An object to be solved by the present invention is to provide a multilayer coating film forming method by which a multilayer coating film having reduced nonuniformity and exhibiting excellent luster and high flip-flop properties can be formed. The present invention provides a multilayer coating film forming method characterized by including: applying an aqueous first colored paint (X) containing a color pigment (x1) and an effect pigment (x2) on an object to be coated to form a first colored coating film; applying an aqueous second colored paint (Y) containing a viscosity modifier (y1), a color pigment (y2), and an effect pigment (y3) to form a second colored coating film; applying a clear paint (Z) to form a clear coating film; and curing by heating, wherein a solid content of the aqueous second colored paint (Y) is in a range of 0.1 to 6 mass %, an average value of light transmittance of the second colored coating film is 1% or lower, and a difference |R(X)−R(S)| between an average value of light reflectance of the first colored coating film and an average value of light reflectance of the multilayer coating film is 5% or lower.

Disclosed herein is a method of preparing a multilayer coating system on a substrate including a step of applying at least one organic black pigment containing basecoat composition to a substrate and forming a first coating film thereon (1), optionally subsequently applying a second basecoat composition and forming a second coating film adjacent to the first coating film (2), and applying a pigmented topcoat composition to the first coating film in case optional step (2) is not performed (3a), or applying a clearcoat composition to the second coating film in case optional step (2) is performed, and where steps (1), (2) and (3b) are performed, or steps (1) and (3a) are performed, includes at least one non-black coloring pigment having a volume average particle size of <1000 nm in an amount in the range of from 0.01 to 7.50 wt.-%, based on its total solid content.

Provided is a method for forming a multilayer coating film that is capable of forming a multilayer coating film that has pearly luster with excellent blackness and high reflectance of an infrared laser. The method for forming a multilayer coating film includes applying a carbon black pigment-containing first colored paint (X) to form a first colored coating film; applying a second colored paint (Y) containing a pigment (A) that is a transparent or translucent base material coated with a metal oxide to form a second colored coating film; applying a clear paint (Z) to form a clear coating film; and heating the first colored coating film, the second colored coating film, and the clear coating film separately or simultaneously to cure these films, wherein the first colored coating film has a lightness L*(45°) of less than 20, the multilayer coating film has a lightness L*(45°) of less than 20, and the multilayer coating film has a diffuse reflectance of 10% or more at a wavelength of 905 nm.

Disclosed herein is a method for producing an aqueous titanium dioxide slurry. The method includes (a) providing an aqueous dispersion medium, and (b) dispersing titanium dioxide into the aqueous dispersion medium provided in step (a) to obtain a titanium dioxide slurry containing at least 65 wt.-% up to 85 wt.-% of titanium dioxide, based on the total weight of the thus obtained slurry, where step (b) is carried out by sole use of a non-milling mixing device and at least until the Hegman fineness of the titanium dioxide particles is below 8 μm. Further disclosed herein are a slurry obtained from the disclosed method, a coating composition containing the same, and a method for producing a coating and a thus coated substrate.

Described herein is a process for producing a multilayer coating onto a fiber-reinforced composite material. Also described herein is a fiber-reinforced composite material coated with a multilayer coating obtainable by this process.

Described herein is a curable coating composition including at least one Michael donor (A) having at least one acetoacetate group, at least one Michael acceptor (B) and at least one specific catalyst (C). Also described herein are a method of using the curable coating composition as a clear coating in a method to prepare a multilayer coating and a multilayer coating obtained from said process. Further described herein is a kit-of-parts including at least two separate containers C1 and C2, where the specific catalyst (C) and/or the at least one Michael acceptor (B) is contained in container C2. Additionally described herein is a method of using specific salts of carboxylic acids as catalyst in a reaction between a Michael donor (A) having at least one acetoacetate group and a Michael acceptor (B).

Described herein are a curable coating composition including at least one Michael donor (A) having at least one thiol group, at least one Michael acceptor (B) and at least one specific catalyst (C), a method of using the curable coating composition as a clear coating in a process to prepare a multilayer coating and a multilayer coating obtained from said process. Also described herein is a kit-of-parts including at least two separate containers C1 and C2, where the specific catalyst (C) is contained in container C1 and/or C2. Finally, described herein is a method of using specific salts of carboxylic acids as catalyst in a reaction between a Michael donor (A) having at least one thiol group and a Michael acceptor (B).

A multilayer coating film forming method to form a multilayer coating film having a glittering appearance. Forming a multilayer coating film by sequentially applying, on top of a base material, a first base coating material, a second base coating material, and a clear coating material in a wet-on-wet process, wherein: the first base coating material is a transparent or colored coating material; the second coating material contains a flaky lustrous pigment; the amount of flaky lustrous pigment being 10-60 parts by mass to 100 parts by mass of resin solid content in the second base coating material, and the concentration of solids in the coating falls being 5-20 mass % with respect to the total mass of the second base coating material; and the thickness of a coating film obtained from the second base coating material falls being 1-8 μm on the basis of the coating film when cured.

A laminate containing a metallic base layer and a transparent colored layer formed on the metallic base layer. The metallic base layer contains an aluminum pigment, a light-scattering component, a surface adjusting agent, and a rheology control agent, the aluminum pigment being present in an amount of 15 to 70 parts by mass, on a solids basis; and the light-scattering component being present in an amount of 5 to 55 parts by mass, on a solids basis, based on 100 parts by mass of the metallic base layer. The transparent colored layer contains a resin component, a curing agent, and a color pigment, the color pigment being present in an amount of 0.5 to 10 parts by mass, based on 100 parts by mass of the resin solids content of the transparent colored layer.

A method for forming a multilayer coating film, sequentially conducting step (1) of applying an aqueous 2-package type first colored paint on both a metal member and a plastic member of an automobile outer panel to form an uncured first colored coating film; step (2) of applying an aqueous 1-package type white paint on the uncured first colored coating film by step (1) to form an uncured white coating film; step (3) of applying an aqueous 1-package type interference color paint on the uncured white coating film by step (2) to form an uncured interference color coating film; step (4) of applying a solvent-based 2-package type clear paint on the uncured interference color coating film by step (3) to form an uncured clear coating film; and step (5) of heating these coating films by steps (1) to (4) at 75 to 100° C. to simultaneously cure them.