| abstract |
In order to obtain an insulating resin material that is a material having both superior low relative dielectric constant and low linear thermal expansion coefficient, which have conventionally been difficult to obtain, a metal-layer-attached insulating resin material using the same, and a wiring substrate, the present invention provides an insulating resin material containing: inorganic porous agglomerates 2 that are composed of a plurality of fine particles and that have holes 3; and fibrils 4 formed of polytetrafluoroethylene, wherein the fibrils 4 are oriented in many directions, and at least either the inorganic porous agglomerates 2 or the fibrils 4 are linked to one another and form a minute network structure having a porosity of 50% or more. |