Abstract: The invention relates to water-dispersible binders for cationic electrocoating finishes, which binders are reaction products of(A) low molecular weight epoxide resins containing aromatic groups and having an epoxide equivalent weight of below 375,(B) aliphatic and/or alicyclic polyfunctional alcohols and/or carboxylic acids having a molecular weight of below 350,(C) if appropriate up to 60% by weight, relative to the total binder, of polyfunctional alcohols, carboxylic acids and/or SH compounds having a molecular weight of 500-5,000 and(D) primary, secondary and/or tertiary amines and/or salts thereof or a sulfide/acid mixture or a phosphine/acid mixture, the reaction product of A and B containing 10-45% of aromatic groups, calculated as the phenylene group. By means of the binders, a higher layer thickness is obtained in electrocoating.

Abstract: The invention relates to a process for the preparation of polyester and alkyd resins from bifunctional and/or polyfunctional carboxylic acids and/or derivatives thereof and from bifunctional and/or polyfunctional alcohols. The reaction is carried out in stirred kettle reactors which are operated discontinuously and equipped with rectifying columns. During the entire reaction an entraining agent is introduced into the reaction mixture below surface level, with thorough distribution, by means of a delivery device in order to improve the transport of the products of the condensation reaction. In addition, the condensation reaction is carried out under an absolute pressure of 1.5 to 10 bar at least until the maximum reaction rate has been reached. The pressure is then reduced to atmospheric pressue at a gradient of -0.05 bar/hour to -5 bar/hour in a second reaction phase. The reaction is continued under normal pressure until the product exhibits the desired properties.

Abstract: The invention relates to water-dispersible binders which are intended for cationic electropaints and are based on reaction products which are formed from modified epoxy resins and primary and/or secondary amines and which can, if desired, also contain crosslinking agents, pigments, flow-control agents and other customary auxiliaries. They contain as reaction products those which have been prepared by reacting(A) low molecular weight epoxy resins which contain epoxy compound aromatic groups and have an epoxide equivalent weight of less than 375 with(B) aliphatic and/or alicyclic polyfunctional alcohols having hydroxyl groups or carboxylic acids having carboxylic groups and both having a molecular weight of less than 350 and addition of the hydroxyl groups and carboxylic groups to the epoxy groups of (A) in such a way that the reaction products of (A) and (B) contain 10-45% of aromatic groups, calculated as the phenylene group, and have terminal epoxy groups.

Abstract: A heat-hardenable binder mixture based on organic resins comprises an organic resin having primary and/or secondary and, if appropriate, also additional tertiary amino groups and a crosslinking agent based on an organic compound which contains at least 2 .beta.-hydroxyalkyl ester groups. The binder mixture can additionally contain pigments, fillers, crosslinking catalysts, corrosion inhibitors and other paint auxiliaries. The binder mixture is used in a process for preparing coatings by applying a coating agent in the form of a film to a substrate and subsequently hardening the film by stoving.

Abstract: The invention relates to binders for cathodically depositable coating compositions for the electrocoating lacquering process using cationic synthetic resins, which binders have been obtained by polymerizing (A) 5 to 95% by weight of ethylenically unsaturated polymerizable monomers in the presence of (B) 95 to 5% by weight of a cationic synthetic resin in an aqueous phase, the total amount of the components (A) and (B) being 100%.Esters of acrylic acid and/or methacrylic acid are preferable for use as component (A). The invention also relates to a process for preparing the binders and to their use for cathodically depositable electrocoating lacquers.

Abstract: The invention relates to a heat-hardenable binder mixture which comprises(A) an organic nonacidic resin having a hydroxyl group content of at least 0.2 equivalent in 100 g of resin and having a molecular weight of at least 850, and(B) a crosslinking agent based on an organic compound which contains at least 2 carbalkoxymethyl ester groups per molecule.

Abstract: The invention relates to binders for cathodically depositable coating compositions for the electrocoating lacquering process using cationic synthetic resins, which binders have been obtained by polymerizing (A) 5 to 95% by weight of ethylenically unsaturated polymerizable monomers in the presence of (B) 95 to 5% by weight of a cationic synthetic resin in an aqueous phase, the total amount of the components (A) and (B) being 100%. Esters of acrylic acid and/or methacrylic acid are preferable for use as component (A). The invention also relates to a process for preparing the binders and to their use for cathodically depositable electrocoating lacquers.

