JP6038738B2 - Bright paint composition, bright paint film and laminated paint film - Google Patents

Description

  The present invention relates to a glitter coating composition, a glitter coating film, and a laminated coating film.

  Conventionally, a luster pigment in which a titanium oxide layer is provided on the surface of a scaly material such as natural mica, synthetic mica, or scaly alumina has been used in many fields. These glitter pigments have a strong glitter feeling and have a grain feeling (shiny gloss feeling), and are used as pigments imparting pearl luster. On the other hand, titanic acid flakes (titania nanosheets) and / or used to obtain a glittering pigment that has no particle feeling, has a silky shine, a so-called silky feeling, and can be given a high-quality design. Attempts have been made to improve the resin.

  On the other hand, glitter pigments containing titanic acid flakes tend to peel off locally (so-called chipping occurs) when a coating film, particularly a laminated coating film, is formed as a vehicle exterior. There was a problem. Since titanic acid flakes have high hydrophilicity, they generally have low interaction with hydrophobic resins. Therefore, the adhesiveness of the titanic acid flakes to the resin is low, and the adhesion as a coating film cannot be obtained. In fact, it has been found that chipping occurs between titania layers where there is no resin layer.

  Patent Document 1 relates to a multilayer coating film having higher chipping resistance. Patent Document 1 describes that a base paint containing a scaly titanate pigment is used for forming a base coating film. As the scaly titanate pigment, a layered titanate is treated with an acid. A titanic acid flake is described in which a layered titanic acid is formed, and then an organic basic compound is allowed to act to separate the layers. According to Patent Document 1, such a scaly titanate pigment has a very thin scaly shape, and therefore is present in a more highly oriented orientation in the base coating film, and is locally applied to the multilayer coating film from the outside. Even if a general impact is applied, this impact energy is consumed by the fine destruction of the scaly titanate pigment that is highly oriented as a very large number of pigments, and as a result, It is said that most impact energy can be absorbed in the coating film containing the scaly titanate pigment, thereby improving the chipping resistance of the multilayer coating film.

  Patent Document 2 describes a glittering paint composition containing an amino group-containing acrylic resin having a specific amine value and titanic acid flakes dispersed in the resin. According to Patent Document 2, when an amino group-containing acrylic resin having a specific amine value is used as a resin to form a resin film, the titanic acid flake layers are reinforced, and the titanic acid flakes are contained in the acrylic resin. It is said that a good silky feeling is maintained due to being uniformly dispersed in the film, and as a result, a coating film having excellent silky feeling and adhesion is obtained.

  However, the conventional coating compositions as described above do not have sufficient bonding strength between the titania layers, and can form a coating film with excellent adhesion (particularly initial adhesion and water-resistant adhesion) and excellent design. There is still a need for the development of new coating compositions.

JP 2006-305515 A JP 2012-241072 A

  The present invention provides a glittering paint composition that has a high glitter and exhibits a good silky feeling, and is capable of forming a glittering coating film excellent in initial adhesion and water-resistant adhesion by sufficiently suppressing the occurrence of peeling. The issue is to provide goods.

The present invention includes the following inventions.
(1) A glittering paint composition comprising a titanic acid flake to which a urethane resin is bonded and an acrylic resin.
(2) The titanic acid flakes to which the urethane resin is bonded have the following steps:
(A) mixing a layered titanate with an acid to obtain a hydrogen-type layered titanic acid;
(B) mixing a hydrogen-type layered titanic acid with a basic substance to obtain a single-layer titanate flake, and (c) mixing the single-layer titanate flake with a urethane resin having an anionic hydrophilic group, The glittering paint composition according to (1) above, which is obtained by a method including a step of heating the obtained mixture.
(3) The glittering paint composition according to (2), wherein heating is performed at 35 to 60 ° C. for 5 minutes or longer in the step (c).
(4) The glittering paint composition according to the above (2), wherein heating is performed at 65 to 90 ° C. for 8 minutes or less in the step (c).
(5) A glittering coating film comprising a titanic acid flake to which a urethane resin is bonded and an acrylic resin, wherein the titanic acid flake to which the urethane resin is bonded is dispersed in the acrylic resin. Coating film.
(6) A laminated coating film comprising at least a base layer and a clear layer laminated on a substrate, wherein the glittering coating film according to (5) is disposed between the base layer and the clear layer The above laminated coating film.

