Printed wiring boards with reduced curing unevenness and the like may be produced by (A) preparing an adhesive sheet having a support and a resin composition layer provided on the support, (B) laminating the adhesive sheet on an internal layer substrate so that the resin composition layer is in contact with the internal layer substrate, and (C) thermally curing the adhesive sheet by heating from T1 (° C.) to T2 (° C.), to form an insulating layer, wherein the adhesive sheet is thermally cured so that a relation of Y>2700X is satisfied in which X is the sum of a difference between a maximum expansion rate of the support in the MD direction during heating from T1 (° C.) to T2 (° C.) and an expansion rate of the support at the end of heating and a difference between a maximum expansion rate of the support in the TD direction during heating from T1 (° C.) to T2 (° C.) and an expansion rate of the support at the end of heating and Y is the lowest melt viscosity of the resin composition layer at 120° C. or higher.

To provide a brazing material for maintaining bonding strength between ceramic substrate and metal plate at a conventionally attainable level, while addition amount of In is reduced, and a brazing material paste using the same. A mixture powder provided by mixing alloy powder composed of Ag, In, and Cu, Ag powder, and active metal hydride powder, the mixture powder containing active metal hydride powder with a 10-to-25-μm equivalent circle average particle diameter by 0.5 to 5.0 mass %, the equivalent circle average particle diameters for the alloy powder, Ag powder, and active metal hydride powder having a relationship: alloy powder≧active metal hydride powder>Ag powder, and the powder mixture having a particle size distribution of d10 of 3 to 10 μm, d50 of 10 to 35 μm, and d90 of 30 to 50 μm, and in the frequency distribution, a peak of the distribution existing between d50 and d90.

Methods, systems and produced printed substrates are provided, which include substrates composed of one or more materials which are treated by an intermediate layer for normalizing surface energies and a digitally printed formulation adapted to the normalized surface energies. Surface energy normalization may be carried out by physical processes or by selective chemical processes. In an example, a self-assembled monolayer is applied to the surface of a printed circuit board to control ink jet dots by reducing copper surface energy and to improve ink adhesion. The self-assembled monolayer binds via an α group selectively and covalently to the copper on the board and binds via a hydrophobic ω group to solder mask ink that is applied to the board. The ω group participates in the solidification process of the ink.

The present invention is related to a composition for micro etching of a copper or a copper alloy surface, wherein the composition comprises i) at least a source of Fe.sup.3+ ions, ii) at least a source of Br.sup.− ions, iii) at least an inorganic acid, and iv) at least one etch refiner according to formula I

##STR00001## wherein R1 is selected from the group consisting of hydrogen, C.sub.1-C.sub.5-alkyl or a substituted aryl or alkaryl group; R2 is selected from the group consisting of hydrogen, C.sub.1-C.sub.5-alkyl or C.sub.1-C.sub.5-alkoxy; R3, R4 are selected from the group consisting of hydrogen and C.sub.1-C.sub.5-alkyl; and X.sup.− is a suitable anion. Further, the present invention is directed to a method for micro etching of copper or copper alloy surfaces using such a composition.

A wiring body includes a conductive portion that includes a contact surface having a concave-convex shape, and an adhesive layer stacked on the contact surface. The conductive portion further includes a top surface facing the contact surface that contains conductive particles. The adhesive layer includes a smooth portion with a smooth main surface provided at a constant thickness, and a protrusion that protrudes from the main surface toward a side of the conductive portion provided on the smooth portion to correspond to the conductive portion. The protrusion comes into contact with the contact surface and includes a concave-convex surface complementary to the concave-convex shape of the contact surface. The contact surface is positioned on a side of the top surface with respect to the main surface and a unit length of the contact surface is larger than a unit length of the top surface.

A wiring body includes an adhesive layer, a first conductor layer disposed on the adhesive layer that includes a first terminal portion, a resin layer covering the first conductor layer except for at least the first terminal portion, and a second conductor layer disposed on the resin layer that includes a second terminal portion. The first terminal portion and the second terminal portion are shifted from each other along a thickness direction of the adhesive layer. The first terminal portion protrudes towards a side separated from the adhesive layer in the thickness direction. In a case where the first terminal portion is projected in a direction orthogonal to the thickness direction, at least a part of a projection portion of the first terminal portion overlaps with the resin layer.

[Problem to be Solved]

A multilayer flexible printed circuit board having a strip line advantageous to folding is provided.

[Solution]

A multilayer flexible printed circuit board 100 of an embodiment is a multilayer flexible printed circuit board having a strip line foldable at a folding part F1, the board including: a flexible insulative substrate 30; an inner layer circuit pattern 5 provided inside the flexible insulative substrate 30 and including a signal line 6 extending in a predetermined direction; a ground thin film 14a constituting a ground layer at least in the folding part F1 out of a ground layer of the strip line and constituted of a nonelectrolytic plating coat 14 formed on the flexible insulative substrate 30; and a protective layer 20 that covers the ground thin film 14a and is in close contact with an exposed part 19 from which the flexible insulative substrate 30 is exposed.

A wiring substrate includes an insulating layer including inorganic fillers and resin, and a conductor layer formed on a surface of the insulating layer and having a conductor pattern. The surface of the insulating layer has an arithmetic average roughness Ra in the range of 0.05 μm to 0.5 μm, the conductor layer includes a metal film formed on the surface of the insulating layer, and the inorganic fillers include a first inorganic filler including particles such that each of the particles has a portion of a surface separated from the resin and forming a gap with respect to the resin of the insulating layer and that the metal film of the conductor layer includes part formed in the gap between the first inorganic filler and the resin.

A method for manufacturing a printed wiring board includes forming the outermost conductor layer on the outermost resin insulating layer, forming a solder resist layer on the outermost resin insulating layer such that the solder resist layer covers the outermost conductor layer formed on the outermost resin insulating layer, irradiating plasma upon an exposed surface of the solder resist layer formed on the outermost conductor layer, forming a catalyst on the exposed surface of the solder resist layer formed on the outermost conductor layer, and forming an electroless plating layer on the exposed surface of the solder resist layer via the catalyst formed on the exposed surface of the solder resist layer such that the electroless plating layer has a film thickness in a range of 0.22 μm to 0.38 μm.

Provided is a circuit substrate, including a glass film (10) forming a rough layer (11) after surface roughness processing, a resin adhesion (20) located the rough layer (11) on either side of the glass film (10), and a metal foil (30) located on the outside of resin adhesion layer (20). The glass film (10), the resin adhesion layer (20) and the metal foil (30) are joined together through suppressing. The circuit substrate employs the glass film (10) which forms a rough layer (11) after surface roughness processing as a carrier material, so that the resin adhesion layer (20) and the surface of the glass film (10) have a good binding force, and the dielectric constant of the circuit substrate has slight difference in the directions of X, Y and Z. Also provided is manufacturing method for a circuit substrate.