Abstract: The invention relates to water-dispersible binders for cationic electrocoating finishes, which are obtained by reaction of(A) epoxy resins containing low molecular weight aromatic groups and having an epoxide equivalent weight of less than 375 with(B) aliphatic and/or alicyclic polyfunctional alcohols or carboxylic acids having a number average molecular weight of less than 350, further reaction of the product of (A) and (B) with(C) a polyfunctional alcohol having a molecular weight of more than 350, addition at the epoxide groups taking place so that the reaction products of (A) and (B) contain an amount of aromatic groups of from 10 to 45% by weight, calculated as phenylene groups, and further modification of the resulting intermediate with(D) primary and/or secondary amines or ammonium salts in order to achieve the required water-dispersibility.

Abstract: The invention relates to a self-crosslinking heat-curable binder, in particular for electropaints, which is based on an organic synthetic resin which contains primary and/or secondary and, if desired, also tertiary amino groups and esterified carboxyl groups and is water-dilutable due to partial or complete neutralization with acids. The esterified carboxyl groups are activated in the alcohol component by a substituent which induces a negative inductive effect.

Abstract: A process for coating an electrically conductive substrate, connected as the cathode, with a cationic coating agent from an electrocoating bath and subsequently hardening the coating, is characterized in that an aqueous dispersion made from:A. cationic, synthetic resins which have been protonated with acids, contain basic groups and are in a dissolved or dispersed form andB. dispersed, finely divided, ionic plasticsis used as the cationic coating agent.

Abstract: The invention relates to a self-crosslinking heatcurable binder, in particular for electropaints, which is based on an organic synthetic resin which contains primary and/or secondary and, if desired, also tertiary amino groups and esterified carboxyl groups and is water-dilutable due to partial or complete neutralization with acids. The esterified carboxyl groups are activated in the alcohol component by a substituent which induces a negative inductive effect.

Abstract: The invention relates to a selfcrosslinking heat-hardenable binder, in particular for electropaints, which is based on an organic synthetic resin which contains hydroxyl groups and esterified carboxyl groups in the form of carbalkoxymethyl ester groups and is water-dilutable by partial or complete acid-neutralization of amino groups present in the resin.

Abstract: A heat-hardenable binder mixture based on organic resins comprises an organic resin having primary and/or secondary and, if appropriate, also additional tertiary amino groups and a crosslinking agent based on an organic compound which contains at least 2 .beta.-hydroxyalkyl ester groups. The binder mixture can additionally contain pigments, fillers, crosslinking catalysts, corrosion inhibitors and other paint auxiliaries. The binder mixture is used in a process for preparing coatings by applying a coating agent in the form of a film to a substrate and subsequently hardening the film by stoving.

Abstract: The invention relates to water-dispersible binders which are intended for cationic electropaints and are based on reaction products which are formed from modified epoxy resins and primary and/or secondary amines and which can, if desired, also contain crosslinking agents, pigments, flow-control agents and other customary auxiliaries.

Abstract: A process for coating an electrically conductive substrate, connected as the cathode, with a cationic coating agent from an electrocoating bath and subsequently hardening the coating, is characterized in that an aqueous dispersion made fromA. cationic, synthetic resins which have been protonated with acids, contain basic groups and are in a dissolved or dispersed form andB. dispersed, finely divided, ionic plasticsis used as the cationic coating agent.

Abstract: Baking finishes which do not pollute the environment and which comprise a mixture of a polymer having hydroxyl groups, a furoxane of the formula ##STR1## WHERE R is a 2n-valent hydrocarbon radical of 2 to 20 carbon atoms and n is an integer from 1 to 4, and, if appropriate, suitable assistants.

Abstract: A pulverulent coating agent which consists of a mixture of:A. a compound having at least two aziridine ring groupings per molecule;B a binder which contains hydroxyl groups and which is solid at ambient temperature; and optionallyC one or more other additives.The coating agent is particularly suitable for powder coating metal surfaces.