A blocking agent dissociation catalyst for blocked isocyanates comprising a nitrogen-containing compound represented by Formula (1a):

##STR00001##

wherein D is represented by Formula (2):

##STR00002##

wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, and a are as described in the specification.

The present invention relates to a multi-aziridine compound having: a) at least 2 of the following structural units (A): (A) whereby R.sub.1 is H; R.sub.2 and R.sub.4 are independently chosen from H, a linear group containing from 1 to 8 carbon atoms and optionally containing one or more heteroatoms, a branched or cyclic group containing from 3 to 8 carbon atoms and optionally containing one or more heteroatoms, phenyl, benzyl, or pyridinyl; R.sub.3 is chosen from a linear group containing from 1 to 8 carbon atoms and optionally containing one or more heteroatoms, a branched or cyclic group containing from 3 to 8 carbon atoms and optionally containing one or more heteroatoms, phenyl, benzyl, or pyridinyl; or R.sub.2 and R.sub.3 (in case R.sub.2 is different than H) may be part of the same cyclic group containing from 3 to 8 carbon atoms; R′ and R″ are independently H or an aliphatic hydrocarbon group containing from 1 to 12 carbon atoms; and b) a molecular weight from 600 to 20000 Daltons, wherein the molecular weight is determined using MALDI-TOF mass spectrometry according to the description.

##STR00001##

The present invention relates to a multi-aziridine compound having: a) at least 2 of the following structural units (A): (A) whereby R.sub.1 is H; R.sub.2 and R.sub.4 are independently chosen from H, a linear group containing from 1 to 8 carbon atoms and optionally containing one or more heteroatoms, a branched or cyclic group containing from 3 to 8 carbon atoms and optionally containing one or more heteroatoms, phenyl, benzyl, or pyridinyl; R.sub.3 is chosen from a linear group containing from 1 to 8 carbon atoms and optionally containing one or more heteroatoms, a branched or cyclic group containing from 3 to 8 carbon atoms and optionally containing one or more heteroatoms, phenyl, benzyl, or pyridinyl; or R.sub.2 and R.sub.3 (in case R.sub.2 is different than H) may be part of the same cyclic group containing from 3 to 8 carbon atoms; R′ and R″ are independently H or an aliphatic hydrocarbon group containing from 1 to 12 carbon atoms; and b) a molecular weight from 600 to 20000 Daltons, wherein the molecular weight is determined using MALDI-TOF mass spectrometry according to the description.

##STR00001##

The present invention relates to a multi-aziridine compound having: a) from 2 to 6 of the following structural units (A): whereby R′, R″ are as defined herein m is an integer from 1 to 6; b) one or more linking chains wherein each one of these linking chains links two of the structural units A; and c) a molecular weight in the range from 840 Daltons to 5000 Daltons. The multi-aziridine compound can be used for example for crosslinking of for example carboxylic acid functional polymers dissolved and/or dispersed in an aqueous medium.

##STR00001##

The present invention relates to a multi-aziridine compound having: a) from 2 to 6 of the following structural units (A): whereby R′, R″ are as defined herein m is an integer from 1 to 6; b) one or more linking chains wherein each one of these linking chains links two of the structural units A; and c) a molecular weight in the range from 840 Daltons to 5000 Daltons. The multi-aziridine compound can be used for example for crosslinking of for example carboxylic acid functional polymers dissolved and/or dispersed in an aqueous medium.

##STR00001##

The present invention relates to an aqueous coating composition comprising a multi-aziridine compound and a carboxylic acid functional polymer, characterized in that (i) the composition is an aqueous dispersion having a pH ranging from 8 to 14, (ii) the aqueous dispersion comprises particles X which particles X comprise multi aziridine compound and particles Y which particles Y comprise carboxylic acid functional polymer, and (iii) said multi-aziridine compound has: a) from 2 to 6 of the following structural units A: b) one or more linking chains wherein each one of these linking chains links two of the structural units A; and c) a molecular weight in the range from 500 to 10000 Daltons.

##STR00001##

The present invention relates to an aqueous coating composition comprising a multi-aziridine compound and a carboxylic acid functional polymer, characterized in that (i) the composition is an aqueous dispersion having a pH ranging from 8 to 14, (ii) the aqueous dispersion comprises particles X which particles X comprise multi aziridine compound and particles Y which particles Y comprise carboxylic acid functional polymer, and (iii) said multi-aziridine compound has: a) from 2 to 6 of the following structural units A: b) one or more linking chains wherein each one of these linking chains links two of the structural units A; and c) a molecular weight in the range from 500 to 10000 Daltons.

##STR00001##

The present invention relates to a multi-aziridine compound having: ⋅a) from 2 to 6 of the following structural units (A): whereby R.sub.1 is H, R.sub.2 and R.sub.4 are independently chosen from H or an aliphatic hydrocarbon group containing from 1-4 carbon atoms, R.sub.3 is an aliphatic hydrocarbon group containing from 1-4 carbon atoms, R′═H or an aliphatic hydrocarbon group containing from 1 to 4 carbon atoms; R″ and R′″ are independently chosen from an aliphatic hydrocarbon group containing from 1 to 4 carbon atoms, a cycloaliphatic hydrocarbon group containing from 4 to 12 carbon atoms or an aromatic hydrocarbon group containing from 6 to 12 carbon atoms, b) one or more linking chains wherein each one of these linking chains links two of the structural units A; and c) a molecular weight in the range from 600 Daltons to 5000 Daltons.

##STR00001##

The present invention relates to a multi-aziridine compound having: ⋅a) from 2 to 6 of the following structural units (A): whereby R.sub.1 is H, R.sub.2 and R.sub.4 are independently chosen from H or an aliphatic hydrocarbon group containing from 1-4 carbon atoms, R.sub.3 is an aliphatic hydrocarbon group containing from 1-4 carbon atoms, R′═H or an aliphatic hydrocarbon group containing from 1 to 4 carbon atoms; R″ and R′″ are independently chosen from an aliphatic hydrocarbon group containing from 1 to 4 carbon atoms, a cycloaliphatic hydrocarbon group containing from 4 to 12 carbon atoms or an aromatic hydrocarbon group containing from 6 to 12 carbon atoms, b) one or more linking chains wherein each one of these linking chains links two of the structural units A; and c) a molecular weight in the range from 600 Daltons to 5000 Daltons.

##STR00001##

The present invention relates to a multi-aziridine crosslinker composition, characterized in that the composition is an aqueous dispersion having a pH ranging from 9 to 14 and comprising a multi-aziridine compound in dispersed form, wherein said multi-aziridine compound has: a. from 2 to 6 of the following structural units A: (A) whereby R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are H; m is 1, R′ and R″ are according to (1) or (2): (2) R′═H or an aliphatic hydrocarbon group containing from 1 to 14 carbon atoms, and R″=an alkyl group containing from 1 to 4 carbon atoms, CH2-O—(C═O)—R′″ or CH2-O—R″″, whereby R′″ is an alkyl group containing from 4 to 12 carbon atoms and R″″ is an alkyl group containing from 1 to 14 carbon atoms, (2) R′ and R″ form together a saturated cycloaliphatic hydrocarbon group containing from 5 to 8 carbon atoms; b. one or more linking chains wherein each one of these linking chains links two of the structural units A; and c. a molecular weight in the range from 600 to 10000 Daltons.

##STR00001##