The invention provides methods of making man-made vitreous fibres (MMVF), comprising providing an electric furnace having molybdenum electrodes, providing mineral raw material, wherein the mineral raw material comprises (a) particulate material that comprises metallic aluminium and (b) other mineral component, introducing the mineral raw material into the furnace, melting the mineral raw material to form a mineral melt, and forming MMVF from the mineral melt, with the benefit of reduced shrinkage of consolidated MMVF products.

The invention provides methods of making man-made vitreous fibres (MMVF), comprising providing an electric furnace having molybdenum electrodes, providing mineral raw material, wherein the mineral raw material comprises (a) particulate material that comprises metallic aluminium and (b) other mineral component, introducing the mineral raw material into the furnace, melting the mineral raw material to form a mineral melt, and forming MMVF from the mineral melt, with the benefit of reduced shrinkage of consolidated MMVF products.

A high modulus composite part is disclosed comprising a polymer resin; and a plurality of high-performance unidirectional glass fibers. The high-performance unidirectional glass fibers have an elastic modulus of at least 89 GPa and a tensile strength of at least 4,000 MPa, according to ASTM D2343-09. The composite part comprises a fiber weight fraction (FWF) of no more than 88% and an elastic modulus of at least 60 GPa, according to ASTM D7205.

The present disclosure provides a novel glass composition that has a low permittivity and is suitable for mass production. A glass composition provided satisfies, in wt %, for example, 40≤SiO.sub.2≤60, 25≤B.sub.2O.sub.3≤45, 0≤Al.sub.2O.sub.3≤18, 0<R.sub.2O≤5, and 0≤RO≤12, and satisfies at least one of: i) SiO.sub.2+B.sub.2O.sub.3≥80 and SiO.sub.2+B.sub.2O.sub.3+Al.sub.2O.sub.3≤99.9; and ii) SiO.sub.2+B.sub.2O.sub.3≥78, SiO.sub.2+B.sub.2O.sub.3+Al.sub.2O.sub.3≤99.9, and 0<RO<10. Another glass composition provided includes SiO.sub.2, B.sub.2O.sub.3, Al.sub.2O.sub.3, R.sub.2O, and 3<RO<8 at the same contents as the above, and satisfies SiO.sub.2+B.sub.2O.sub.3≥75 and SiO.sub.2+B.sub.2O.sub.3+Al.sub.2O.sub.3<97, where R.sub.2O═Li.sub.2O+Na.sub.2O+K.sub.2O and RO═MgO+CaO+SrO.

The present disclosure provides a novel glass composition that has a low permittivity and is suitable for mass production. A glass composition provided satisfies, in wt %, for example, 40≤SiO.sub.2≤60, 25≤B.sub.2O.sub.3≤45, 0≤Al.sub.2O.sub.3≤18, 0<R.sub.2O≤5, and 0≤RO≤12, and satisfies at least one of: i) SiO.sub.2+B.sub.2O.sub.3≥80 and SiO.sub.2+B.sub.2O.sub.3+Al.sub.2O.sub.3≤99.9; and ii) SiO.sub.2+B.sub.2O.sub.3≥78, SiO.sub.2+B.sub.2O.sub.3+Al.sub.2O.sub.3≤99.9, and 0<RO<10. Another glass composition provided includes SiO.sub.2, B.sub.2O.sub.3, Al.sub.2O.sub.3, R.sub.2O, and 3<RO<8 at the same contents as the above, and satisfies SiO.sub.2+B.sub.2O.sub.3≥75 and SiO.sub.2+B.sub.2O.sub.3+Al.sub.2O.sub.3<97, where R.sub.2O═Li.sub.2O+Na.sub.2O+K.sub.2O and RO═MgO+CaO+SrO.

