Water-dispersible binders for cationic electro-dip paints, and method for their production

Claim 1

A water-dispersible binder for cationic electro-dip paints, obtained by reaction of (A) a low molecular weight epoxy resin, containing aromatic groups and having an epoxy equivalent weight under 375, with (B) an aliphatic and/or alicyclic poly-functional alcohol and/or a carboxylic acid having a mean molecular weight under 350 to an epoxy group-containing intermediate product which contains a proportion of aromatic groups, calculated as phenylene group, of 10 to 45 percent by weight, and further modification of the resulting intermediate product with (C) a compound having a molecular weight over 350 and being of the formula ##STR8## wherein X is alkylene, arylene, alkarylene, O, O-alkylene, O-arylene, O-alkarylene, S, S-alkylene, S-arylene, S-alkarylene, --CO, CO-alkylene, CO-arylene, CO-alkarylene, --SO 2 --, SO 2 -alkylene, SO 2 -arylene or SO 2 -alkarylene; x is 0 or 1; Y is X, ##STR9## Z is alkylene, polyester, polyether, polycarbonate or polyurethane; R is H, CH 3 , alkyl, --OH--CH 3 , --O-alkyl, --NO 2 , --NR'R" or --NHCOR'"; provided that when X is O, NH or S, Y is other than O, O-alkylene, O-arylene, O-alkarylene, S, S-alkylene, S-arylene, S-alkarylene, --NHCO--, NH-alkylene, NH-arylene or NH-alkarylene; when X is CO or SO 2 , Y is other than CO, CO-alkylene, CO-arylene, CO-alkarylene, SO 2 , SO 2 -alkylene, SO 2 -arylene, SO 2 -alkarylene or CO 2 --; to provide a second intermediate product and further reaction of the second intermediate product with (D) a primary and/or secondary amine or ammonium salt to achieve the required dispersibility in water.

Claim 10

A method for the production of a binder for cationic electro-dip paints with a base of a reaction product of a modified epoxy resin and a primary, secondary and/or tertiary amine as well as an ammonium salt or sulfide/acid or phosphine/acid mixture which contains a crosslinking agent, a pigment, and a leveling agent comprising: (A) reacting a low molecular weight epoxy resin containing aromatic groups and having an epoxide equivalent weight epoxy resin containing armomatic groups and having an epoxide equivalent weight under 375 with (B) an aliphatic and/or alicyclic poly-functional alcohol or carboxylic acid having a molecular weight under 350 to cause addition to the epoxide groups and to produce an intermediate product containing epoxide groups, the relative ratios of (A) and (B) being calculated so that the intermediate product contains a proportion of aromatic groups, calculated as phenylene group, of 10 to 45%; and further reacting the intermediate product with (C) an elasticized polyphenol having a molecular weight over 350 and being of the formula ##STR10## wherein X is alkylene, arylene, alkarylene, O, O-alkylene, O-arylene, O-alkarylene, S, S-alkylene, S-arylene, S-alkarylene, --CO--, CO-alkylene, CO-arylene, CO-alkarylene, --SO 2 --, SO 2 -alkylene, SO 2 -arylene, SO 2 -alkarylene, NH, NH-alkylene, NH-arylene, NH-alkarylene; x is 0 or 1; Y is X, ##STR11## Z is alkylene, polyester, polyether, polyamide, polycarbonate, polyurethane; R is H, CH 3 , alkyl-, --O--CH 3 , --O-alkyl, --NO 2 , --NR' 2 , --NR'R", --NHCOR'". provided that when X is O or S, Y is other than O, O-alkylene, O-arylene, O-alkarylene, S, S-alkylene, S-arylene, S-alkarylene, --NHCO--, NH-alkylene, NH-arylene or NH-alkarylene; when X is CO or SO 2 , Y is other than CO, CO-alkylene, CO-arylene, CO-alkarylene, SO 2 , SO 2 -alkylene, SO 2 -arylene, SO 2 -alkarylene or --CO 2 --; to produce a second intermediate product; and, to obtain the required dispersibility in water, reacting the second intermediate product with (D) a primary and/or secondary amine and/or the salt thereof.

