EP0247817A1
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EP
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Alkali-resistant glass fiber
Assignee: Pfizer Inc
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Filing: 1987-05-26
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Granted: —
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Expires: 2007-05-26
Abstract
Abstract A glass-forming composition having high alkali resistance when formed into a glass body, which comprises a magnesium silicate admixed with a CaO-containing compound or a calcium silicate admixed with a MgO-containing compound. Also included is a process for preparing an alkali-resistant glass fiber, which comprises heating a mixture comprising a magnesium silicate and CaO-containing compound or a calcium silicate and a MgO-containing compound to above the liquidus temperature of the mixture to form a viscous liquid, drawing the viscous liquid to form a fiber, and cooling the fiber below the liquidus temperature.
Inventors
- 👤 Nikhil Chandrakant Trivedi
- 👤 John Douglas Mackenzie
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 01:25
CPC Classifications
C; C03; C03C; C03C13/00; C03C13/001; C03B; C03B37/00; C03B37/01; C03B37/02; C03B37/022; C03B37/075; C03C13/002; C03C3/00; C03C3/04; C03C3/076; C03C3/083; C03C3/085; C03C3/087
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
58 words
A process for preparing an alkali-resistant glass fiber, which comprises heating a mixture comprising a magnesium silicate and a CaO-containing compound or a calcium silicate and a MgO-containing compound to above the liquidus temperature of the mixture to form a viscous liquid, drawing the viscous liquid to form a fiber, and cooling the fiber below the liquidus temperature.
Claim 2
Dependent Claim
58 words
A process for preparing an alkali-resistant glass fiber, which comprises heating a mixture comprising a magnesium silicate and a CaO-containing compound or a calcium silicate and a MgO-containing compound to above the liquidus temperature of the mixture to form a viscous liquid, drawing the viscous liquid to form a fiber, and cooling the fiber below the liquidus temperature.
Claim 3
Dependent Claim
107 words
The process of claim 1 wherein the mixture contains from about 30 to 63 weight percent magnesium silicate, from 0 to about 47 weight percent silica, from about 21 to 45 weight percent calcium carbonate, and from about 5 to 20 weight percent of an oxide selected from the group consisting of lithium oxide, potassium oxide, sodium oxide, barium oxide, cadmium oxide, lead monoxide, strontium oxide, zinc oxide, alumina, boric oxide, ceric oxide, stannic oxide, titania, zirconia, antimony pentoxide, niobium pentoxide, phosphoric pentoxide and tantalum pentoxide, or a combination thereof, any single oxide from the group being added in a maximum amount of about 10 weight percent.
Claim 4
Dependent Claim
33 words
The process of claim 2 wherein the magnesium silicate is in the form of talc, the silica is in the form of sand, and the calcium carbonate is in the form of limestone.
Claim 5
Dependent Claim
19 words
The process of claim 2 wherein the viscous liquid is drawn through an orifice to form a continuous fiber.
Claim 6
Dependent Claim
18 words
The process of claim 4 wherein the cooled continuous fiber is coated with a layer of alkali-resistant polymer.
Claim 7
Dependent Claim
32 words
A glass-forming composition having high alkali resistance when formed into a glass body, which comprises a magnesium silicate admixed with a CaO-containing compound or a calcium silicate admixed with a MgO-containing compound.
Claim 8
Dependent Claim
32 words
A glass-forming composition having high alkali resistance when formed into a glass body, which comprises a magnesium silicate admixed with a CaO-containing compound or a calcium silicate admixed with a MgO-containing compound.
Claim 9
Dependent Claim
106 words
The composition of claim 6 consisting essentially of from about 30 to 63 weight percent magnesium silicate, from 0 to about 47 weight percent silica, from about 21 to 45 weight percent calcium carbonate, and from about 5 to 20 weight percent of an oxide selected from the group consisting of lithium oxide, potassium oxide, sodium oxide, barium oxide, cadmium oxide, lead monoxide, strontium oxide, zinc oxide, alumina, boric oxide, ceric oxide, stannic oxide, titania, zirconia, antimony pentoxide, niobium pentoxide, phosphoric pentoxide and tantalum pentoxide, or a combination thereof, any single oxide from the group being present in a maximum amount of about 10 weight percent.
Claim 10
Dependent Claim
100 words
A continuous, monofilamentous, alkali-resistant glass fiber, which comprises a glass consisting essentially of, in approximate weight percent: SiO₂ 30-65 MgO 12-18 CaO 12-18 minor oxides 5-20 the minor oxides being selected from R a ₂O, R b O, R c ₂O₃ , R d O₂, R e ₂O₅ wherein R a = Li, K, Na, R b = Ba, Cd, Pb, Sr, Zn, R c = Al, B, R d = Ce, Sn, Ti, Zr, R e = Sb, Nb, P, Ta, and wherein a single minor oxide is present in up to about 10 weight percent of the glass.
Claim 11
Dependent Claim
100 words
A continuous, monofilamentous, alkali-resistant glass fiber, which comprises a glass consisting essentially of, in approximate weight percent: SiO₂ 30-65 MgO 12-18 CaO 12-18 minor oxides 5-20 the minor oxides being selected from R a ₂O, R b O, R c ₂O₃ , R d O₂, R e ₂O₅ wherein R a = Li, K, Na, R b = Ba, Cd, Pb, Sr, Zn, R c = Al, B, R d = Ce, Sn, Ti, Zr, R e = Sb, Nb, P, Ta, and wherein a single minor oxide is present in up to about 10 weight percent of the glass.
Claim 12
Dependent Claim
63 words
The glass fiber of claim 8 wherein the glass contains from about 55 to 60 weight percent SiO₂, from about 14 to 16 weight percent MgO and from about 14 to 16 weight percent CaO, and the minor oxides are selected from Na₂O, Al₂O₃, CeO₂, TiO₂ and Ta₂O₅, a single minor oxide being from about 2 to 6 weight percent of the glass.
Claim 13
Dependent Claim
35 words
The glass fiber of claim 9 containing as minor oxides from about 2 to 4 weight percent Na₂O, from about 4 to 6 weight percent Al₂O₃ and from about 3 to 5 weight percent TiO₂.
Claim 14
Dependent Claim
11 words
A fiber-reinforced cementitious product containing the glass fiber of claim 8.
References Cited (Backward Citations)
US3736162A
Cited
FR2318832A1
Cited
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