JP7623155B2 - Shiny coated product and its manufacturing method - Google Patents

Description

The present invention relates to a glittering coated article in which a glittering coating film containing a glittering pigment is provided on the surface of a substrate, and a method for producing the glittering coated article.

Conventionally, glitter coatings in which glitter coating films containing glitter pigments are provided on the surface of a substrate have been widely used. Glitter pigments have a strong glittering feel and a particulate feel (a glossy feel that appears to sparkle), and are known as pigments that impart a pearlescent luster to coating films. Known glittering pigments include those in which a titanium oxide layer is provided on the surface of scaly materials such as mica, scaly alumina, and scaly glass flakes (see Patent Document 1). However, there is a demand for designs that have a more luxurious feel, with no particulate feel and a silky feel (a silky smooth shine). Flake titanic acid is known as a glittering pigment that provides such a silky feel.

For example, the following Patent Document 2 discloses flaky titanic acid obtained by treating a titanate having a layered crystal structure with an acid and then reacting it with an organic basic compound to swell or peel off the interlayers. The flaky titanic acid is said to have an average major axis of 5 μm to 30 μm and an average thickness of 0.5 nm to 300 nm.

JP 2003-225610 A JP 2006-257179 A

However, although the glitter pigment made of flaky titanic acid in Patent Document 2 has a silky feel without a grainy feel, there is a problem in that the water-resistant adhesion is insufficient when it is made into a coating film.

On the other hand, when giving a paint film a silky feel and color, a method of blending color pigments is used. However, there are problems with this method, such as color variation depending on the dispersion degree of the color pigment, and deterioration of the paint film due to discoloration of the color pigment.

The object of the present invention is to provide a glittering coating that is free of a grainy feel, has an excellent silky feel, has excellent water-resistant adhesion, and exhibits a pale blue (sky blue) color due to scattered light even without the addition of a coloring pigment, and a method for producing the glittering coating.

The present invention provides the following glittering coated article and a method for producing the glittering coated article.

Item 1: A glittering coated article comprising a substrate and a glittering coating film provided on the surface of the substrate, the glittering coating film containing a glittering pigment and a polymeric compound having a basic group or a salt thereof, the glittering pigment being flaky titanic acid having an average thickness of 20 nm or more and 60 nm or less.

Item 2. The glittering coated article according to item 1, wherein the L ^* value of the substrate surface in the L ^* c ^* h color system is less than 40.

Item 3: The flaky titanic acid is a flaky titanic acid obtained by treating titanic acid having a layered crystal structure with a polymeric compound or a salt thereof having a basic group in an amount of more than 0.1 equivalent and less than 0.5 equivalent relative to the exchangeable ion capacity of the titanic acid, thereby swelling and peeling the interlayers in the layered crystal structure. The lustrous coated article according to item 1 or 2.

Item 4. The glittering coating according to any one of items 1 to 3, wherein the polymer compound having a basic group or a salt thereof is an amino-modified silicone.

Item 5. The glittering coating described in any one of items 1 to 4, wherein the average long diameter of the flaky titanic acid is 5 μm or more and 30 μm or less.

Item 6: The glittering coating according to any one of items 1 to 5, wherein the glittering pigment content in the glittering coating is 1% by mass or more and 40% by mass or less in terms of pigment concentration (PWC).

Item 7: The glittering coating according to any one of items 1 to 6, wherein the glittering coating further contains a polysaccharide derivative, and the polysaccharide derivative is formed by substituting at least a portion of the hydrogen atoms in the hydroxyl groups contained in the polysaccharide with organic groups.

Item 8. The glittering coating according to item 7, wherein the organic group is at least one selected from the group consisting of an alkyl group having a substituent, an alkyl group having no substituent, an acyl group having a substituent, and an acyl group having no substituent.

Item 9. The glittering coating according to item 7 or 8, wherein the polysaccharide is cellulose.

Item 10. The photoluminescent coating according to any one of items 7 to 9, wherein the mass ratio of the photoluminescent pigment to the polysaccharide derivative (photoluminescent pigment/polysaccharide derivative) is 5/95 or more and 50/50 or less.

Item 11. The glittering coating according to any one of items 1 to 10, wherein the glittering coating has a thickness of 10 μm or more and 150 μm or less.

Item 12: A method for producing a glittering coated article according to any one of items 1 to 11, comprising the steps of preparing a glittering pigment composition containing a glittering pigment, a polymeric compound having a basic group or a salt thereof, and a solvent, and applying the glittering pigment composition to a substrate to form a glittering coating film.

Item 13: The method for producing a glittering coated article according to Item 12, wherein the glittering pigment composition further contains a polysaccharide derivative.

The present invention provides a glittering coating that is free of a grainy feel, has an excellent silky feel, has excellent water-resistant adhesion, and exhibits a pale blue (sky blue) color due to scattered light without the addition of a coloring pigment, as well as a method for producing the glittering coating.

FIG. 1 is a schematic cross-sectional view showing a glittering coated article according to one embodiment of the present invention. FIG. 2 is a cross-sectional photograph showing an example of a glittering coating film provided on a glittering coated article of the present invention. FIG. 3 is a schematic diagram for explaining an example of the mechanism of exfoliation in a titanate having a layered crystal structure. FIG. 4 is a cross-sectional photograph showing an example of a void (space) formed in a glittering coating film.

The following describes an example of a preferred embodiment of the present invention. However, the following embodiment is merely an example. The present invention is not limited to the following embodiment.

[Glossy coating]
Fig. 1 is a schematic cross-sectional view showing a glittering coated article according to one embodiment of the present invention. As shown in Fig. 1, the glittering coated article 1 includes a substrate 2 and a glittering coating film 3.

A glittering coating film 3 is provided on the surface 2a of the substrate 2. The glittering coating film 3 contains a glittering pigment and a polymeric compound having a basic group or a salt thereof. The glittering pigment is a flaky titanic acid having an average thickness of 20 nm or more and 60 nm or less.

The glittering coating 1 of this embodiment has the above-mentioned configuration, so it has no grainy feel, has an excellent silky feel, has excellent water-resistant adhesion, and can show a pale blue (sky blue) color due to scattered light without the addition of color pigments.

Conventionally, glittering pigments made of flaky titanic acid have had the problem that the water-resistant adhesion of the coating film is insufficient due to the presence of many voids (air gaps) as shown in Figure 4. On the other hand, when a color pigment is added to the coating film to give it a silky feel and color, there are problems in that the color varies depending on the dispersion degree of the color pigment, and the color of the coating film deteriorates due to discoloration of the color pigment.

