Method for preparing copper foil with insulating layer and copper foil with insulating layer prepared by the method, and printed wiring board using the copper foil with insulating layer
To provide a method of manufacturing a material which can make a skeletal component as thin as possible to be contained in an insulating layer in a manufactured copper clad laminate and can securely prevent the direct contact between the nodular treatment surface of the attached copper foil and a skeletal component. In order to attain the object, here is adopted “a method of manufacturing a copper foil with an insulating layer 1 which method is a method of manufacturing a copper foil provided with a semi-cured insulating resin layer containing a skeletal component on one side surface of the copper foil, and is characterized in that: a first thermosetting resin layer 3 in an uncured or semi-cured state is provided on one side surface of a copper foil 2 ; a nonwoven fabric 5 or a woven cloth 5 to be a skeletal component is press-bonded onto a first thermosetting resin layer 3 ; a second thermosetting resin layer 7 is formed on a surface of a press-bonded nonwoven fabric 5 or woven cloth 5 ; and a semi-cured insulating layer containing the nonwoven fabric 5 or the woven cloth 5 is formed on one side surface of the copper foil 2 by drying into a semi-cured state.”
1. A method of manufacturing a copper foil provided with a semi-cured insulating layer containing a backbone material on one side surface of the copper foil, said method comprising the steps of:
1) providing on one side surface of the copper foil a liquid thermosetting resin layer containing a solvent;
2) semi-curing said liquid thermosetting resin layer by drying to remove said solvent preliminarily;
3) placing a nonwoven fabric or woven cloth serving as a backbone material onto said semi-cured thermosetting resin layer;
4) heating said semi-cured thermosetting resin to flow and to allow said nonwoven fabric or woven cloth as the backbone material to be impregnated with the resin, and further allow the resin to exude to an opposite side of said nonwoven fabric or woven cloth to form a semi-cured insulating layer containing said nonwoven fabric or woven cloth on one side of the copper foil; and
5) adjusting said thermosetting resin layer to be X−30 (μm) to X−3 (μm) in thickness in relation to a thickness (X (μm)) of the formed insulating layer.