The present invention uses a flux containing a rosin, a solvent, a thixo agent, and an activator. The thixo agent contains a polyamide and a compound represented by general formula (1). The polyamide is a condensate between an amine and at least one selected from aliphatic carboxylic acids and hydroxy group-containing aliphatic carboxylic acids, and has an endothermic peak at a temperature of 120-200° C. In the general formula, R.sup.11 represents a hydrocarbon group having 11-30 carbon atoms. R.sup.0a represents a hydrogen atom or a hydrocarbon group having 12-31 carbon atoms. R.sup.0b represents an n-valent hydrocarbon group having 4-12 carbon atoms. R.sup.21 represents an alkylene group having 2-6 carbon atoms. R.sup.0c represents a single bond or an alkylene group having 2-6 carbon atoms. n represents 1 or 2. When n represents 1, m represents an integer of 1-3. When n represents 2, m represents 1.

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A conductive paste and method of manufacturing thereof. The conductive paste comprises conductive particles dispersed in an organic medium, the organic medium comprising: (a) a solvent; and (b) a binder comprising a polyester. The conductive paste typically comprises silver and may contain various other additives. A stretchable conductive layer can be formed by curing the conductive paste.

A ceramic-copper composite having a flat plate shape, including: a ceramic layer; a copper layer; and a brazing material layer present between the ceramic layer and the copper layer, in which a specified Expression (1) is satisfied in a cut surface of the copper layer obtained when the ceramic-copper composite is cut at a plane perpendicular to a main surface of the ceramic-copper composite, where S(102)% is an area ratio occupied by copper crystals having a crystal orientation of which an inclination from a crystal orientation of (102) plane is within 10°, S(101)% is an area ratio occupied by copper crystals having a crystal orientation of which an inclination from a crystal orientation of (101) plane is within 10°, S(111)% is an area ratio occupied by copper crystals having a crystal orientation of which an inclination from a crystal orientation of (111) plane is within 10°, and S(112)% is an area ratio occupied by copper crystals having a crystal orientation of which an inclination from a crystal orientation of (112) plane is within 10°.

Provided are a flux composition that is applicable without any film formation step, and solder paste, a solder joint and a solder joining method using the flux composition. The flux composition contains 20 wt % or more and 50 wt % or less of an epoxy resin, 15 wt % or more and 45 wt % or less of diallyl bisphenol A, and 1 wt % or more and 30 wt % or less of organic acid.

A solder alloy is provided which can withstand the severe characteristics of a temperature cycle between a low temperature of −40° C. and a high temperature of 125° C., withstand an external force applied due to, for example, riding on a curb or collision with a vehicle ahead for a long period of time, and can suppress change in viscosity of a solder paste over time. In addition, a solder paste, a solder ball, and a solder preform in which the solder alloy is used; a solder joint formed through the use thereof; and an on-board electronic circuit, an ECU electronic circuit, an on-board electronic circuit device, and an ECU electronic circuit device which include this solder joint are provided. The solder alloy contains, by mass %, 1% to 4% of Ag, 0.5% to 1.0% of Cu, 1.5% to 5.5% of Bi, 1.0% to 5.3% of Sb (or greater than 5.5% and less than or equal to 7.0% of Bi and 2.0% to 5.3% of Sb), 0.01% to 0.2% of Ni, 0.0040% to 0.0250% of As, and a balance of Sn.

The disclosure relates to a reversible adhesive composition including a copolymer between a vinyl spacer monomer unit and a vinyl reversible binder monomer unit. Each monomer unit can be based on acrylate monomer, a vinyl ester monomer, or a vinyl ether monomer, with the spacer monomer unit generally having a shorter pendant chain (such as 1-3 carbon atoms) and the reversible binder monomer unit having a longer pendant chain (such as 3-20 carbon atoms). A corresponding article includes first and second surfaces (or substrates) that are in contact with and bonded to the reversible adhesive composition at an interface therebetween. The reversible adhesive composition generally involves non-covalent and/or non-ionic bonding forces, for example H-bonding, permanent dipole, electron donor-acceptor moieties, and/or van der Waals forces, between the copolymer chains. The first and second surfaces can be repeatedly bonded, separated, and re-bonded while retaining the adhesive strength of the reversible adhesive composition.

A resin composition for soldiering is provided. The resin composition includes 1 wt % or more and 40 wt % or less of a dimer acid, a trimer acid, or a combination thereof, 30 wt % or more and 99 wt % or less of a rosin, and 0 wt % or more and 13 wt % or less of a solvent. The dimer acid is selected from a dimer acid that is a reaction product of oleic acid and linoleic acid, a hydrogenated dimer acid obtained by adding hydrogen to a dimer acid that is a reaction product of oleic acid and linoleic acid, and a combination thereof. The trimer acid is selected from a trimer acid that is a reaction product of oleic acid and linoleic acid, a hydrogenated trimer acid obtained by adding hydrogen to a trimer acid that is a reaction product of oleic acid and linoleic acid, and a combination thereof.

A solder paste contains a flux and a metal powder, wherein the flux contains: 0.5% by mass to 20.0% by mass of a (carboxyalkyl)isocyanurate adduct; 5.0% by mass to 45.0% by mass of a rosin; and a solvent. The (carboxyalkyl)isocyanurate adduct is at least one selected from the group consisting of mono(carboxyalkyl)isocyanurate adducts, bis(carboxyalkyl)isocyanurate adducts and tris(carboxyalkyl)isocyanurate adducts.

A method of preparing a surface for diffusion bonding comprises contacting a binder material with a discontinuous surface comprising surface regions separated by gaps. The binder material is selectively deposited onto the surface regions and has a sufficient viscosity to form a self-supporting layer without flowing into the gaps. The self-supporting layer of binder material comprises a mass density in a range from about 0.001 g/in.sup.2 to about 0.050 g/in.sup.2. A braze powder is distributed over the self-supporting layer of binder material, and a predetermined amount of the braze powder is attached to the binder material. The discontinuous surface is then heated to remove the binder material and adhere the braze powder to the discontinuous surface. Thus, a prewet surface with a braze deposit thereon is formed.

A solder composition of the invention contains: a flux composition containing (A) a rosin resin, (B) an activator, (C) an imidazoline compound having a phenyl group, and (D) an antioxidant; and (E) solder powder, in which the (B) component contains (B1) an organic acid, the (B1) component contains at least one selected from the group consisting of (B11) 1-hydroxy-2-naphthoic acid, 3-hydroxy-2-naphthoic acid, and 1,4-dihydroxy-2-naphthoic acid, and the (C) component is at least one selected from the group consisting of 2-phenylimidazoline and 2-benzylimidazoline.