Reduction/oxidation reagents have been found to be effective to chemically cure a sparse metal nanowire film into a fused metal nanostructured network through evidently a ripening type process. The resulting fused network can provide desirable low sheet resistances while maintaining good optical transparency. The transparent conductive films can be effectively applied as a single conductive ink or through sequential forming of a metal nanowire film with the subsequent addition of a fusing agent. The fused metal nanowire films can be effectively patterned, and the patterned films can be useful in devices, such as touch sensors.

A process for depositing a metal on a substrate involves the use of two reduction reactions in a bottom-up based tandem manner starting from a substrate surface and working upward. A first reduction reaction starts on the substrate surface at ambient temperature, and a second reduction reaction, which is initiated by the reaction heat of the first reduction reaction, occurs in a reactive ink solution film coated on top, which becomes solid after the reaction. Gas and other small molecules generated from the reduction reactions, and the solvent, can readily escape through the upper surface of the film before the solid metal layer is formed or during post-treatment, with no or few voids left in the metal film. Thus, the process can be used to form highly conductive films and features at ambient temperature on various substrates.

A precursor article has a substrate and a photosensitive thin film or a photosensitive thin film pattern on a supporting side. The photosensitive thin film and each photosensitive thin film patterns comprises a non-hydroxylic-solvent soluble silver complex that is represented by the following formula (I):

(Ag.sup.+).sub.a(L).sub.b(P).sub.c (I) wherein L represents an -oxy carboxylate; P represents an oxime compound; a is 1 or 2; b is 1 or 2; and c is 1, 2, 3, or 4, provided that when a is 1, b is 1, and when a is 2, b is 2. A photosensitizer that can either reduce the reducible silver ion or oxidize the -oxy carboxylate having a reduction potential can also be present. Such precursor articles can be irradiated with UV-visible radiation to reduce the silver ions to provide electrically-conductive metallic silver in thin films or thin film patterns in product articles or devices.

A substrate for a printed circuit board according to an embodiment of the present invention includes a base film having an insulating property, and a conductive layer formed on at least one of surfaces of the base film. In the substrate for a printed circuit board, at least the conductive layer contains titanium in a dispersed manner. The conductive layer preferably contains copper or a copper alloy as a main component. A mass ratio of titanium in the conductive layer is preferably 10 ppm or more and 1,000 ppm or less. The conductive layer is preferably formed by application and heating of a conductive ink containing metal particles. The conductive ink preferably contains titanium or a titanium ion. The metal particles are preferably obtained by a titanium redox process including reducing metal ions using trivalent titanium ions as a reducing agent in an aqueous solution by an action of the reducing agent.

In a conductive film forming method using photo sintering, a conductive film having low electric resistance is easily formed. Disclosed is a conductive film forming method in which a conductive film is formed using a photo sintering, which includes the steps of: forming a liquid film made of a copper particulate dispersion on a substrate, drying the liquid film to form a copper particulate layer, subjecting the copper particulate layer to photo sintering to form a conductive film, attaching a sintering promoter to the conductive film, and further subjecting the conductive film having the sintering promoter attached to photo sintering. The sintering promoter is a compound which removes copper oxide from metallic copper. Thereby, the sintering promoter removes a surface oxide film of copper particulates in the conductive film.

A precursor article has a substrate and a photosensitive thin film or a photosensitive thin film pattern on a supporting side. The photosensitive thin film and each photosensitive thin film patterns comprises a non-hydroxylic-solvent soluble silver complex that is represented by the following formula (I):

(Ag.sup.+).sub.a(L).sub.b(P).sub.c (I)

wherein L represents an -oxy carboxylate; P represents a 5- or 6-membered N-heteroaromatic compound; a is 1 or 2; b is 1 or 2; and c is 1, 2, 3, or 4, provided that when a is 1, b is 1, and when a is 2, b is 2. A photosensitizer that can either reduce the reducible silver ion or oxidize the -oxy carboxylate having a reduction potential can also be present. Such precursor articles can be irradiated with UV-visible radiation to reduce the silver ions to provide electrically-conductive metallic silver in thin films or thin film patterns in product articles or devices.

An electroconductive-film-forming composition capable of forming an electroconductive film having excellent conductivity and few voids and a method for producing an electroconductive film using the same. The electroconductive-film-forming composition contains copper particles having an average particle diameter of 1 nm to 10 m, copper oxide particles having an average particle diameter of 1 nm to 500 nm, a reducing agent having a hydroxy group, a metal catalyst including metals other than copper, and a solvent, in which the content of the copper oxide particles is 50% by mass to 300% by mass with respect to the content of the copper particles, the content of the reducing agent is 100 mol % to 800 mol % with respect to the content of the copper oxide particles, and the content of the metal catalyst is 10% by mass or less with respect to the content of the copper oxide particles.

Embodiments of the present invention relates generally to the manufacture of printed circuit boards (PCB's) or printed wiring boards (PWB's), and particularly to methods for treating smooth copper surfaces to increase the adhesion between a copper surface and an organic substrate. More particularly, embodiments of the present invention related to methods of achieving improved bonding strength of PCBs without roughening the topography of the copper surface. The bonding interface between the treated copper and the resin layer of the PCB exhibits excellent resistance to heat, moisture, and chemicals involved in post-lamination process steps.

Pyrimidine derivatives which contain one or more electron donating groups on the ring are used as catalytic metal complexing agents in aqueous alkaline environments to catalyze electroless metal plating on metal clad and un-clad substrates. The catalysts are monomers and free of tin and antioxidants.

The invention provides a composition set comprising: a conductor layer-forming composition comprising a dispersing medium and inorganic particles comprising a metallic oxide; and a conductive adhesive composition comprising a binder and conductive particles having a number average particle size of from 1 nm to 3000 nm.