Indian Patents. 201127:A FLAKY PIGMENT FOR RESIN COMPOSITION

Title of Invention	A FLAKY PIGMENT FOR RESIN COMPOSITION
Abstract	A flaky pigment for resin composition, which is coated with a coupling agent and an organic compound such as herein described having a perfluoroalkyl group on the surface of the flaky pigment.

Full Text	WO 02/064682 PCT/EPGl/01682 DESCRIPTION FLAKY PIGMENTS Technical Field The present invention relates to a flaky pigment excellent in leafing properties and adhesion and in particular to a flaky pigment for coating and printing ink, which is coated with a coupling agent and an organic compound having a perfluoroalkyl group and is excellent in leafing properties and adhesion between flaky pigment particles and a coating layer. Background Art Heretofore, a large number pearlescent pigments and metal pigments having the shape of leaf, when incorporated into coating compositions etc., form coatings of design based on brightness by uniformly dispersing flaky pigment particles in coating layers. Recently, the development of various flaky pigments of design having brightness like plating is advanced by allowing flaky pigment particles represented by leafing aluminum flake pigment to float on the surface of a coating {leafing properties or plane orientation) to further improve the brightness of the coating. For example, with respect to metal pigments, a pigment comprising flake copper powder coated with stearic acid (JP-A 8-188731) and a pigment comprising aluminum flakes whose surface has been treated with alkyl WO 02/064682 PCT/EP01/01C82 phosphates (JP-A 11-57605) have been pro osed as pigments having leafing properties. Further, with respect to pearlescent pigments, a resin film comprising pearlescent pigments coated with a silane compound has been proposed (JP-A 7-62151). This silane coating pigment was used to raise leafing properties and compatibility between pigment particles and resin in the^resin film. Among these known flaky pigments, there are pigments showing excellent characteristics in leafing properties, but the interlaminar adhesion between the pigment particles and the coated film is weak, and accordingly, there is a defect in durability when used as coatings. That is, even if the known flaky pigment particles float on the surface of the coating to achieve a desired design by brightness based on their leafing properties, the interlaminar adhesion between the flaky pigment particles and a clear coating coated thereon for the purpose of protection is so low that the clear coating is easily removed upon attaching and pulling a cellophane tape or the like. Thus, such pigments used in a coating fail to achieve durability required of the coating. On one hand, it is also attempted that the adhesion between pigment particles and a clear coating layer is raised without reducing leafing properties by devising a coating technique in which just before coating, an organic solvent-type base WO 02/064682 PCT/EI)(n/01(iS2 coating containing a resin compos: -ion for coating is mixed with a dispersion of leafing aluminum flake pigments in an organic solvent (JP-A 11-128828). On the other hand, pigments treated with phosphate compounds having perfluoroalkyl groups (JP-A-5-i93153) or with silane compounds (JP-A 2,-218603) or pigments treated simultaneously with these compounds having jierfluoroalkyl groups and reactive organic silicon compounds (JP-A 8-217 989) are also proposed, but both of the pigments are developed for the purpose of improving the water- and oil-repellency of the pigments, and these are pigments used mainly for cosmetics. Disclosure of the Invention As a result of their eager study for developing a flaky pigment for coating or printing ink which is excellent in leafing properties and inter laminar adhesion between pigment particles and a protective coating, the present inventors found that a flaky pigment treated by coating the pigment with a coupling agent and a compound having a perfluoroalkyl group improves both leafing properties and interlaminar adhesion, and that it is excellent particularly as a pigment for coating and printing ink of which durability is required. That is, the present invention provides a novel flaky pigment for resin composition described in items 1 to 6 below, which is excellent in leafing properties and interlaminar WO 02/064682 PCT/EP01/01682 adhesion. 1. A flaky pigment for resin composition, which is coated with a coupling agent and an organic compound having a perfluoroalkyl group on the surface of the flaky pigment. 2. The flaky pigment for resin composition according to item 1 above, wherein the flaky pigment is one or more members selected from pearlescent pigments and metal pigments. 3. The flaky pigment for resin composition according to item 1 or 2 above, wherein the flaky pigment is a pigment in which hydrous zirconium oxide formed by hydrolysis of a zirconium compound in the presence of hypophosphite and/or a hydrous compound formed by hydrolysis of one or more water-soluble compounds of metals selected from cobalt, manganese and cerium has been deposited of the surface of a pearlescent pigment. 4. The flaky pigment for resin composition according to any one of items 1 to 3 above, wherein the organic compound having a perfluoroalkyl group is one or more members selected from compounds represented by the general formulae (I) 'to (III) below: phosphates having a perfluoroalkyl group, represented by the general formula (I): [Rf(CnH2nO)JyPO(OM)3_y (I) wherein Rf represents a straight-chain or branched C6 to cn perfluoroalkyl group or perfluoroalkyloxy group, M represents hydrogen, an alkali metal, ammonium and substituted ammonium, WO02/064682 PCT/EPOI/01682 n is from 1 to 4, m is from 0 to 10, and y is from 1 to 3; phosphates having a perfluoroalkyl group, represented by the general formula (II): (Rf SO2NRCnH2nO) yPO (OM) 3.r (II) wherein Rf represents a straight-chain or branched C6 to C21 perfluoroalkyl group or perfluoroalkyloxy group, M represents hydrogen, an alkali metal, ammonium or substituted ammonium, R represents hydrogen or a Ct to C3 alkyl group, n is from 1 to 4, m is from 0 to 10, and y is from 1 to 3; and perfluoroalkyl silane represented by the general formula (III): Rf(CH2)nSiX5 (III) wherein Rf represents a straight-chain or branched Cx to Cl2 perfluoroalkyl group, X may be the same or different and represents an alkoxy group, a halogen group or an alkyl group, provided that not all X groups should be alkyl groups, and n is from 1 to 5. 5. The flaky pigment for resin composition according to any one of items 1 to 4 above, wherein the coupling agent is one or more members selected from a silane coupling agent, a titanium-based coupling agent and a zirconium-based coupling agent. 6. The flaky pigment for resin composition according to any one of items 1 to 5 above, wherein the coverage amount of each of the coupling agent and the compounds represented by the WO 02/064682 PCT/EP01/01682 general formulae (I) to (III) is 0.05 to 20 % by weight relative to the flaky pigment. Best Mode Carrying Out the Invention Hereinafter, the embodiments of the flaky pigment for resin composition according to the present invention are described item by item in more detail. 