  According to the glittering paint composition of the present invention, a glittering resin coating film having high glitter and excellent silky feeling, sufficiently suppressed in occurrence of peeling and excellent in initial adhesion and water-resistant adhesion. It becomes possible to do.

FIG. 1 is a diagram showing a reaction mechanism of a urethane resin having an anionic hydrophilic group and a single layer of titanic acid flakes in the production of the glittering paint composition of the present invention.

  The glittering paint composition of the present invention comprises a titanic acid flake to which a urethane resin is bonded and an acrylic resin. Since the titanic acid flakes to which the urethane resin is bonded have reinforced bonding between the titania layers, high adhesion can be imparted to the resulting coating film. In addition, since the urethane resin has a urethane bond having a strong cohesive force, the obtained coating film has excellent adhesion to the substrate. Further, the refractive index of the titanic acid flakes is higher than that of the acrylic resin, and the presence of both components having different refractive indexes in the coating film results in a silky feeling with no particle feeling. Therefore, the coating film obtained using the glittering paint composition of the present invention has high glitter and a good silky feeling, and the occurrence of peeling is sufficiently suppressed, and the initial adhesion and water-resistant adhesion are excellent.

The titanate flakes to which the urethane resin is bonded are as follows:
(A) mixing a layered titanate with an acid to obtain a hydrogen-type layered titanic acid;
(B) mixing a hydrogen-type layered titanic acid with a basic substance to obtain a single-layer titanate flake, and (c) mixing the single-layer titanate flake with a urethane resin having an anionic hydrophilic group, It can be obtained by a method including a step of heating the obtained mixture.

  Examples of the step (a) include a method described in JP-A No. 2000-344520, and examples of the step (b) include Chem. , Master. The method described in 2003, 15, 3564-3568 is mentioned.

Examples of the layered titanate used in the step (a) include a lepidocrotite type layered titanate (for example, Cs _x Ti _{2-x / 4} O ₄ (where 0.5 ≦ x ≦ 1), A _x Ti _{2-x / 3} Li _{x / 3} O ₄ (where A = K, Rb, Cs; 0.5 ≦ x ≦ 1) and the like. Specific examples of the lipid docrosite type layered titanate include K _0.8 Ti _1.73 Li _0.27 O ₄ , Rb _0.75 Ti _1.75 Li _0.25 O ₄ , Cs _0.7 Ti _1.77 Li _0.23 O ₄ , Cs _0.7 Ti _1.825 O _{4 and the} like.

The above-mentioned lepidocrotite-type layered titanate includes, for example, K ₂ CO ₃ , Rb ₂ CO ₃ , or Cs ₂ CO ₃ , anatase-type TiO _2, and other metals such as Li ₂ CO _{3 as} necessary. It can be prepared by mixing carbonate with a predetermined molar ratio and calcining the mixture at a high temperature of 600 to 1200 ° C. for 6 to 24 hours in the air.

  When the aspect ratio of the obtained titanate flakes is to be increased, a large layered titanate is prepared using a molten salt such as KCl when preparing the layered titanate, which will be described later. A method of sequentially performing acid treatment and base treatment is effective.

  The thus prepared lipidocrosite-type layered titanate is composed of a host layer, a metal ion layer, and an octahedron in which six oxygen atoms are coordinated to titanium and linked in a two-dimensional direction. Have a crystal structure in which are alternately stacked. The host layer is negatively charged as a whole layer because part of the titanium site is vacant. The negative charge is compensated by the metal ion layer, so that the entire lepidocrocite-type layered titanate is electrically neutral.

In step (a), the layered titanate is mixed with an acid and stirred. Since the metal ion layer exhibits high ion exchange properties, while maintaining the layered structure by this acid treatment, metal ions other than Ti are exchanged at high levels, preferably all with hydrogen ions, and hydrogen-type layered titanic acid (for example, _{, H x Ti 2-x /} 4 O 4 · nH 2 O ( provided _{that, 0.5 ≦ x ≦ 1),} H x + x / 3 Ti 2-x / 3 O 4 · nH 2 O ( provided that, 0.5 ≦ x ≦ 1)) is formed. Thereafter, the obtained hydrogen-type layered titanic acid is washed. In order to exchange metal ions other than Ti with hydrogen ions at a higher level, it is preferable to repeat the acid treatment and the washing treatment a plurality of times.

