Abstract: A wired circuit board having improved adhesion between the conductive pattern and an insulating layer to prevent a plating solution from remaining between a metal plating layer and the insulating layer. The invention prevents ionic impurities in the plating solution from remaining as residual or ionic contamination, thereby preventing a short circuit from developing when electric current flows through the circuit under a high temperature and high humidity environment. Lower end portions of the terminal portions that are formed on an insulating base layer and lower end portions of side surfaces and metal plating layers that cover the terminal portions are embedded in the insulating base layer in a flexible wired circuit board.

Abstract: A combined metal layer and a protective film are arranged on one surface side of an insulating layer, and a combined metal layer and a protective film are arranged on the other surface side of the insulating layer. These layers are overlapped one another to be passed between a pair of laminating rollers. In this case, a temperature with which the combined metal layers are heated by the laminating rollers is adjusted to not less than 300° C. and not more than 360° C. A time period during which the combined metal layers are heated by the laminating rollers is adjusted to not less than 0.1 second and not more than 0.8 second.

Abstract: A wired circuit board having improved adhesion between the conductive pattern and an insulating layer to prevent a plating solution from remaining between a metal plating layer and the insulating layer. The invention prevents ionic impurities in the plating solution from remaining as residual or ionic contamination, thereby preventing a short circuit from developing when electric current flows through the circuit under a high temperature and high humidity environment. Lower end portions of the terminal portions that are formed on an insulating base layer and lower end portions of side surfaces and metal plating layers that cover the terminal portions are embedded in the insulating base layer in a flexible wired circuit board.

Abstract: A wired circuit board having improved adhesion between the conductive pattern and an insulating layer to prevent a plating solution from remaining between a metal plating layer and the insulating layer. The invention prevents ionic impurities in the plating solution from remaining as residual or ionic contamination, thereby preventing a short circuit from developing when electric current flows through the circuit under a high temperature and high humidity environment. Lower end portions of the terminal portions that are formed on an insulating base layer and lower end portions of side surfaces and metal plating layers that cover the terminal portions are embedded in the insulating base layer in a flexible wired circuit board.

Abstract: A printed circuit board base sheet is manufactured by laminating an insulating resin film and a metal foil using a laminate roller. A rustproofing layer containing chromium is formed on a surface of the metal foil. The temperature of the laminate roller is set to 330 to 390° C. A time period during which the metal foil and the laminate roller are brought into contact with each other immediately before a contact time point between the insulating resin film and the metal foil is set to 0.5 to 4.0 seconds.

Abstract: The invention provides a process for producing a substrate for flexible circuit boards which comprises: providing a multilayered insulating resin layer comprising an insulating layer and an adhesive layer; and laminating a metal foil to the insulating layer of the multilayered insulating resin layer via the adhesive layer at a temperature not lower than the glass transition temperature of the insulating layer.

Abstract: A ground wiring layer and a signal wiring layer are formed on a base insulating layer. A cover insulating layer is formed on the base insulating layer with an adhesive layer therebetween to cover the ground wiring layer and the signal wiring layer except for a certain region on the ground wiring layer. An electromagnetic shield layer is formed on the certain region of the ground wiring layer and the cover insulating layer. A resin solution is applied on a release sheet and dried, so that a transfer sheet including the resin layer and the release sheet is formed. Then, the surface of the resin layer is placed on the top surface of the electromagnetic shield layer and these layers are heated and pressurized, so that the transfer sheet is laminated on the electromagnetic shield layer. Thereafter, the release sheet is removed.

Abstract: A wired circuit board having good alkali resistance as well as good flexibility. The wired circuit board comprising an insulating base layer 21, a conductor layer 22 laminated on the insulating layer 21, and an insulating cover layer 23 formed on the insulating base layer 21 to cover the conductor layer 22, wherein at least the insulating base layer 21 is formed from a resin having a repeated unit expressed by at least either the following general formula (1) or (2), and a weight-average molecular weight in the range of 0.1×105 to 1.

Abstract: A wired circuit board which even when a conductive pattern is formed in the form of fine pitch can provide improved adhesion between the conductive pattern and an insulating layer to prevent a plating solution from remaining between a metal plating layer and the insulating layer, so as to prevent ionic impurities in the plating solution from remaining as residual or ionic contamination, whereby even when electric current flows through the circuit under a high temperature and high humidity environment over a long term, a short circuit from ionic migration can be prevented to suppress insulating failure. Lower end portions of terminal portions 5 formed on an insulating base layer 2 and lower end portions of side surfaces and metal plating layers 6 covering over the terminal portions 5 are embedded in the insulating base layer 2 in a flexible wired circuit board 1 at one longitudinal end portion thereof exposed from an insulating cover layer 4.