Claim 11

A method for the production of a binder for cationic electro-dip paints with a base of a reaction product of a modified epoxy resin and a primary, secondary and/or tertiary amine as well as an ammonium salt or sulfide/acid or phosphine/acid mixture which contains a crosslinking agent, a pigment, and a leveling agent comprising: (A) reacting a low molecular weight epoxy resin containing aromatic groups and having an epoxide equivalent weight epoxy resin containing armomatic groups and having an epoxide equivalent weight under 375 with (B) an aliphatic and/or alicyclic poly-functional alcohol or carboxylic acid having a molecular weight under 350 to cause addition to the epoxide groups and to produce an intermediate product containing epoxide groups, the relative ratios of (A) and (B) being calculated so that the intermediate product contains a proportion of aromatic groups, calculated as phenylene group, of 10 to 45%; and further reacting the intermediate product with (C) an elasticized polyphenol having a molecular weight over 350 and being of the formula ##STR10## wherein X is alkylene, arylene, alkarylene, O, O-alkylene, O-arylene, O-alkarylene, S, S-alkylene, S-arylene, S-alkarylene, --CO--, CO-alkylene, CO-arylene, CO-alkarylene, --SO 2 --, SO 2 -alkylene, SO 2 -arylene, SO 2 -alkarylene, NH, NH-alkylene, NH-arylene, NH-alkarylene; x is 0 or 1; Y is X, ##STR11## Z is alkylene, polyester, polyether, polyamide, polycarbonate, polyurethane; R is H, CH 3 , alkyl-, --O--CH 3 , --O-alkyl, --NO 2 , --NR' 2 , --NR'R", --NHCOR'". provided that when X is O or S, Y is other than O, O-alkylene, O-arylene, O-alkarylene, S, S-alkylene, S-arylene, S-alkarylene, --NHCO--, NH-alkylene, NH-arylene or NH-alkarylene; when X is CO or SO 2 , Y is other than CO, CO-alkylene, CO-arylene, CO-alkarylene, SO 2 , SO 2 -alkylene, SO 2 -arylene, SO 2 -alkarylene or --CO 2 --; to produce a second intermediate product; and, to obtain the required dispersibility in water, reacting the second intermediate product with (D) a primary and/or secondary amine and/or the salt thereof.

Claim 19

A method for the electrophoretic coating of an electrically conductive substrate, connected as cathode, from an aqueous bath with a base of a cationic binder at least partially neutralized with acid the binder having been made spontaneously cross-linkable by reaction, or the bath containing an additional crosslinking agent, the binder is a reaction product of (A) a low molecular weight epoxy resin containing aromatic groups and having an epoxide equivalent weight under 375. (B) an aliphatic and/or alicyclic poly-functional alcohol and/or carboxylic acid having a molecular weight under 350; (C) an elasticized polyphenol having a molecular weight over 350; and (D) a primary and/or secondary amine and/or an ammonium salt the reaction product of A and B having a content of aromatic groups, calculated as phenylene group, of 10-45%; the polyphenol having the formula ##STR12## wherein X is alkylene, arylene, alkarylene, O, O-alkylene, O-arylene, O-alkarylene, S, S-alkylene, S-arylene, S-alkarylene, --CO--, CO-alkylene, CO-arylene, CO-alkarylene, --SO 2 --, SO 2 -alkylene, SO 2 -arylene, SO 2 -alkarylene, NH, NH-alkylene, NH-arylene, NH-alkarylene; X is 0 or 1; Y is X, ##STR13## Z is alkylene, polyester, polyether, polyamide, polycarbonate, polyurethane; R is H, CH 3 , alkyl, --O--CH 3 , --O-alkyl, NO 2 , --NR' 2 , --NR'R", --NHCOR'"; provided that when X is O or S, Y is other than O, O-alkylene, O-arylene, O-alkarylene, S, S-alkylene, S-arylene, S-alkarylene, --NHCO--, NH-alkylene, NH-arylene or NH-alkarylene when X is CO or SO 2 , Y is other than CO, CO-alkylene, CO-arylene, CO-alkarylene, SO 2 , SO 2 -alkylene, SO 2 -arylene, SO 2 -alkarylene, or --CO 2 --.

Claim 20

A method for the electrophoretic coating of an electrically conductive substrate, connected as cathode, from an aqueous bath with a base of a cationic binder at least partially neutralized with acid the binder having been made spontaneously cross-linkable by reaction, or the bath containing an additional crosslinking agent, the binder is a reaction product of (A) a low molecular weight epoxy resin containing aromatic groups and having an epoxide equivalent weight under 375. (B) an aliphatic and/or alicyclic poly-functional alcohol and/or carboxylic acid having a molecular weight under 350; (C) an elasticized polyphenol having a molecular weight over 350; and (D) a primary and/or secondary amine and/or an ammonium salt the reaction product of A and B having a content of aromatic groups, calculated as phenylene group, of 10-45%; the polyphenol having the formula ##STR12## wherein X is alkylene, arylene, alkarylene, O, O-alkylene, O-arylene, O-alkarylene, S, S-alkylene, S-arylene, S-alkarylene, --CO--, CO-alkylene, CO-arylene, CO-alkarylene, --SO 2 --, SO 2 -alkylene, SO 2 -arylene, SO 2 -alkarylene, NH, NH-alkylene, NH-arylene, NH-alkarylene; X is 0 or 1; Y is X, ##STR13## Z is alkylene, polyester, polyether, polyamide, polycarbonate, polyurethane; R is H, CH 3 , alkyl, --O--CH 3 , --O-alkyl, NO 2 , --NR' 2 , --NR'R", --NHCOR'"; provided that when X is O or S, Y is other than O, O-alkylene, O-arylene, O-alkarylene, S, S-alkylene, S-arylene, S-alkarylene, --NHCO--, NH-alkylene, NH-arylene or NH-alkarylene when X is CO or SO 2 , Y is other than CO, CO-alkylene, CO-arylene, CO-alkarylene, SO 2 , SO 2 -alkylene, SO 2 -arylene, SO 2 -alkarylene, or --CO 2 --.