  The treatment time with the acid is preferably about 1 to 5 days. Even if the treatment time with the acid is shorter than the above lower limit or longer than the above upper limit, even if the base treatment described later is applied, the layered titanic acid tends to be hardly peeled to a single layer.

  Examples of the acid include strong acids such as hydrochloric acid, nitric acid and sulfuric acid. The acid concentration is preferably 0.1 to 10N. The layered titanate is preferably mixed in an amount of 1 to 50 g with respect to 1 L of the acid having the above concentration. The acid treatment temperature is preferably 0 to 50 ° C. By setting these conditions within the above range, the metal ions tend to be exchanged with hydrogen ions at a higher level in the acid treatment time.

  Next, in step (b), hydrogen-type layered titanic acid is mixed with a basic substance and stirred. Hydrogen-type layered titanic acid is a kind of solid acid, and when mixed with a basic substance, the basic substance is taken in between the layers as a guest. At this time, when the mixture is vigorously stirred, the layered titanic acid is separated into a single layer (nanosheet), and a dispersion containing a single layer of titanic acid flakes is obtained.

  The base treatment time is preferably about 1 to 5 days. When the time of the base treatment is shorter than the above lower limit, the layered titanic acid tends to be hardly peeled up to a single layer. On the other hand, if it is longer than the above upper limit, the titanate flakes are destroyed and the aspect ratio tends to be small.

  Examples of the basic substance include dimethylethanolamine (DMEA), tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide ( Ammonium salts such as TBAH), tetrabutylammonium chloride (TBAC), tetraoctylammonium chloride (TOAC), tetradodecylammonium chloride (TDAC), tetrastearylammonium chloride (TSAC), and the like. From the standpoint of hydrophobic balance, dimethylethanolamine (DMEA), tetraethylammonium hydroxide (TEAH), and tetrapropylammonium hydroxide (TPAH) should be used. Preferably, it is particularly preferable to use TEAH and TPAH. The basic substance is usually used after being dissolved in a solvent such as water. The concentration of the basic substance in this solution is preferably 0.1 to 3 mol / L. The hydrogen-type layered titanic acid needs to be mixed so that the molar ratio to the basic substance (layered titanic acid / basic substance) is 1/5 to 2/1. The molar ratio is about 2 It is particularly preferable to mix so as to be / 1. The temperature for the base treatment is preferably 0 to 50 ° C. By setting these conditions within the above range, it tends to be able to form a nanosheet at a higher level in the base treatment time.

  Since the single layer titanate flakes obtained in the step (b) have a thickness on the order of nm and a high aspect ratio, the titanate flakes are finely dispersed in the coating film and oriented with respect to the coating film surface. And the coating film which does not have a particle feeling at all by the multiple reflection of the light by a titanic acid flake, and exhibits a pearl tone (silky feeling) can be obtained.

  The titanate flakes used in step (c) preferably have an average thickness of 0.5 to 300 nm, more preferably 0.5 to 100 nm. Those having an average thickness less than the above lower limit generally tend to be difficult to produce. On the other hand, if an average thickness exceeding the upper limit is used, the particle feeling is conspicuous and the silky feeling tends to be impaired. .

  The titanic acid flakes used in step (c) are preferably those having an average major axis of 5 to 50 μm, more preferably 15 to 50 μm. If the average major axis is less than the above lower limit, sufficient silky feeling tends to be difficult to obtain, while those having an average major axis exceeding the upper limit tend to be difficult to produce in general. Here, the average major axis means the average grain size in the plane direction perpendicular to the thickness direction of the titanate flakes. Moreover, such an average major axis and the above-mentioned average thickness can be measured by observation with a scanning electron microscope (SEM) or the like.

  Furthermore, it is preferable that the average aspect-ratio (ratio of the average major axis with respect to average thickness) of the titanic acid flake used in a process (c) is 1000-10000. If the average aspect ratio is less than the above lower limit, a sufficient silky feeling tends to be difficult to obtain. On the other hand, if it exceeds the upper limit, it tends to be difficult to uniformly disperse the titanic acid flakes in the resin film.

