| 摘要 |
<p>Aq. paint comprises a water-thinnable polyacrylate resin (I) and a capped polyisocyanate (mixt.) (II). Prepn. of (I) comprises mixing components (A) and (B), directly or in stages, in an organic solvent (mixt.), in the presence of at least one polymerisation initiator. The resulting polyacrylate resin is then partly neutralised and dispersed in water. (A) comprises the following components (in wt.%): (a) 40-90 essentially carboxyl gp.-free (meth)acrylic acid ester (mixture), copolymerisable with (b), (c), (d) and (e); (b) 12-50 essentially carboxyl gp.-free ethylenic unsatd. monomer (mixt.) with at least one hydroxyl gp. per molecule, copolymerisable with (a), (c), (d) and (e); and (c) 0-25 essentially carboxyl gp.-free ethylenic unsatd. monomer (mixt.), copolymerisable with (a), (b), (d) and (e). (d) 2.5-15 ethylenic unsatd. monomer (mixt.) which has at least one carboxyl gp. per molecule, copolymerisable (a), (b), (c) and (e); and (e) 0-60 carboxyl gp.-free ethylenic unsatd. monomer (mixt.), copolymerisable with (a), (b), (c) and (d), whereby (a), (b) and (c) are all different. The total pts. per wt.of (a)-(e) is always 100 wt.% and the type and amt. of (a)-(e) is always such that (I) has a hydroxyl value of 60-180, and acid value of 20-100 and a glass transition temp.(Tg) of (-)40 - (+) 60 deg. C..</p> |
