Hydrocarbon-urethane-acrylate cpds. used in ink, varnish, paint, etc. - prepd. by reacting hydroxy-acrylate with di:isocyanate and then hydrocarbon, esp. alkyd resin or castor oil

摘要

Acrylic cpds. (I) of formula A-(O-CO.-NH-R-NH-CO-O-(CH2)m-O-CO-CH=CH2)n are new. A = hydrocarbon radical (II) contg. a fatty acid chain, opt. esterified; R = bivalent organic radical; m = integral 1-5 (esp. 2-3); n = integral 1-20 (esp.2-5). Prepn. of (I) comprises reacting a hydroxy acrylate (III) with a di-isocyanate (IV) and then adding a hydrocarbon radical consisting of a fatty acid chain with free alcohol functions. It may esp. be an alkyd resin (pref. based on coprah vegetable oil), or a triglyceride (pref. consisting of ricinoleic acid chains, e.g. ricin oil). R may esp. be toluene, hexamethylene, isophorone or dicyclohexylmethane. III may esp. be hydroxethyl acrylate (HEA) stabilised with hydroquinine mono methyl ether; or hydroxy propyl acrylate. IV may esp. be toluene diisocyanate (TDI), used together with dibutyl tin dilaurate (DBTDL) as catalyst; or hexamethylene diisocyanate. V may esp. be prepd. (a) by incorporating a colourant in I to form a conc. pigment paste which is then mixed with an epoxy-acrylate, a polyester acrylate, or any other type of acrylate, and a photoinitiator; or (b) by grinding these same materials together. USE/ADVANTAGE - Useful in prepn. of ink, varnish and paint compsns (V) which are esp. dried by exposure to UV (claimed). Drying in this way has absence of solvent (as avoiding losses to the atmos. or the need for a recovery process); almost instantaneous drying (so allowing printed material to be studied or read immediately); and a high degree of cross-linking (leading to good mechanical strength and chemical resistance). (I) do not suffer less wetting power which gives weak colouration; higher flow threshold; and offset performance, relative to conventional inks.