  An amine added to neutralize the anionic hydrophilic group of the urethane resin by the heat treatment in the step (c), and a basic substance (for example, an ammonium salt) incorporated as a guest between the layers of the titanic acid flakes; Thus, a titanic acid flake in which the guest and the urethane resin are bonded is obtained (see FIG. 1).

  As the urethane resin having an anionic hydrophilic group used in the step (c), it is preferable to use, for example, a urethane resin having a carboxylic acid group introduced therein. Although it does not specifically limit as a urethane resin, Resin which has a urethane bond obtained by reaction of the following polyol component and a polyisocyanate compound is mentioned. Examples of the polyisocyanate compound include 2,4-tolylene diisocyanate (2,4-TDI), 2,6-tolylene diisocyanate (2,6-TDI), and mixtures thereof (TDI), diphenylmethane-4,4 ′. Diisocyanate (4,4′-MDI), diphenylmethane-2,4′-diisocyanate (2,4′-MDI), and mixtures thereof (MDI), dicyclohexylmethane diisocyanate (hydrogenated MDI), naphthalene-1,5- Diisocyanate (NDI), 3,3′-dimethyl-4,4′-biphenylene diisocyanate, xylylene diisocyanate (XDI), dicyclohexylmethane diisocyanate (hydrogenated HDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI) Hydrogenated xylylene diisocyanate (HXDI), and the like, dicyclohexylmethane diisocyanate (hydrogenated MDI), isophorone diisocyanate (IPDI) and hexamethylene diisocyanate (HDI) is preferable. Examples of the polyol component include acrylic, polyester, polyether, polycarbonate, and the like, and polyether and polycarbonate are preferable from the viewpoint of hydrolysis resistance. Moreover, as a urethane resin which has an anionic hydrophilic group used for the glittering paint composition of this invention, a non-yellowing type urethane resin is preferable.

  The heat treatment step of the step (c) is preferably performed at 35 to 60 ° C. for 5 minutes or more from the viewpoint of reacting the urethane resin having an anionic hydrophilic group and the titanic acid flakes (step (c1)). The heat treatment step is particularly preferably performed at 38 to 50 ° C, more preferably 40 to 45 ° C. The heat treatment step is preferably performed for 5 to 100 minutes, particularly preferably 8 to 80 minutes, and more preferably 8 to 70 minutes.

  Alternatively, the heat treatment step of the step (c) is preferably performed at 65 to 90 ° C. for 8 minutes or less from the viewpoint of preventing the paste viscosity from increasing and difficult to disperse the titanate flakes (step (c2)). ). The heat treatment step is particularly preferably performed at 70 to 95 ° C, more preferably 75 to 90 ° C. The heat treatment step is preferably performed for 2 to 8 minutes, particularly preferably 2 to 6 minutes.

  In the step (c), the hydrophilic group introduced into the urethane resin also serves as a functional group for cross-linking, so that the cross-linking reaction proceeds by heat treatment, and the bond between the titania layers is further reinforced, thereby improving the adhesion. It is considered effective.

  The titanic acid flakes to which the urethane resin obtained in step (c) is bonded preferably have an average thickness of 0.5 to 300 nm, an average major axis of 5 to 50 μm, and an average aspect ratio. Those having a ratio of 1000 to 10,000 are preferred.

  The glittering paint composition of the present invention contains an acrylic resin. The acrylic resin is not particularly limited, and examples thereof include a copolymer of an acrylic monomer and another ethylenically unsaturated monomer. Examples of the acrylic monomer that can be used in the copolymer include methyl, ethyl, propyl, n-butyl, i-butyl, t-butyl, 2-ethylhexyl, lauryl, phenyl, benzyl, and acrylic acid or methacrylic acid. Esterified compounds such as 2-hydroxyethyl, 2-hydroxypropyl, 4-hydroxybutyl, ring-opening adducts of caprolactone of acrylic acid or 2-hydroxyethyl methacrylate, glycidyl acrylate, glycidyl methacrylate, acrylamide, methacrylamide And N-methylol acrylamide, (meth) acrylic acid esters of polyhydric alcohol, acrylic acid esters and methacrylic acid esters. Examples of the other ethylenically unsaturated monomers copolymerizable with these include, for example, acrylonitrile, styrene and styrene derivatives, acrylic acid, methyl acrylate, ethyl acrylate, propyl acrylate, hydroxyethyl acrylate, methacrylic acid, methyl methacrylate, and ethyl methacrylate. , Vinyl monomers such as propyl methacrylate and hydroxyethyl methacrylate.