In response to this, the inventors have discovered that by setting the average thickness of the flaky titanic acid as the glittering pigment contained in the glittering coating film 3 to 20 nm or more and 60 nm or less, it is possible to achieve a pale blue (sky blue) color without incorporating a coloring pigment. In this regard, it is believed that by setting the average thickness of the flaky titanic acid to about 1/10 of the visible light wavelength, the glittering coating film 3 is made to appear pale blue (sky blue) due to Rayleigh scattering.

The inventors have also discovered that water-resistant adhesion can be improved by forming the glittering coating film 3 to contain a polymeric compound having a basic group or a salt thereof in addition to the glittering pigment as described above.

In particular, when a polymeric compound having a basic group or its salt is used, the flaky titanic acid can be neatly oriented in the coating film, as shown in Figure 2, which further improves the silky feel and water-resistant adhesion.

The glittering coating 1 of this embodiment therefore has no grainy feel, has an excellent silky feel, has excellent water-resistant adhesion, and can show a pale blue (sky blue) color due to scattered light without the addition of a coloring pigment.

Such a glossy coated object 1 can be suitably used in automobiles, household electrical appliances, office automation equipment, etc.

In the above embodiment, the glossy coating film 3 is provided only on one surface 2a of the substrate 2, but the glossy coating film 3 may be provided on both surfaces 2a and 2b of the substrate 2.

The following describes in detail each component of the glossy coated article of the present invention, such as glossy coated article 1.

(Substrate)
Examples of the material of the substrate include metal materials such as steel, aluminum, brass, copper, stainless steel, tinplate, zinc-plated steel, and alloyed zinc (Zn-Al, Zn-Ni, Zn-Fe, etc.) plated steel; polyolefin resins such as polyethylene and polypropylene; thermoplastic polyester resins such as polyethylene terephthalate resin, polybutylene terephthalate (PBT) resin, polycarbonate (PC) resin, and polycarbonate-polybutylene terephthalate (PC/PBT) resin; styrene resins such as acrylonitrile-styrene resin, acrylonitrile-butadiene-styrene (ABS) resin, and acrylonitrile-styrene-acrylate (ASA) resin; polymethyl methacrylate resin, acrylic resin, vinylidene chloride, polyamide resin, polyphenylene ether resin, polyoxymethylene resin, polyurethane resin, epoxy resin, and the like, or hybrid resins thereof and fiber-reinforced plastics (Fiber-Reinforced Plastics). Examples of the substrate include plastic materials (synthetic resin molded products) such as plastics and engineering resins; inorganic materials such as glass cement and concrete; wood; and fiber materials (paper, cloth, etc.). Depending on the material, these can be degreased or surface-treated as appropriate to prepare a substrate. Furthermore, the above-mentioned substrates can also be coated with an undercoat coating film or an intermediate coating film.

The above-mentioned undercoat coating film is formed to conceal the surface of the material and to provide the material with anti-corrosion and anti-rust properties, and can be obtained by applying an undercoat paint, drying, and curing. There are no particular limitations on the undercoat paint, and examples of the undercoat paint include electrocoating paint and solvent-based primer.

The intermediate coating film is formed to conceal the surface of the material or the undercoat coating film, and to impart adhesion, chipping resistance, etc., and can be obtained by applying an intermediate coating paint to the surface of the material or the undercoat coating film, and then drying and curing the intermediate coating paint. There are no particular limitations on the intermediate coating paint, and for example, organic solvent-based or water-based intermediate coating paints containing a thermosetting resin composition and a coloring material (pigment, dye, etc.) can be preferably used.

The L ^* value of the substrate surface in the L ^* c ^* h color system is preferably less than 40, more preferably 30 or less, and even more preferably 20 or less. When the L ^* value of the substrate surface is less than the upper limit or equal to or less than the upper limit, the transmitted light can be absorbed more, and the pale blue color exhibited by the scattered light can be made more prominent. The lower limit of the L ^* value of the substrate surface is not particularly limited, and can be, for example, 1.

From the viewpoint of further reducing the L ^* value of the substrate surface, the substrate is preferably a black substrate, although the substrate may be a white substrate and the color of the substrate is not particularly limited.

(Brilliant coating film)
The glittering coating film contains a glittering pigment and a polymeric compound having a basic group or a salt thereof. The glittering coating film may further contain a polysaccharide derivative. In this case, the water-resistant adhesion can be further improved.

The thickness of the glittering coating film is preferably 10 μm or more, more preferably 15 μm or more, even more preferably 20 μm or more, and preferably 150 μm or less, more preferably 100 μm or less, and even more preferably 50 μm or less. When the thickness of the glittering coating film is within the above range, there is no grainy feel, and the film has a more excellent silky feel, and the pale blue color (sky blue) that is produced by scattered light can be made to stand out even more.

Luster pigments;
Flaky titanic acid as a luster pigment can be obtained, for example, by reacting titanic acid having a layered crystal structure with a polymeric compound or a salt thereof having a basic group in an amount greater than 0.1 equivalent and less than 0.5 equivalent relative to the exchangeable ion capacity of the titanic acid, thereby swelling and peeling off the spaces between the layers in the layered crystal structure.

Titanic acid with a layered crystal structure (hereinafter referred to as layered titanic acid) can be obtained, for example, by treating titanate with a layered crystal structure (hereinafter referred to as layered titanate) with an acid and replacing the exchangeable metal cations with hydrogen ions or hydronium ions.

The acid used in the acid treatment is not particularly limited, and may be a mineral acid such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, or boric acid, or an organic acid. The type of layered titanic acid, the type and concentration of the acid, and the slurry concentration of the layered titanic acid affect the exchange rate of metal cations. In general, the lower the acid concentration and the higher the slurry concentration, the greater the amount of remaining interlayer metal cations, making it more difficult for the layers to peel off, and therefore the greater the average thickness of the flaky titanic acid after peeling.

If metal cations are difficult to remove, the acid treatment may be repeated as necessary.

An example of the layered titanate used as the raw material is _{Cs0.7Ti1.83O4} obtained by mixing cesium carbonate and titanium dioxide in a molar ratio of 1:5.3 and firing at 800°C according to the method disclosed in Japanese Patent _{No. 2979132} .

Also included is K0.8L0.27Ti1.73O4, which is obtained by mixing potassium carbonate, lithium carbonate, and titanium dioxide in a molar ratio of K/Li/Ti = 3/1/6.5, grinding the mixture, and firing it at ₈₀₀ °C according to the method disclosed in _{WO99 / 11574} .

Also included is a layered titanate represented by the general formula A X M Y □ Z Ti 2-(Y+Z) O 4 [wherein A _{and M} represent different monovalent to trivalent metals, □ represents a defective site of Ti, X is a positive real number satisfying 0<X<1.0, and Y and _Z are 0 or positive real numbers satisfying 0< _Y+Z < ₁ ], obtained by using an alkali metal or an alkali metal halide or sulfate as a flux and mixing the mixture so that the mass ratio of flux/raw material is 0.1 to 2.0 according to the method disclosed in Japanese Patent No. 3062497, and firing the mixture at 700°C to 1200°C.

