Mineral fiber composition

Compositions: ceramic – Ceramic compositions – Glass compositions – compositions containing glass other than...

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C501S035000, C501S063000, C501S070000, C501S072000

Reexamination Certificate

active

06358872

ABSTRACT:

BACKGROUND OF THE INVENTION
Mineral fibers made by melting and spinning of mineral raw materials, such as rock, slag and the like, are to a great extent used for the manufacture of mineral fiber mats and blankets, primarily for heat and sound insulation purposes within the construction industry. In addition to the formed mat exhibiting good insulation characteristics with respect to heat and sound, increasingly more importance has been recently attached to the characteristics of the mat from the viewpoint of health, primarily of industrial hygiene. This has lead to attention being directed increasingly more to developing fiber which are soluble in biological fluids in order to ensure that fiber particles, which are not transported out of the body, dissolve in the body fluid.
Thus e.g. the patent application WO 89/12032 describes a fiber composition which exhibits an increased solubility in physiological saline solutions. According to the specification, the components in the said compositions may vary within wide limits, but according to the specification, an increase in the amount of amphoteric oxides, i.e. of aluminium, zirconium and titanium, tends to increase the stability of the compositions against extraction. Even though the application does not at all discuss the effects of the presence of phosphorus, there is included an example of a composition containing a little over 6% by weight of P
2
O
5
, in combination with a low content of Al
2
O
3
. This composition exhibits a fairly good solubility, primarily due to the small amount of Al
2
O
3
present.
According to the present invention it has now been discovered that compositions which contain aluminium and/or iron oxides, as well as phosphorus oxide, and wherein the weight ratio of phosphorus to the sum of aluminium and iron, all calculated as their oxides, lies within a fairly narrow range, surprisingly exhibit very favourable solubility characteristics in physiological saline solutions.
The object of the present invention is thus a mineral fiber composition which is soluble in biological fluids and which is characterized in that it contains substantially
45-65% by weight of SiO
2
15-40% by weight of CaO
0-20% by weight of MgO
0-6% by weight of Na
2
O+K
2
O
and in addition aluminium and/or iron oxides as well as phosphorus oxide in such amounts that the weight ratio of P
2
O
5
to the sum of Al
2
O
3
and iron oxide is circa 0.4 to 6.
The total amount of Al
2
O
3
and iron oxide is preferably at least circa 0.5, advantageously circa 0.5 to 7% by weight and the weight ratio is preferably circa 0.5 to 2.
The object of the invention is also a method for increasing the solubility of mineral fiber compositions which method is characterized in that to a mineral composition having a total Al
2
O
3
and iron oxide content of at least circa 0.5% by weight, phosphorus is added in such an amount that the weight ratio of P
2
O
5
to the sum of Al
2
O
3
, and iron oxide is circa 0.4 to 6, optimally circa 0.5 to 2.


REFERENCES:
patent: 4482541 (1984-11-01), Telfer et al.
patent: 4678659 (1987-07-01), Drake et al.
patent: 4783429 (1988-11-01), Shibuya
patent: 4867779 (1989-09-01), Meunier
patent: 5055428 (1991-10-01), Porter
patent: 5108957 (1992-04-01), Cohen
patent: 5250488 (1993-10-01), Thelohan
patent: 0 009 418 (1980-04-01), None
patent: 247 817 (1987-12-01), None
patent: 0 412 878 (1991-02-01), None
patent: 0 459 897 (1991-12-01), None
patent: 520247 (1939-04-01), None
patent: 63-242944 (1988-10-01), None
patent: 541808 (1977-01-01), None
patent: WO 87/0500 (1987-08-01), None
patent: WO 89/12032 (1989-12-01), None
Ceramic Bulletin, vol. 57, No. 6(1978), pp. 602-604 Chemical Durability of Glasses in the Systems SiO2-CAO-Na2O-RmOnOhta et al. (no month).
Biomaterials, An interfacial Approach, L.L. Hench & E.C. Ethridge (1982) pp. 68-71, 134-148 (no month).
The Constitution of Glasses, a Dynamic Interpretation, Woldemar A. Weyl & Evelyn Chostner Marboe, pp. 568-571 (no date).
Erfahrungsaustausch, pp. 88-90 10(1959), No. 2 (no month).
Models for Physical Properties and Bioactivity of Phosphate Opal Glasses Glastech. Ber. 61 (1988) No. 10; pp. 300-305 (no month).
Effect of Minor Substitution of Si2in the Na2O SiO2Glass on the Leaching Characteristics in Aqueous Medium, vol. 13, No. 4, (1968), pp. 97-102 (no month).
Scientific Basis for Nuclear Waste Management VII, Gary L. McVay; vol. 26, 1984, pp. 755-761 (no month).
Ullmans (1976) pp. 359-365 (no month).

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Mineral fiber composition does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Mineral fiber composition, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mineral fiber composition will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2843853

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.