Abstract: A glass cloth comprising a glass yarn woven together, the glass yarn comprising multiple glass filaments, wherein an amount of B2O3 in a composition of the glass filaments is 15% by mass to 30% by mass, an amount of SiO2 in the composition thereof is 45% by mass to 60% by mass, and an amount of P2O5 in the composition thereof is 2% by mass to 8% by mass, and loss on ignition (LOI) of the glass cloth is 0.90% by mass to 2.0% by mass.

Abstract: A glass cloth comprising a glass yarn woven together, the glass yarn comprising multiple glass filaments, wherein an amount of B2O3 in a composition of the glass filaments is 15% by mass to 30% by mass, an amount of SiO2 in the composition thereof is 45% by mass to 60% by mass, and an amount of P2O5 in the composition thereof is 2% by mass to 8% by mass, and loss on ignition (LOI) of the glass cloth is 0.90% by mass to 2.0% by mass.

Abstract: The present invention provide a glass cloth comprising a warp yarn and a weft yarn woven together, the warp yarn and the weft yarn each being a glass yarn including multiple glass filaments, wherein at least one of the warp yarn and the weft yarn comprises filaments each having an amount of SiO2 in the composition thereof of 98 to 100% by mass, an average filament diameter of the glass filaments is 3 to 10 ?m, number of the filaments is 20 to 300, each of the weaving densities of the warp yarn and the weft yarn configuring the glass cloth is independently 20 to 140/inch, a thickness of the glass cloth is 5 to 100 ?m, an ignition loss of the glass cloth is 0.12% by mass or more but 1.0% by mass or less, a permittivity of the glass cloth is 4.4 or less, and a surface of the glass yarn is treated with a silane coupling agent having an unsaturated double bond group.

Abstract: A glass cloth obtained by weaving a glass yarn including a plurality of glass filaments, wherein the compositional amount of B2O3 is 20% by mass to 30% by mass in the glass filaments and the compositional amount of SiO2 is 50% by mass to 60% by mass in the glass filaments, and the loss on ignition of the glass cloth is 0.25% by mass to 1.0% by mass.

Abstract: There is provided a prepreg for electronic materials which has superior flame retardancy and heat resistance. The prepreg relevant to the present invention comprises a glass composition filler which has a mean particle diameter of 2.0 ?m or less and a CaO content of 5% by mass or more, a glass cloth, and a matrix resin, characterized in that an amount of said glass composition filler to be filled is 10% by volume to 70% by volume relative to the total volume of said glass composition filler and said matrix resin.