In the above general formula, A is a metal having a valence of monovalent to trivalent, preferably at least one selected from the group consisting of K, Rb, and Cs. M is a metal having a valence of monovalent to trivalent different from metal A, preferably at least one selected from the group consisting of Li, Mg, Zn, Cu, Fe, Al, Ga, Mn, and Ni.

Specific examples include K _0.80 Li _0.27 Ti _1.73 O ₄ , Rb _0.75 Ti _1.75 Li _0.25 O ₄ , Cs _0.70 Li _0.23 Ti _1.77 O ₄ , Cs _0.70 □ _0.18 Ti _1.83 O ₄ , Cs _0.70 Mg _0.35 Ti _1.65 O ₄ , K _0.8 Mg _0.4 Ti _1.6 O ₄ , K _0.8 Ni _0.4 Ti _1.6 O ₄ , K _{0 .8} Zn _0.4 Ti _1.6 O ₄ , K _0.8 Cu _0.4 Ti _1.6 O _{4 , K0.8Fe0.8Ti1.2O4 , K0.8Mn0.8Ti1.2O4 , K0.76Li0.22Mg0.05Ti1.73O4 , ​ ​ ​ ​ ​ ​ K0.67Li0.2Al0.07Ti1.73O4 and the like .}

Alternatively, K _0.5-0.7 L _0.27 Ti _1.73 O _3.85-3.95 obtained by pickling K _0.8 L _0.27 Ti _1.73 O ₄ and then firing it according to the method disclosed in WO 03/037797 may be used.

Flake-like titanic acid can be obtained by treating a layered titanate with an acid to obtain layered titanic acid, and then reacting it with a polymeric compound or its salt having a basic group in an amount of more than 0.1 equivalent and less than 0.5 equivalent relative to the exchangeable ion capacity of the layered titanic acid to swell and peel off the interlayers in the layered crystal structure.

The average long diameter of the flaky titanic acid is preferably 5 μm or more, more preferably 10 μm or more, preferably 30 μm or less, and even more preferably 25 μm or less. When the average long diameter of the flaky titanic acid is equal to or greater than the above lower limit, the silky feel can be further improved. On the other hand, when the average long diameter of the flaky titanic acid is equal to or less than the above upper limit, the flaky titanic acid can be dispersed more uniformly and parallelly in the coating film.

The average long diameter of flaky titanic acid refers to the particle size in the plane direction perpendicular to the thickness direction of the flaky titanic acid. The average long diameter can be measured, for example, by observation with a transmission electron microscope (TEM) or a scanning electron microscope (SEM). Specifically, it can be measured by blending flaky titanic acid into a coating film and observing the cross section of the coating film with a TEM. The average long diameter can be, for example, the average particle diameter of 100 flaky titanic acid particles measured in this way.

The average thickness of the flaky titanic acid is preferably 30 nm or more, more preferably 35 nm or more, and is preferably 55 nm or less, more preferably 50 nm or less. When the average thickness of the flaky titanic acid is within the above range, the pale blue color exhibited by scattered light can be made even more prominent.

The average thickness of the flaky titanic acid can be measured by observation using a transmission electron microscope (TEM) or a scanning electron microscope (SEM). Specifically, the average thickness can be measured by blending flaky titanic acid into a coating film and observing the cross section of the coating film using a TEM. The average thickness can be, for example, the average thickness of 100 flaky titanic acid particles measured in this manner.

The flaky titanic acid is preferably a single-layer titanic acid nanosheet in which the layered titanic acid is completely peeled off, but may also be a laminate of 2 to 300 layers of titanic acid nanosheets. The laminate of titanic acid nanosheets is preferably a laminate of 10 to 300 layers of titanic acid nanosheets. In addition, a mixture of single-layer titanic acid nanosheets and laminates of titanic acid nanosheets may be used. In this case, however, it is desirable that the mixture be such that the average thickness of the flaky titanic acid is within the above-mentioned range.

The content of the glittering pigment in the glittering coating is preferably 1% by mass or more, more preferably 5% by mass or more, and preferably 40% by mass or less, more preferably 35% by mass or less, in terms of pigment concentration (PWC). When the glittering pigment content is within the above range, a more excellent silky feel can be obtained, and the pale blue color exhibited by scattered light can be made to stand out even more.

A polymeric compound having a basic group or a salt thereof;
The polymer compound or salt thereof having a basic group is not particularly limited as long as it is a polymer compound having an interlayer swelling effect of titanic acid having a layered crystal structure. The basic group is preferably a primary to tertiary amino group in view of availability of raw materials and ease of synthesis.

Examples of polymer compounds having a basic group or salts thereof include (meth)acrylic polymers having a basic group, amino-modified silicones, etc., and preferably amino-modified silicones. In this specification, "(meth)acrylic" means "at least one of acrylic and methacrylic." The polymer compounds having a basic group or salts thereof may be used alone or in combination.

The amino-modified silicone has a polysiloxane skeleton consisting of repeating (-Si-O-) units, and a part of the alkyl side chain of the silicon atom is modified with an amino-modified group. The amino-modified group may be bonded to a side chain of the silicone main chain, or may be bonded to an end. Examples of the amino-modified group include primary to tertiary amino groups, and organic groups having primary to tertiary amino groups. Examples of the organic group having a primary to tertiary amino group include -R ¹ -NH ₂ (R ¹ represents a divalent organic group). Among these, a compound represented by the following formula (1) is preferred.

(In formula (1), ^R2 represents _-NH2 or ^-R1 - _NH2 , a plurality of ^R2 may be the same or different, and n represents any integer. ^R1 represents a divalent organic group.)

n is preferably an integer from 1 to 2,000.

The divalent organic group for R ¹ includes an alkylene group, an arenediyl group, and the like.

The alkylene group is preferably an alkylene group having 1 to 10 carbon atoms. Examples of such alkylene groups include a methylene group, an ethylene group, and a propylene group.

As the arenediyl group, an arenediyl group having 6 to 10 carbon atoms is preferred. Examples of such arenediyl groups include a phenylene group.

The amino-modified silicone preferably has a kinetic viscosity at 25° C. of 10 mm ² /s to 2000 mm ² /s, more preferably 15 mm ² /s to 600 mm ² /s, and even more preferably 20 mm ² /s to 100 mm ² /s. If the kinetic viscosity is less than 10 mm ² /s or more than 2000 mm ² /s, it becomes difficult to disperse in an organic solvent. The kinetic viscosity can be measured with a kinetic viscosity measuring device.

