Pigment purple, the pigment product dosage forms have 128 kinds of grades. For high-grade industrial coatings, with inorganic pigments such as iron oxide red, transparent type can be used for metal decorative paint; can also be used for plastic such as PVC and PUR coloring.
Pigment purple product dosage forms have 128 kinds. For high-grade industrial coatings, with inorganic pigments such as iron oxide red, transparent type can be used for metal decorative paint; can also be used for plastic such as PVC and PUR coloring, art pigment ink, high temperature organic pigments, halogen-free organic pigments, halogen-free toner. Pigment purple is mainly used for leather paint, high-grade plastic resin, paint printing, soft plastic products, synthetic fiber coloring. Heat 300-450 light resistance 8, resistant to migration 5, pure color full, strong coloring, good color fastness , Excellent solvent resistance, excellent thermal stability, resistance to high temperature of 300 degrees, excellent weather resistance, with high resistance to light fastness, good dispersion, easy to modulation, Pigment Violet easy to use, as a color paint can be modulated out A variety of colors, safe and environmentally friendly. Scope of application:
Ink: for lithography, table printed NC / PA, wrapped CL-PP, resistant to cooking, printing iron, water-based ink Features: transparent, fastness
Paint: Apply to paint, dry, car OEM, car repair, toy paint, industrial paint, Pigment Violet powder coating, coil, architectural coatings Features: high transparency, high concentration, easy to disperse
Plastic: for PVC, LDPE, PPHDPE, PU, ABS, PPFiber, nylon 66, rubber, etc.
Printing and dyeing: paint printing characteristics of bright color paste, strong coloring. Excellent light fastness, acid, alkali, no migration,
Preparation of easily dispersible pigment violet
FIELD OF THE INVENTION  The present disclosure relates to pigment compositions suitable for use in blue pixel portions of color filters. In addition, the present disclosure relates to a process for preparing a modified dioxazine pigment having improved dispersibility in an aqueous system and dispersion stability over time. The present disclosure also relates to a color filter pigment produced from a modified pigment, and a liquid crystal display device comprising the same.
BACKGROUND OF THE INVENTION Color filters are widely used to display colors, such as a liquid crystal device (LCD), which consists of three color pixels (red, green, and blue) arranged in a color matrix pattern. Methods for preparing color filters are known in the art, such as dyeing, printing, electrophoretic deposition, Pigment Violet and pigment dispersion. In particular, the pigment dispersion method is widely used in which a composition for a color filter is obtained by dispersing a pigment with a photosensitive polymer and / or a monomer. The micropores are formed by a photolithography method, whereby excellent light does not fade, heat resistance, and solvent resistance. The pigment should have a characteristic of clearly displaying an image (high contrast ratio) on the IXD board and displaying a bright image (high brightness). In addition, it should maintain important color characteristics such as hue, color intensity, Pigment Violet gloss and transparency. Hue should match a very specific color index. In the case of multi-color printing and dyeing, the color palette should be wide enough to provide the maximum number of tones. In view of this, there is a need for a pigment which can be used in a color filter which has excellent performance in terms of color, strength, color and transparency, and at the same time can achieve high Contrast ratio and high brightness. Pigments used in the pigment dispersion process may be selected from those pigments which are generally known in the art and, if desired, at least two pigments may be mixed to have the desired transmission characteristics. For example, in many cases, a pigment is prepared by using Pigment Blue 15: 6 (a blue pigment comprising a copper phthalocyanine dye), together with Pigment Violet 23 (a pigment violet containing carbazole dioxazine) Color photoresist ink in blue pixels. The pigment violet 23 has a blue transmissive zone moving to shorter wavelengths than the phthalocyanine dye. Thus, it is widely used to improve the color purity of blue pigments including copper phthalocyanine, which lightly transmits green light. The color purity can be defined as the absence of an undesired color in the dot produced by each RGB pigment on the screen by the color filter. Pigment Violet Polycyclic and heterocyclic pigments have many common properties due to their planar chromophore structures, which are almost insoluble, even at high processing temperatures, and exhibit very good color fastness Features, including excellent