Abstract: Provided are a surface-treated glass cloth capable of enhancing insulation reliability when used to prepare a prepreg, a prepreg and a printed wiring board using the surface-treated glass cloth. The surface-treated glass cloth includes a surface treatment layer on a surface, a glass constituting the glass cloth has a composition containing 52.0 to 60.0 mass % of SiO2, 15.0 to 26.0 mass % of B2O3, 9.0 to 18.0 mass % of Al2O3, 1.0 to 8.0 mass % of MgO, 1.0 to 10.0 mass % of CaO, 0 to 6.0 mass % of SrO, 0 to 6.0 mass % of TiO2, and 0.1 to 3.0 mass % in total of F2 and Cl2, based on the total amount of the glass, the glass cloth has a surface coverage of 75.0 to 100.0% and a thickness of 8 to 95 ?m, and the surface treatment layer contains a silane coupling agent having a methacrylic group and contains no surfactant.

Abstract: The surface-treated glass cloth includes a surface treatment layer on a surface, and the surface treatment layer includes: a first silane coupling agent containing at least one amine selected from the group consisting of a primary amine, a secondary amine and a tertiary amine and containing no quaternary ammonium cation; a second silane coupling agent containing at least one quaternary ammonium cation; an organic acid; and a surfactant. A total content of the first silane coupling agent and the second silane coupling agent is 0.05 to 1.20 mass% based on the total amount of the surface-treated glass cloth, a ratio of a molar content of the first silane coupling agent to a molar content of the second silane coupling agent is 1.1 to 10.0, and a content of the organic acid is 50 to 300 ppm based on the total amount of the surface-treated glass cloth.

Abstract: The surface-treated glass cloth includes a surface treatment layer on a surface, and the surface treatment layer includes: a first silane coupling agent containing at least one amine selected from the group consisting of a primary amine, a secondary amine and a tertiary amine and containing no quaternary ammonium cation; a second silane coupling agent containing at least one quaternary ammonium cation; an organic acid; and a surfactant. A total content of the first silane coupling agent and the second silane coupling agent is 0.05 to 1.20 mass% based on the total amount of the surface-treated glass cloth, a ratio of a molar content of the first silane coupling agent to a molar content of the second silane coupling agent is 1.1 to 10.0, and a content of the organic acid is 50 to 300 ppm based on the total amount of the surface-treated glass cloth.

Abstract: Provided are a surface-treated glass cloth capable of enhancing insulation reliability when used to prepare a prepreg, a prepreg and a printed wiring board using the surface-treated glass cloth. The surface-treated glass cloth includes a surface treatment layer on a surface, a glass constituting the glass cloth has a composition containing 52.0 to 60.0 mass % of SiO2, 15.0 to 26.0 mass % of B2O3, 9.0 to 18.0 mass % of Al2O3, 1.0 to 8.0 mass % of MgO, 1.0 to 10.0 mass % of CaO, 0 to 6.0 mass % of SrO, 0 to 6.0 mass % of TiO2, and 0.1 to 3.0 mass % in total of F2 and Cl2, based on the total amount of the glass, the glass cloth has a surface coverage of 75.0 to 100.0% and a thickness of 8 to 95 ?m, and the surface treatment layer contains a silane coupling agent having a methacrylic group and contains no surfactant.

Abstract: Provided is a glass cloth enabling to reduce a mass of the glass cloth, being manufactured efficiently, suppressing generation of pinholes in a prepreg including the glass cloth, and maintaining excellent appearance. The glass cloth is composed of warps and wefts obtained by bundling 30 to 44 glass filaments having a diameter in the range of 3.0 to 4.0 ?m, the weave densities of the warp and the weft being in the range of 100 to 125 yarns/25 mm; the glass cloth has a thickness in the range of 6.5 to 11.0 ?m; the glass yarn coverage C is 85.5 to 99.5%; and the glass yarn coverage C, the average value F of the number of glass filaments constituting the warp and the weft, and the average value D of the weave densities of the warp and the weft satisfy the following expression (1): 53.0?C×F1/2/D1/2?57.3??(1).

Abstract: Provided is a glass cloth enabling to reduce a mass of the glass cloth, being manufactured efficiently, suppressing generation of pinholes in a prepreg including the glass cloth, and maintaining excellent appearance. The glass cloth is composed of warps and wefts obtained by bundling 30 to 44 glass filaments having a diameter in the range of 3.0 to 4.0 ?m, the weave densities of the warp and the weft being in the range of 100 to 125 yarns/25 mm; the glass cloth has a thickness in the range of 6.5 to 11.0 ?m; the glass yarn coverage C is 85.5 to 99.5%; and the glass yarn coverage C, the average value F of the number of glass filaments constituting the warp and the weft, and the average value D of the weave densities of the warp and the weft satisfy the following expression (1): 53.0?C×F1/2/D1/2?57.3 ??(1).