Patent GB-1001774-A (GB)
Title: Polyurethane coating compositions
Inventor: FIELDING HAROLD CROSBIE
IPC: C09D175/04
Filed: 1963-06-19
Abstract: A pigmented polyurethane coating composition is prepared by initially mixing a pigment with an inorganic isocyanate which is either a compound containing at least one -NCO group directly attached to a phosphorus atom which carries at least one other organic substituent in addition to -NCO groups or a compound containing at least one -NCO group directly attached to an atom other than a phosphorus atom, and then blending the mixture thus obtained with an isocyanate-group-containing urethane prepolymer. Suitable phosphorus compounds are: phenoxy phosphoryl diisocyanate, phenoxy phosphorus diisocyanate, diphenoxy phosphoryl monoisocyanate, ethoxyphosphoryl diisocyanate, ethylphosphoryl diisocyanate, benzyl phosphoryl diisocyanate and phenyl phosphorus diisocyanate.  Other atoms to which the NCO group or groups may be attached are:  Si, S, Sn, Ge, As, Sb, B and Al. Examples of such compounds are: silicon tetraisocyanate, diethoxysilicone diisocyanate, sulphuryl diisocyanate, tin tetraisocyanate, dibutyltin diisocyanate, germanium tetraisocyanate, arsenic triisocyanate, antimony triisocyanate, phenyl antimony diisocyanate, boron triisocyanate, phenyl boron diisocyanate, and aluminium triisocyanate.  The isocyanate terminated prepolymers may be derived from polyethers, polyesters or polyester amides.  In Example (1) a prepolymer derived from 1 : 3-butyl glycol, trimethylol propane and tolylene diisocyanate was mixed by slurry grinding with a mixture of TiO2 and Si(NCO)4 in pentoxone and xylene.ALSO:Titanium dioxide is mixed with an inorganic isocyanate which is either a compound containing at least one -NCO group directly attached to a phosphorus atom which carries at least one ether organic constituent in addition to the -NCO groups or a compound containing at least one -NCO group directly attached to an atom other than a phosphorous atom.  Suitable phosphorus compounds are: PhOPO(NCO)2, PhOP(NCO)2, (PhO)2PO(NCO), ETOPO(NCO)2, EtPO)NCO)2,PhCH2PO)NCO)2, PhP(NCO)2.  Other compounds are Si(NCO)4, (EtO)2Si(NCO)2, SO2(NCO)2, Sn(NCO)4, (Bu)2Sn(NCO)2, Ge(NCO)4, As(NCO)3, Sb(NCO)3, PhSb(NCO)2, B(NCO)3, PhB(NCO)2, Al(NCO)3. The mixing may be carried out by milling in the presence of a solvent, e.g. ethyleneglycol monoethylether acetate, butylacetate, methoxyhexanone, pentoxone, methylethylketone, methylisobutyl ketone, xylene, toluene or "Aromasol."  The pigment is subsequently mixed with a polyurethane prepolymer.ALSO:A pigmented polyurethane coating composition is prepared by initially mixing a pigment with an inorganic isocyanate which is either a compound containing at least one -NCO group directly attached to a phosphorus atom which carries at least one other organic substituent in addition to -NCO groups or a compound containing at least one -NCO group directly attached to an atom other than a phosphorus atom, and then blending the mixture with an isocyanate terminated prepolymer.  The coating composition may contain solvents and flowing out agents, e.g. ethyl cellulose and cellulose acetobutyrate, and may be applied to wood, metals, concrete, asbestos, paper, plastics, rubber, glass and fabrics by brushing, spraying or dipping.  The pigment may be: TiO2, iron oxides, chromes, carbon black or phthalocyanines or azo compounds.