The functional group equivalent (amino equivalent) of the amino-modified silicone is preferably 50 g/mol to 100,000 g/mol, more preferably 300 g/mol to 3,000 g/mol, and even more preferably 1,000 g/mol to 2,000 g/mol. By setting the functional group equivalent within the above range, the degree of peeling can be further increased and the dispersion stability in organic solvents can be further improved.

The amino-modified silicone is preferably water-insoluble. Water-insoluble means that the amount dissolved in 1 L of water at 25°C is 10 g or less.

As an example of the amino-modified silicone, there can be mentioned a double-ended amino-modified silicone shown in the following formula (2). In formula (2), R is a methylene group, a phenylene group, or the like.

A single type of amino-modified silicone may be used, or a mixture of two or more types may be used.

The content of the polymer compound having a basic group or its salt is preferably 2% by mass or more, more preferably 5% by mass or more, even more preferably 8% by mass or more, preferably 50% by mass or less, more preferably 40% by mass or less, and even more preferably 30% by mass or less, based on 100% by mass of the solid content of the glittering coating film (the glittering pigment composition constituting the glittering coating film). When the content of the polymer compound having a basic group or its salt is equal to or more than the above lower limit, the water-resistant adhesion can be further improved. When the content of the polymer compound having a basic group or its salt is equal to or less than the above upper limit, the silky feel can be further improved.

In order to apply a polymeric compound or its salt having a basic group with interlayer swelling properties, the polymeric compound or its salt having a basic group may be added directly, or a polymeric compound or its salt having a basic group diluted with water or an aqueous medium, to a dispersion in which layered titanic acid after acid treatment or hot water treatment is dispersed in an aqueous medium, while stirring.

The amount of the polymeric compound having a basic group or its salt to be blended is preferably more than 0.1 equivalent and less than 0.5 equivalent of the polymeric compound having a basic group or its salt relative to the exchangeable ion capacity of the layered titanic acid, and more preferably 0.2 equivalent or more and 0.4 equivalent or less. If the amount of the polymeric compound having a basic group or its salt to be blended is 0.1 equivalent or less relative to the exchangeable ion capacity of the layered titanic acid, delamination may not be expected. Also, if the amount of the polymeric compound having a basic group or its salt to be blended is 0.5 equivalent or more relative to the exchangeable ion capacity of the layered titanic acid, the development of a pale blue (sky blue) color due to scattered light may not be expected.

The exchangeable ion capacity is the amount of exchangeable metal ions, and for example, when the layered titanate is represented by the general formula _AxMy □ _{zTi2- (y+z) O4} , it refers to the value represented by mx+ _ny , where m is the valence of A and n is the valence of M. Furthermore, the equivalent weight refers to the amount of cationic groups generated by the reaction of a polymer compound or a salt thereof having a basic group with hydrogen ions or hydronium ions present in the layered titanate.

The average long diameter of the flaky titanic acid can be maintained at approximately the same level as that of the raw layered titanate unless strong shearing force is applied during the process of delaminating the layered titanate by applying 0.5 equivalents or more of a polymeric compound having a basic group or its salt to the layered titanate.

In the present invention, it is preferable that the polymer compound having a basic group or its salt is not a low molecular weight amine having a molecular weight of 500 or less, and it is preferable that the glossy coating film does not contain such a low molecular weight amine.

Polysaccharide derivatives;
The glittering coating film may further contain a polysaccharide derivative. In this case, the water-resistant adhesion can be further improved. This can be explained as follows.

When a hydrophobic amine 12 with a long hydrophobic portion as shown in FIG. 3 is used as a polymer compound having a basic group or its salt, the layered titanate 11 (titanate having a layered crystal structure) is swelled between the layers and peeled off, while imparting hydrophobicity to the surface of the flaky titanate 13. However, when such a polymer compound having a basic group or its salt is used as a peeling agent, it tends to aggregate after peeling in water and become a rice cake-like aggregate. In contrast, by including a polysaccharide derivative 14, the dispersibility of the layered titanate 11 can be increased even in an organic solvent, and thus the water-resistant adhesion can be further increased like a binder.

The polysaccharide derivative has a polysaccharide skeleton as the main skeleton, and is constructed by substituting at least a portion of the hydrogen atoms of the hydroxyl groups contained in the polysaccharide with organic groups.

The organic group may be an alkyl group having a substituent, an alkyl group having no substituent, an acyl group having a substituent, or an acyl group having no substituent. These organic groups may be used alone or in combination.

The alkyl group is preferably an alkyl group having 1 to 5 carbon atoms. Examples of such alkyl groups include a methyl group and an ethyl group. Examples of the substituents that the alkyl group may have include a hydroxy group and a carboxy group.

The acyl group is preferably an acyl group having 2 to 5 carbon atoms. Examples of such acyl groups include an acetyl group, a propionyl group, a butyryl group, and an isobutyl group.

Examples of polysaccharides include cellulose and starch. The polysaccharide is preferably cellulose. Cellulose is a linear polymer formed by polymerizing β-D-glucose molecules (β-D-glucopyranose) represented by the following formula (3) through β-1,4-glycosidic bonds. Each glucose unit that constitutes cellulose has three hydroxyl groups (m in the following formula (3) is a natural number).

Polysaccharide derivatives are those in which the organic groups have been introduced into such cellulose using the hydroxyl groups. Cellulose is the main component of plants, and can be obtained by separating and treating other components such as lignin from plants. In addition to those obtained in this way, cotton (e.g. cotton linters) and pulp (e.g. wood pulp) with a high cellulose content can be used either as is or after purification. The shape, size, and form of cellulose or its derivatives used as raw materials are preferably in the form of a powder with an appropriate particle size and shape, from the standpoints of reactivity, solid-liquid separation, and ease of handling.

The degree of polymerization of cellulose is preferably in the range of 50 to 5,000, expressed as the glucose polymerization degree (average polymerization degree). If the degree of polymerization is too low, the dispersion of the luster pigment may not be sufficient. Conversely, if the degree of polymerization is too high, compatibility with organic solvents may be impaired.

The average number of the organic groups introduced per glucose unit of cellulose (DS _LO ) (organic group introduction ratio), i.e., the average number of hydroxy groups substituted with the organic groups per glucose unit (hydroxyl group substitution degree), can be set appropriately depending on the physical properties required of the target bright pigment composition and on production efficiency, and can be set, for example, in the range of 0.1 to 2.9, preferably 1.8 to 2.8, and more preferably 2.3 to 2.7.

Polysaccharide derivatives include cellulose esters and cellulose ethers.

Specific examples of cellulose esters include cellulose acetates such as cellulose diacetate (DAC) and cellulose triacetate (TAC); cellulose C _3-5 acylates such as cellulose propionate and cellulose butyrate; and cellulose acylates such as cellulose acetate C _3-5 acylates such as cellulose acetate propionate (CAP) and cellulose acetate butyrate (CAB).

