CS240546B1 - Low-cut glass for glass fibers - Google Patents

Abstract

The low-boron glass for glass fiber according to the invention is intended primarily for polyester resins as reinforcement for laminates, or for other applications in glass-reinforced plastic technologies. The purpose of the invention is to replace the currently used E-glass and thereby reduce production costs and solve environmental problems. This purpose is achieved by producing the fibers from glass containing 4 to 6% by weight of boric oxide B2O3, 52 to 56% by weight of silicon dioxide S1O2, 10.6 to 13.5% by weight of calcium oxide CaO, 6.1 to 8.9% by weight of magnesium oxide MgO, 15.1 to 16.8% by weight of aluminum oxide Al2O3, 2.5 to 3.5% by weight of barium oxide BaO, 0.7 to 1.5% by weight of zinc oxide ZnO or titanium dioxide PO2.

Description

The invention relates to low-boron glass for continuous glass fibers intended primarily for use in polyester resins as reinforcement for laminates, or other applications in glass-reinforced plastic technologies.

E-glass currently has a dominant position in the production of continuous glass fibers. It is a non-alkaline alumina-boron-calcium-silica glass with a mass content of aluminum oxide 15.5 + 0.5%, boron oxide 8.5 + 0.5%, calcium oxide 17.5 + + 0.5 °/o and silicon dioxide 53.5 + 0.5%, with the following physical parameters.

density at 20 °C liquidus temperature crystallization rate refractive index n _D ²⁰ ° hydrolytic class

2570 kg/m ³ max. 1140 °C max. 0.7 μπι/min 1.544

II.

The disadvantage of said glass is primarily in two factors. The first of them is the growing shortage and, as a result, the ever-rising price of boron raw materials, the second is air pollution by the emission of boron compounds and fluorides, which are used in the chlorination mixture during the smelting process. •Due to the reduction of costs for the production of continuous glass fibers and the elimination of ecological problems, the effort to substantially limit research and production activities, or exclude undesirable factors — the content of boron oxide B2O3 and fluorides.

The above-mentioned shortcomings are eliminated by the low-boron glass according to the invention, the essence of which is that it contains 4 to 6% by weight of boron oxide B2O3, 52 to 56% by weight of silica SiO2, UJ,6 to

13.5% by weight of calcium oxide CaO, 6.1 to 8.9% by weight of magnesium oxide ¹ MgO,

15.1 to 16.8% by weight of aluminum oxide AI2O3, 2.5 to 3ť5% by weight of barium oxide BaO, 0.7 to 1.5% by weight of zinc oxide ZnO or titanium dioxide T1O2.

The advantage of the invention lies in the fact that the content of boron oxide B2O3 in the glass is significantly reduced and it is not necessary to use a chlorination mixture containing fluorides, while maintaining the required parameters of the glass.

The invention is further clarified by examples of implementation and supported by a figure that shows the dependence of the viscosity of low-boron glass on temperature in comparison with the dependence of the viscosity of E-glass on temperature.

Example 1

From a stock prepared from sand, kaolin, dolomite, magnesium carbonate, boric acid, zinc sulfate and antimonite, glass of the following composition was fused:

silicon dioxide SiOz calcium oxide CaO aluminum oxide AI2O3 boron oxide B2O3, magnesium oxide MgO zinc oxide ZnO barium oxide BaO

55.3

10.6

15.1

4.1 8.9

1.2 3.2%/%

1% í°/o !% ío/o

The glass was fused in a natural gas-fired ladle furnace at 1550°C and the glass was hand-formed into balls that were used to pull the filament from a PtRh 30 crucible with a 1.6 mm diameter and 5 mm high spout. The fiber was drawn at temperatures of 1140 to 1200°C.

Physical parameters of glass 1 density at 20 °C liquidus temperature crystallization rate refractive index n _D ²⁰ ° hydrolytic class

648.5 kg/ ^m3 1158 °C

0.4 μπι/min 1.5616

II.

In the attached picture, the measured viscosity curve of low-boron glass 1 is compared with the viscosity curve of E-glass.

Example 2

Glass No. 2, 3, 4, 5, the composition of which is given in the table, were melted on the bath regenerative melting aggregate from the raw materials sand, dolomite, magnesium carbonate, barium carbonate, boric acid, titanium dioxide, kaolin, sulfate and antimony. Balls were made from the glasses, which were processed on a PtRh piecke Sk-200, and the produced fibers were used in laminates.

2 3 4 5 6 SiO2 52.9 51.8 53.1 53.7 54.5 B2O3 6.0 5.5 . 5.0 4.7 4.5 CaO 13.5 13.2 ' 12.1 11.6 11.3 MgO 6.1 7.3 7.3 7.6 7.8 AI2O3 16.1 16.8 16.1 16.1 16.0 T1O2 0.9 0.98 1.0 1.0 0.95 Fe2iO3 .0.4 0.32 0.30 0.31 0.3 BaO 2.54 2.8 3.0 3.1 3.5 liquidus (°C) 1190 1180 1165 1154 1136 density (kg/ ^m3 ) 2621.3 2627.1 2635.1 2632.2 2632.5

After all, the physico-chemical parameters are comparable to glass E,

Claims (1)

SUBJECT Low-yellow glass fiber glass, characterized in that it contains 4 to 6% by weight of boron oxide B2O3, 52 to 56% by weight of SiO2 silica, 10.6 to 13.5% by weight of CaO, 6.1 to 8.9 INVENTION percent by weight of MgO, 15.1 to 16.8% by weight of Al2O3, 2.5 to 3.5% by weight of barium oxide BaO, 0.7 to 1.5% by weight of ZnO or TiO2.