Self-emulsifiable polyisocyanate mixture and aqueous coating or adhesive composition comprising the mixture

A self-emulsifiable polyisocyanate mixture having (i) a free hexamethylene diisocyanate monomer content of not more than 1.0% by weight and (ii) an average NCO functionality of 2.0 to 3.7

• obtained by subjecting hexamethylene diisocyanate to urethanation with
• (a) a carbon-branched dihydric alcohol having overall 4 to 35 carbon atoms, of which 2 to 33 carbon atoms are a total number of the carbon atoms possessed by one or more branches, wherein component (a) is bonded in a proportion of 0.1 to 15% by weight based on the weight of the self-emulsifiable polyisocyanate compound,
• (b) a hydrophilic surfactant having one or more active hydrogen atoms capable of reacting with isocyanate group and 3 to 90 alkylene oxide units, wherein component (b) is bonded in a proportion of 0.1 to 40% by weight based on the weight of the self-emulsifiable polyisocyanate mixture,
• (c) optionally an aliphatic compound having one or more active hydrogen atoms capable of reacting with isocyanate group and 8 or more carbon atoms, wherein component (6) is bonded in a proportion of 0 to 30% by weight based on the weight of the self-emulsifiable polyisocyanate compound, and
• (d) optionally a carbon-unbranched glycol having 1 to 10 carbon atoms, wherein component (d) is bonded in a proportion of 0 to 5% by weight based on the weight of the self-emulsifiable polyisocyanate mixture, and
• to uretdione-forming reaction and isocyanurate-forming reaction, and wherein
• (1) the percentage of hexamethylene diisocyanate dimer having uretdione group corresponds to an area percentage determined by a differential refractometer detection in a gel permeation chromatography (GPC) of 3 to 55%, and
• (2) the percentage of hexamethylene diisocyanate trimer having isocyanurate group corresponds to an area percentage determined by a differential refractometer detection in the GPC of 5 to 45%.