Aq. coating compsn. for human body parts, textiles, wood, etc. - comprises aq., non-reactive, physically-drying polyurethane dispersion and PVA soln.

摘要

Coating compsn. (I) comprises 90-99 (pref. 96-98) wt.% aq., non-reactive, physically-drying polyurethane dispersion (II) and 1-10 (pref. 2-4) wt.% aq. PVA soln. (III). Specifically (II) has solids content 30-50 (pref. 34-39) wt.%, viscosity 50-500 mPa.s and pH 7.5-8.5; polyurethane (PU) is elastic and crosslinked, pref. 100% crosslinked. PU is based on (pref. aliphatic) polyether and/or polyester; is amine-extended, and is produced by reaction of 2 mols. di-isocyanate with 1 mol. polyol and 1 mol. diamine. Polyol has mol.wt. 500-3000 and contains ester and/or ether links. Pref. polyol is polycaprolactone, pref. with mol.wt. 530, 1250 or 2000. Di-isocyanate is IPDI and diamine is isophoronediamine (IPDA). (III) contains 10-30 (pref. 20) wt.% PVA. (I) also contains 0.1-1.0 (pref. 0.5) wt.% non-ionic foam suppressant, pref. based on paraffinic mineral oils with hydrophobic components and a silicone polymer. PVA is fully-hydrolysed PVA or PVA with degree of hydrolysis 98.0-99.8 mol.%, with residual acetyl content 0.1-1.9 wt.%, mol.wt. 23,000-88,000 and mean degree of polymerisation 530-2000. (I) contains colouring agent(s) and/or opalescent agents. USE/ADVANTAGE - (I) is useful for coating various substrates The compsn. is well tolerated by skin, and gives good protection against the damp and against harmful substances; it forms solvent-free films with high water vapour permeability, abrasion resistance and elasticity.