Abstract: In conducting wiring by masking the portion other than the portion to be wired of a metallic laminate with a photoresist for plating and subjecting only the portion to be wired to pattern plating, the provision of a noble metal layer made of gold, platinum or the like, or a metallic layer made of a metal having a larger ionization tendency than that of a metal used in the pattern plating on the metallic layer constituting the undercoat of the photoresist for plating enables the peeling of the resist for plating to be prevented and excellent fine wiring to be conducted.

Abstract: A method for treating the interior surfaces of holes as well as the surfaces of a perforated workpiece by dipping it into treating liquid includes a step of causing treating liquid to flow at both ends of the holes in a direction perpendicular to these holes at different velocities. In order to create these liquid flows at different velocities, the workpiece is dipped in the liquid so that the holes extend substantially horizontally, and air bubble jets are alternately delivered along both ends of the holes, or fins are provided at locations adjacent both ends of the holes so as to extend outwardly upwardly at one side of the hole ends and extend outwardly downwardly at the other side of the hole ends, and these fins are moved upwardly and downwardly.

Abstract: The present invention provide a process for producing printed circuit boards which comprises the steps of(a) roughening a surface of a copper layer formed on an insulating board.(b) coating the roughened surface of copper layer with a photo-resist layer containing a sublimable copper-corrosion inhibitor, exposing the resist layer selectively to actinic rays according to a circuit pattern to form, and developing the resulting resist layer, thereby forming plating-resist coats on circuit-negative pattern portions of the copper layer,(c) heat-treating the plating-resist coats,(d) plating chemically the circuit-corresponding portion with copper,(e) removing the plating-resist coats, and(f) removing the copper layer except the circuit-corresponding portion thereof.

Abstract: An electroless copper plating process for producing fine patterned wiring boards is improved by supplying very fine oxygen-containing gas bubbles through a porous alkali-resistant resin gas dispersing tube. An electroless copper plating apparatus having such a gas dispersing tube is also provided.

Abstract: A pretreatment process for removing air within through-holes of printed circuit boards before plating the through-holes is provided. Air within the through-holes of the printed circuit boards is replaced with a saturated vapor of a water-soluble liquid by dipping the printed circuit board into the boiled liquid and then the saturated vapor is dissolved in water or a water-soluble liquid to remove air.

Abstract: A method of bonding copper and a resin together is disclosed which comprises forming a copper oxide layer on the surface of copper to be bonded to a resin, reducing the copper oxide layer to metallic copper with a reducing solution, and bonding the metallic copper and the resin together. According to this method, a good acid resistance of the bonding interface and a sufficiently high bonding strength can be obtained.