A protection tape for a printed circuit board (PCB) includes an insulating base plate, a conductive layer over the insulating base plate, and an adhesive layer over the conductive layer, the adhesive layer including a main part having a first thickness and a subsidiary part having a second thickness less than the first thickness, the main part corresponding to at least a center portion of the insulating base plate and the subsidiary part being arranged at an outside of the main part.

In a built-in coil substrate, coil conductor patterns are provided on insulating base materials. Coil interlayer connection conductors, which provide interlayer connection between the coil conductor patterns, are provided on the insulating base materials and made of conductive paste. First and second external electrodes are provided on a first principal surface of a multilayer body. One of the coil conductor patterns is connected to the first external electrode by first-external-electrode connection conductors made of the conductive paste. Another one of the coil conductor patterns is connected to the second external electrode by a second-external-electrode connection conductor. The second-external-electrode connection conductor is a metal film provided in a through hole that extends through the multilayer body in a stacking direction in which the insulating base materials are stacked.

Disclosed is a flexible copper clad laminate including a first copper foil layer, a composite layer, and a second copper foil layer. Preferably, the composite layer includes a polyimide layer and a plurality of thermoplastic polyimide layers as an outermost layer thereof being the thermoplastic polyimide layers. In particular, with respect to a total thickness of the composite layer, a total thickness of the plurality of thermoplastic polyimide layers is in a range of from about 15 to about 50%, and a total thickness of the polyimide layer is in a range of from about 50 to about 85%. Each thickness of the first copper foil layer and the second copper foil layer is in a range of from about 30 to about 80 μm, and the total thickness of the composite layer is in a range of from about 40 to about 60 μm.

A high-frequency signal transmission line includes a body including a plurality of first base layers and a second base layer stacked on one another in a stacking direction. The first base layers have a first relative permeability, and the second base layer has a relative permeability lower than the first relative permeability. A first signal line and a second signal line extending along the first signal line are provided in the body. In a cross section perpendicular or substantially perpendicular to a first direction in which the first signal line extends, the second base layer occupies at least a portion of an area between the first signal line and the second signal line. In the cross section perpendicular or substantially perpendicular to the first direction, the plurality of first base layers define a loop enclosing the first signal line, the second signal line and the second base layer.

A flexible printed circuit board having at least a set of strip line transmission path by being provided with a signal line, and a pair of ground layers and, includes a pleated part PL having a plurality of curved portions which are curved so as to be opened or closed, in which in the ground layers, mesh ground layers in which conductive portions are provided in a mesh shape, and solid ground layers in which the conductive portions are provided in a planar state, are provided, in which the mesh ground layers are arranged on an outer peripheral side of the curved portions PL2, and the solid ground layers are arranged on an inner peripheral side of the curved portions.

The present invention relates to a composition for forming a conductive pattern and a resin structure having a conductive pattern, wherein the composition makes it possible to form a fine conducive pattern on various polymer resin products or resin layers through a simple process, and can more effectively meet needs of the art, such as displaying various colors.

Provided are circuit board excellent in interlayer adhesion and solder heat resistance, and production method thereof. The circuit board is produced by a method including: preparing a plurality of at least one kind of thermoplastic liquid crystal polymer (TLCP) films, forming a conductor layer on one side or both sides of a film in at least one of the films to obtain a unit circuit board, laminating the films containing the unit circuit board to obtain a stacked material, conducting thermo-compression-bonding of the stacked material under pressurization to a first temperature giving an interlayer adhesion to integrate the stacked material, carrying out structure-controlling thermal treatment by heating the integrated stacked material at a second temperature which is lower than the first temperature and is lower than a melting point of a TLCP having a lowest melting point out of the plurality of TLCP films.

A laminated uncured sheet of the present disclosure has a structure in which resin sheet layers and resin layers are alternately laminated and a through hole penetrating in the laminating direction is formed, wherein the resin sheet layers are formed with a thermosetting resin composition containing a thermosetting resin as a main component, the resin layers are formed with a thermoplastic resin composition containing a thermoplastic resin, and the thermoplastic resin composition is adhered to the inner wall surface of the resin sheet layer part in the through hole.

A method for manufacturing a circuit board (100) includes: providing a first single-sided circuit substrate (20) including an insulating base layer (11) and a circuit layer (13); forming first conductive posts (111) electrically connected to the circuit layer (13) in the insulating base layer (11) to obtain a second single-sided circuit substrate (13); providing a first adhesive layer (40), forming second conductive posts (401); providing one second single-sided circuit substrate (30), defining a receiving groove (31) to obtain a third single-sided circuit substrate (50); providing another first single-sided circuit substrate (20), mounting an electronic component (14) on the circuit layer (13) to obtain a surface mounted circuit substrate (60); stacking the first single-sided circuit substrate (20), the first adhesive layer (40), the second single-sided circuit substrate (30), at least one of the third single-sided circuit substrate (50), and the surface mounted circuit substrate (60) in that order; pressing the intermediate body (70).

To provide a copper-clad laminate which maintains adhesion between a resin film and a conductor layer and which suppresses the occurrence of wrinkles. A copper-clad laminate has a base film containing a thermoplastic resin, an underlying metal layer film-formed on a surface of the base film by a dry plating method, and a copper layer film-formed on a surface of the underlying metal layer. The underlying metal layer has a mean thickness of 0.3 to 1.9 nm. Since the underlying metal layer has a mean thickness of 0.3 nm or more, it is possible to maintain adhesion between the base film and a conductor layer. Since the underlying metal layer has a mean thickness of 1.9 nm or less, it is possible to suppress an increase in the temperature of a film during film-forming of the underlying metal layer, and it is possible to suppress the occurrence of wrinkles.