  It is preferable that content of the said urethane resin is 5-50 mass% with respect to the total amount of the urethane resin and acrylic resin in the glittering coating composition of this invention, and it is 10-20 mass%. Particularly preferred.

  The total amount of the urethane resin and the acrylic resin is preferably 5 to 20% by mass and particularly preferably 12 to 17% by mass with respect to the glittering coating composition of the present invention.

  The content of the titanic acid flakes to which the urethane resin is bonded is obtained from the viewpoint of obtaining a coating film having excellent adhesion while obtaining a sufficient silky feeling, and the urethane resin in the glittering paint composition of the present invention and It is preferable that it is 10 mass% or more with respect to the total amount of an acrylic resin, and it is especially preferable that it is 10-30 mass%.

  The glittering paint composition of the present invention can appropriately contain other additives as long as the effects of the present invention are not hindered. Examples of other additives include general paint additives such as thickeners, ultraviolet absorbers, antioxidants, leveling agents, surface preparation agents, anti-sagging agents, antifoaming agents, and active agents. The total amount of the other additives is usually 5% by mass or less, preferably 1% by mass or less, based on the composition. Moreover, it is 10 mass% or less normally with respect to a coating film, Preferably it is 3 mass% or less.

  The glittering paint composition of the present invention can be obtained by dispersing titanic acid flakes bonded with a urethane resin in an acrylic resin solution. Examples of the dispersion method include a method using a stirrer, an ultrasonic disperser, a three roll mill, and the like.

  The present invention also relates to a glitter coating film. The glitter coating film of the present invention contains a titanic acid flake to which a urethane resin is bonded and an acrylic resin, and the titanic acid flake to which the urethane resin is bonded is an acrylic film. Dispersed in the resin. The glitter coating composition of the present invention is suitable for forming the glitter coating film of the present invention.

  The glittering coating film of the present invention can be formed, for example, by coating on a substrate and drying (preheating) and baking (baking and curing) the coating film. The film thickness (film thickness after baking) of the glitter coating film is not particularly limited, but is preferably 5 to 100 μm, and more preferably 10 to 40 μm. When the film thickness is less than the above lower limit, the amount of titanate flakes is small, and it tends to be difficult to obtain a silky feeling. On the other hand, when the film thickness exceeds the above upper limit, a coating film defect such as aside occurs, and the appearance tends to deteriorate.

  The method for applying the glitter coating composition is not particularly limited and includes various conventionally known coating methods, but a coating method that applies a shearing force such as spray coating or doctor blade coating is preferable. Thereby, the titanic acid flakes can be more reliably oriented and dispersed in parallel to the film surface, and there is a tendency to obtain a glittering coating film having a more silky design.

  The base material on which the glittering paint composition is applied is not particularly limited, for example, metals such as iron, aluminum, copper or alloys thereof; inorganic materials such as glass, cement, concrete; polyethylene resin, polypropylene resin , Ethylene-vinyl acetate copolymer resin, polyamide resin, acrylic resin, vinylidene chloride resin, polycarbonate resin, polyurethane resin, epoxy resin and other plastic materials such as various FRPs; fiber materials such as wood, paper and cloth And natural or synthetic materials. The substrate to be coated may be transparent. Preferable substrates to be coated include metals such as iron, aluminum, copper or alloys thereof.

  The present invention also relates to a multilayer coating film, the multilayer coating film of the present invention is a multilayer coating film comprising at least a base layer and a clear layer laminated on a substrate, and is provided between the base layer and the clear layer. The glitter coating film of the present invention is arranged. When forming the laminated coating film of the present invention as a vehicle exterior, the glitter coating film of the present invention is laminated on at least the electrodeposition layer, the intermediate coating layer and the base layer on a substrate such as a steel plate, It is preferable that at least a clear layer is laminated thereon.

