The invention relates to a method for producing glass fibers that laterally emit light and to glass fibers produced according to said method. The problem of providing a method that relies on standard available glass components, thus making possible an economical production method that allows a glass fiber to be produced which emits laterally and, in an optically active manner, spectrally shifts, scatters and/or filters light coupled into the fiber when said light exits through the fiber cladding, is solved in that, first, glass tubes (7) and glass rods (5) of identical chemical composition and identical optical refractive index are selected, then first the glass rod (5) is coated completely or over parts of its outer periphery with a vitrifiable material mixture containing optically active substances, in the liquid phase, and the glass rod (5) coated in such a way with this coating (6) after said coating has been dried or consolidated is brought into the glass tube (7) and both are jointly drawn, under the application of heat, to form a glass fiber in a known way.

The present invention relates to a silver coated glass frit used in a paste composition for forming a solar cell electrode, a method for preparing the same, and a silver paste composition using a silver coated glass frit for a solar cell. More specifically, the present invention relates to: a method for preparing a silver-coated glass frit wherein a silver coated glass frit, in which silver (Ag) is coated on a surface of the glass frit, is prepared through a reduction reaction occurring by adding, to a first solution containing silver nitrate (AgNO3) mixed with a glass frit and an amine, a second solution containing a reductant, and during the preparation process, a silver (Ag) coating layer is more uniformly formed on the surface of the glass frit by controlling the acidity of the first solution and the reaction temperature in the reduction reaction, thereby achieving an improved specific surface area; a silver-coated glass frit prepared by the method; and a silver paste composition for a solar cell wherein the composition is prepared by using the sliver-coated glass frit, and thus has significantly improved sintering characteristics and electrical conductivity.

A glass composition is provided. The glass composition includes: 25-40 wt % SiO.sub.2; 2.5-10 wt % B.sub.2O.sub.3; 0-10 wt % Al.sub.2O.sub.3; 0-15 wt % Li.sub.2O; 0-16 wt % of Li.sub.2O, Na.sub.2O, and K.sub.2O in total; 10-25 wt % CaO; 0-15 wt % BaO; 0-5 wt % MgO; 0-5 wt % SrO; 10-30 wt % CaO, BaO, MgO, and SrO in total; 0-7 wt % ZnO; 2-10 wt % ZrO; 2-15 wt % TiO.sub.2; 5-25 wt % Nb.sub.2O.sub.5; 0-5 wt % Ta.sub.2O.sub.5; 5-25 La.sub.2O.sub.3; and 0-5 wt % Y.sub.2O.sub.3. The glass composition has a refractive index from about 1.74 to about 1.80, a density from about 3.5 g/cm.sup.3 to about 4.0 g/cm.sup.3, a critical cooling rate from about 1° C./min to about 50° C./min, and a liquidus viscosity greater than 25 Poises.

A glass composition is provided. The glass composition includes: 25-40 wt % SiO.sub.2; 2.5-10 wt % B.sub.2O.sub.3; 0-10 wt % Al.sub.2O.sub.3; 0-15 wt % Li.sub.2O; 0-16 wt % of Li.sub.2O, Na.sub.2O, and K.sub.2O in total; 10-25 wt % CaO; 0-15 wt % BaO; 0-5 wt % MgO; 0-5 wt % SrO; 10-30 wt % CaO, BaO, MgO, and SrO in total; 0-7 wt % ZnO; 2-10 wt % ZrO; 2-15 wt % TiO.sub.2; 5-25 wt % Nb.sub.2O.sub.5; 0-5 wt % Ta.sub.2O.sub.5; 5-25 La.sub.2O.sub.3; and 0-5 wt % Y.sub.2O.sub.3. The glass composition has a refractive index from about 1.74 to about 1.80, a density from about 3.5 g/cm.sup.3 to about 4.0 g/cm.sup.3, a critical cooling rate from about 1° C./min to about 50° C./min, and a liquidus viscosity greater than 25 Poises.

The present invention relates to a light guide plate containing a glass plate and a resin layer that is formed on at least one major surface of the glass plate, in which the resin layer is made of a resin containing metal oxide fine particles dispersed, and an absolute value of a refractive index difference between the glass plate and the resin layer is 0.07 or smaller over an entire range of a wavelength of 430 nm to 700 nm.

