Abstract:
The present invention relates to water dilutable, urethane group-containing polyester polyols having an acid number of 6 to 45 mg KOH/g, wherein 25 to 100% of the acid groups are neutralized by bases, a hydroxyl number of 20 to 250 mg KOH/g, a molecular weight (M.sub.w) of 2,000 to 150,000 and a urethane content (--NH--CO--O--) of 2 to 16% by weight, wherein the polyester polyol is the at least partly neutralized reaction product ofa) 35 to 90% by weight of branched polyester polyols having a hydroxyl number of 40 to 600 and prepared froma1) 0 to 60% by weight of monocarboxylic acids,a2) 6 to 65% by weight of di- and/or tricarboxylic acids or their anhydrides,a3) 10 to 70% by weight of alcohols,a4) 0 to 35% by weight of monoalcohols,a5) 0 to 30% by weight of hydroxycarboxylic acids, aminocarboxylic acids, lactones, lactams and aminoalcohols anda6) 0 to 45% by weight of polycarbonate polyols,b) 0.5 to 8.5% by weight of hydroxycarboxylic acidsc) 0 to 15% by weight of compounds containing OH, NH and/or NH.sub.2 groups and having a molecular weight of 32 to 500,d) 3 to 33% by weight of compounds containing isocyanate groups and having a molecular weight of 168 to 2,000 ande) 0 to 45% by weight of polycarbonate polyols,wherein the percentages of a) to e) and a1) to a6) add up to 100% and wherein the urethane group-containing polyester polyols contain 1 to 25% by weight of carbonate groups (--0--CO--O--) incorporated through components e) and/or a6).
Abstract:
The present invention relates to polyisocyanates which contain ester groups and havea) a content of aliphatically bound isocyanate groups of 18 to 33% by weight,b) an average NCO functionality of 4.1 to 10, preferably from 4.5 to 10, andc) a viscosity of 200 to 2,5000 mPa.s at 22.degree. C.The present invention also relates to preferred polyisocyanates which contain ester groups and havea) a content of aliphatically bound isocyanate groups of 20 to 33% by weight,b) an average NCO functionality of 5 to 8 andc) a viscosity of 500 to 1,000 mPa.s at 22.degree. C.The present invention further relates to a process for the preparation of these preferred polyisocyanates by reacting isocyanatocarboxylic acid chlorides with O-silylated, polyhydric alcohols at a temperature of about 50.degree. to 150.degree. C. Finally, the present invention relates to the use of the polyisocyanates as the isocyanate component for two-component polyurethane coating compositions.
Abstract:
The present invention is directed to polyisocyanates containing a stabilizing amount of a carboxylic acid corresponding to the formula ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 represent hydrogen or C.sub.1 -C.sub.5 -alkyl andX and Y represent hydrogen, chlorine or methyl, with the proviso that when X=Cl, Y=H or CH.sub.3 and when Y=Cl, X=H or CH.sub.3.The present invention is also directed to the use of the stabilized polyisocyanates as binders for coating compositions, sealing compounds and adhesives.
Abstract:
The present invention relates to new binder combinations comprising(A) 99-30 parts by weight of OH-functional graft copolymer resins prepared by copolymerization of a polybutadiene having a molecular weight of from 500 to 10000 and containing more than 30% of 1,2-vinyl structure with selected olefinically unsaturated monomers and(B) 1 to 70 parts by weight of a multifunctional crosslinking resin, preferably a polyisocyanate resin. The new binder combinations are suitable for preparing coatings having a very high level of elasticity and an excellent surface hardness.
Abstract:
The present invention relates to a process for the production of aqueous dispersions which form powder coatings at room temperature, have an average particle size of 0.1 to 10 .mu.m, contain polyols and blocked polyisocyanate crosslinking agents, and, after stoving, yield coatings with improved water and solvent resistance, in particular on metallic substrates.
Abstract:
The present invention relates to polyisocyanate-modified dicarboxylic acid derivatives obtainable by reacting organic polyisocyanates with excess quantities, based on the equivalent ratio of NCO/COOH groups, of dicarboxylic acid (poly)anhydrides containing free carboxyl groups and water. The present invention also relates to coating compositions, in particular powder coating compositions, containing these polyisocyanate-modified dicarboxylic acids as curing agents for resins containing epoxy groups.
Abstract:
Polyisocyanate-modified dicarboxylic (poly)anhydrides which are solid below 40.degree. C., liquid above 120.degree. C. and based on the reaction product of organic polyisocyanates with more than equivalent quantities, based on the NCO/COOH reaction, of dicarboxylic (poly)anhydrides containing free carboxyl groups and optional subsequent modification of the reaction product with less than equivalent quantities, based on the anhydride groups, of anhydride-reactive amino and/or hydroxyl groups; and powder coating compositions containing as binder these polyisocyanate-modified dicarboxylic (poly)anhydrides as curing agents for polyepoxides.
Abstract:
The present invention relates to an aqueous coating composition containing a) a urethane (meth)acrylate having (meth)acryloyl groups and optionally free isocyanate groups, b) optionally a further polyisocyanate, c) a UV initiator which initiates polymerization by a free radical mechanism, and d) one or more aqueous binders containing isocyanate-reactive groups. The present invention also relates to the use of the coating compositions for coating various substrates, especially metal substrates.
Abstract:
The present invention relates to aqueous polyurethane-urea dispersions having a resin solids content of at least 35 wt. % and a pH of at least 7.5 which are prepared bya) forming an isocyanate-terminated prepolymer by reacting a difunctional polyol having a molecular weight of 500 to 6000, a low molecular weight alcohol, a diisocyanate and/or triisocyanate and an isocyanate-reactive compound which has an acid group,b) neutralizing 65% to 95% of the acid groups prior to dispersing the prepolymer in water,c) dispersing the neutralized prepolymer in water,d) chain extending the isocyanate groups with water to form a polyurethane-urea, ande) after completion of the chain extending reaction adding additional neutralizing agent to provide a total amount of neutralizing agent that is sufficient to neutralize at least 115% of the acid groups of component D),wherein the polyurethane-urea contains 1.0 to 4.0%, based on resin solids, of the isolated urea groups. The present invention also relates to a process for the preparation of these polyurethane-urea dispersions and to their use in coating compositions.
Abstract:
An aqueous binder composition having a reduced tendency to yellow containingA) 20 to 95 wt-% of a water-dilutable organic polyol component that is present in the form of an aqueous solution or dispersion, contains one or more polymer-modified polyester resins which contain carboxylate groups and hydroxyl groups and has been prepared by the polymerization of olefinically unsaturated monomers in the presence of an unsaturated polyester resin that is copolymerized with the monomers andB) 5 to 80 wt-% of at least one heat-activatable cross-linking resin,wherein the percentages are based on the solids contents of components A) and B) and add up to 100%; and their use in heat-curable coating compositions.