Examples of cellulose ethers include alkyl cellulose, hydroxyalkyl cellulose, hydroxyalkyl alkyl cellulose, carboxyalkyl cellulose, and alkyl-carboxyalkyl cellulose.

Examples of the alkyl cellulose include _C1-4 alkyl celluloses such as methyl cellulose and ethyl cellulose.

Examples of hydroxyalkyl cellulose include hydroxy C _2-4 alkyl celluloses such as hydroxyethyl cellulose (HEC) and hydroxypropyl cellulose (HPC).

Examples of the hydroxyalkyl alkyl cellulose include hydroxy C _2-4 alkyl C _1-4 alkyl cellulose such as hydroxypropyl methyl cellulose.

Examples of carboxyalkyl cellulose include carboxymethyl cellulose (CMC).

Examples of alkyl-carboxyalkyl cellulose include methyl carboxymethyl cellulose.

Among these, cellulose esters and cellulose ethers are preferred, with ethyl cellulose and cellulose acetate butyrate (CAB) being more preferred.

These polysaccharide derivatives may be used alone or in combination.

The content of the polysaccharide derivative is preferably 20% by mass or more, more preferably 30% by mass or more, even more preferably 45% by mass or more, preferably 95% by mass or less, more preferably 90% by mass or less, and even more preferably 85% by mass or less, based on 100% by mass of solids in the glittering coating film (the glittering pigment composition constituting the glittering coating film). When the content of the polysaccharide derivative is equal to or more than the lower limit, water-resistant adhesion can be further improved. When the content of the polysaccharide derivative is equal to or less than the upper limit, silkiness can be further improved.

The mass ratio of the luster pigment to the polysaccharide derivative (luster pigment/polysaccharide derivative) is preferably 5/95 or more, more preferably 7/93 or more, even more preferably 9/91 or more, and preferably 50/50 or less, more preferably 40/60 or less, and even more preferably 35/65 or less. When the mass ratio (luster pigment/polysaccharide derivative) is equal to or greater than the lower limit, the silky feel can be further improved. When the mass ratio (luster pigment/polysaccharide derivative) is equal to or less than the upper limit, the water-resistant adhesion can be further improved.

Other additives:
The glossy coating film may contain additives such as curing agents, binder resins, other glossy pigments excluding flaky titanic acid, colorants (pigments, dyes, etc.), extender pigments, anti-rust pigments, UV absorbers, light stabilizers, antioxidants, plasticizers, dispersants, leveling agents, surface conditioners, anti-sagging agents, thickeners, defoamers, lubricants, anti-settling agents, and rheology control agents, as appropriate, provided that the additives do not impair the design.

Examples of the curing agent include polyisocyanate compounds, amino resins, polycarboxylic acid compounds, etc., and preferably at least one selected from polyisocyanate compounds and amino resins. By including a curing agent, the water-resistant adhesion of the glossy coating film can be further improved.

Examples of polyisocyanate compounds include aliphatic polyisocyanates such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, dimer acid diisocyanate, and lysine diisocyanate; biuret type adducts, isocyanurate ring adducts, allophanate type adducts, and uretdione type adducts of these aliphatic polyisocyanates; alicyclic diisocyanates such as isophorone diisocyanate, 4,4'-methylenebis(cyclohexyl isocyanate), and methylcyclohexane-2,4- or -2,6-diisocyanate; biuret type adducts and isocyanurate ring adducts of these alicyclic diisocyanates; xylylene diisocyanate, tetramethylxylylene diisocyanate, tolylene Examples of such compounds include aromatic diisocyanate compounds such as diisocyanates, 4,4'-diphenylmethane diisocyanate (MDI), 1,5-naphthalene diisocyanate, and 1,4-naphthalene diisocyanate; biuret-type adducts and isocyanurate ring adducts of these aromatic diisocyanates; hydrogenated MDI and derivatives of hydrogenated MDI; urethane adducts obtained by reacting a polyisocyanate compound with the hydroxyl groups of a polyol such as ethylene glycol, propylene glycol, 1,4-butylene glycol, dimethylolpropionic acid, polyalkylene glycol, trimethylolpropane, and hexanetriol in a ratio such that there is an excess of isocyanate groups; biuret-type adducts and isocyanurate ring adducts of these urethane adducts.

The polyisocyanate compound may be blocked. A blocked polyisocyanate compound is one in which a blocking agent is added to the isocyanate group of the above polyisocyanate compound. The blocked polyisocyanate compound produced by the addition is stable at room temperature, but it is desirable that the blocking agent dissociates to regenerate free isocyanate groups when heated to the baking temperature of the coating film (usually about 80°C to about 200°C). Examples of blocking agents that satisfy these requirements include phenol-based, lactam-based, alcohol-based, ether-based, oxime-based, active methylene-based, mercaptan-based, acid amide-based, imide-based, amine-based, imidazole-based, and pyrazole-based blocking agents. Among these, blocked polyisocyanate compounds using active methylene-based and pyrazole-based blocking agents are particularly suitable.

When a polyisocyanate compound is used, its content is preferably within the range of 1 to 300 parts by mass per 100 parts by mass of the total solid content of the polysaccharide derivative.

Examples of amino resins include methylolated amino resins obtained by reacting amino components such as melamine, urea, benzoguanamine, acetoguanamine, steroguanamine, spiroguanamine, and dicyandiamide with aldehydes. Examples of aldehydes include formaldehyde, paraformaldehyde, acetaldehyde, and benzaldehyde. In addition, methylolated amino resins etherified with a suitable alcohol can also be used. Examples of alcohols used for etherification include methyl alcohol, ethyl alcohol, n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, i-butyl alcohol, 2-ethylbutanol, and 2-ethylhexanol. Melamine resins are preferred as amino resins, and methylolated melamine resins in which at least a portion of the methylol groups has been alkyl-etherified can be preferably used.

When an amino resin is used, its content is preferably within the range of 1 to 300 parts by mass per 100 parts by mass of the total solid content of the polysaccharide derivative.

Examples of binder resins include acrylic resins and polyester resins, with acrylic resins being preferred.

The acrylic resin may be a homopolymer or copolymer obtained by radical polymerization of a radically polymerizable monomer mainly composed of an acrylic acid ester and/or a methacrylic acid ester. It is preferable that the polymer molecule contains a crosslinkable functional group such as a hydroxy group or a carboxy group.

Examples of acrylic acid esters and methacrylic acid esters include monoesters of acrylic acid or methacrylic acid with monohydric alcohols having 1 to 20 carbon atoms, and specific examples include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate, hexyl acrylate, hexyl methacrylate, lauryl acrylate, and lauryl methacrylate.