1) The flaky pigment Although the flaky pigment used in the flaky pigment for resin composition according to the present invention is not particularly limited, the present invention is directed in particular to flaky pearlescent pigments and metal pigments used for coating or printing ink. Here, the pearlescent pigments and metal pigments are classified according to the different concepts of function and material, so it should be noted that the same pigment or base material may fall under both the concepts. The pearlescent pigments include single or complex metal oxide-coated mica based on flaky mica (natural and synthetic mica), for example, various kinds of titanium oxide-coated mica, iron oxide-coated mica, mica coated with a metal complex oxide consisting of titanium and an acid, and cobalt titanate-coated mica; metal oxide-coated graphite flakes based on flaky graphite, for example, titanium dioxide-coated graphite flakes; and various kinds of metal oxide-coated alumina flakes WO 02/064682 PCT/EP01/01682 7 based on flaky.alumina, for example, titanium dioxide-coated alumina flakes and iron oxide-coated alumina flakes, as well as metal oxide-coated silica flakes, metal oxide-coated glass flakes, metal-coated glass flakes, metal oxide-coated micaceous iron oxide, titanium dioxide-coated micaceous iron oxide, metal oxide-coated plate barium sulf ate etc. The metal oxide-coated mica etc. are commercially available as Iriodin® from E. Merck etc. Further, weatherable pearlescent pigments to which hydrous zirconium oxide formed by hydrolysis of a zirconium compound in the presence of hypophosphite and/or a hydrous oxide formed by hydrolysis of one or more water-soluble compounds of metals selected from cobalt, manganese and cerium has been deposited according to the present applicant On the other hand, the metal pigments include e.g. aluminum flakes, micaceous iron oxide, brass, stainless steel flakes, titanium flakes, boron nitride flakes, copper powder etc. Tne size of these flaky pigments is not particularly limited, and pigments with a size achieving desired utilities and desired hues and brightness are suitably selected from usually used pigments having a particle diameter of 2 to 200 JUTV and a thickness of 0.2 to 1.0 ^un. WO 02/064682 PCT/EP01/01682 2) The organic compound having a perfluoroalkyl group As the compound having a perfluoroalkyl group, one or more compounds selected from phosphates represented by the general formula (I) or (II) and silane compounds represented by the general formula (III) are used in combination. [Rf(CBHaBO)B],PO (Rf SO2NRCnH2nO) yPO {OM} >_y (II) wherein Rf represents a straight-chain or branched C6 to C21 perfluoroalkyl group or perfluoroalkyloxy group, M represents hydrogen, an alkali metal, ammonium or substituted ammonium, R represents hydrogen or a Cj to C3 alkyl group, n is from 1 to 4, m is from 0 to 10, and y is from 1 to 3. The substituted ammonium represented by M in both the formulae includes alkanol amines such as monoethanol amine and diethanol amine or basic amino acids. Typical compounds of the general formulae (I) and (II) above include (CF3 (CF3) 7CH2CH2O) ,PO [ ONH2 (CH2CH2OH), ] , ( CFj (CF2) 7SO2N (CjH7) C2H,O) 2P0 (OH) etc. Rf(CH2)nSiX, (III) wherein Rf represents a straight-chain or branched C: to C12 perfluoroalkyl group, X may be the same or different and represents an alkoxy group, a halogen atom and an alkyl group, provided that not all X groups should be alkyl groupsf and n is from 1 to 5. Examples of silane compounds of the general formula (III) WO 02/064682 PCT/EP01/01682 9 are as follows: CF3(CF2)7(CH2)2Si(OCH3)3 CF3(CF2)u(CH3)2SiCl3 CF3(CF2)4(CH2)2SiCl3 CF3(CF2)3SiCl3 CF3(CF2)10(CH2)2Si(OCH3)3 CFjtCFjJsCCHjJjSijOCHjJj CF3(CF2),(CH2)2Si(OC2Hs)3 CF3(CF2)7(CH2)2Si(OC2Hs)3 CF3(CF2)4(CH2)2SX(OC2H5)3 CF3(CF2)2(CH2)2Si(OC2H5)3 CF3(CH2)2Si(OCH3)3 3) The coupling agent The coupling agent used in the present invention is not particularly limited, and it is possible to use a silane-based coupling agent, a titanium-based coupling agent and a zirconium-based coupling agent, and the silane coupling agent is particularly preferable from an economical point of view. Typical compounds of each coupling agent are as follows: A) Silane-based coupling agent Methacryloxy alkoxypropyl trimethoxysilane, Y-(2-aminoethyl)aminopropyl trimethoxys ilane, Y-(2-aminoethyl)aminopropylmethy1 dimethoxys ilane, Y-methacryloxypropyl trimethoxysilane, N-fJ- (N-vinylbenzylaminoethyl) -Y-aminopropyl WO 02/064682 PCT/EP0I/0I682 10 trimethoxysilane, Y-glycidoxypropyl trimethoxysilane, Y-mercaptopropyl trimethoxysilane, vinyl triacetoxysilane, Y-chloropropyl trimethoxysilane, octadecyldimethyl[3-(trimethoxys ilyl)propyl]ammonium chloride, Y-mercaptopropylmethyl dimethoxycine, methyl trichlorosilane, dimethyl dichlorosilane, trimethyl chlorosilane, and vinyl trimethoxysilane. In particular, Y~ trimethoxysilane, Y-methacryloxypropyl trimethoxysilane, and Y-glycidoxypropyl trimethoxysilane are preferable. B) Titanium-based coupling agent Tetra(2,2-diallyloxymethyl-l-butyl)bis(di-tridecyl) phosphite) titanate, bis(dioctylpyrophosphate) oxyacetate titanate, and isopropyltri(N-aminoester-aminoethyl) titanate. C) Zircoaluminate-based coupling agent Carboxyzircoaluminate and methacryloxyzircoaluminate. 4) Coverage amount The coverage amount of each of the coupling agent and the WO 02/064682 PCT/EP01/01682 n compounds having a perfluoroalkyl group represented by the general formulae (I) to (III) above may be the same and is 0.05 to 20 % by weight, preferably 0.05 to 15 % by weight, relative to the flaky pigment. If the coverage amount of each of these components is less than 0.05 % by weight, it is not possible to achieve suf fici*3t leafing effects and adhesion to a coating layer. On the other hand, a coverage amount exceeding 20 % by weight, although the desired leafing effects etc. can thereby be achieved, is meaningless from an economical point of view because no further improvement of the effects can be expected. 5) Process Either a wet process or a dry process used in a conventional process for pigments can be used as the process for producing the flaky pigment for resin composition according to the present invention. However, because pigments having even characteristics can be obtained easily and effectively and subsidiary materials can be easily handled, the wet process in an aqueous system is most appropriate as the process for producing the flaky pigment according to the present invention. One example of the process by the wet process is outlined as follows. A flaky pigment is suspended in a water solvent, and first a coupling agent is added or its solution is added dropwise to the suspension. Then, a phosphate having a perfluoroalkyl group or a silane compound is added or its WO 02/064682 PCT/EPOl/01682 12 solution is added dropwise thereto. During these coating treatments, the solution is adjusted to pH and temperature which are suitable for each material to be handled, and each material is stirred so that the pigment is uniformly coated therewith. After the coating treatments/ the pigment is filtered, washed with water and dried in a usual manner to give the desired pigment. With respect to the order of addition of the coupling agent and the compound having a perfluoroalkyl group, it is preferable to first coat the pigment with the coupling agent as outlined above because the pigment with even characteristics can be easily obtained. However, it is also possible to add both the compounds simultaneously or as a mixture. 