JPH0328277A - Metallic paint composition - Google Patents

Abstract

PURPOSE:To obtain the subject composition which produces a pearly luster similar to that of a mica-filled coating by incorporating melamine cyanurate into a clear layer. CONSTITUTION:Melamine cyanurate (a white crystalline compound produced by mixing an aqueous melamine solution with an aqueous isocyanuric acid solution in an equimolar ratio) is incorporated into a clear layer.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a metallic paint that is often used for painting cars and the like. Conventional technology Metallic painting consists of dispersing aluminum pigment into clear paint and forming a clear layer on top of it.The light is reflected by the aluminum powder, giving it a sparkling appearance.
This is a phenomenon called the sparkling effect, which creates a beautiful appearance. In contrast, a coating method called Myriki Painting has been developed to give the painted surface a pearlescent finish. Mica paint is said to be the third-class automotive top coat after solid colors and metallic colors. (New Material Utilization Series, High Performance Paints, Edited by the High Performance Paints Editorial Committee, Published by Kogyo Research Association, 1988) Mica paint has a clear coating when light hits the added mica (mica) dispersed in the clear coating.
Since some of the light is transmitted and some of the light is reflected, it produces a pearlescent luster, giving it an aesthetic appearance not found in metallic paints.

Problems to be Solved by the Invention There are two types of mica coating for automobiles: a three-coat method and a two-coat method. In the 3-coat method, first paint a solid undercolor as a base color, then finish with mica base and clear. In addition, the two-coat method is similar to conventional metallic painting, in which primary colors and mica base are mixed and painted, and then a clear coat is applied to finish.

Mica paint has a superior aesthetic appearance compared to metallic paint, and there is strong user demand for it, but there are many problems such as the mica pigment being expensive and repair being difficult.

Means for Solving the Problems In view of the above circumstances, the inventors of the present invention have conducted intensive research and have found the following.
We completed the present invention by discovering that by dispersing melamine cyanurate in the clear layer of metallic paint to form a paint film, a pearlescent luster similar to mica paint can be produced. The melamine cyanurate used in the present invention is a white crystal compound produced by mixing an aqueous solution of melamine and an aqueous solution of isocyanuric acid in an equimolar ratio, and is a compound of white crystals in which melamine and isocyanuric acid are mixed in a planar shape. are connected by hydrogen bonds and have a layered structure. Melamine cyanurate is a substance that is insoluble in general organic solvents and slightly soluble in water, and is used as a flame retardant for nylon resins, a lubricant, etc.

Metallic painting involves applying an undercoat on the substrate in the usual way, applying an aluminum color containing non-roofing type aluminum powder on top of that, and finally applying a clear coat. 0.01 to 0.01 of cyanurate in terms of solid content during painting
A coating film containing 1.0%, preferably 0.602 to 0.5%, should be applied. A part of the incident light passes through the clear layer, reaches the metallic layer, is reflected by the aluminum surface, and enters the clear layer.
The melamine cyanurate in the layer causes complex refraction,
It is estimated that it exhibits pearlescent luster. The refractive index of acrylic paint used for car painting is 1.49 to 1.5.
9, but the refractive index of melamine cyanurate is about 2.
．． 60, and it is thought that this difference in refractive index produces pearlescent luster.

The phenomenon in which a coating film containing melamine cyanurate exhibits a pearlescent luster can be easily observed by simply placing a hardened resin plate with dispersed melamine cyanurate on top of aluminum foil.

Example 1 To 100 parts by weight of epoxy resin Epicor #828 (manufactured by Yuka Ciel Eboxy ■), 0.00 parts by weight of melamine cyanurate was added.
Thoroughly disperse 1 part by weight using a three-roll mill.

Add an acid anhydride curing agent (product name: Rikacid M) to the mixture.
88 parts by weight of 1-benzyl-2-phenylimitasol hydrochloride as a curing accelerator were added, stirred well, and degassed. The resulting mixture was poured between two glass plates with a gap of 3 ffiIl, heated at a temperature of 100"C for 2 hours, and then heated to 120"C for 2 hours to cure.

Next, when the cured product containing melamine cyanurate and the transparent cured product cured using only epoxy resin, curing agent, and curing accelerator were placed side by side on a piece of aluminum foil for cooking, the epoxy resin cured with the addition of melagon cyanurate was placed side by side on a sheet of aluminum foil for cooking. In the case of the resin cured product, the aluminum foil had a pearlescent luster, but in the case of the transparent cured product, the color of the aluminum foil was observed as is. Example 2 A commercially available metallic color automotive repair spray paint was applied to a 0.8 m steel plate and dried to obtain a cured coating.
Next, melamine cyanurate was added to a clear paint consisting of styrene, methyl meccrylate, butyl acrylate, etc. in an amount of 0.1% by weight in terms of solid content, and the mixture was mixed in a ball ξ to form a paint.

This paint was applied to the top surface of the coated steel plate using a sub gun.

Claims (1)

[Claims] (1) A metallic paint composition characterized in that the clear layer contains melamine cyanurate.