Abstract: In a glass cloth made of glass filaments having a composition which is at least 50 wt % SiO2, the filaments have a diameter that is 0.5 ?m or more and less than 3.0 ?m. The glass cloth has a thickness of 15 ?m or less and a weight of from 0.3 to 10 g/m2.

Abstract: A low dielectric substrate for high-speed millimeter-wave communication includes a quartz glass cloth with a dielectric loss tangent of 0.0001 to 0.0015 and a dielectric constant of 3.0 to 3.8 at 10 GHz, and an organic resin with a dielectric loss tangent within 80% to 150% of the dielectric loss tangent of the quartz glass cloth at 10 GHz and a dielectric constant within 50% to 110% of the dielectric constant of the quartz glass cloth at 10 GHz. This provides a low dielectric substrate for high-speed millimeter-wave communication where the low dielectric substrate makes it possible to send signals that are stable and have excellent quality with no difference in propagation time between wirings even if the substrate has an uneven resin distribution and the quartz glass cloth above and below the wirings, and the difference in dielectric loss tangent between members has been reduced to lower transmission loss.

Abstract: The present invention is a resin substrate including an organic resin and a quartz glass cloth, where the organic resin has a dielectric loss tangent of 0.0002 to 0.0020 measured at 10 GHz and a 40 GHz/10 GHz ratio is 0.4 to 0.9, the quartz glass cloth has a dielectric loss tangent of 0.0001 to 0.0015 measured at 10 GHz and a 40 GHz/10 GHz ratio is 1.2 to 2.0, and the resin substrate has a dielectric loss tangent of 0.0001 to 0.0020 at 10 GHz and a 40 GHz/10 GHz ratio is 0.8 to 1.2. This provides a resin substrate having a low dielectric loss tangent in a high-frequency region and dielectric characteristics with little frequency dependence.

Abstract: A fluoroplastic substrate for high-speed communications has a dielectric loss tangent at 40 GHz of from 0.0001 to 0.0008 and a permittivity at 40 GHz of from 2.0 to 3.2. The substrate includes a quartz glass cloth having a dielectric loss tangent at 40 GHz of from 0.0001 to 0.0008 and a fluoroplastic having a dielectric loss tangent at 40 GHz of from 0.0001 to 0.0005.

Abstract: A low dielectric substrate for high-speed millimeter-wave communication includes a quartz glass cloth with a dielectric loss tangent of 0.0001 to 0.0015 and a dielectric constant of 3.0 to 3.8 at 10 GHz, and an organic resin with a dielectric loss tangent within 80% to 150% of the dielectric loss tangent of the quartz glass cloth at 10 GHz and a dielectric constant within 50% to 110% of the dielectric constant of the quartz glass cloth at 10 GHz. This provides a low dielectric substrate for high-speed millimeter-wave communication where the low dielectric substrate makes it possible to send signals that are stable and have excellent quality with no difference in propagation time between wirings even if the substrate has an uneven resin distribution and the quartz glass cloth above and below the wirings, and the difference in dielectric loss tangent between members has been reduced to lower transmission loss.

Abstract: A low dielectric substrate for high-speed millimeter-wave communication includes a quartz glass cloth with a dielectric loss tangent of 0.0001 to 0.0015 and a dielectric constant of 3.0 to 3.8 at 10 GHz, and an organic resin with a dielectric loss tangent within 80% to 150% of the dielectric loss tangent of the quartz glass cloth at 10 GHz and a dielectric constant within 50% to 110% of the dielectric constant of the quartz glass cloth at 10 GHz. This provides a low dielectric substrate for high-speed millimeter-wave communication where the low dielectric substrate makes it possible to send signals that are stable and have excellent quality with no difference in propagation time between wirings even if the substrate has an uneven resin distribution and the quartz glass cloth above and below the wirings, and the difference in dielectric loss tangent between members has been reduced to lower transmission loss.

Abstract: The present invention is a resin substrate including an organic resin and a quartz glass cloth, where the organic resin has a dielectric loss tangent of 0.0002 to 0.0020 measured at 10 GHz and a 40 GHz/10 GHz ratio is 0.4 to 0.9, the quartz glass cloth has a dielectric loss tangent of 0.0001 to 0.0015 measured at 10 GHz and a 40 GHz/10 GHz ratio is 1.2 to 2.0, and the resin substrate has a dielectric loss tangent of 0.0001 to 0.0020 at 10 GHz and a 40 GHz/10 GHz ratio is 0.8 to 1.2. This provides a resin substrate having a low dielectric loss tangent in a high-frequency region and dielectric characteristics with little frequency dependence.

Abstract: A low dielectric substrate for high-speed millimeter-wave communication includes a quartz glass cloth with a dielectric loss tangent of 0.0001 to 0.0015 and a dielectric constant of 3.0 to 3.8 at 10 GHz, and an organic resin with a dielectric loss tangent within 80% to 150% of the dielectric loss tangent of the quartz glass cloth at 10 GHz and a dielectric constant within 50% to 110% of the dielectric constant of the quartz glass cloth at 10 GHz. This provides a low dielectric substrate for high-speed millimeter-wave communication where the low dielectric substrate makes it possible to send signals that are stable and have excellent quality with no difference in propagation time between wirings even if the substrate has an uneven resin distribution and the quartz glass cloth above and below the wirings, and the difference in dielectric loss tangent between members has been reduced to lower transmission loss.

Abstract: The present invention is an annealed quartz glass cloth that has an SiO2 content of 99.5 mass % or more, a dielectric loss tangent of less than 0.0010 at 10 GHz, and a tensile strength of 1.0 N/25 mm or more per cloth weight (g/m2). This provides an annealed quartz glass cloth that has a low dielectric loss tangent and that is also excellent in tensile strength; and a method for manufacturing an annealed quartz glass cloth by which strength recovers after a high-temperature heat treatment.