6) Use of the flaky pigment as a pigment for resin composition As described above, the flaky pigment of the present invention is an material exhibiting its effects upon incorporation into a coating composition in an organic solvent system, a coating composition in an aqueous system and a composition, typically printing ink etc. containing resin as an component. Accordingly, the flaky pigment of the present invention can be used as a pigment added to coatings applied to various materials such as paper, wood plates, metal plates, cloth, leather and plastics and to a composition such as printing ink containing resin. WO 02/064682 PCT/EPOI/01682 13 Examples Hereinafter, the present invention is described in more detail by reference to the Examples, Comparative Examples and Test Example, which however are not intended to limit the present invention. Example 1 An aqueous solution containing 5.68 g sodium hypophosphite (NaH2PO2H2O) was gradually added to 3 weight-% aqueous solution containing 5.76 g zirconium oxychloride (ZrOCl2-8H2O) under stirring at room temperature so as not to cause white precipitates, to prepare a transparent aqueous solution. Then, 6 .0 g of 35 to 37 % aqueous hydrochloric acid solution was added to it to prepare a mixed solution of zirconium oxychloride and sodium hypophosphite. Separately, 100 g rutile titanium oxide-coated mica titanium flakes (IRIODIN225 Rutile Blue, a product of E. Merck) having a particle size of 10 to 60 \m exhibiting a blue reflection color and a yellow transmission color was suspended in 1000 ml water, and the temperature was raised to 75 °C under stirring- The suspension was adjusted to pH 3 with hydrochloric acid, and 1.14 g of 10 weightr% aqueous cerium chloride (CeCl3-7H2O) was added thereto, and said mixed solution of zirconium oxychloride and sodium hypophosphite was added dropwise thereto for about 1 hour, during which the suspension was kept at pH 3 with 32 weight-% aqueous NaOH solution. After WO 02/064682 PCT/EP01/01682 14 the whole mixed solution was added dropwise thereto, the mixture was stirred at 75 °C for 30 minutes, then 2 g y-methacryloxypropyl trimethoxysilane (CH2=C(CH3)COO(CH2)3Si{OCH3)3 (Toray Dow Corning Ltd./SZ6030) was added thereto, and the mixture was stirred at 75 °C for 15 minutes and its pH was raised to 7.0 with NaOH. 10 weight-% aqueous solution of 10.00 g af. perfluoroalkyl phosphate (CF3 (CF2) 7CH2CH2O) 2PO [ ONH2 (CH2CH2OH) 2 ] (UNIDIN TGI 01, Daikin Industries, Ltd.) was added dropwise to the suspension for about 1 hour, and the mixture was stirred at 75 °C for 30 minutes . The resulting solid product in the suspension was filtered, washed with water and dried at 13 0 °C. A pearlescent pigment excellent in dispersibility with powder exhibiting a blue reflection color and a yellow transmission color was obtained in the procedure described above. When this pigment was suspended in a low polar organic solvent such as toluene and xylene, the pigment particles floated on the surface of the solvent and were orientated densely, whereupon a designing ability excellent in brightness with the outstanding reflection color of the pearlescent pigment was confirmed. Example 2 Using 100 g of the same rutile titanium oxide-coated mica titanium flakes (IRIODIN 225 Rutile Blue, a product of E. Merck) having a particle size of 10 to 60 nm exhibiting a blue WO 02/064682 PCT/EP01/1H682 15 reflection color and a yellow transmission color as in Example 1, the same procedure using the same amounts of the same materials as in Example 1 was conducted except that the perfluoroalkyl phosphate was replaced by 2 g perfluoroalkyl silane CFjtCFjMCHjJjSifOCHjCH,), (Toray Dow Corning Ltd./AY43-158E). A pearlescent pigment excellent in dispersibility with powder exhibiting a blue reflection color and a yellow transmission color was obtained in the procedure described above. When this pigment was suspended in a low polar organic solvent such as toluene and xylene, the pigment particles floated on the surface of the solvent and were orientated densely, whereupon a designing ability excellent in brightness with the outstanding reflection color of the pearlescent pigment was confirmed. Example 3 An aqueous solution containing 5.68 g sodium hypophosphite {NaH2PO:-H3O) was gradually added to 3 weight-% aqueous solution containing 5.76 g zirconium oxychloride (ZrOClj-8H2O) under stirring at room temperature so as not to cause white precipitates, to prepare a transparent aqueous solution. Then, 6.0 g of 35 to 37 % aqueous hydrochloric acid solution was added to it to prepare a mixed solution of zirconium oxychloride and sodium hypophosphite. Separately, 100 g iron oxide-coated mica flakes (IRIODIN WO 02/064682 PCT7EP01/01682 16 504 Red, a product of E. Merck) having a particle size of 10 to 60 fxm exhibiting a wine red reflection color was suspended in 1000 ml water, and the temperature was raised to 75 °C under stirring. The suspension was adjusted to pH 3 with hydrochloric acid, and said mixed solution of zirconium oxychloride and sodium hypophosphite was added dropwise thereto for about 1 hour, during which the suspension was kept at pH 3 with 32 weight-% aqueous NaOH solution. After the whole mixed solution was added dropwise thereto, the mixture was stirred at 75 °C for 30 minutes, then 2 g y-niethacryloxypropyl trimethoxysilane (Toray Dow Corning Ltd./SZ6030) was added thereto, and the mixture was stirred at 75 °C for 15 minutes and its pH was raised to 7.0 with NaOH. 10 weight-% aqueous solution of 5-00 g of perfluoroalkyl phosphate (UNIDIN TG101, Daikin Industries, Ltd.) was added dropwise to the suspension for about 1 hour, and the mixture was stirred at 75 °C for 30 minutes. The resulting solid product in the suspension was filtered, washed with water and dried at 130 °C. A pearlescent pigment excellent in dispersibility with powder exhibiting a wine red reflection color was obtained in the procedure described above. when this pigment was suspended in a low polar organic solvent such as toluene and xylene, the pigment particles floated on the surface of the solvent and were orientated densely, whereupon a designing ability excellent in brightness with the outstanding WO 02/064682 I>CT/EP" 1/01682 17 reflection color of the pearlescent pigment was confirmed. Comparative Examples Comparative Example 1 Using 100 g of the same rutile titanium oxide-coated mica titanium flakes (IRIODIN 225 Rutile Blue, a product of E. Merck) having a particle size of 10 to 60 ^m exhibiting a blue reflection color and a yellow transmission color as in Example 1/ a pigment was obtained in the same manner using the same amounts of the same materials as in Example 1 except that the perfluoroalkyl phosphate was not used. Comparative Example 2 Using 100 g of the same rutile titanium oxide-coated mica titanium flakes (IRIODIN 225 Rutile Blue, a product of E. Merck) having a particle size of 10 to 60 ^m exhibiting a blue reflection color and a yellow transmission color as in Example 1, a pigment was obtained in the same manner using the same amounts of the same materials as in Example 1 except that the y-methacryloxypropyl trimethoxysilane was not used. Comparative Example 3 Using 100 g of the same iron oxide-coated mica flakes (IRIODIN 504 Red, a product of E. Merck) having a particle size of 10 to 60 ^m exhibiting a wine red reflection color as in Example 3, a pigment was obtained in the same manner using the same amounts of the same materials as in Example 3 except that the perfluoroalkyl phosphate was not used. WO 02/064682 PCT/EP01/01682 18 Comparative Example 4 Using 100 g of the same iron oxide-coated mica flakes (IRIODIN 504 Red, a product of E. Merck) having a particle size of 10 to 60 jim exhibiting a wine red reflection color as in Example 3, a pigment was obtained in the same manner using the same amounts of the same materials as in Example 3 except that the Y-methacryloxypropyl trimethoxysilane was not used. Test Examples The pigments obtained in the Examples and the Comparative Examples were examined in each of the following tests using test methods described below. The results of each test are collectively shown in Table 1. 