The present invention relates to a light guide plate containing a glass plate and a resin layer that is formed on at least one major surface of the glass plate, in which the resin layer is made of a resin containing metal oxide fine particles dispersed, and an absolute value of a refractive index difference between the glass plate and the resin layer is 0.07 or smaller over an entire range of a wavelength of 430 nm to 700 nm.

A cover glass of the present invention is characterized by including in a glass composition at least three or more components selected from SiO.sub.2, Al.sub.2O.sub.3, B.sub.2O.sub.3, Li.sub.2O, Na.sub.2O, K.sub.2O, MgO, CaO, BaO, TiC.sub.2, Y.sub.2O.sub.3, ZrO.sub.2, and P.sub.2O.sub.5, and having an X value of 7, 400 or more calculated by the following equation. The X value is a value calculated by the equation

X=61.1×[SiO.sub.2]+174.3×[Al.sub.2O.sub.3]+11.3×[B.sub.2O.sub.3]+124.7×[Li.sub.2O]−5.2×[Na.sub.2O]+226.7×[K.sub.2O]+139.4×[MgO]+117.5×[CaO]+89.6×[BaO]+191.8×[TiO.sub.2]+226.7×[Y.sub.2O.sub.3]+157.9×[ZrO.sub.2]−42.2×[P.sub.2O.sub.5].

A cover glass of the present invention is characterized by including in a glass composition at least three or more components selected from SiO.sub.2, Al.sub.2O.sub.3, B.sub.2O.sub.3, Li.sub.2O, Na.sub.2O, K.sub.2O, MgO, CaO, BaO, TiC.sub.2, Y.sub.2O.sub.3, ZrO.sub.2, and P.sub.2O.sub.5, and having an X value of 7, 400 or more calculated by the following equation. The X value is a value calculated by the equation

X=61.1×[SiO.sub.2]+174.3×[Al.sub.2O.sub.3]+11.3×[B.sub.2O.sub.3]+124.7×[Li.sub.2O]−5.2×[Na.sub.2O]+226.7×[K.sub.2O]+139.4×[MgO]+117.5×[CaO]+89.6×[BaO]+191.8×[TiO.sub.2]+226.7×[Y.sub.2O.sub.3]+157.9×[ZrO.sub.2]−42.2×[P.sub.2O.sub.5].

Provided is an optical glass, wherein, based on mass, an SiO.sub.2 content is 10.00% or more, a CaO content is 5.00% or more, a total content (La.sub.2O.sub.3+Gd.sub.2O.sub.3+Y.sub.2O.sub.3) of La.sub.2O.sub.3, Gd.sub.2O.sub.3 and Y.sub.2O.sub.3 is more than 0%, a total content (BaO+La.sub.2O.sub.3+Gd.sub.2O.sub.3+Y.sub.2O.sub.3) of BaO, La.sub.2O.sub.3, Gd.sub.2O.sub.3 and Y.sub.2O.sub.3 is 30.00% or less, and a mass ratio ((SiO.sub.2+B.sub.2O.sub.3)/(TiO.sub.2+Nb.sub.2O.sub.5+Ta.sub.2O.sub.5+WO.sub.3+Bi.sub.2O.sub.3)) of a total content of SiO.sub.2 and B.sub.2O.sub.3 relative to a total content of TiO.sub.2, Nb.sub.2O.sub.5, Ta.sub.2O.sub.5, WO.sub.3 and Bi.sub.2O.sub.3 is 0.75 or less.

Provided is an optical glass, wherein, based on mass, an SiO.sub.2 content is 10.00% or more, a CaO content is 5.00% or more, a total content (La.sub.2O.sub.3+Gd.sub.2O.sub.3+Y.sub.2O.sub.3) of La.sub.2O.sub.3, Gd.sub.2O.sub.3 and Y.sub.2O.sub.3 is more than 0%, a total content (BaO+La.sub.2O.sub.3+Gd.sub.2O.sub.3+Y.sub.2O.sub.3) of BaO, La.sub.2O.sub.3, Gd.sub.2O.sub.3 and Y.sub.2O.sub.3 is 30.00% or less, and a mass ratio ((SiO.sub.2+B.sub.2O.sub.3)/(TiO.sub.2+Nb.sub.2O.sub.5+Ta.sub.2O.sub.5+WO.sub.3+Bi.sub.2O.sub.3)) of a total content of SiO.sub.2 and B.sub.2O.sub.3 relative to a total content of TiO.sub.2, Nb.sub.2O.sub.5, Ta.sub.2O.sub.5, WO.sub.3 and Bi.sub.2O.sub.3 is 0.75 or less.