.5

5.0

The composition of this composition was well processed into fibers with an average diameter of 2.8 microns by spinning through a nozzle at a spinning temperature of 1320 ° C.

The powder test evaluation according to the German Glass Society's standard procedure gave a result of 39 mg.kg -1, a value of high biodegradability.

Determination of the temperature stability by the Swedish method gave a result of the temperature stability of a 5% reduction in height up to 720 ° C.

Example 3

Mineral (weight percent) produced:

SiO ₂ ^Al 2 ° 3 ^Fe 2 ° 3

CaO

MgO

At ₂ 0 to ₂ o wool with the following composition

51.5

0.3

0.3

6.4

0.5

0.5

The composition of this composition was also well processed into fibers with an average diameter of 2.9 microns by spinning through a nozzle at a spinning temperature of 1340 C.

The powder test evaluation according to the German Glass Society's standard procedure gave a result of 33 mg.kg ^-1 , a value of high biodegradability.

Swedish way-reduced height

Determination of thermal stability gave a thermal stability result of 5 to 700 ° C.

Example 4

Mineral wool was produced with (in weight percent):

SiO ₂ ^A1 2 ° 3 ° 3 ^Fe 2

CaO

MgO

At ₂ 0

K ₂ 0 with the following composition

51.2 1.9 0.5

26.8

9.3

7.3 0,5

1.4

The composition of this composition was well processed into fibers with an average diameter of 2.5 microns by spinning through a nozzle at a spinning temperature of 1340 ^e C.

The powder test evaluation according to the German Glass Society's standard procedure gave a result of 37 mg.kg1, a value of high biodegradability.

Determination of the temperature stability by the Swedish method gave a result of the temperature stability of a 5% reduction in height up to 700 ° C.

Example 5

Mineral wool was produced with the following composition (weight percent):

Si ° ₂ 56 ^a1 2 ° 3 0.3 ^Fe 2 ° 3 0.3 CaO 27.4 MgO 7

Na ₂ 0 4.5 K ₂ 0 Ο, 5 Na ₂ 0 + Κ ₂ 0 5.0 BaO 4

The composition of this composition was well processed into fibers with an average diameter of 2.7 microns by spinning at a spinning temperature of 1360 C.

The powder test evaluation according to the German glass company standard procedure gave a result of 35 mg.kg ^{- 1} , a value of high biodegradability.

Determination of the temperature stability by the Swedish method gave a result of the temperature stability of a 5% reduction in height up to 740 ° C.

Example 6

Mineral wool was produced with the following composition (weight percent):

Si0 ₂ 55.5 Α1 ₂ 0β 0.5 Ρε ₂ Οβ 0.4 CaO 27.1 MgO 7.5 Na ₂ 0 5.5 K ₂ 0 0.5 Na ₂ 0 + K ₂ 0 6.0 BaO 3

The composition of this composition was well processed into fibers with an average diameter of 2.8 microns by spinning at a spinning temperature of 1360 ° C.

The powder test evaluation according to the German Glass Society's standard procedure gave a result of 39 mg.kg ^-1 , a value of high biodegradability.

Determination of the temperature stability by the Swedish method gave a result of the temperature stability of a 5% reduction in height up to 720 ° C.

Example 7

Mineral (weight percent) produced;

Si ° ₂ and i ₂ o ₃

CaO

MgO

At ₂ 0

BaO wave with the following composition

28.5

2.5

The composition of this composition was well processed into fibers with a mean diameter of 2.7 microns by spinning through a nozzle at a spinning temperature of 1350 ° C.

The powder test evaluation according to the German Glass Society's standard procedure gave a result of 35 mg.kg ^- 1, a value of high biodegradability.

Determination of the temperature stability by the Swedish method gave a result of the temperature stability of a 5% reduction in height up to 720 ° C.

Example 8

Mineral (weight percent) produced:

SiO ₂

Α1-2θ3

CaO

MgO

At ₂ 0

BaO wave with the following composition

The composition of this composition was well processed into fibers with an average diameter of 2.8 microns by spinning at a spinning temperature of 1360 ° C.

The powder test evaluation according to the German Glass Society's standard procedure gave a result of 39 mg.kg ^-1 , a value of high biodegradability.

Determination of the temperature stability by the Swedish method yielded a temperature stability result of a 5% reduction in height up to 740 ° C.

Claims (7)

1. Mineral fiber composition, degradable, characterized by the following components (percentage by weight): SiO ₂ CaO MgO For ₂ 0 ^Β 2θ3 Na ₂ 0 t ® 2θ3 ^P 2 ° 5 Α1-2θ3 TiO ₂ , Fe ₂ Og, BaO, MnO, K ₂ O which is biologically t ý m. live 40 until 67 20 until 45 0 until 12 0 until 10 0 until 15 0 until 25 0 until 5 0 until 3 0 until 5 A mineral fiber composition according to claim 1, characterized in that it comprises the components (weight percent): Si ° ₂ 40 in until 67 CaO 20 until 45 MgO 0 until 12 At ₂ 0 0 until 10 • ^Β 2θ3 0.5 until 15 ^ει ^ Ο 4 “ 1 until 15 - ^P 2 ° 5 0 until 5 Α ^ 2θ3 0 until 3 TiO ₂ , Fe ₂ O-J, BaO, MnO, K ₂ O 0 until 5 Mineral fiber composition according to claim 1, characterized in that it contains the components (weight percent): sieve ₂ 45 until 60 CaO 25 until 45 MgO 5 until 10 At ₂ 0 0 until 5 ^Β 2θ3 1 in until 15 Na ₂ 0 + B ₂ Oj 3 until 10 Ρ ₂ 0 ₅ Ο to 1 Α1 ₂ Ο ₃ 0 to 3 TiO ₂ , Fe ₂ O ₃ , BaO, MnO, K ₂ 0 0 to 3 Fe ₂ O ₃ less than 1 Mineral fiber composition according to any one of claims 1 to 3, characterized in that the silica content is 53 to 58% by weight. The mineral fiber composition according to any one of claims 1 to 3, characterized in that the boron oxide content is 3 to 8% by weight, preferably 4 to 6% by weight. Mineral fiber composition according to claim 1, characterized in that it contains the components (weight percent): Si0 ₂ 50 until 60 CaO 25 in until 35 MgO 1 in until 10 At ₂ 0 1 until 8 ^P 2 ° 5 0 in until 3 ai ₂ o ₃ 0 until 2 BaO 0.5 to 5 Mineral fiber composition according to claim 6, characterized in that it contains the components (weight percent): sieve ₂ 52 until 58 CaO 28 until 32 MgO 5 until 10 At ₂ 0 3 until 7 ^P 2 ° 5 0 until 1 A1 ₂ O ₃ 0.5 in until 1 BaO 0.5 until 3