1) Water resistance test (hot-water immersion test) A thermosetting acrylic melamine resin (a mixture of Acrydic 47-712 and Super Beccamin G821-60 at a ratio of 7 : 3 by weight, Dainippon Ink and Chemicals, Inc.) was mixed at a concentration of 10 % by weight was applied at a dry film thickness of about 15 ^m on a zinc phosphate-treated steel plate (7 cmxl5 cm) having been coated with black enamel at a dry film thickness of about 20 \m and baked at 160 °C for 20 minutes, and the plate was left for 5 minutes and coated by air spraying with 7 weight-% dispersion of the resulting pigment in xylene, left for 10 minutes and cured by heating at 140 °C for 30 minutes. The cured coated face was coated with a top clear coating of a thermosetting acrylic melamine resin (a mixture of Acrydic WO 02/064682 PCT/EP01/0I682 19 47-179 and Super Beccamin L117-60 at a ratio of 7 : 3 by weight, Dainippon Ink and Chemicals, Inc.) at a dry film thickness of about 30 mn, left for 10 minutes and cured by heating at 140 °c for 30 minutes. The test plate produced in the method described above was immersed in hot water at 80 °C and kept therein for 8 hours, and then the temperature of hot water was decreased to room temperature, and the test plate was removed and visually checked to examine the change of its appearance. Numerical values in Table 1 indicate that whitening/shrinkage performance is" inferior in the order of from 1C to 1. 2) Adhesion The coated face of the test plate prepared in the water resistance test was cut such that the cut reached the base material whereby 100 cut-line squares with a size of 1 mmxl mm were made thereon, and a cellophane tape was attached to the surface and rapidly peeled off, and then the coated face was observed. O indicates that 9 or less squares were removed, and x indicates that 10 or more squares were removed. 3) Hue measurement (chromatic value) C-value (chromatic value) was measured at an angle of incidence of 25° and at a light-receiving angle of 20° with a varied-angle color measurement meter GCMS3 (Murakami Shikisai WO 02/064682 20 PCT/EP01/01682 Co., Ltd.)- The C value is indica the intensity of reflection color of the pearlescent pigment, and a large C value indicates stronger color. This is correlated with the denseness of particles due to the leafing effects of the pigment. 4) Designing ability The coating was visually evaluated. In Table 1, O indicates a designing ability excellent in plating-like brightness, and x indicates the designing ability of a usual pearlescent pigment. Table 1 Test Sample Amount of Group (A) Used Amount of Group (B) Used Water Resistance Test Whitening/ shrinkaqe Adhesion Hue Measurement C value Designing Ability Example 1 10 weiqht-% 2 weiqht-% 6/7 0 80.1 0 Example 2 2 weiqht-% 2 weiqht-% 6/7 0 84.1 0 Example 3 S weiqht-% 2 weiqht-% 6/7 0 80.6 o Comparative Example 1 ^^ 2 weight-% 6/7 0 68.0 X Comparative Examole2 1Oweight-% ^^ SJ6 X 80.2 0 Comparative Example 3 ^^ 2 weight-% 6/7 0 62.3 X Comparative Example 4 5 weight-% 5/6 X 79.8 0 1) Group (A) indicates the amount of the organic compound having a perfluoroalk yl group in the Examples and Comparative Examples 2) Group (8) indicates the amount of the coupling agent in the Examples and Comparative Examples Industrial Applicability It was found in the present invention that a novel flaky pigment having the leafing effects of flaky pigment particles on a coating and being excellent in the interlaminar adhesion WO 02/064682 PCT/EP01/01682 21 between flaky pigment particles and a coated film is obtained by coating the surface of a flaky pigment with a combination of a coupling agent and an organic compound having a perfluoroalkyl group. By having such properties, the flaky pigment particles are orientated densely on the coating, thus reinforcing plating-like brightness and effectively exhibiting the pearlescence of particularly a pearlescent pigment. Further, the effect of improving the interlaminar adhesion prevents the exfoliation of a clear coating thereby achieving lasting brightness and improving the durability of a coating or printing ink. -22- 1. A flaky pigment for resin composition, which Is coated with a coupling agent and an organic compound such as herein described haying a perfluoroalkyl group on the surface of the flaky pigment. 2. The flaky pigment for rasin composition according to claim 1, wherein the flaky pigment is one or more members selected from peariescent pigments and metal pigments such as herein described. 3. The flaky pigment for resin composition according to claim 1 or 2, wherein the flaky pigment is a pigment in which hydrous zirconium oxide formed by hydrolysis of a zirconium compound in ihe presence of hypophosphite, and/or a hydrous compound formed by hydrolysis of one or more wafer-soluble compounds of metal selected from cobalt, manganese and cerium has been deposited on the surface of a peariescent pigment. 4. The flaky pigment for resin composition according to any one of claims 1 to 3, wherein the organic compound having a perfluoroalkyi group is one or more members selected from compounds represented by the general formulae (I) to (IID below: phosphetes having a perfluoroelkyl group, represented by the general formula (I): [Rf(CnH2nO)tTJ,PO(O?^)3.y (I) wherein Rf represents a straight-chain or branched Cg to C21 perfluoroafkyl group or perfluoroalkyloxy group, M represents hydrogen, an alkali metal, ammonium and substituted ammonium, WO 02/064682 PCT/EPO1/O16S2 23 n is from 1 to 4, m is from 0 to 10, and y is from 1 to 3; phosphates having a perfluoroalkyl group, represented by the general formula {II): (Rf SO2NRCnH2nO) ,PO (OM) 3_y (II) wherein Rf represents a straight-chain or branched Cfi to c31 perfluoroalkyl group or perfluoroalkyloxy group, M represents hydrogen, an alkali metal, ammonium or substituted ammonium, R represents hydrogen or a Ct to C3 alkyl group, n is from 1 to 4, m is from 0 to 10, and y is from 1 to 3; and perfluoroalkyl silane represented by the general formula (III): Rf(CH2)nSiX3 (III) wherein Rf represents a straight-chain or branched Cx to c12 perfluoroalkyl group, X may be the same or different and represents an alkoxy group, a halogen group or an alkyl group, provided that not all X groups should be alkyl groups, and n is from 1 to 5. 5. The flaky pigment for resin composition according to any one of claims 1 to 4, wherein the coupling agent is one or more members selected from a silane coupling agent, a titanium-based coupling agent and a zirconium-based coupling agent. 6. The flaky pigment for resin composition according to any one of claims 1 to 5, wherein the coverage amount of each of the coupling agent and the compounds represented by WO 02/064682 24 PCT/EP01/0J682 the general formulae (I) to (III) is 0.05 to 20 % by weight relative to the flaky pigment. A flaky pigment for resin composition, which is coated with a coupling agent and an organic compound such as herein described having a perfluoroalkyl group on the surface of the flaky pigment.

