Moisture curing polyurethane topcoat paint displaying geometric metamerism

A high-solids, moisture curable topcoat paint composition containing a metal flake pigment and formulated to be applied by spray onto a substrate and to flow and cure thereon into a polyurethane film in which the metal flakes lie at varying depths and are oriented substantially parallel to the film surface, whereby said film displays a high degree of geometric metamerism, said composition comprising

• as the binder resin forming component an isocyanate-terminated, moisture curable prepolymer which is the catalyzed reaction product of a mixture comprising an aliphatic diisocyanate, a polyoxypropylene diol and a polyoxypropylene polyol having a hydroxyl functionality of at least three, the ratio of isocyanate groups to total hydroxyl groups initially being at least 2 to 1,
• a color producing pigment,
• metal flakes,
• a catalyst to enhance the moisture curing of said paint composition, and
• a solvent formulated to produce the viscosity in the freshly applied film of 10 or less poises measured at a shear rate of 15.7 sec.sup.-1,
• the combination of said constituents in a curing film produced from said composition cooperating to orient the metal flakes as desired.

A high-solids, moisture curable topcoat paint composition containing a metal flake pigment and formulated to be applied by spray onto a substrate and to flow and cure thereon into a polyurethane film in which the metal flakes lie at varying depths and are oriented substantially parallel to the film surface, whereby said film displays a high degree of geometric metamerism, said composition comprising

• as the binder resin forming component an isocyanate-terminated, moisture curable prepolymer which is the catalyzed reaction product of a mixture comprising an aliphatic diisocyanate, a polyoxypropylene diol and a polyoxypropylene polyol having a hydroxyl functionality of at least three, the ratio of isocyanate groups to total hydroxyl groups initially being at least 2 to 1,
• a color producing pigment,
• metal flakes,
• a catalyst to enhance the moisture curing of said paint composition, and
• a solvent formulated to produce the viscosity in the freshly applied film of between 1 and 5 poises measured at a shear rate of 15.7 sec.sup.-1,
• the combination of said constituents in a curing film produced from said composition cooperating to orient the metal flakes as desired.

A high-solids, moisture curable topcoat paint composition containing a metal flake pigment and formulated to be sprayed onto a substrate and to flow and cure thereon in a polyurethane film in which the metal flakes are oriented so as to interact with incident light to produce geometric metamerism, said composition comprising

• as the binder resin forming component an isocyanate-terminated, moisture curable prepolymer which is the reaction product of methylene bis (4-cyclohexyl isocyanate) and an isocyanate group-reactive mixture comprising a polyoxypropylene diol and a polyoxypropylene polyol having a hydroxyl functionality of at least three, the ratio of isocyanate groups to total hydroxyl groups initially being at least 2 to 1,
• a color producing pigment,
• metal flakes,
• a catalyst to enhance the moisture curing of said paint composition, and
• a solvent, if required, in an amount to reduce the viscosity of the composition for spray application, the nonvolatile content of the composition making up at least 60% of the total,
• the combination of said constituents in a curing film produced from said composition cooperating to permit the metal flakes to orient substantially parallel to the surface of the cured film.

A high-solids, moisture curable topcoat paint composition containing an aluminum flake pigment and formulated to be sprayed onto a substrate and to flow and cure thereon into a polyurethane film in which the metal flakes are oriented so as to interact with incident light to produce geometric metamerism, said composition comprising

• as the binder resin forming component an isocyanate-terminated, moisture curable prepolymer which is the catalyzed reaction product of a mixture consisting essentially of methylene bis (4-cyclohexyl isocyanate), a polyoxypropylene diol, a polyoxypropylene polyol having a hydroxyl functionality of at least three and bis (2,2,6,6 tetramethyl piperidinyl-4) sebacate, the ratio of isocyanate groups to total hydroxyl groups and amine groups initially being at least 1.5 to 1, said bis piperidinyl sebacate being chemically reacted into the prepolymer molecules,
• a color producing pigment,
• aluminum flakes,
• a catalyst to enhance the moisture curing of said paint composition, and
• a solvent in an amount to reduce the viscosity of the composition for spray application, the nonvolatile content of the composition making up 60 to 70 weight percent of the total,
• the combination of said constituents in a curing film produced from said composition cooperating to permit the aluminum flakes to orient substantially parallel to the surface of the cured film, the cured film thereby displaying a high degree of geometric metamerism and further having improved stability when exposed to ultraviolet radiation.

A high-solids, moisture curable topcoat paint composition containing a metal flake pigment and formulated to be sprayed onto a substrate and to flow and cure thereon into a polyurethane film in which the metal flakes are oriented so as to interact with incident light to produce geometric metamerism, said composition comprising

• as the binder resin forming component an isocyanate-terminated, moisture curable prepolymer which is the catalyzed reaction product of a mixture consisting essentially of methylene bis (4-cyclohexyl isocyanate), a polyoxypropylene diol, a polyoxypropylene polyol having a hydroxyl functionality of at least three and bis (2,2,6,6 tetramethyl piperidinyl-4) sebacate, the ratio of the isocyanate groups to total hydroxyl groups initially being at least 2 to 1, said bis piperidinyl sebacate being chemically reacted into the prepolymer molecules,
• a color producing pigment,
• aluminum flakes,
• a catalyst to enhance the moisture curing of said paint composition, and
• a solvent in an amount to reduce the viscosity of the composition for spray application, the nonvolatile content of the composition making up 60 to 70 weight percent of the total,
• the combination of said constituents in a curing film produced from said composition cooperating to permit the aluminum flakes to orient substantially parallel to the surface of the cured film, the cured film thereby displaying a high degree of geometric metamerism and further having improved stability when exposed to ultraviolet radiation.