stability for light, climate and heat. On the other hand, they exhibit poor dispersibility and the rheology of the compositions that include them still remains to be improved. The pigments obtained after the synthesis or final treatment are not suitable for direct use in many cases. Pigment Violet This often leads to problems such as incomplete dispersion and flocculation. This results in a lack of color strength and fine precision in the pigment. Not adequately dispersed pigments may also be tricky during further processing. In particular, this leads to a settling problem in a low viscosity system. In addition, flocculation, storage or further processing in the dispersion process can not be eliminated, resulting in rheological modification of the undesired system and resulting in loss of surface defects, color strength and gloss of the applied film. In order to improve the nature of the pigment in practice, it is advantageous to modify the surface of the pigment by incorporating the polar functional group into the pigment product. This results in a significant improvement in quality as compared to the corresponding unmodified base pigments. In this regard, a number of proposals have been made for influencing the rheological properties of pigments. However, the prior art has not been able to satisfactorily address the problems of rheology, Pigment Violet dispersibility, flocculation, pan, gloss and color strength. U.S. Patent No. 5,271,759 discloses a pigment composition comprising an organic pigment having a plurality of chromophores, a sulfonated pigment derivative, and a polymeric quaternary ammonium salt. These pigment compositions are said to have good rheology in the surface coating and the printing ink, which makes it possible to carry out warpage without polyolefin. U.S. Patent No. 5,275,653 discloses a pigment article comprising a dioxazine pigment (Pigment Violet 23) and a sulfonated dioxazine derivative as a dispersant. Which illustrate that these pigment products have improved rheology and color characteristics. There are also a number of published reference documents in the art which disclose a variety of functional groups, such as dioxazine derivatives having sulfonic acid groups (U.S. Patent No. 4,400,504 and European Patent Publication (Japanese Patent Laid-Open No. Hei 6-228454); a sulfonated pigment having an ammonium salt (U.S. Patent No. Hei 6-228454); a sulfonated pigment having a sulfonamide group (-SO2-NH (CH2) N) Patent Nos. 6,827,774 and 6,827,775); a pigment having a carboxysulfonamide group (U.S. Patent No. 6,918,958); a sulfon having a sulfonate and / or heteroaryl group Of the pigment (U.S. Patent No. 7,077,898). Also disclosed is a method of treating the surface of pigment particles. U.S. Patent No. 5,928,419 discloses a surface-treated organic pigment which has excellent initial dispersibility in water and an organic solvent and has long-term dispersion stability without the coagulation of pigment particles. Such organic pigments are obtained by mixing a sulfonating agent (selected from sulfamic acid or pyridine sulfur trioxide complex) with a solvent which is dispersed in a solvent in which the organic pigment is insoluble or slightly soluble Of the organic pigments in the reaction. Thus, the sulfonic acid groups are introduced onto the surface of each particle of the organic pigment. PCT International Publication No. WO 06011338 discloses a pigment dispersion composition which exhibits good flowability and dispersion stability (even when the pigment concentration is high), wherein the pigment dispersion is prepared by mixing a pigment Dispersed in a dispersion medium. The surface of the pigment is coated with an acid group-containing reaction product by reacting a carbodiimide compound having at least a carbodiimide group with an acid group-containing resin And obtained. In the preparation of a pigment violet dispersion, Pigment Violet since the pigment itself has a lower solubility in the solvent, a grinding machine (which uses particles and other materials in the presence of a grinding medium such as glass spheres) Grinding) or a dispersing machine in which the particles are uniformly dispersed by shearing forces. For example, U.S. Patent No. 6,451,103 and International Publication WO 05054381 disclose a process for the preparation of a pigment dispersion in which a dispersing machine such as a ball mill, a sand mill, an air jet mill, a hammer mill or the like is used. These machines differ from the kneading apparatus in that they use a grinding medium for the production of the dispersion. Among other things, a valuable pigment violet must exhibit high and easy dispersibility, rheology, and color characteristics, as well as flocculation stability. However, dioxazine pigments (like pigment violet 2 lack some of these properties).