Compositions: ceramic – Ceramic compositions – Glass compositions – compositions containing glass other than...
Patent
1999-09-02
2000-10-24
Group, Karl
Compositions: ceramic
Ceramic compositions
Glass compositions, compositions containing glass other than...
501 35, 501 70, 65454, 65459, C03C 1306, C03C 3087
Patent
active
061367354
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to "reinforcing" glass yarns (or "fibres"), that is to say yarns which can be used for the reinforcement of organic and/or inorganic materials and which can be used as textile yarns, these yarns being susceptible to be obtained by the process which consists in mechanically drawing the streams of molten glass which flow out of orifices located in the base of a bushing which is generally heated by the Joule effect.
The present invention relates more specifically to glass yarns having a particularly advantageous novel composition.
The field of reinforcing glass yarns is a very special field in the glass industry. These yarns are produced from specific glass compositions, the glass used having to be able to be drawn in the form of filaments of few micrometers in diameter using the process defined above and having to allow the formation of continuous yarns suitable in particular for fulfilling their reinforcing function. The reinforcing glass yarns most commonly used are thus the yarns formed from glasses which derive from the 1170.degree. C. eutectic of the SiO.sub.2 --Al.sub.2 O.sub.3 --CaO ternary diagram, in particular the yarns called E-glass yarns, the archetype of which is described in U.S. Pat. No. 2,334,981 and U.S. Pat. No. 2,571,074. E-glass yarns have a composition essentially based on silica, alumina, lime and boric anhydride, the boric anhydride, present in amounts ranging in practice from 5 to 13% in the compositions of glasses termed "E-glass", replacing part of the silica, the E-glass yarns being furthermore characterized by a limited content of alkali metal oxides (essentially Na.sub.2 O and/or K.sub.2 O).
Since the two patents mentioned, glasses comprising these constituents have formed the subject of numerous modifications whose purpose is to reduce emanations of products likely to pollute the atmosphere, to reduce the cost of the composition, by decreasing the content of the more expensive constituents, to improve the capability of these glasses to undergo fiberizing (fiberizing or forming corresponding to the operation of drawing the glass filaments from a bushing in the abovementioned process), especially by decreasing their viscosity at high temperatures as well as their tendency to devitrify, to improve such and such a particular property. Attempts have been made to reduce the cost of the compositions in particular, but these are generally to the detriment of their fiberizability, the processing of these glasses, in order to obtain reinforcing yarns, generally becoming more difficult or tricky, possibly requiring the existing fiberizing plants or working conditions to be modified and possibly incurring reductions in yield and an increase in the amount of scraps obtained, finally resulting in an increase in the overall production cost. The development of compositions which are much cheaper than the E-glass compositions but which can be fiberized without any difficulty, like the conventional E glass compositions (and which therefore have a lower overall production cost), therefore still remains to be achieved and is particularly desirable.
The subject of the present invention is thus yarns of a glass composition satisfying the above requirement, i.e. yarns of a glass composition (and of a production) which is as inexpensive as possible while at the same time maintaining a particularly good fiberizability.
These objectives are achieved by virtue of glass yarns whose composition represents one of the best possible compromises between its cost and its fiberizability, this composition essentially comprising the following constituents within the limits defined hereinbelow, expressed in percentages by weight:
______________________________________ SiO.sub.2 58 to 62%
Al.sub.2 O.sub.3 10 to 16%
CaO more than 18%
MgO more than 1.5%
CaO + MgO less than 28%
Na.sub.2 O + K.sub.2 O + Li.sub.2 O
less than 2%
TiO.sub.2 less than 1.5%
Fe.sub.2 O.sub.3 less than 0.5%
B.sub.2 O.sub.3 less than 2%
F.sub.2 less than 2%
________________________
REFERENCES:
patent: 3095311 (1963-06-01), Wranau et al.
patent: 4199338 (1980-04-01), Levecque et al.
patent: 4542106 (1985-09-01), Sproull
patent: 5250488 (1993-10-01), Thelohan et al.
patent: 5346864 (1994-09-01), Maugendre et al.
patent: 5352258 (1994-10-01), Degreve et al.
patent: 5420082 (1995-05-01), Maugendre et al.
patent: 5789329 (1998-08-01), Eastes et al.
patent: 5910461 (1999-06-01), Gasca et al.
patent: 5932500 (1999-08-01), Jensen et al.
patent: 5962354 (1999-10-01), Fyles et al.
patent: 6043170 (2000-03-01), Steinkopf et al.
Derwent Abstract 95-262260, Abstract of Russian Patent Spec. 2027687, Jan. 1995.
Bazin Jean-Paul
Creux Sophie
Fournier Pascal
Gallo Marcelo Hernan
Genechten Jan Van
Group Karl
Vetrotex France S.A.
LandOfFree
Glass fibres for reinforcing organic and/or inorganic materials does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Glass fibres for reinforcing organic and/or inorganic materials, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Glass fibres for reinforcing organic and/or inorganic materials will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1963757