| 摘要 |
<p>The invention relates to a powder resin with a mp from 60 to 110°C, and a particle size from 10 to 250 µ, which comprises the reaction product of a reactive composition comprising:
a) an isocyanate component comprising a polyisocyanate with functionality of at least 2,
b) an alcoholic component, comprising :
b1) at least one polyol with OH functionality from 2 to 4,
b2) a monoalcohol component comprising :
b2.1) a monoalcohol, bearing an ethylenic unsaturation
b2.2) a saturated alcohol selected from the group of fatty alcohols,
b2.3) optionally, an additional saturated monoalcohol from non fatty monoalcohols
the molar ratios of OH functional groups, of the said alcoholic components b2.2) (possibly b2.3)) and b2.1) being defined so that the OH molar ratio of b2.2) / b2.1) or of b2.2) + b2.3) / b2.1) ranges from higher than 0.25 to 2, with the proviso that :
- the resulting said powder resin does bear at least one urethane unit with branched structure resulting from the reaction of an isocyanate component a) with a polyol component b), with said component a) having an average functionality higher than 2 or otherwise (if not higher than 2) the said component b1) having an average functionality higher than 2, with
- the resulting resin having no any crosslinked structure and being soluble in an organic solvent. The invention does also relate to a powder coating composition comprising the said resin and the resulting coatings and coated substrates for protective or decorative uses.</p> |
