| abstract |
New UV-polymerisable compounds having the following formula (I); wherein: R is residue of a hyperbranched polyester core moiety of the following general formula (II); wherein: Rl is a core group which is a residue of a multifunctional aliphatic or aromatic polyol; R2 is a residue of an aliphatic or aromatic carboxylic acid having one COOH group and two or more OH groups, wherein n is the hydroxy functionality of the said carboxylic acid and is 2 or more, and m is the functionality of the polyol core group Rl and is at least 2; R3 is a residue of a diisocyanate compound; R4 is a hydrogen atom or methyl group; x is 1 -10, preferably 4 - 8; R5 is an alkylene group; R6 is -OR7, -NR7R8, -SR7 or R9, where R7 and R8 are the same or different and each is independently selected from: (v) an alkyl, acyl, aryl, alkene or alkyne group, (vi) a saturated or unsaturated, optionally aromatic, carbocyclic or heterocyclic group; wherein any of the above groups (i) and (ii) may be optionally substituted; and R9 is selected from any of H, an alkyl, aryl, alkene or alkyne group, a saturated or unsaturated optionally substituted carbocyclic or heterocyclic group, an alkylthio, alkoxycarbonyl, aryloxycarbonyl, carboxy, acyloxy, carbamoyl, cyano, dialkylphosphonato, diarylphosphonato; dialkylphosphinato or diarylphosphinato group; a (being the number of urethane-acrylate chains attached to the central core group R) is from 0 to 10, preferably from 1 to 10, more preferably from 4 to 10; b (being the number of xanthate moieties in the molecule) is from 0 to 10, preferably from 1 to 10, more preferably from 4 to 10; with the proviso that a + b is from 2 to 16, preferably from 10 to 14. UV-polymerisation of the new compounds, which comprise both urethane-acrylate and xanthate moieties, substantially avoids problems of residual photoinitiator or unreacted monomer in the final polymerised products. As such they are especially useful in the production of printing inks and packaging films for foodstuffs. as well as various coatings. |