Abstract: Protective film-laminated adhesive sheets which include; an adhesive sheet including a support having first and second surfaces and a resin composition layer in contact with the second surface of the support; and a protective film having first and second surfaces with the second surface of the protective film in contact with the resin composition layer of the adhesive sheet and in which the first surface of the protective film has an arithmetic mean roughness (Rap1) of 100 nm or more, and the second surface of the protective film has an arithmetic mean roughness (Rap2) of 100 nm or more are capable of suppressing a winding displacement when the sheet is wound into a roll and are capable of preventing a resin separation when the protective film is peeled off in an automatic cutter device.

Abstract: Multilayer printed wiring boards may be prepared by forming a via hole by laser irradiation in insulating layer formed by a prepreg, comprised of a glass cloth impregnated with a thermosetting resin composition, and subjecting the via hole to a glass etching treatment with a glass etching solution and then to a desmear treatment with an oxidizing agent solution. By such a process, etch back phenomenon and excessive protrusion of glass cloth from the wall surface of a via hole can be sufficiently suppressed, and a highly reliable via can be formed. Particularly, a highly reliable via can be formed in a small via hole having a top diameter of 75 ?m or below.

Abstract: Multi-layer printed wiring boards may be produced by: (1) conveying an adhesive sheet from an adhesive sheet roll wherein an adhesive sheet having a prepreg formed on a support film is wound in a roll and placing the adhesive sheet such that a prepreg surface contacts one or both of the surfaces of a circuit board, (2) partially adhering the adhesive sheet to the circuit board by heating and pressing a part of the adhesive sheet from the support film side, and cutting the adhesive sheet according to the size of the circuit board with a cutter, (3) heating and pressing the temporarily fitted adhesive sheet under reduced pressure to laminate the adhesive sheet on the circuit board, (4) forming an insulating layer by thermally curing the prepreg, and (5) detaching the support film after the thermal curing step.

Abstract: Multilayer printed wiring boards may be prepared by forming a via hole by laser irradiation in insulating layer formed by a prepreg, comprised of a glass cloth impregnated with a thermosetting resin composition, and subjecting the via hole to a glass etching treatment with a glass etching solution and then to a desmear treatment with an oxidizing agent solution. By such a process, etch back phenomenon and excessive protrusion of glass cloth from the wall surface of a via hole can be sufficiently suppressed, and a highly reliable via can be formed. Particularly, a highly reliable via can be formed in a small via hole having a top diameter of 75 ?m or below.

Abstract: Multilayer printed wiring boards may be prepared by forming a via hole by laser irradiation in insulating layer formed by a prepreg, comprised of a glass cloth impregnated with a thermosetting resin composition, and subjecting the via hole to a glass etching treatment with a glass etching solution and then to a desmear treatment with an oxidizing agent solution. By such a process, etch back phenomenon and excessive protrusion of glass cloth from the wall surface of a via hole can be sufficiently suppressed, and a highly reliable via can be formed. Particularly, a highly reliable via can be formed in a small via hole having a top diameter of 75 ?m or below.

Abstract: Multi-layer printed wiring boards may be produced by: (1) conveying an adhesive sheet from an adhesive sheet roll wherein an adhesive sheet having a prepreg formed on a support film is wound in a roll and placing the adhesive sheet such that a prepreg surface contacts one or both of the surfaces of a circuit board, (2) partially adhering the adhesive sheet to the circuit board by heating and pressing a part of the adhesive sheet from the support film side, and cutting the adhesive sheet according to the size of the circuit board with a cutter, (3) heating and pressing the temporarily fitted adhesive sheet under reduced pressure to laminate the adhesive sheet on the circuit board, (4) forming an insulating layer by thermally curing the prepreg, and (5) detaching the support film after the thermal curing step.

Abstract: A production method of a multi-layer printed wiring board containing the following steps (1)-(5): (1) a temporary fitting preparatory step including conveying an adhesive sheet from an adhesive sheet roll wherein an adhesive sheet having a prepreg formed on a support film is wound in a roll and placing the adhesive sheet such that a prepreg surface contacts one or both of the surfaces of a circuit board, (2) a temporary fitting step for temporarily fitting the adhesive sheet to the circuit board, including partially adhering the adhesive sheet to the circuit board by heating and pressing a part of the adhesive sheet from the support film side, and cutting the adhesive sheet according to the size of the circuit board with a cutter, (3) a laminating step including heating and pressing the temporarily fitted adhesive sheet under reduced pressure to laminate the adhesive sheet on the circuit board, (4) a thermal curing step including forming an insulating layer by thermally curing the prepreg, and (5) a detachin

Abstract: A production method of a multi-layer printed wiring board containing the following steps (1)-(5): (1) a temporary fitting preparatory step including conveying an adhesive sheet from an adhesive sheet roll wherein an adhesive sheet having a prepreg formed on a support film is wound in a roll and placing the adhesive sheet such that a prepreg surface contacts one or both of the surfaces of a circuit board, (2) a temporary fitting step for temporarily fitting the adhesive sheet to the circuit board, including partially adhering the adhesive sheet to the circuit board by heating and pressing a part of the adhesive sheet from the support film side, and cutting the adhesive sheet according to the size of the circuit board with a cutter, (3) a laminating step including heating and pressing the temporarily fitted adhesive sheet under reduced pressure to laminate the adhesive sheet on the circuit board, (4) a thermal curing step including forming an insulating layer by thermally curing the prepreg, and (5) a detachin

Abstract: Multilayer printed wiring boards may be prepared by forming a via hole by laser irradiation in insulating layer formed by a prepreg, comprised of a glass cloth impregnated with a thermosetting resin composition, and subjecting the via hole to a glass etching treatment with a glass etching solution and then to a desmear treatment with an oxidizing agent solution. By such a process, etch back phenomenon and excessive protrusion of glass cloth from the wall surface of a via hole can be sufficiently suppressed, and a highly reliable via can be formed. Particularly, a highly reliable via can be formed in a small via hole having a top diameter of 75 ?m or below.