Abstract: The invention provides a process for producing a substrate for flexible circuit boards which comprises: providing a multilayered insulating resin layer comprising an insulating layer and an adhesive layer; and laminating a metal foil to the insulating layer of the multilayered insulating resin layer via the adhesive layer at a temperature not lower than the glass transition temperature of the insulating layer.

Abstract: A flexible printed circuit board with a reinforcing plate, which comprises: a flexible printed circuit board including i) a conductive circuit pattern layer, and ii) an insulating layer made of a plastic film; a reinforcing plate; and an adhesive layer so that the reinforcing plate is attached to the flexible printed circuit board via the adhesive layer, wherein the adhesive layer is formed from an adhesive composition containing a composite metal hydroxide represented by formula (1): M1-xQx(OH)2  (1) wherein M is at least one metal atom selected from the group consisting of Mg, Ca, Sn and Ti; Q is at least one metal atom selected from the group consisting of Mn, Fe, Co, Ni, Cu and Zn; and x is a positive number from 0.01 to 0.5.

Abstract: A flexible printed circuit board with a reinforcing plate, which comprises: a flexible printed circuit board including i) a conductive circuit pattern layer, and ii) an insulating layer made of a plastic film; a reinforcing plate; and an adhesive layer so that the reinforcing plate is attached to the flexible printed circuit board via the adhesive layer, wherein the adhesive layer is formed from an adhesive composition containing a composite metal hydroxide represented by formula (1):

Abstract: A flexible wiring board which exhibits a sufficient flex life under high temperature working conditions. The flexible wiring board comprises an insulation layer provided on both surfaces of a conductor layer, optionally with an adhesive layer provided interposed therebetween, wherein the layers being in direct contact with both surfaces of the conductor layer exhibit an average complex shear modulus value of from 1.0×1010 to 4×1010 dyn/cm2 at a temperature of 60° C. and a frequency of 25 Hz.

Abstract: After a flexible printed circuit is left under an atmosphere of a water vapor pressure of not lower than 30 mmHg so as to absorb moisture, a voltage is applied between two wiring portions to thereby measure an insulation resistance value between the wiring portions during the voltage application. The quantity &Dgr;log(R) of the change of the insulation resistance value at regular intervals is obtained. An examination is made as to whether the maximum of the quantity &Dgr;log(R) of the change of the insulation resistance value is not larger than a predetermined reference value or not. From this examination, a judgment is made as to whether the flexible printed circuit is good or not.

Abstract: The present invention provides a rigid circuit member obtained by bending a composite laminate comprising a circuit conductor made of a metal foil interposed between plastic films having an elastic modulus of not less than 450 kg/mm2 with an adhesive, characterized in that as said plastic film there is used a polyethylene naphthalate film. The present invention also provides a circuit board adapted to be connected to a conductor on a rigid substrate, characterized in that said circuit conductor is interposed between polyethylene naphthalate films. The present invention further provides a printed circuit board, comprising a polyethylene naphthalate film having an elastic modulus of not less than 500 kg/mm2, not more than 1.5×10−5/° C., a hygroscopic expansion coefficient of not more than 1.2×10−5/%RH, a water vapor permeability of not more than 15 g/m2/mil day, a percent water absorption of not more than 2% and a melting point of not higher than 280° C.

Abstract: A polyester film for printed circuits to be used as a base in a printed circuit base plate or as a base and/or cover layer in a printed circuit board, which undergoes a degree of dimensional stability of not more than 1% in both the longitudinal and transverse directions when kept at 150.degree. C. for 30 minutes, and which is obtained by heat treating an extrusion molded and stretched polyester film at 150.degree. C. to 240.degree. C. without applying tension.

Abstract: In a printed circuit substrate incorporating a resistor pattern film and a conductor pattern film are formed on the two surfaces of a high conductive material layer such as a copper foil, respectively, in a predetermined positional relationship, and an insulating support is combined directly or indirectly with the resistor pattern film on the high conductive material layer, whereby a printed circuit board with resistance elements having high performance can be manufactured, while the number of processing steps can be greatly reduced.

Abstract: A printed circuit substrate with a resistance coat comprises an insulating support having provided at least on the one side thereof a highly conductive material layer interposed with a resistance coat. The resistance coat comprises tin-nickel alloy.

Abstract: In a printed circuit substrate incorporating a resistor pattern film and a conductor pattern film are formed on the two surfaces of a high conductive material layer such as a copper foil, respectively, in a predetermined positional relationship, and an insulating support is combined directly or indirectly with the resistor pattern film on the high conductive material layer, whereby a printed circuit board with resistance elements having high performance can be manufactured, while the number of processing steps can be greatly reduced.