Abstract: After disposing metallic foils on either surface of a prepreg sheet of low compressibility having conducting holes filled with conductive paste, the prepreg sheet is compressed in a state of being kept at a relatively low temperature, and after that, the temperature is raised under pressure to melt and harden the resin in the prepreg sheet, and thereby, the connecting resistance is stabilized, and a high-quality circuit board can be obtained.

Abstract: A circuit board with reliable electrical connections is provided. An insulated board material, having connections for connecting a layer to another layer, includes a reinforcing member. A thickness of the entire insulated board material is at least equal to and not more than 1.5 times of a thickness of the reinforcing member.

Abstract: In a heat and press stage of manufacturing printed wiring boards, a functional surface layer having release property is provided on a surface of a cushion, and a blocking layer is prepared between the functional surface layer and an inner layer having cushion property so that a frequency of use of the cushion can be increased.

Abstract: After disposing metallic foils on either surface of a prepreg sheet of low compressibility having conducting holes filled with conductive paste, the prepreg sheet is compressed in a state of being kept at a relatively low temperature, and after that, the temperature is raised under pressure to melt and harden the resin in the prepreg sheet, and thereby, the connecting resistance is stabilized, and a high-quality circuit board can be obtained.

Abstract: After disposing metallic foils on either surface of a prepreg sheet of low compressibility having conducting holes filled with conductive paste, the prepreg sheet is compressed in a state of being kept at a relatively low temperature, and after that, the temperature is raised under pressure to melt and harden the resin in the prepreg sheet, and thereby, the connecting resistance is stabilized, and a high-quality circuit board can be obtained.

Abstract: After disposing metallic foils on either surface of a prepreg sheet of low compressibility having conducting holes filled with conductive paste, the prepreg sheet is compressed in a state of being kept at a relatively low temperature, and after that, the temperature is raised under pressure to melt and harden the resin in the prepreg sheet, and thereby, the connecting resistance is stabilized, and a high-quality circuit board can be obtained.

Abstract: In a heat and press stage of manufacturing printed wiring boards, a functional surface layer having release property is provided on a surface of a cushion, and a blocking layer is prepared between the functional surface layer and an inner layer having cushion property so that a frequency of use of the cushion can be increased.

Abstract: A circuit board ensuring electrical connections is provided. An insulated board material, having connecting means for connecting a layer to another layer, includes a reinforcing member. A thickness of the entire insulated board material is at least equal to or not more than 1.5 times of a thickness of the reinforcing member.

Abstract: A method of manufacturing circuit board comprising: holding a laminate with metal foil or resin-coated metal foil disposed on both surfaces or on one surface of board material or board material with metal foil circuit formed thereon between metal plates, and applying at least one of heat and pressure to the laminate. A hard coat layer formed on both surfaces or on one surface of the metal plate protects the metal plate. Accordingly, the metal plate is hardly scratched by its contact with the conveyor and the like or by handling by the operator during the production of the circuit boards. Further, since the hard coat layer surface is smoothly finished, resin or contamination sticking to the metal plate can be easily removed, thereby prolonging the life of the metal plate. As a result, it is possible to produce high-quality circuit boards at low costs.