A glass filler of the present invention includes: a glass substrate; and a coating film including a surface treatment agent, the coating film covering at least a portion of a surface of the glass substrate. The glass substrate is a glass fiber having a flat cross-sectional shape. For the glass substrate, when a length corresponding to a minor axis of the flat cross-section of the glass fiber is represented by L1, a length corresponding to a major axis of the flat cross-section of the glass fiber is represented by L2, and a length corresponding to a fiber length of the glass fiber is represented by L3, a ratio of an average of L2 to an average of L1, (average of L2)/(average of L1), is 1.5 or more and 8 or less, the average of L1 is 1.0 μm or more and 10 μm or less, an average of L3 is 3 μm or more and less than 80 μm, and an average of L3 is larger than the average of L2. The surface treatment agent includes a silane coupling agent. A proportion of the coating film in the glass filler is 0.05 mass % or more and 2.5 mass % or less.

A glass filler of the present invention includes: a glass substrate; and a coating film including a surface treatment agent, the coating film covering at least a portion of a surface of the glass substrate. The glass substrate is a glass fiber having a flat cross-sectional shape. For the glass substrate, when a length corresponding to a minor axis of the flat cross-section of the glass fiber is represented by L1, a length corresponding to a major axis of the flat cross-section of the glass fiber is represented by L2, and a length corresponding to a fiber length of the glass fiber is represented by L3, a ratio of an average of L2 to an average of L1, (average of L2)/(average of L1), is 1.5 or more and 8 or less, the average of L1 is 1.0 μm or more and 10 μm or less, an average of L3 is 3 μm or more and less than 80 μm, and an average of L3 is larger than the average of L2. The surface treatment agent includes a silane coupling agent. A proportion of the coating film in the glass filler is 0.05 mass % or more and 2.5 mass % or less.

Disclosed herein is a glass composition including, based on a total weight of the glass composition, 49 wt % to 59 wt % of SiO.sub.2, 9.5 wt % to 14.5 wt % of Al.sub.2O.sub.3, 19 wt % to 35 wt % of B.sub.2O.sub.3, 2 wt % to 5 wt % of CaO, 0.25 wt % to 3 wt % of ZnO, 0 wt % to 1 wt % of MgO, 0 wt % to 1 wt % of TiO.sub.2, 0 wt % to 3 wt % of ZrO.sub.2, and 0.1 wt % to 3.5 wt % of MnO. Also disclosed herein are a glass fiber and a glass article which include the glass composition.

Disclosed herein is a glass composition including, based on a total weight of the glass composition, 49 wt % to 59 wt % of SiO.sub.2, 9.5 wt % to 14.5 wt % of Al.sub.2O.sub.3, 19 wt % to 35 wt % of B.sub.2O.sub.3, 2 wt % to 5 wt % of CaO, 0.25 wt % to 3 wt % of ZnO, 0 wt % to 1 wt % of MgO, 0 wt % to 1 wt % of TiO.sub.2, 0 wt % to 3 wt % of ZrO.sub.2, and 0.1 wt % to 3.5 wt % of MnO. Also disclosed herein are a glass fiber and a glass article which include the glass composition.

The present disclosure provides a novel glass filler that has a low permittivity and is suitable for mass production. A glass filler provided includes a glass composition that includes, in wt %, for example, 40≤SiO.sub.2≤60, 25≤B.sub.2O.sub.3≤45, 0<Al.sub.2O.sub.3≤18, 0<R.sub.2O≤5, and 0≤RO≤12, and satisfies at least one of: i) SiO.sub.2+B.sub.2O.sub.3≥80 and SiO.sub.2+B.sub.2O.sub.3+Al.sub.2O.sub.3≤99.9; and ii) SiO.sub.2+B.sub.2O.sub.3≥78, SiO.sub.2+B.sub.2O.sub.3+Al.sub.2O.sub.3≤99.9, and 0<RO<10. Another glass filler provided includes a glass composition that includes SiO.sub.2, B.sub.2O.sub.3, Al.sub.2O.sub.3, R.sub.2O, and 3<RO<8 at the same contents as the above, and satisfies SiO.sub.2+B.sub.2O.sub.3≥75 and SiO.sub.2+B.sub.2O.sub.3+Al.sub.2O.sub.3<97, where R.sub.2O=Li.sub.2O+Na.sub.2O+K.sub.2O and RO=MgO+CaO+SrO.