Full Text

WO 02/064682 PCT/EPGl/01682
DESCRIPTION FLAKY PIGMENTS
Technical Field
The present invention relates to a flaky pigment excellent in leafing properties and adhesion and in particular to a flaky pigment for coating and printing ink, which is coated with a coupling agent and an organic compound having a perfluoroalkyl group and is excellent in leafing properties and adhesion between flaky pigment particles and a coating layer.
Background Art
Heretofore, a large number pearlescent pigments and metal pigments having the shape of leaf, when incorporated into coating compositions etc., form coatings of design based on brightness by uniformly dispersing flaky pigment particles in coating layers. Recently, the development of various flaky pigments of design having brightness like plating is advanced by allowing flaky pigment particles represented by leafing aluminum flake pigment to float on the surface of a coating {leafing properties or plane orientation) to further improve the brightness of the coating. For example, with respect to metal pigments, a pigment comprising flake copper powder coated with stearic acid (JP-A 8-188731) and a pigment comprising aluminum flakes whose surface has been treated with alkyl

WO 02/064682 PCT/EP01/01C82
phosphates (JP-A 11-57605) have been pro osed as pigments having leafing properties.
Further, with respect to pearlescent pigments, a resin film comprising pearlescent pigments coated with a silane compound has been proposed (JP-A 7-62151). This silane coating pigment was used to raise leafing properties and compatibility between pigment particles and resin in the^resin film.
Among these known flaky pigments, there are pigments showing excellent characteristics in leafing properties, but the interlaminar adhesion between the pigment particles and the coated film is weak, and accordingly, there is a defect in durability when used as coatings. That is, even if the known flaky pigment particles float on the surface of the coating to achieve a desired design by brightness based on their leafing properties, the interlaminar adhesion between the flaky pigment particles and a clear coating coated thereon for the purpose of protection is so low that the clear coating is easily removed upon attaching and pulling a cellophane tape or the like. Thus, such pigments used in a coating fail to achieve durability required of the coating.
On one hand, it is also attempted that the adhesion between pigment particles and a clear coating layer is raised without reducing leafing properties by devising a coating technique in which just before coating, an organic solvent-type base

WO 02/064682 PCT/EI)(n/01(iS2
coating containing a resin compos: -ion for coating is mixed with a dispersion of leafing aluminum flake pigments in an organic solvent (JP-A 11-128828).
On the other hand, pigments treated with phosphate compounds having perfluoroalkyl groups (JP-A-5-i93153) or with silane compounds (JP-A 2,-218603) or pigments treated simultaneously with these compounds having jierfluoroalkyl groups and reactive organic silicon compounds (JP-A 8-217 989) are also proposed, but both of the pigments are developed for the purpose of improving the water- and oil-repellency of the pigments, and these are pigments used mainly for cosmetics.
Disclosure of the Invention
As a result of their eager study for developing a flaky pigment for coating or printing ink which is excellent in leafing properties and inter laminar adhesion between pigment particles and a protective coating, the present inventors found that a flaky pigment treated by coating the pigment with a coupling agent and a compound having a perfluoroalkyl group improves both leafing properties and interlaminar adhesion, and that it is excellent particularly as a pigment for coating and printing ink of which durability is required.
That is, the present invention provides a novel flaky pigment for resin composition described in items 1 to 6 below, which is excellent in leafing properties and interlaminar

WO 02/064682 PCT/EP01/01682
adhesion.
1. A flaky pigment for resin composition, which is coated with
a coupling agent and an organic compound having a
perfluoroalkyl group on the surface of the flaky pigment.
2. The flaky pigment for resin composition according to item
1 above, wherein the flaky pigment is one or more members
selected from pearlescent pigments and metal pigments.
3. The flaky pigment for resin composition according to item
1 or 2 above, wherein the flaky pigment is a pigment in which
hydrous zirconium oxide formed by hydrolysis of a zirconium
compound in the presence of hypophosphite and/or a hydrous
compound formed by hydrolysis of one or more water-soluble
compounds of metals selected from cobalt, manganese and cerium
has been deposited of the surface of a pearlescent pigment.
4. The flaky pigment for resin composition according to any
one of items 1 to 3 above, wherein the organic compound having
a perfluoroalkyl group is one or more members selected from
compounds represented by the general formulae (I) 'to (III)
below:
phosphates having a perfluoroalkyl group, represented by the general formula (I):
[Rf(CnH2nO)JyPO(OM)3_y (I)
wherein Rf represents a straight-chain or branched C6 to cn perfluoroalkyl group or perfluoroalkyloxy group, M represents hydrogen, an alkali metal, ammonium and substituted ammonium,

WO02/064682 PCT/EPOI/01682
n is from 1 to 4, m is from 0 to 10, and y is from 1 to 3; phosphates having a perfluoroalkyl group, represented by the general formula (II):
(Rf SO2NRCnH2nO) yPO (OM) 3.r (II)
wherein Rf represents a straight-chain or branched C6 to C21 perfluoroalkyl group or perfluoroalkyloxy group, M represents hydrogen, an alkali metal, ammonium or substituted ammonium, R represents hydrogen or a Ct to C3 alkyl group, n is from 1 to 4, m is from 0 to 10, and y is from 1 to 3; and perfluoroalkyl silane represented by the general formula (III):
Rf(CH2)nSiX5 (III)
wherein Rf represents a straight-chain or branched Cx to Cl2 perfluoroalkyl group, X may be the same or different and represents an alkoxy group, a halogen group or an alkyl group, provided that not all X groups should be alkyl groups, and n is from 1 to 5.
5. The flaky pigment for resin composition according to any
one of items 1 to 4 above, wherein the coupling agent is one
or more members selected from a silane coupling agent, a
titanium-based coupling agent and a zirconium-based coupling
agent.
6. The flaky pigment for resin composition according to any
one of items 1 to 5 above, wherein the coverage amount of each
of the coupling agent and the compounds represented by the

WO 02/064682 PCT/EP01/01682
general formulae (I) to (III) is 0.05 to 20 % by weight relative to the flaky pigment.
Best Mode Carrying Out the Invention
Hereinafter, the embodiments of the flaky pigment for resin composition according to the present invention are described item by item in more detail. 1) The flaky pigment
Although the flaky pigment used in the flaky pigment for resin composition according to the present invention is not particularly limited, the present invention is directed in particular to flaky pearlescent pigments and metal pigments used for coating or printing ink. Here, the pearlescent pigments and metal pigments are classified according to the different concepts of function and material, so it should be noted that the same pigment or base material may fall under both the concepts.
The pearlescent pigments include single or complex metal oxide-coated mica based on flaky mica (natural and synthetic mica), for example, various kinds of titanium oxide-coated mica, iron oxide-coated mica, mica coated with a metal complex oxide consisting of titanium and an acid, and cobalt titanate-coated mica; metal oxide-coated graphite flakes based on flaky graphite, for example, titanium dioxide-coated graphite flakes; and various kinds of metal oxide-coated alumina flakes

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7
based on flaky.alumina, for example, titanium dioxide-coated alumina flakes and iron oxide-coated alumina flakes, as well as metal oxide-coated silica flakes, metal oxide-coated glass flakes, metal-coated glass flakes, metal oxide-coated micaceous iron oxide, titanium dioxide-coated micaceous iron oxide, metal oxide-coated plate barium sulf ate etc. The metal
oxide-coated mica etc. are commercially available as Iriodin® from E. Merck etc.
Further, weatherable pearlescent pigments to which hydrous zirconium oxide formed by hydrolysis of a zirconium compound in the presence of hypophosphite and/or a hydrous oxide formed by hydrolysis of one or more water-soluble compounds of metals selected from cobalt, manganese and cerium has been deposited according to the present applicant On the other hand, the metal pigments include e.g. aluminum flakes, micaceous iron oxide, brass, stainless steel flakes, titanium flakes, boron nitride flakes, copper powder etc.
Tne size of these flaky pigments is not particularly limited, and pigments with a size achieving desired utilities and desired hues and brightness are suitably selected from usually used pigments having a particle diameter of 2 to 200 JUTV and a thickness of 0.2 to 1.0 ^un.

