C.I.颜料红31的亲水化改性及其在水性油墨中的应用性能研究

Hydrophilic Modification of C.I.Pigment Red 31 and Its Application in Water-based Ink

为提升C.I.颜料红31的亲水性,使之更加适用于水性油墨,在颜料生产的偶合过程中选用2-羟基-3-萘甲酰基-(4′-氯-2′,5′-双甲氧基)苯胺(色酚AS-LC)参与2-羟基-3-萘甲酰基间硝基苯胺(色酚AS-BS)偶合剂的制备,并与3-氨基-4-甲氧基-苯甲酰苯胺(红色基KD)的重氮产物进行偶合反应,制得水性C.I.颜料红31。接触角、SEM、色光、热重分析结果表明,经过色酚AS-LC改性的颜料样品晶体形貌可由长条状转呈圆片状,其用量为5%(mol)时,可使颜料与水之间的接触角降至53.4°,粒径及粒径分布明显变窄,具有最佳的亲水性能。色酚AS-LC与色酚AS-BS的共偶合会使颜料色样偏向红色和蓝色,但色差(ΔE)较小,值为0.52。氮气氛中加热至270℃颜料晶体开始分解,达到了耐高温颜料的标准。制备成水性油墨并测试其易分散性、流变性能及相关印刷适性,结果显示均明显优于未经水性化改性的C.I.颜料红31。

In order to improve the hydrophilicity of C. I. pigment red 31 and make it more suitable for water-based ink, 2 hydroxy-g-naphthoyl-（4＇-chlorine-2＇, 5＇-dimethoxy） aniline （naphthol AS-LC） was selected to participate in the coupling agent preparation of 2-hydroxy-3-naphthoyl m-nitroaniline （naphthol AS-BS）, and then carry out the coupling reaction with the diazonium salt 3-amino-4-methoxy benzoyl aniline （red base KD）. Thus the hydrophilic C. I. pigment red 31 was obtained. The contact angle, GEM, color capability and thermogravimetric analysis show that the crystal morphology of the pigment modified by naphthol AS-LC can be changed from long strip to disk shape. When the dosage is 5% （mol）, the contact angle between pigment and water can be reduced to 53.4%, the pigment particle size and particle size distribution narrow down, the hydrophilic property can he best. The coupling of naphthol AS-LC and naphthol AS-BS results the pigment hues convert into red and blue to some extent, and the color difference （AE） is small, with a value of 0.52. The pigment crystal begins to decompose when it is heated to 270℃ in nitrogen, it is obvious that the pigment has reached the standard of high temperature resistant pigment. Compared with traditional pigment, The dispersity, rheologicaI properties and other printability of the pigment prepared by this method are obviously better.