Method of manufacturing copper foil with insulating layer, copper foil with insulating layer obtained with the same method, and printed circuit board using the same 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.
1. A method of manufacturing a copper foil provided with a semi-cured insulating layer containing a skeletal component on one side surface of the copper foil which method is a method of manufacturing a copper foil with an insulating layer, wherein a first semi-cured thermosetting resin layer is provided on one side surface of the copper foil; a nonwoven fabric not impregnated with resin or a woven cloth not impregnated with resin to be the skeletal component is press-bonded onto said first semi-cured thermosetting resin layer; a second thermosetting resin is applied onto a surface of the press-bonded nonwoven fabric or woven cloth to form a second thermosetting resin layer; wherein said second thermosetting resin is applied onto the surface of the press-bonded nonwoven fabric or woven cloth as a liquid resin which liquid resin comprises a combination of a resin and a solvent; and a semi-cured insulating layer which contains a nonwoven fabric or a woven cloth on one side surface of the copper foil is formed by subsequently drying the second thermosetting resin layer into a semi-cured state.
2. The method of manufacturing a copper foil with an insulating layer according to claim 1 , wherein the thickness of the first thermosetting resin layer is 5 μm or above as converted to a flat plane thickness, and thinner than the thickness of the nonwoven fabric or the woven cloth used as the skeletal component.
3. The method of manufacturing a copper foil with an insulating layer according to claim 1 , wherein the nonwoven fabric or the woven cloth is made of any of a glass fiber, an aramid fiber, or a wholly aromatic polyester fiber having a melting point of 300° C. or above.