WO 02/064682 PCT/EP01/01682
2) The organic compound having a perfluoroalkyl group
As the compound having a perfluoroalkyl group, one or more compounds selected from phosphates represented by the general formula (I) or (II) and silane compounds represented by the general formula (III) are used in combination.
[Rf(CBHaBO)B],PO (Rf SO2NRCnH2nO) yPO {OM} >_y (II)
wherein Rf represents a straight-chain or branched C6 to C21 perfluoroalkyl group or perfluoroalkyloxy group, M represents hydrogen, an alkali metal, ammonium or substituted ammonium, R represents hydrogen or a Cj to C3 alkyl group, n is from 1 to 4, m is from 0 to 10, and y is from 1 to 3. The substituted ammonium represented by M in both the formulae includes alkanol amines such as monoethanol amine and diethanol amine or basic amino acids.
Typical compounds of the general formulae (I) and (II) above include (CF3 (CF3) 7CH2CH2O) ,PO [ ONH2 (CH2CH2OH), ] , ( CFj (CF2) 7SO2N (CjH7) C2H,O) 2P0 (OH) etc.
Rf(CH2)nSiX, (III)
wherein Rf represents a straight-chain or branched C: to C12 perfluoroalkyl group, X may be the same or different and represents an alkoxy group, a halogen atom and an alkyl group, provided that not all X groups should be alkyl groupsf and n is from 1 to 5.
Examples of silane compounds of the general formula (III)

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9
are as follows:
CF3(CF2)7(CH2)2Si(OCH3)3
CF3(CF2)u(CH3)2SiCl3
CF3(CF2)4(CH2)2SiCl3
CF3(CF2)3SiCl3
CF3(CF2)10(CH2)2Si(OCH3)3
CFjtCFjJsCCHjJjSijOCHjJj
CF3(CF2),(CH2)2Si(OC2Hs)3
CF3(CF2)7(CH2)2Si(OC2Hs)3
CF3(CF2)4(CH2)2SX(OC2H5)3
CF3(CF2)2(CH2)2Si(OC2H5)3
CF3(CH2)2Si(OCH3)3
3) The coupling agent
The coupling agent used in the present invention is not
particularly limited, and it is possible to use a silane-based
coupling agent, a titanium-based coupling agent and a
zirconium-based coupling agent, and the silane coupling agent
is particularly preferable from an economical point of view.
Typical compounds of each coupling agent are as follows:
A) Silane-based coupling agent
Methacryloxy alkoxypropyl trimethoxysilane,
Y-(2-aminoethyl)aminopropyl trimethoxys ilane,
Y-(2-aminoethyl)aminopropylmethy1 dimethoxys ilane,
Y-methacryloxypropyl trimethoxysilane,
N-fJ- (N-vinylbenzylaminoethyl) -Y-aminopropyl

WO 02/064682 PCT/EP0I/0I682
10
trimethoxysilane,
Y-glycidoxypropyl trimethoxysilane, Y-mercaptopropyl trimethoxysilane, vinyl triacetoxysilane,
Y-chloropropyl trimethoxysilane,
octadecyldimethyl[3-(trimethoxys ilyl)propyl]ammonium chloride,
Y-mercaptopropylmethyl dimethoxycine, methyl trichlorosilane, dimethyl dichlorosilane,
trimethyl chlorosilane, and vinyl trimethoxysilane.
In particular, Y~ trimethoxysilane, Y-methacryloxypropyl trimethoxysilane, and Y-glycidoxypropyl trimethoxysilane are preferable.
B) Titanium-based coupling agent
Tetra(2,2-diallyloxymethyl-l-butyl)bis(di-tridecyl) phosphite) titanate,
bis(dioctylpyrophosphate) oxyacetate titanate, and isopropyltri(N-aminoester-aminoethyl) titanate.
C) Zircoaluminate-based coupling agent
Carboxyzircoaluminate and methacryloxyzircoaluminate. 4) Coverage amount
The coverage amount of each of the coupling agent and the

WO 02/064682 PCT/EP01/01682
n
compounds having a perfluoroalkyl group represented by the general formulae (I) to (III) above may be the same and is 0.05 to 20 % by weight, preferably 0.05 to 15 % by weight, relative to the flaky pigment.
If the coverage amount of each of these components is less than 0.05 % by weight, it is not possible to achieve suf fici*3t leafing effects and adhesion to a coating layer.
On the other hand, a coverage amount exceeding 20 % by weight, although the desired leafing effects etc. can thereby be achieved, is meaningless from an economical point of view because no further improvement of the effects can be expected. 5) Process
Either a wet process or a dry process used in a conventional process for pigments can be used as the process for producing the flaky pigment for resin composition according to the present invention. However, because pigments having even characteristics can be obtained easily and effectively and subsidiary materials can be easily handled, the wet process in an aqueous system is most appropriate as the process for producing the flaky pigment according to the present invention.
One example of the process by the wet process is outlined as follows. A flaky pigment is suspended in a water solvent, and first a coupling agent is added or its solution is added dropwise to the suspension. Then, a phosphate having a perfluoroalkyl group or a silane compound is added or its

WO 02/064682 PCT/EPOl/01682
12
solution is added dropwise thereto. During these coating treatments, the solution is adjusted to pH and temperature which are suitable for each material to be handled, and each material is stirred so that the pigment is uniformly coated therewith. After the coating treatments/ the pigment is filtered, washed with water and dried in a usual manner to give the desired pigment.
With respect to the order of addition of the coupling agent and the compound having a perfluoroalkyl group, it is preferable to first coat the pigment with the coupling agent as outlined above because the pigment with even characteristics can be easily obtained. However, it is also possible to add both the compounds simultaneously or as a mixture. 6) Use of the flaky pigment as a pigment for resin composition
As described above, the flaky pigment of the present invention is an material exhibiting its effects upon incorporation into a coating composition in an organic solvent system, a coating composition in an aqueous system and a composition, typically printing ink etc. containing resin as an component. Accordingly, the flaky pigment of the present invention can be used as a pigment added to coatings applied to various materials such as paper, wood plates, metal plates, cloth, leather and plastics and to a composition such as printing ink containing resin.