  The laminated coating film of the present invention is, for example, laminated on the laminated coating film of the above-mentioned glitter coating composition of electrodeposition coating, intermediate coating, colored base coating by rotary atomization coating, doctor blade coating or spray coating, Furthermore, after laminating a clear paint on this, it can be obtained by baking and curing under conditions suitable for the paint composition.

  Such an electrodeposition layer (electrodeposition coating film) is not particularly limited, and can be obtained, for example, by applying a cationic electrodeposition coating as a primer coating on the surface of a substrate such as a steel plate. Here, as the cationic electrodeposition coating, a known one is preferably obtained by blending an aqueous salt solution or aqueous dispersion of a cationic polymer compound with a crosslinking agent, a pigment or various additives as necessary. Can be used. Examples of the cationic polymer compound include those in which a cationic group such as an amino group is introduced into an acrylic resin or epoxy resin having a crosslinkable functional group, which is neutralized with an organic acid or an inorganic acid. Can be water-soluble or water-dispersed. As a crosslinking agent for curing these polymer compounds, a block polyisocyanate compound, an alicyclic epoxy resin, or the like can be used. The thickness of the electrodeposition layer (thickness after baking) is not particularly limited, but is usually preferably about 10 to 40 μm.

  Further, the intermediate coating composition for forming the intermediate coating layer (intermediate coating film) is not particularly limited. For example, basically, a thermosetting resin composition composed of a base resin and a crosslinking agent is preferably used. Examples of such a base resin include acrylic resins, polyester resins, alkyd resins, etc. having two or more crosslinkable functional groups such as hydroxyl group, epoxy group, isocyanate group, carboxyl group in one molecule. Examples of the agent include amino resins such as melamine resins and urea resins, polyisocyanate compounds which may be blocked, carboxyl group-containing compounds, and the like. The film thickness of the intermediate coating layer (film thickness after baking) is not particularly limited, but is usually preferably about 10 to 30 μm.

  Furthermore, the base paint for forming the base layer (base coating film) is not particularly limited, and for example, a known solvent-based colored base paint or aqueous colored base paint is preferably used. Examples of such an aqueous colored base coating material include a pigment, a resin that can be dissolved or dispersed in water, a crosslinking agent as necessary, and water as a solvent. Examples of the resin that can be dissolved or dispersed in water include a resin containing a hydrophilic group such as a carboxyl group and a crosslinkable functional group such as a hydroxyl group in one molecule, and specifically, an acrylic resin or a polyester resin. And polyurethane resin. Moreover, as a crosslinking agent, hydrophobic or hydrophilic alkyl ether melamine resin, a block isocyanate compound, etc. are mentioned, for example. On the other hand, examples of the solvent-based coloring base paint include those containing a pigment, a resin similar to the above, and a crosslinking agent and a solvent as necessary. The thickness of the base layer (the thickness after baking) is not particularly limited, but is usually preferably about 5 to 20 μm.

  In addition, the clear paint for forming the clear layer (clear coating film) is not particularly limited, and includes, for example, a thermosetting resin and an organic solvent that can form a transparent coating film, and an ultraviolet absorber if necessary. What is being done is mentioned. Examples of the thermosetting resin include acrylic resins having a crosslinkable functional group such as a hydroxyl group, a carboxyl group, a silanol group, and an epoxy group, polyester resins, alkyd resins, fluororesins, urethane resins, and silicon-containing resins. Melamine resin, urea resin, (block) polyisocyanate compound, epoxy resin compound or resin, carboxyl group-containing compound or resin, acid anhydride, alkoxysilane group-containing compound or resin, etc. that can react with these crosslinkable functional groups What consists of a crosslinking agent is mentioned. The film thickness of the clear layer (film thickness after baking) is not particularly limited, but is usually preferably about 20 to 50 μm.

  In the laminated coating film of the present invention, the glittering coating film of the present invention is disposed between the base layer and the clear layer. The method for forming such a glittering coating film is as described above. Moreover, in this invention, the conditions in particular of drying (preheating) and baking (baking hardening) processing of a coating film are not restrict | limited, For example, as drying processing conditions, it is baking processing at 60-90 degreeC for about 1 to 5 minutes. As conditions, 140 to 220 degreeC and about 10 to 40 minutes are employ | adopted suitably.

  The glitter coating film and laminated coating film of the present invention obtained by using the glitter coating composition of the present invention described above exhibit a so-called silky feeling in which the titanate flakes dispersed in the film shine like silk. The silky feeling can be evaluated by flip-flop properties (FF properties) described in Examples described later. In addition, the glittering coating film and the laminated coating film of the present invention are excellent in adhesion because occurrence of peeling is sufficiently suppressed, and the adhesion is determined by a cross-cut peel test described in the examples described later. It is possible to evaluate.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to this.

[Example 1]
1. Production of titanic acid flakes bonded with urethane resin Layered titanic acid was prepared by a known method described in JP-A No. 2000-344520. And Chem. , Master. Using a known method described in 2003, 15, 3564-3568, a single layer of the titania layer was peeled from the obtained layered titanic acid to produce a single-layer titanate flake. The single layer titanate flakes were used to produce titanate flakes bonded with urethane resin.

(Preparation of layered titanic acid)
K ₂ CO ₃ , Li ₂ CO ₃ , anatase TiO ₂ , and KCl as a flux were thoroughly mixed for 10 minutes using a mortar. This mixture was kept in the atmosphere at 820 ° C. for 1 hour to melt KCl, and then baked at 1000 ° C. for 8 hours. Thereafter, the reaction product was gradually cooled to obtain a layered titanate. When this layered titanate was subjected to X-ray diffraction measurement using an X-ray diffractometer (RINT2100, manufactured by Rigaku Corporation), it was found to be K _0.8 Ti _1.73 Li _0.27 O _4. confirmed. Moreover, when the shape of this layered titanate was observed using a scanning electron microscope (S3600N manufactured by Hitachi High-Technologies Corporation), it was confirmed that the particles were fine particles having an average particle diameter of 15 μm.

Next, the layered titanate and 1 L of 0.5N hydrochloric acid were mixed and stirred with a stirrer at room temperature for 1 day. By this acid treatment, K ⁺ and Li ^{+ of} K _0.8 Ti _1.73 Li _0.27 O ₄ are replaced with H ₃ O ⁺ while maintaining the layered structure, and layered titanic acid (H _0.7 Ti _1.825 O ₄ · H ₂ O) was obtained. Thereafter, the layered titanic acid was washed with water and filtered.

(Production of single-layer titanate flakes)
Next, layered titanic acid and 0.5 mol of the nanosheeted amine species (basic substance) shown in Table 1 below were mixed, and water was further added so that the titanium concentration was 15% by mass. The obtained mixture was stirred with a stirrer at room temperature for 1 day to peel off a single layer to obtain an aqueous dispersion of single layer titanate flakes.

(Production of titanic acid flakes bonded with urethane resin)
100 g of the obtained aqueous dispersion of layered titanic acid and 43 g of urethane resin shown in Table 1 below are stirred and mixed for 1 hour, then heat-treated under the conditions shown in Table 1 below, and further stirred for 1 hour to obtain a titanic acid dispersed paste. Prepared. At this time, the exchange reaction between triethylamine and a basic substance was confirmed by evaporating and foaming triethylamine.

2. Preparation of glitter coating composition 143 g of the obtained titanic acid dispersion paste is added to 950 g of an acrylic resin (manufactured by DIC, trade name: Bernock WE310), and an isocyanate curing agent is used so that the mass ratio of acrylic / isocyanate is 80/20. (Product made by DIC, trade name: DNW5000) was added and mixed to prepare a glittering paint composition.

[Example 2-6]
A glittering paint composition was prepared in the same manner as in Example 1 except that the nanosheet-forming amine species described in Table 1 were used and the heat treatment was performed under the conditions described in Table 1.

[Comparative Example 1-3]
A glittering coating composition was prepared in the same manner as in Example 1 except that the urethane resin was not used, the heat treatment was not performed, and the nanosheeted amine species described in Table 1 were used.

[Comparative Example 4-10]
A glittering coating composition was prepared in the same manner as in Example 1 except that the urethane resin and the nanosheeted amine species described in Table 1 were used and the heat treatment was performed under the conditions described in Table 1.

