Abstract: A cationic electrodeposition coating composition containing no heavy metal-based anticorrosive agents such as lead compounds, and which is capable of forming a coating film with a high corrosion resistance. The composition contains 0.5 to 20% by weight of a compound having an N-substitued benzoxazine ring represented by formula (1), relative to a resin solid matter, and an unsaturated hydrocarbon group-containing sulfide-modified epoxy resin as a base resin: wherein R is a hydrocarbon group having 1 to 8 carbon atoms.

Abstract: A novel method for improving the coating film smoothness and a cationic electrodeposition coating composition containing no heavy metal-based rust prevention agents such as lead compounds and capable of forming a coating film with a high corrosion resistance are provided.

Abstract: The present invention is to provide a cationic electrodeposition coating composition which is free from a heavy metal rust inhibitor, such as a lead compound, from the standpoint of the influence upon environment and also is capable of providing a coating film having an excellent corrosion prevention property.

Abstract: A flux composition for brazing of an aluminum material which can feed a proper amount of flux to an area to be joined at the time of brazing and at the same time can improve working environment, and a method for brazing of an aluminum material. The method comprises: coating an aluminum material to be joined with a flux composition comprising 0.5 to 25 parts by weight of a polymeric compound having a number average molecular weight of 50000 to 5000000 and comprising repeating alkylene oxide units, 5 to 30 parts by weight of a fluoride flux, and water added in such an amount as will provide a total amount of the composition of 100 parts by weight; heating the coated area to remove water; heating the coated area to decompose and remove the polymeric compound; and then conducting heating for brazing.

Abstract: A pigment grinding resin composition for an electrodeposition paint comprising a cationic pigment grinding resin obtained by reacting a modified epoxy resin with sulfide in the presence of a monobasic acid and a hydroxyl group-containing dibasic acid, wherein said modified epoxy resin is obtained by reacting at least one epoxy resin having an epoxy equivalent of 150 to 2000 selected from the group consisting of bisphenol A, F and S type epoxy resins with a half-blocked diisocyanate, and wherein said sulfide is selected from the group consisting of 1-(2-hydroxyethylthio)-2-propanol, 1-(2-hydroxyethylthio)-2-butanol and 1-(2-hydroxyethylthio)-3-butoxy-1-propanol. By introducing the acid group into the epoxy resin, the dispersibility of the pigment and the compatibility with the main binder, etc., is improved.

Abstract: A pigment grinding resin of the formula: ##STR1## wherein, Ep is a residue of an epoxy resin having an epoxy equivalent of 150 to 2000 and a hydroxyl group equivalent of 300 to 4000; R.sup.1 represents a hydrophilic group selected from a 2-hydroxyethyl group and a group of the formula --CH.sub.2 CH(OH)CH.sub.2 R.sup.3 wherein, R.sup.3 is a hydroxyl group or a hydroxylalkyl group having 1 to 10 carbon atoms; R.sup.2 represents a hydrophilic group selected from 3-hydroxypropyl, 2-hydroxypropyl and 4-hydroxybutyl; R.sup.4 is a hydrogen atom or an alkyl, hydroxylalkyl or alkylamide group having 1 to 5 carbon atoms; m is a numerical value of 0.1 to 2.0; A is residue of a diisocyanate; B is a residue of an alcohol, an amine, a carboxylic acid, an oxime and a caprolactam having 1 to 20 carbon atoms; and n is a numerical value of 10.1 to 2.0. The pigment grinding resin of the present invention has excellent dispersibility.

Abstract: Polyglycidyl epoxy resins are modified to have a blocked isocyanate moiety bound to the resin backbone through an oxazolidone ring by reacting the epoxy resin with an asymmetrically blocked diisocyanate. Further reaction with a cationic active hydrogen compound gives a modified epoxy resin having a cationic group in addition to the blocked isocyanate moieties. The modified epoxy resins are incorporated into cathodic electrodeposition paint as a crosslinker or cationic binder resin or pigment dispersing agent.

Abstract: A cathodic electrodeposition paint containing a cationically modified epoxy resin and a crosslinker dispersed in an acidic aqueous medium is disclosed which contains an auxiliary resin component which is capable of improving the surface smoothness of the cured paint films and which is a reaction product produced by reacting a t-alkylphenol novolac epoxy resin with an amount of an active hydrogen compound sufficient to open all epoxy rings. When the thus produced auxiliary resin has a hydroxyl group, reaction thereof with a lactone or alkylene oxide, to graft a soft segment to the auxiliary resin improves not only the surface smoothness but also the impact strength of the paint films.

Abstract: Polyglycidyl epoxy resins are modified to have a blocked isocyanate moiety bound to the resin backbone through an oxazolidone ring by reacting the epoxy resin with an asymmetrically blocked diisocyanate. Further reaction with a cationic active hydrogen compound gives a modified epoxy resin having a cationic group in addition to the blocked isocyanate moieties. The modified epoxy resins are incorporated into cathodic electrodeposition paint as a crosslinker or cationic binder resin or pigment dispersing agent.

Abstract: Disclosed is a cationic resin which can produce a pigment paste having high dispersion stability, an electrodeposition paint with good storage stability and a coated film with preferred corrosion resistance. The cationic pigment grinding resin for electrodeposition paint obtained by reacting a) a hydrophobic epoxy resin obtained by reaction of a bisphenol A type epoxy resin with a half-blocked isocyanate; with b) sulfide; which contains a group having specific chemical formula in one molecule, in which said bisphenol A type epoxy resin has an epoxy equivalent of 180 to 1,000, said hydrophobic epoxy resin has a solubility parameter of 10.0 to 11.0 and a conversion rate to tertiary sulfonium is 70 to 90%.

Abstract: A thermosetting resinous composition contains (a) a polyfunctional oxazolidinone compound and (b) a polyamine which react with one another a polyurea polymer upon heating without emitting any emanating by-product. A novel class of polyfunctional oxazolidinone compounds and an improved method for producing the same are also disclosed.

Abstract: A thermosetting resinous composition contains (a) a polyfunctional oxazolidinone compound and (b) a polyamine which react with one another a polyurea polymer upon heating without emitting any emanating by-product. A novel class of polyfunctional oxazolidinone compounds and an improved method for producing the same are also disclosed.