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13
Examples
Hereinafter, the present invention is described in more detail by reference to the Examples, Comparative Examples and Test Example, which however are not intended to limit the present invention. Example 1
An aqueous solution containing 5.68 g sodium
hypophosphite (NaH2PO2H2O) was gradually added to 3 weight-% aqueous solution containing 5.76 g zirconium oxychloride
(ZrOCl2-8H2O) under stirring at room temperature so as not to cause white precipitates, to prepare a transparent aqueous solution. Then, 6 .0 g of 35 to 37 % aqueous hydrochloric acid solution was added to it to prepare a mixed solution of zirconium oxychloride and sodium hypophosphite.
Separately, 100 g rutile titanium oxide-coated mica titanium flakes (IRIODIN225 Rutile Blue, a product of E. Merck)
having a particle size of 10 to 60 \m exhibiting a blue reflection color and a yellow transmission color was suspended
in 1000 ml water, and the temperature was raised to 75 °C under stirring- The suspension was adjusted to pH 3 with hydrochloric acid, and 1.14 g of 10 weightr% aqueous cerium chloride (CeCl3-7H2O) was added thereto, and said mixed solution of zirconium oxychloride and sodium hypophosphite was added dropwise thereto for about 1 hour, during which the suspension was kept at pH 3 with 32 weight-% aqueous NaOH solution. After

WO 02/064682 PCT/EP01/01682
14
the whole mixed solution was added dropwise thereto, the
mixture was stirred at 75 °C for 30 minutes, then 2 g y-methacryloxypropyl trimethoxysilane (CH2=C(CH3)COO(CH2)3Si{OCH3)3 (Toray Dow Corning Ltd./SZ6030)
was added thereto, and the mixture was stirred at 75 °C for 15 minutes and its pH was raised to 7.0 with NaOH. 10 weight-% aqueous solution of 10.00 g af. perfluoroalkyl phosphate (CF3 (CF2) 7CH2CH2O) 2PO [ ONH2 (CH2CH2OH) 2 ] (UNIDIN TGI 01, Daikin Industries, Ltd.) was added dropwise to the suspension for
about 1 hour, and the mixture was stirred at 75 °C for 30 minutes . The resulting solid product in the suspension was filtered,
washed with water and dried at 13 0 °C.
A pearlescent pigment excellent in dispersibility with powder exhibiting a blue reflection color and a yellow transmission color was obtained in the procedure described above. When this pigment was suspended in a low polar organic solvent such as toluene and xylene, the pigment particles floated on the surface of the solvent and were orientated densely, whereupon a designing ability excellent in brightness with the outstanding reflection color of the pearlescent pigment was confirmed. Example 2
Using 100 g of the same rutile titanium oxide-coated mica titanium flakes (IRIODIN 225 Rutile Blue, a product of E. Merck) having a particle size of 10 to 60 nm exhibiting a blue

WO 02/064682 PCT/EP01/1H682
15
reflection color and a yellow transmission color as in Example 1, the same procedure using the same amounts of the same materials as in Example 1 was conducted except that the perfluoroalkyl phosphate was replaced by 2 g perfluoroalkyl silane CFjtCFjMCHjJjSifOCHjCH,), (Toray Dow Corning Ltd./AY43-158E).
A pearlescent pigment excellent in dispersibility with powder exhibiting a blue reflection color and a yellow transmission color was obtained in the procedure described above. When this pigment was suspended in a low polar organic solvent such as toluene and xylene, the pigment particles floated on the surface of the solvent and were orientated densely, whereupon a designing ability excellent in brightness with the outstanding reflection color of the pearlescent pigment was confirmed. Example 3
An aqueous solution containing 5.68 g sodium hypophosphite {NaH2PO:-H3O) was gradually added to 3 weight-% aqueous solution containing 5.76 g zirconium oxychloride
(ZrOClj-8H2O) under stirring at room temperature so as not to cause white precipitates, to prepare a transparent aqueous solution. Then, 6.0 g of 35 to 37 % aqueous hydrochloric acid solution was added to it to prepare a mixed solution of zirconium oxychloride and sodium hypophosphite.
Separately, 100 g iron oxide-coated mica flakes (IRIODIN

WO 02/064682 PCT7EP01/01682
16
504 Red, a product of E. Merck) having a particle size of 10 to 60 fxm exhibiting a wine red reflection color was suspended in 1000 ml water, and the temperature was raised to 75 °C under stirring. The suspension was adjusted to pH 3 with hydrochloric acid, and said mixed solution of zirconium oxychloride and sodium hypophosphite was added dropwise thereto for about 1 hour, during which the suspension was kept at pH 3 with 32 weight-% aqueous NaOH solution. After the whole mixed solution was added dropwise thereto, the mixture was
stirred at 75 °C for 30 minutes, then 2 g y-niethacryloxypropyl trimethoxysilane (Toray Dow Corning Ltd./SZ6030) was added
thereto, and the mixture was stirred at 75 °C for 15 minutes and its pH was raised to 7.0 with NaOH. 10 weight-% aqueous solution of 5-00 g of perfluoroalkyl phosphate (UNIDIN TG101, Daikin Industries, Ltd.) was added dropwise to the suspension
for about 1 hour, and the mixture was stirred at 75 °C for 30 minutes. The resulting solid product in the suspension was
filtered, washed with water and dried at 130 °C.
A pearlescent pigment excellent in dispersibility with powder exhibiting a wine red reflection color was obtained in the procedure described above. when this pigment was suspended in a low polar organic solvent such as toluene and xylene, the pigment particles floated on the surface of the solvent and were orientated densely, whereupon a designing ability excellent in brightness with the outstanding

WO 02/064682 I>CT/EP" 1/01682
17
reflection color of the pearlescent pigment was confirmed. Comparative Examples Comparative Example 1
Using 100 g of the same rutile titanium oxide-coated mica titanium flakes (IRIODIN 225 Rutile Blue, a product of E. Merck) having a particle size of 10 to 60 ^m exhibiting a blue reflection color and a yellow transmission color as in Example 1/ a pigment was obtained in the same manner using the same amounts of the same materials as in Example 1 except that the perfluoroalkyl phosphate was not used. Comparative Example 2
Using 100 g of the same rutile titanium oxide-coated mica titanium flakes (IRIODIN 225 Rutile Blue, a product of E. Merck) having a particle size of 10 to 60 ^m exhibiting a blue reflection color and a yellow transmission color as in Example 1, a pigment was obtained in the same manner using the same amounts of the same materials as in Example 1 except that the y-methacryloxypropyl trimethoxysilane was not used. Comparative Example 3
Using 100 g of the same iron oxide-coated mica flakes (IRIODIN 504 Red, a product of E. Merck) having a particle size of 10 to 60 ^m exhibiting a wine red reflection color as in Example 3, a pigment was obtained in the same manner using the same amounts of the same materials as in Example 3 except that the perfluoroalkyl phosphate was not used.

WO 02/064682 PCT/EP01/01682
18
Comparative Example 4
Using 100 g of the same iron oxide-coated mica flakes (IRIODIN 504 Red, a product of E. Merck) having a particle size of 10 to 60 jim exhibiting a wine red reflection color as in Example 3, a pigment was obtained in the same manner using the same amounts of the same materials as in Example 3 except that the Y-methacryloxypropyl trimethoxysilane was not used. Test Examples
The pigments obtained in the Examples and the Comparative Examples were examined in each of the following tests using test methods described below. The results of each test are collectively shown in Table 1. 1) Water resistance test (hot-water immersion test)
A thermosetting acrylic melamine resin (a mixture of Acrydic 47-712 and Super Beccamin G821-60 at a ratio of 7 : 3 by weight, Dainippon Ink and Chemicals, Inc.) was mixed at a concentration of 10 % by weight was applied at a dry film thickness of about 15 ^m on a zinc phosphate-treated steel plate (7 cmxl5 cm) having been coated with black enamel at a dry film thickness of about 20 \m and baked at 160 °C for 20 minutes, and the plate was left for 5 minutes and coated by air spraying with 7 weight-% dispersion of the resulting pigment in xylene,
left for 10 minutes and cured by heating at 140 °C for 30 minutes. The cured coated face was coated with a top clear coating of a thermosetting acrylic melamine resin (a mixture of Acrydic