Examples of monomers containing the above-mentioned crosslinkable functional groups include hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, caprolactone hydroxyethyl acrylate, caprolactone hydroxyethyl methacrylate, acrylic acid, methacrylic acid, maleic acid, and fumaric acid. In addition to the above, other monomers capable of radical copolymerization with the above-mentioned monomers can be used, such as unsaturated compounds having one or more polymerizable double bonds in one molecule, such as acrylonitrile, methacrylonitrile, styrene, vinyl acetate, vinyl methyl ether, vinyl chloride, vinylidene chloride, ethylene, and propylene.

The acid value of the acrylic resin is preferably within the range of 3 mg KOH/g to 50 mg KOH/g. If the acid value is too low, the adhesion of the coating film may decrease, and conversely, if the acid value is too high, the water resistance may decrease.

The weight-average molecular weight (Mw) of the acrylic resin is preferably within the range of 200,000 to 1,000,000. If the weight-average molecular weight is too low, the effect of the present invention of stably maintaining the orientation of the glittering pigment in the coating film state before curing may not be fully obtained. If the number-average molecular weight is too high, the glittering pigment composition may have poor solubility in a solvent or may have too high a viscosity, resulting in poor handling. The weight-average molecular weight can be determined by gel permeation chromatography (GPC) using styrene polymer as a standard. The ratio of the polysaccharide derivative to the binder resin is preferably within the range of 10/90 to 90/10 by solid mass ratio of polysaccharide derivative/binder resin, from the viewpoint of further improving water-resistant adhesion, weather resistance, etc., more preferably 30/70 to 70/30, and even more preferably 40/60 to 60/40.

Other examples of the luster pigments include scaly particles _such as mica (artificial mica, synthetic mica, etc.), silica, alumina, and glass flakes, and scaly particles having a multilayer film made of a metal oxide such as _TiO2 , _SnO2 , _ZrO2 , _Fe2O3 , _ZnO2 , _Cr2O3 , _{and V2O5} on the surface of the particles; colored aluminum flake pigments; metallic titanium _flake pigments; stainless steel flake pigments; plate-shaped iron oxide pigments; and hologram pigments.

Extender pigments include baryta powder, precipitated barium sulfate, barium carbonate, calcium carbonate, gypsum, clay, silica, white carbon, diatomaceous earth, talc, magnesium carbonate, alumina white, gloss white, mica powder, etc.

Anti-rust pigments include aluminum dihydrogen tripolyphosphate and aluminum phosphomolybdate.

Examples of ultraviolet absorbents include benzotriazole-based absorbents, triazine-based absorbents, salicylic acid derivative-based absorbents, and benzophenone-based absorbents.

[Method for producing glittery coated products]
The method for producing a glittering coated article of the present invention includes the steps of preparing a glittering pigment composition containing a glittering pigment, a polymeric compound having a basic group or a salt thereof, and a solvent, and applying the glittering pigment composition to a substrate to form a glittering coating film.

Specifically, the brightly coated article of the present invention can be produced as follows:

First, a layered titanate is treated with acid or hot water to obtain layered titanic acid, and then a polymeric compound or its salt having a basic group with an interlayer swelling effect is applied to obtain flaky titanic acid in which the interlayers in the layered crystal structure are swollen and peeled off. When applying the polymeric compound or its salt having a basic group, it is applied in an amount of more than 0.1 equivalent and less than 0.5 equivalent to the exchangeable ion capacity of the titanic acid.

Next, by adding flaky titanic acid to the solvent and stirring, a glittering pigment composition in which the flaky titanic acid is dispersed in the solvent can be obtained. When a polysaccharide derivative is used, it is preferable to prepare a solution by adding the polysaccharide derivative to an organic solvent. By adding the above-mentioned flaky titanic acid to the obtained solution and stirring, a glittering pigment composition in which the flaky titanic acid is dispersed in the organic solvent can be obtained.

The solvent may be an organic solvent or water. Therefore, the photoluminescent pigment composition may be a solvent-based paint or a water-based paint.

The organic solvent is not particularly limited, but examples thereof include aromatic hydrocarbons such as xylene, toluene, and ethylbenzene; aliphatic hydrocarbons such as hexane and heptane; esters such as ethyl acetate, n-butyl acetate, and isobutyl acetate; halogenated hydrocarbons such as carbon tetrachloride; alcohols such as methanol, ethanol, isopropanol, n-butanol, sec-butanol, and isobutanol; ethers such as n-butyl ether, dioxane, ethylene glycol monomethyl ether, and ethylene glycol monoethyl ether; and ketones such as methyl ethyl ketone, methyl isobutyl ketone, and diisobutyl ketone. Among these, the organic solvent is preferably an aromatic hydrocarbon or an ester. These organic solvents may be used alone or in combination.

The content of the organic solvent is not particularly limited and can be adjusted as appropriate. For example, taking into consideration the viscosity suitable for application, the content can be 60% by mass or more and 90% by mass or less in 100% by mass of the glittering pigment composition.

Next, the obtained photoluminescent pigment composition is applied to a substrate and dried to obtain the photoluminescent coated article of the present invention. The coating film constituting the photoluminescent coated article usually has a cured film thickness of preferably 1 μm to 200 μm, more preferably 10 μm or more and 150 μm or less, and even more preferably 20 μm or more and 50 μm or less.

During application, it is preferable to set the solids concentration of the glitter pigment composition to 10% by mass or more and 40% by mass or less in order to obtain a more excellent silky feel.

The photoluminescent pigment composition can be applied by, for example, spin coating, spray coating, roller coating, dip coating, flow coating, knife coating, electrostatic coating, bar coating, die coating, brush coating, dripping, etc.

The heating conditions for the method of forming a coating film from the photoluminescent pigment composition are not particularly limited, but can be, for example, performed by holding the mixture at 60°C to 200°C for 5 to 30 minutes.

A topcoat layer may be formed on the obtained glossy coating film by applying a paint such as a clear paint. Examples of clear paint include solvent-based paint, water-based paint, water-dispersed paint, and powder paint. The clear paint may be a colored clear paint. There are no particular limitations on the components contained in the clear paint, and it is possible to use a paint that contains a film-forming thermosetting resin and a hardener.

Preferred examples of solvent-based clear paints, from the standpoint of transparency or acid etching resistance, include a combination of acrylic resin and/or polyester resin with an amino resin, or an acrylic resin and/or polyester resin with a carboxylic acid-epoxy curing system.

An example of a water-based clear paint is one that contains a resin that has been neutralized with a base to make the film-forming resin contained in the examples of the solvent-based clear paints listed above water-based. This neutralization can be carried out by adding a tertiary amine such as dimethylaminoethanol or triethylamine before or after polymerization.

