[Problem] In a coating method of a two-coat one-bake system where a clear coat paint is coated after a base coat paint is coated, then these two coated layers are simultaneously hardened, adhesive strength between the two coated layers is to increase in comparison with the conventional method. [Solution] Provided is a coating method; A specific hardener is used in the clear coat paint. The hardener is one containing a polyisocyanate derived from 1,6-hexamethylene diisocyanate, satisfying all the following conditions: 1) Hardener does not virtually include diisocyanate monomer, 2) Viscosity of hardener is not more than 1000 mPa.Math.s/23 C., 3) Content of HDI trimer in hardener is not less than 60 weight %, and 4) Content of HDI dimer in hardener is less than 10 weight %.

The present invention relates to a method for coating plastics substrates with an aqueous coating composition (A) comprising at least one organic polymer as binder, said coating composition being applied to at least one surface (O) of the plastics substrate and being subsequently cured, wherein (i) the application of the coating composition (A) is preceded by the application of a carbene-forming compound (C) of the formula (I) below

##STR00001##

where
R.sub.1=(CX.sub.2).sub.nX, where X=F or Cl, and n=0 or 1,
R.sub.2=

##STR00002##

where
R.sub.3 and R.sub.4 independently of one another =H, (CH.sub.2).sub.mY,
where Y=OH, CO.sub.2H, NH.sub.2, or Br, and m=0 to 4,
with the exception of R.sub.3=R.sub.4=H,
directly to the surface (O) and its activation to carbene formation, and/or (ii) the coating composition (A) comprises the carbene-forming compound (C), which is activated to carbene formation following application of the coating composition (A). The invention also relates to coatings produced by means of the method, and to coated plastics substrates.

[Purpose] Among two-component top coat paints for the automobile coatings field, wherein the base resin paint is circulated from a main tank with a pump upstream of the coating gun, and mixing and coating are effected using a curing agent supplied from a nitrogen-sealed tank and a two-component mixing device, to provide a paint composition with which problems such as thickening and gelling of the circulating base resin paint do not occur, coating is possible with a stabilized constant coating viscosity, and with which the paint film after stoving exhibits excellent Scratch resistance, stain resistance, acid resistance and gasoline resistance, and a multilayer coating formation method using this. [Solution] The present invention provides a two-component paint composition which is applied directly after mixing a base resin and a curing agent, wherein the base resin (A) contains a hydroxy group-containing acrylic resin (A-1) and a curing catalyst (A-2) as essential components, the curing agent (B) contains an isocyanate Compound (B-1) and an alkoxysilyl group-containing copolymer (B-2) as essential components, the aforesaid hydroxy group-containing acrylic resin (A-1) has a hydroxyl value of 80 to 180 mg KOH/g, a glass transition temperature of -40 to 40 C., and a weight average molecular weight of 2,000 to 20,000 g/mol, the aforesaid alkoxysilyl group-containing copolymer (B-2) is a copolymer obtained by copolymerizing 30 to 80 parts by weight of a vinylic monomer containing alkoxysilyl groups and 20 to 70 parts by weight of other copolymerizable monomers, its weight average molecular weight is 2,000 to 20,000 g/mol, and it does not contain hydroxy groups, carboxyl groups or amino groups which react with isocyanate groups.

A coating composition includes a flexible hyperbranched polyol preparable by (a) reacting a polyol comprising at least three hydroxyl groups with an aliphatic dicarboxylic acid having from 6 to 36 carbon atoms or an esterifiable derivative of the aliphatic dicarboxylic acid to form a hydroxyl-functional first intermediate product; (b) reacting the first intermediate product with a cyclic carboxylic acid anhydride to form a carboxylic acid-functional second intermediate product; and (c) reacting the second intermediate product with an epoxide-functional compound having one epoxide group to form the hyperbranched polyol. The coating composition may be cured to a coating layer having excellent flexibility.