WO 02/064682 PCT/EP01/0I682
19
47-179 and Super Beccamin L117-60 at a ratio of 7 : 3 by weight, Dainippon Ink and Chemicals, Inc.) at a dry film thickness of about 30 mn, left for 10 minutes and cured by heating at 140 °c for 30 minutes.
The test plate produced in the method described above was
immersed in hot water at 80 °C and kept therein for 8 hours, and then the temperature of hot water was decreased to room temperature, and the test plate was removed and visually checked to examine the change of its appearance.
Numerical values in Table 1 indicate that whitening/shrinkage performance is" inferior in the order of from 1C to 1.
2) Adhesion
The coated face of the test plate prepared in the water resistance test was cut such that the cut reached the base
material whereby 100 cut-line squares with a size of 1 mmxl mm were made thereon, and a cellophane tape was attached to the surface and rapidly peeled off, and then the coated face was observed.
O indicates that 9 or less squares were removed, and x indicates that 10 or more squares were removed.
3) Hue measurement (chromatic value)
C-value (chromatic value) was measured at an angle of
incidence of 25° and at a light-receiving angle of 20° with a varied-angle color measurement meter GCMS3 (Murakami Shikisai

WO 02/064682

20

PCT/EP01/01682

Co., Ltd.)- The C value is indica the intensity of
reflection color of the pearlescent pigment, and a large C value
indicates stronger color. This is correlated with the
denseness of particles due to the leafing effects of the
pigment.
4) Designing ability
The coating was visually evaluated. In Table 1, O indicates a designing ability excellent in plating-like
brightness, and x indicates the designing ability of a usual pearlescent pigment. Table 1

Test Sample Amount of Group (A) Used Amount of Group (B) Used Water Resistance
Test Whitening/ shrinkaqe Adhesion Hue Measurement C value Designing Ability
Example 1 10 weiqht-% 2 weiqht-% 6/7 0 80.1 0
Example 2 2 weiqht-% 2 weiqht-% 6/7 0 84.1 0
Example 3 S weiqht-% 2 weiqht-% 6/7 0 80.6 o
Comparative Example 1 ^^ 2 weight-% 6/7 0 68.0 X
Comparative Examole2 1Oweight-% ^^ SJ6 X 80.2 0
Comparative
Example 3 ^^ 2 weight-% 6/7 0 62.3 X
Comparative
Example 4 5 weight-% 5/6 X 79.8 0
1) Group (A) indicates the amount of the organic compound having a perfluoroalk yl group in the
Examples and Comparative Examples
2) Group (8) indicates the amount of the coupling agent in the Examples and Comparative Examples
Industrial Applicability
It was found in the present invention that a novel flaky pigment having the leafing effects of flaky pigment particles on a coating and being excellent in the interlaminar adhesion

WO 02/064682 PCT/EP01/01682
21
between flaky pigment particles and a coated film is obtained by coating the surface of a flaky pigment with a combination of a coupling agent and an organic compound having a perfluoroalkyl group. By having such properties, the flaky pigment particles are orientated densely on the coating, thus reinforcing plating-like brightness and effectively exhibiting the pearlescence of particularly a pearlescent pigment. Further, the effect of improving the interlaminar adhesion prevents the exfoliation of a clear coating thereby achieving lasting brightness and improving the durability of a coating or printing ink.

-22-
1. A flaky pigment for resin composition, which Is coated with a coupling agent and
an organic compound such as herein described haying a perfluoroalkyl group on
the surface of the flaky pigment.
2. The flaky pigment for rasin composition according to claim 1, wherein the flaky
pigment is one or more members selected from peariescent pigments and metal
pigments such as herein described.
3. The flaky pigment for resin composition according to claim 1 or 2, wherein the
flaky pigment is a pigment in which hydrous zirconium oxide formed by hydrolysis
of a zirconium compound in ihe presence of hypophosphite, and/or a hydrous
compound formed by hydrolysis of one or more wafer-soluble compounds of
metal selected from cobalt, manganese and cerium has been deposited on the
surface of a peariescent pigment.
4. The flaky pigment for resin composition according to any one of claims 1 to 3,
wherein the organic compound having a perfluoroalkyi group is one or more
members selected from compounds represented by the general formulae (I) to
(IID below:
phosphetes having a perfluoroelkyl group, represented by the general formula (I):
[Rf(CnH2nO)tTJ,PO(O?^)3.y (I)
wherein Rf represents a straight-chain or branched Cg to C21 perfluoroafkyl group
or perfluoroalkyloxy group, M represents hydrogen, an alkali metal, ammonium
and substituted ammonium,

WO 02/064682 PCT/EPO1/O16S2
23
n is from 1 to 4, m is from 0 to 10, and y is from 1 to 3; phosphates having a perfluoroalkyl group, represented by the general formula {II):
(Rf SO2NRCnH2nO) ,PO (OM) 3_y (II)
wherein Rf represents a straight-chain or branched Cfi to c31 perfluoroalkyl group or perfluoroalkyloxy group, M represents hydrogen, an alkali metal, ammonium or substituted ammonium, R represents hydrogen or a Ct to C3 alkyl group, n is from 1 to 4, m is from 0 to 10, and y is from 1 to 3; and perfluoroalkyl silane represented by the general formula (III):
Rf(CH2)nSiX3 (III)
wherein Rf represents a straight-chain or branched Cx to c12 perfluoroalkyl group, X may be the same or different and represents an alkoxy group, a halogen group or an alkyl group, provided that not all X groups should be alkyl groups, and n is from 1 to 5.
5. The flaky pigment for resin composition according
to any one of claims 1 to 4, wherein the coupling agent is one
or more members selected from a silane coupling agent, a
titanium-based coupling agent and a zirconium-based coupling
agent.
6. The flaky pigment for resin composition according
to any one of claims 1 to 5, wherein the coverage amount of
each of the coupling agent and the compounds represented by

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24

PCT/EP01/0J682

the general formulae (I) to (III) is 0.05 to 20 % by weight relative to the flaky pigment.
A flaky pigment for resin composition, which is coated with a coupling agent and an organic compound such as herein described having a perfluoroalkyl group on the surface of the flaky pigment.

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Patent Number

201127

Indian Patent Application Number

01150/KOLNP/2003

PG Journal Number

08/2007

Publication Date

23-Feb-2007

Grant Date

23-Feb-2007

Date of Filing

09-Sep-2003

Name of Patentee

MERCK PATENT GMBH

Applicant Address

FRANKFURTER STRASSE 250, 64293 DARMSTADT, GERMANY

Inventors:

#	Inventor's Name	Inventor's Address
1	EIJI UMEHARA	51-15 AZA EGOSHI, KUROSUNO, IZUMI-MACHI, IWAKI-SHI FUKUSHIMA-KEN JP
2	KOUSHIRO KUNII	51-15 AZA EGOSHI, KUROSUNO, IZUMI-MACHI, IWAKI-SHI FUKUSHIMA-KEN JP

PCT International Classification Number

C09C 1/00

PCT International Application Number

PCT/EP01/01682

PCT International Filing date

2001-02-15

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA