Abstract: The present invention provides a titanium copper alloy excellent in strength, electrical conductivity and bendability, characterized in that it consists essentially of 1.5 to 2.3% by mass of Ti, balance Cu and inevitable impurities; said alloy having a 0.2% yield strength of 750 MPa or greater; an electrical conductivity of 17% IACS or greater; and a relationship represented by the formula: MBR/t?0.04×YS?30, in which, YS is a 0.2% yield strength (MPa), and MBR/t is a ratio of a minimum bending radius (MBR; mm) for no cracking when said alloy is subjected to W bend test according to JIS H3130 standard along a transverse direction to a rolling direction, to a thickness (t; mm) of test piece.

Abstract: For a three-layer flexible board, there is provided a copper alloy foil that requires no roughening processing, that has good adhesion with an adhesive containing an epoxy resin, that can be laminated to form a copper-clad laminate, that has a low surface roughness, and that has high conductivity and strength. The copper alloy of the foil contains at least one of 0.01-2.0 weight percent Cr and 0.01-1.0 weight percent Zr or contains 1.0-4.8 weight percent Ni and 0.2-1.4 weight percent Si. Good adhesion of the copper alloy foil to a resin substrate with an adhesive containing an epoxy resin is obtained by setting the thickness of the anticorrosive coating to less than 3 nm; the surface roughness of the copper alloy foil is below 2 ?m expressed as ten-point average surface roughness (Rz); and, without roughening processing, the 180° C. peel strength, after adhesion of the copper alloy foil to the board film by means of an adhesive containing an epoxy resin, is greater than 8.0 N/cm.

Abstract: The present invention provides a Cu—Cr—Zr alloy material excellent in fatigue and intermediate temperature characteristics, which comprises 0.05 to 1.0% by mass of Cr and 0.05 to 0.25% by mass of Zr with a balance of Cu and inevitable impurities. The alloy comprises inclusion particles based on any one of Zr and a Cu—Zr alloy having a diameter of 0.1 ?m or more, and the proportion of the inclusion particles containing 10% or more of sulfur as one of the inevitable impurities is one particle/mm2.

Abstract: Copper alloys having excellent strength while suppressing irregularity of wavelengths, etc., of the fluctuations and having excellent bendability are obtained while suppressing growth of crystal grains. The copper-based alloy contains 2.0 to 4.0 mass % of Ti, and the total content of unavoidable impurity elements Pb, Sn, Zn, Mn, Fe, Co, Ni, S, Si, Al, P, As, Se, Te, Sb, Bi, Au, and Ag is not more than 0.1 mass %, and contents of each element thereof is not more than 0.01 mass %, and not less than 80% of quality of a second-phase particles having an area of not less than 0.01 &mgr;m2 observed by a cross section speculum contains not less than 3% of the total amount of the above described unavoidable impurity elements in composition.

Abstract: For a two-layer printed wiring board including a polyimide substrate produced with varnish containing polyamic acid as the raw material for the polyimide and a copper alloy foil laminated with the polyimide substrate, there is provided, for the copper alloy foil, a copper alloy containing, in addition to copper and unavoidable impurities, either (1) 0.02 to 1.0 weight percent Ag and/or 0.01 to 0.5 weight percent In or (2) alloy composition (1) plus a total of 0.005 to 2.5 weight percent of at least one of the additional elements Al, Be, Co, Fe, Mg, Mn, Ni, P, Pb, Si, Ti and Zn, or (3) 0.001 to 0.5 weight percent Sn or (4) alloy composition (3) plus a total of 0.005 to 2.5 weight percent of at least one of the additional elements of alloy composition (2) and each of (1), (2), (3) and (4) preferably having a heat resistance of at least 300° C.

Abstract: Superior bendability in a copper alloy and further strength improvement ensures characteristics which are sufficiently superior in view of essential qualities of strength of titanium-copper. 2.0 to 4.0 mass % of Ti, 0.01 to 0.50 mass % of one or more than one kind of element from among Fe, Co, Ni, Cr, V, Zr, B, and P as the third element group are contained, and not less than 50% of the total content of these elements is made to exist as second-phase particles.