On the other hand, as the powder-type clear paint, ordinary powder paints such as thermoplastic and thermosetting powder paints can be used. Thermosetting powder paints are preferred because they give a coating film with good physical properties. Specific examples of thermosetting powder paints include epoxy-based, acrylic-based, and polyester-based powder clear paints, with acrylic-based powder clear paints being particularly preferred because of their good weather resistance.

The glitter coating of the present invention, formed on the surface of a substrate, exhibits an excellent silky feel, a pale blue (sky blue) color due to scattered light even without the addition of color pigments, and has excellent water-resistant adhesion, so it can be used, for example, for the exterior panels of automobile bodies such as passenger cars, trucks, motorcycles, and buses; automobile parts; and the exterior panels of household electrical appliances such as refrigerators, washing machines, smartphones, and audio equipment, and is particularly suitable for use in the exterior panels of automobile bodies and automobile parts.

The present invention will be described in more detail below based on specific examples. The present invention is not limited to the following examples, and can be modified as appropriate within the scope of the gist of the invention.

<Synthesis of flaky titanic acid>
(Synthesis Examples 1 to 4)
The raw material obtained by dry grinding and mixing 67.01 g of titanium oxide, 26.78 g of potassium carbonate, 12.04 g of potassium chloride, and 5.08 g of lithium hydroxide was calcined at 1020 ° C for 4 hours. 7.9 kg of 10.9% water slurry of the obtained powder was prepared, and 470 g of 10% sulfuric acid aqueous solution was added and stirred for 2 hours, and the pH of the slurry was adjusted to 7.0. The separated and washed product was dried at 110 ° C, and then calcined at 600 ° C for 12 hours. The obtained white powder was titanate K _0.6 Li _0.27 Ti _1.73 O _3.9 with a layered crystal structure, and had an average major axis of 15 μm.

32.5 g of this titanate having a layered crystal structure was dispersed in 474.8 g of deionized water, and while stirring, 25.2 g of 95% sulfuric acid was added, and the mixture was reacted at room temperature for 1 hour, after which it was separated by suction filtration and washed with water. The same process was carried out again with the obtained solid matter. The remaining amount of K ₂ O in the obtained layered titanic acid was 2.0%, and the metal ion exchange rate was 94%.

The total amount of the obtained layered titanic acid was added to deionized water so that the total weight was 2.5 kg. While dispersing and stirring, both-end amino-modified silicone (manufactured by Shin-Etsu Silicone Co., Ltd.) was added in the amount shown in Table 1 below, and the mixture was stirred at room temperature for 1 hour. The mixture was then separated by suction filtration and washed with water to obtain flaky titanic acid.

The amino-modified silicones A to B shown in Table 1 are as follows:

Amino-modified silicone A: Amino-modified silicone with both ends (Shin-Etsu Silicone Co., Ltd., X-22-161A, side chain: methyl group, kinetic viscosity at 25° C.: 25 mm ² /s, functional group equivalent: 800 g/mol)
Amino-modified silicone B: Amino-modified silicone with both ends (Shin-Etsu Silicone Co., Ltd., X-22-161B, side chain: methyl group, kinetic viscosity at 25° C.: 55 mm ² /s, functional group equivalent: 1500 g/mol)

(Synthesis Example 5)
The total amount of layered titanic acid obtained in the same manner as in Synthesis Examples 1 to 4 was added to deionized water so that the total weight of the mixture with the deionized water was 800 g. While dispersing and stirring, a solution of 17.3 g of dimethylethanolamine (1 equivalent relative to the layered titanic acid) in 182.8 g of deionized water was added, and the mixture was stirred at room temperature for 12 hours to obtain flaky titanic acid.

<Preparation of Glittering Pigment Composition and Glittering Coating Film>
Example 1
The flaky titanic acid obtained in Synthesis Example 2 was mixed with a 10% by mass solution (solvent: xylene) of ethyl cellulose (hydroxyl group substitution degree: 2.54, organic group: ethyl group) using a defoaming conditioning mixer "Awatori Rentaro AR-250" (manufactured by Thinky Corporation) for 10 minutes (rotation: 800 rpm, revolution: 2000 rpm) so that the PWC (pigment concentration) was 10% by mass, and then defoamed for 2 minutes (rotation: 60 rpm, revolution: 2200 rpm) to obtain a glittering pigment composition (flaky titanic acid-containing coating composition). The glittering pigment composition obtained did not show any sedimentation of solids even when left to stand for a long period of time, and had sufficient dispersion stability.

Next, the above-mentioned glittering pigment composition was applied twice to a hiding rate test paper (black undercoat) using a film applicator with a clearance of 200 μm. In this process, a glittering coating film was formed by drying at room temperature after each application, and a glittering coating was obtained. The thickness of the resulting glittering coating film was 30 μm. It was also confirmed that the resulting glittering coating film had flaky titanic acid with an average thickness of 40 nm and an average major axis of 15 μm, which was uniformly and parallelly dispersed and oriented in a very dense state in the resin coating film. In the examples and comparative examples, the average major axis and average thickness of the flaky titanic acid were measured by observing the cross section of the coating film with a SEM (scanning electron microscope). As the SEM, Hitachi's product number "S-4000" was used. The average major axis was the average particle diameter of 100 flaky titanic acid particles measured, and the average thickness was the average thickness of 100 flaky titanic acid particles measured.

Example 2
A glittering pigment composition and a glittering coating film were prepared in the same manner as in Example 1, except that the flaky titanic acid obtained in Synthesis Example 2 was used so that the PWC was 20 mass %, and a glittering coating product was obtained. The thickness of the resulting glittering coating film was 32 μm.

Example 3
A glittering pigment composition and a glittering coating film were prepared in the same manner as in Example 1, except that the flaky titanic acid obtained in Synthesis Example 2 was used so that the PWC was 30 mass %, and a glittering coated product was obtained. The thickness of the resulting glittering coating film was 34 μm.

Example 4
A glittering pigment composition and a glittering coating film were prepared in the same manner as in Example 1, except that the flaky titanic acid obtained in Synthesis Example 4 was used so that the PWC was 10 mass %, and a glittering coated product was obtained. The thickness of the resulting glittering coating film was 29 μm.

(Comparative Example 1)
A pigment composition and a coating film were prepared in the same manner as in Example 1, except that the flaky titanic acid obtained in Synthesis Example 1 was used so that the PWC was 10 mass %, and a coated article was obtained. The coating film obtained had a thickness of 28 μm.

(Comparative Example 2)
Except for using the flaky titanic acid obtained in Synthesis Example 3 so that the PWC was 10 mass %, a pigment composition and a coating film were prepared in the same manner as in Example 1, and a coated article was obtained. The thickness of the resulting coating film was 31 μm.