A process for the production of an OEM base coat/clear top coat multi-layer coating wherein a waterborne base coat composition is spray-applied by electrostatically-assisted high speed rotary atomization, wherein the waterborne base coat composition comprises binder solids comprising about 20 to about 100 wt. % of an aqueously dispersed polyurethane urea resin with a carboxyl number of about 10 to 50 mg KOH/g.

A spot repair method of scratch-resistant paint film: (a) sanding a part to be repaired having a scratch-resistant clear paint film thereon, (b) sanding a part to be clear gradation painted outside the part to be repaired with an abrasive material, (c) painting the part to be repaired with a color base-paint, (d) applying a clear paint wet-on-wet without curing the color base-paint, (e) applying a clear paint diluted with a gradation agent to the part to be gradation painted, (f) drying the applied paints, and (g) polishing the dried parts, wherein (1) the clear paint is a two-liquid type having an isocyanate curing agent and (2) the gradation agent comprises from 5 to 50 mass % ethyl ethoxypropionate, from 1 to 5 mass % of an acrylic resin as solid fraction, a surfactant and a curing catalyst.

Described herein are an aqueous coating composition including at least one anionically stabilized binder, effect pigment, polycarboxylic acid, and solvent, and a method for producing a multicoat paint system by producing a basecoat directly on a substrate, producing a clearcoat directly on the basecoat, and then jointly curing the basecoat and the clearcoat. At least one of the basecoat materials includes the aqueous coating. Also described herein are multicoat paint system obtainable by this method, and the use of at least one polycarboxylic acid in an aqueous coating composition for improving the effect pigment orientation, or for color matching.

Disclosed herein is a tinted clearcoat composition including at least one binder resin (A) having functional groups (i), at least one curing agent (B) having functional groups (ii) being reactive with the functional groups (i), and at least one pigment (C), where the tinted clearcoat composition (TCC) is produced by (a) providing a clearcoat system (CS) including at least one binder resin (A) and at least one curing agent (B), (b) providing constituents of at least one pigment premixture (PP) including at least one pigment (C), (c) combining all or part of the clearcoat system (CS) with the constituents of the at least one pigment premixture (PP), (d) milling the mixture obtained in step (c), and (e) mixing, if applicable, the mixture obtained in step (d) with any yet missing parts of the tinted clearcoat composition (TCC).

The present invention relates to a pigmented aqueous basecoat material comprising a polyether-based reaction product which is preparable by reaction of (a) at least one compound of the formula (I)

X.sub.1-Y-X.sub.2(I)

in which
X.sub.1 and X.sub.2, independently of one another, are each a functional group which is reactive toward hydroxyl groups, and Y is a divalent aliphatic or araliphatic, carboxy-functional organic radical having a number-average molecular weight of 100 to 1000 g/mol, with
(b) at least one polyether of the general structural formula (II)

##STR00001##

in which
R is a C.sub.3 to C.sub.6 alkylene radical and n is selected accordingly such that the polyether (b) possesses a number-average molecular weight of 200 to 4000 g/mol, where components (a) and (b) are used in the reaction in a molar ratio of 0.7/2.3 to 1.6/1.7 and the resulting reaction product possesses a number-average molecular weight of 500 to 15 000 g/mol and an acid number of 10 to 120 mg KOH/g.

An object of the present invention is to provide a method for forming a multilayer coating film, the method making it possible to obtain, with excellent curability at low temperatures and in a short period of time, a multilayer coating film exhibiting an excellent finished appearance. The present invention provides a method for forming a multilayer coating film, wherein a substrate is sequentially coated with at least one layer of one or more base coating compositions, and with one or more clear coating compositions, the method being characterized by utilizing a clear coating composition containing a hydroxy-containing acrylic resin (A) having a hydroxy value in a specific range; a polyisocyanate compound (B) having a viscosity in a specific range; and an organometallic catalyst (C) containing a metallic compound (C1) in which the metal is a member selected from the group consisting of zinc, tin, zirconium, bismuth, lead, cobalt, manganese, titanium, aluminum, and molybdenum, and an amidine compound (C2).