<Preparation of glitter coating>
The resulting glittering coating composition was applied to a laminated coating plate of an electrodeposition coating, an intermediate coating, and a colored base coating so as to have a film thickness of 15 μm. After preheating at 80 ° C. for 3 minutes, a clear coating was laminated to a thickness of 35 μm. The clear paint was laminated to 35 to 60 μm. A laminated coating film was prepared by baking at 140 ° C. for 30 minutes. As the clear paint, an isocyanate curable clear paint (trade name: R-298 Clear, manufactured by Nippon Bee Chemical Co., Ltd.) using a low molecular weight curing agent was used.

  The design properties and adhesion of the glitter coating films obtained using the glitter paint compositions of Example 1-6 and Comparative Example 1-10 were evaluated using the following methods.

<Silky feeling evaluation test>
Using the multi-angle spectrocolorimeter (manufactured by X-Rite, portable multi-angle spectrocolorimeter MA68II), the light-receiving angle of 15 to 110 ° with respect to the obtained glittering coating film with respect to an incident angle of 45 °. The brightness (L ^* value) was measured, and the difference between the maximum value and the minimum value was evaluated as a flip-flop value (FF value). A higher FF value indicates better silky feeling.

<Adhesion test>
The adhesion of the resulting glittering coating film was evaluated by a cross-cut peel test described in JIS D0202-19889. In addition, it was set as the crosscut (2 mm square, 100 squares), and the cello tape (trademark) CT-24 (Nichiban Co., Ltd. product, width 24mm) was used as a tape.

  The obtained results are shown in Table 1.

<Water resistance test>
Distilled water or deionized water was placed in a constant temperature water bath, maintained at 40 ° C., and maintained for 240 hours in a state where at least half of the test piece was immersed in water. Then, remove the test specimen from the water tank, wipe off water droplets and dirt with a cloth, etc., and check for wrinkles, cracks, blistering, peeling, gloss reduction, discoloration, and blistering at room temperature within 24 hours. Evaluation was performed by a cross-cut peel test similar to the test.

  The glittering paint composition of the present invention is suitably applied to automobile paints and residential paints.

Claims (4)

A method for producing a glittering coating composition comprising a titanic acid flake to which a urethane resin is bonded and an acrylic resin,
(A) a step of mixing a layered titanate with an acid to obtain a hydrogen-type layered titanic acid having a layered structure maintained;
(B) mixing hydrogen-type layered titanic acid with at least one basic substance selected from dimethylethanolamine (DMEA), tetraethylammonium hydroxide (TEAH) and tetrapropylammonium hydroxide (TPAH); , Further mixing with water to obtain an aqueous dispersion containing a single layer of titanic acid flakes,
(C) An aqueous dispersion containing a single layer of titanic acid flakes is mixed with a urethane resin having an anionic hydrophilic group, and the resulting mixture is heated at 35 to 60 ° C. for 5 minutes or more to bond the urethane resin. Obtaining a dispersed paste of titanic acid flakes, and
A process of adding a dispersion paste of titanic acid flakes bonded with a urethane resin to an acrylic resin and adding an isocyanate curing agent to obtain a glittering coating composition
Including the above method. A method for producing a glittering coating composition comprising a titanic acid flake to which a urethane resin is bonded and an acrylic resin,
(A) a step of mixing a layered titanate with an acid to obtain a hydrogen-type layered titanic acid having a layered structure maintained;
(B) mixing hydrogen-type layered titanic acid with at least one basic substance selected from dimethylethanolamine (DMEA), tetraethylammonium hydroxide (TEAH) and tetrapropylammonium hydroxide (TPAH); , Further mixing with water to obtain an aqueous dispersion containing a single layer of titanic acid flakes,
(C) A water dispersion containing a single layer of titanic acid flakes is mixed with a urethane resin having an anionic hydrophilic group, and the resulting mixture is heated at 65 to 90 ° C. for 8 minutes or less to bond the urethane resin. Obtaining a dispersed paste of titanic acid flakes, and
A process of adding a dispersion paste of titanic acid flakes bonded with a urethane resin to an acrylic resin and adding an isocyanate curing agent to obtain a glittering coating composition
Including the above method. The method according to claim 1 or 2, wherein the anionic hydrophilic group of the urethane resin is neutralized with an amine. 4. A process according to claim 3, wherein the amine is triethylamine.

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