It’s well known that pigments are not dissolved both in water and solvents, so they are dispersed by dispersants in plastics which exhibits opaque mostly, organic pigments and fluorescent pigments are hard to disperse and tend to form agglomerates, which will cause spots and specks in finished products, inorganic pigments are more easily dispersed. Solvent dyes can be dissolved in polymers which show transparent. Colorants applied in plastics require stable physical and chemical characteristics, brilliant undertone, high color saturation, strong color strength, good dispersibility and migration, heat resistance according to different materials will be different, PP, PE and PVC are low heat resistance, while engineering plastics require high temperature resistance. Plastics’ main moldings include extrusion molding, injection molding, calendaring molding, foam molding for polyethylene foaming and polyurethane foaming, membrane blowing, fiber drawing etc. There are thermoplastic and thermosetting plastics by their characteristics. PE, PP, PVC including soft PVC and rigid PVC / PVC-U, PS, PA, POM, PC and PMMA etc. are thermoplastics, while bakelite /phenolic molding compound, amino plastic, epoxy plastic, organic silicon plastic and polysiloxane plastic etc. are thermosetting plastics. All of these plastics are widely used in synthetic leather, home appliance, automobile part, mechanical part, cable, insulating plate, electrical part, plastic building material, door and window PVC profile, vinyl covering, gutter, roof profile, sheet, hose, belt, matting, water supply and drainage pipe, PVC pipe, film bag, wrapping film, foamed plastic, plastic pack /container, office stationery, loudspeaker, labeling, glove, toy, flip-flop, flooring, lamination, pad, tube, tire for baby carriage and plastic wrap, road traffic infrastructure, vehicle part, clothing fiber, rope, thermal underwear, fishing net, carpet and lawn etc. Among all the plastics, fiber including filament fiber and staple fiber has a high requirement for pigments, which needs to own excellent dispersion, very low PFV (Pressure Filtration Value) and high tinting strength which can make sure the pigment working well in fibers. Polyurethane artificial leather is a sort of PU elastomer, it is glossy, natural, soft, anti-abrasion, anti-flexure, anti-aging, cold tolerance and breathable, washable, easy-manufactured and low cost, PU artificial leather has become an ideal substitute for natural leather and has been widely used for clothing, shoe sole, bag, and furniture applications. With more and more colors demanding, pigment dispersion / paste is using in emulsion and synthetic latex, such as balloon, household glove, fireproof board / HPL/ decorative high-pressure laminate etc.. You can find all the details of colorants for plastic, master batch and leather here.