(Comparative Example 3)
Except for using the flaky titanic acid obtained in Synthesis Example 5 so that the PWC was 10 mass %, and mixing with a water-based urethane paint (urethane resin) instead of ethyl cellulose (hydroxyl group substitution degree: 2.54, organic group: ethyl group), a pigment composition and a coating film were prepared in the same manner as in Example 1, and a coated article was obtained. The coating film obtained had a thickness of 26 μm.

(Comparative Example 4)
Except for using a white background as the hiding power test paper, a pigment composition and a coating film were prepared and a coated product was obtained in the same manner as in Comparative Example 3. The thickness of the obtained coating film was 26 μm.

(Comparative Example 5)
A pigment composition and a coating film were prepared in the same manner as in Example 1, except that a conventional pearl pigment, titanium oxide-coated flaky alumina (product name "Xiralic T50-10", manufactured by Merck), was used in place of flaky titanic acid so as to give a PWC of 10 mass %, and a coated article was obtained. The coating film obtained had a thickness of 35 μm.

(Comparative Example 6)
Except for using a white background as the hiding power test paper, a pigment composition and a coating film were prepared and a coated product was obtained in the same manner as in Comparative Example 5. The coating film obtained had a thickness of 35 μm.

<Evaluation of coating film>
The design properties (grainy feel, silky feel, color measurement) of the coatings obtained in Examples 1 to 4 and Comparative Examples 1 to 6 were evaluated by the following test methods. In addition, the pigment compositions in Examples 1 to 4 and Comparative Examples 1 to 4 were applied to white painted panels in the same manner as in Example 1 to obtain glitter coatings, and the water-resistant adhesion was evaluated by the following test method.

[Grainy feel]
The graininess of the coating film was visually evaluated according to the following criteria.

◯: No graininess ×: Graininess

[Silky feel]
The lightness (L* value) of the obtained coating film (black background part of the hiding rate test paper) was measured at an incident angle of 45° and light receiving angles of 15°, 25°, 45°, 75°, and 110° using a multi-angle spectrophotometer ( ^MA68II , manufactured by X-Rite Corporation), and the flop index value (FI value) calculated from the measured lightness was used for evaluation. Note that a higher FI value indicates a more excellent silky feel.

[Color Measurement]
The chroma c ^* value and hue angle h value of the obtained coating film were measured at light receiving angles of 15°, 25°, 45°, 75°, and 110° with respect to an incident angle of 45° using a multi-angle spectrophotometer (MA68II, manufactured by X-Rite Corporation). Note that the larger the chroma c ^* value, the more vivid the color, and a hue angle h=270° indicates a bluer color. The c ^* value and h value (°) in Table 2 below indicate the average values at light receiving angles of 15°, 25°, 45°, 75°, and 110°.

[Water-resistant adhesion (cross-cut test)]
According to "JIS K5400 General Test Methods for Paints," the glitter coating was immersed in 40°C warm water for 5 hours, and then a cross-cut (2 mm square, 100 grids) tape peel test was performed to evaluate water-resistant adhesion.

<Evaluation results of coating film>
The results are shown in Table 2 below.

As is clear from the evaluation results of the coating film, Examples 1 to 4 have no particle feel at all compared to Comparative Example 5 and Comparative Example 6, and Example 4 has a superior silky feel and has excellent design properties. In addition, in Examples 1 to 4, in which a glittering pigment composition containing flaky titanic acid with an average thickness of 20 nm or more and 60 nm or less was applied, the c ^* value was high and the h value was close to 270°, indicating that a blue color was developed. On the other hand, in Comparative Examples 1 and 2, in which a pigment composition containing flaky titanic acid with an average thickness outside the range of 20 nm or more and 60 nm or less was applied, the c ^* value was low, indicating that the blue color was not developed sufficiently. This shows that by applying a glittering pigment composition containing flaky titanic acid with an average thickness of 20 nm or more and 60 nm or less to the surface of a substrate, a glittering coating film that is completely free of particle feel and has an excellent silky feel and shows a pale blue (sky blue) color due to scattered light can be obtained. In addition, it can be seen that Examples 1 to 4, which used a polymer compound having a basic group or a salt thereof, had superior water-resistant adhesion compared to Comparative Examples 3 and 4, which used a low molecular weight amine.

Reference Signs List 1... Glossy coating 2... Substrate 2a, 2b... Surface 3... Glossy coating film 11... Layered titanate 12... Hydrophobic amine 13... Flake-like titanic acid 14... Polysaccharide derivative

Claims (11)

A glittering coated article comprising a substrate and a glittering coating film provided on a surface of the substrate,
The glittering coating film contains a glittering pigment, a polymer compound having a basic group or a salt thereof , and a polysaccharide derivative ,
The bright pigment is a flaky titanic acid having an average thickness of 20 nm or more and 60 nm or less,
The polysaccharide derivative is formed by substituting at least a portion of the hydrogen atoms in hydroxyl groups contained in the polysaccharide with organic groups . The glittering coated article according to claim 1 , wherein the L ^* value of the substrate surface in the L ^* c ^* h color system is less than 40. The lustrous coated article according to claim 1 or 2, wherein the flaky titanic acid is formed by allowing a polymeric compound or a salt thereof having a basic group in an amount of more than 0.1 equivalent and less than 0.5 equivalent relative to the exchangeable ion capacity of the titanic acid to act on the titanic acid having a layered crystal structure, thereby swelling and peeling the interlayers in the layered crystal structure. The shiny coating according to any one of claims 1 to 3, wherein the polymer compound having a basic group or a salt thereof is an amino-modified silicone. The glittering coating according to any one of claims 1 to 4, wherein the average long diameter of the flaky titanic acid is 5 μm or more and 30 μm or less. The glittering coating according to any one of claims 1 to 5, wherein the glittering pigment content in the glittering coating is 1% by mass or more and 40% by mass or less in terms of pigment concentration (PWC). The glittering coating according to any one of claims 1 to 6, wherein the organic group is at least one selected from the group consisting of an alkyl group having a substituent, an alkyl group having no substituent, an acyl group having a substituent, and an acyl group having no substituent. The glittering coating according to any one of claims 1 to 7, wherein the polysaccharide is cellulose. The glittering coating according to any one of claims 1 to 8 , wherein a mass ratio of the glittering pigment to the polysaccharide derivative (glittering pigment/polysaccharide derivative) is 5/95 or more and 50/50 or less. The glittering coating according to any one of claims 1 to 9 , wherein the glittering coating has a thickness of 10 μm or more and 150 μm or less. A method for producing a glittering coated article according to any one of claims 1 to 10 ,
A step of preparing a bright pigment composition containing a bright pigment, a polymer compound having a basic group or a salt thereof, a polysaccharide derivative, and a solvent;
and applying the above-mentioned glittering pigment composition to a substrate to form a glittering coating film.

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