Pigment Red 254 belongs to pyrrolopyrrolodione pigments, which have excellent high temperature resistance, strong light fastness and high color saturation

254 red has excellent temperature resistance, such as domestic KP red, SR20 of Xiannico Chemical, which can withstand a temperature of 250 degrees, and Clariant's D3G can withstand a temperature of 270 degreesCiba 2030 can withstand a temperature of 280 degrees, and some modified products can be heated and stabilized above 300 degrees, and its products were patented by Iqbal et al. as early as 1983, proposing a method for synthesizing pigments from disuccinate diesters. In 1986, CGY company realized the industrial production of DPP pigments, which have the characteristics of bright color, high color saturation, high tinting strength, high hiding power, excellent weather resistance and ultraviolet resistance, good fluidity, easy dispersion, and strong resistance to acid and alkali erosion; Due to the existence of intermolecular hydrogen bonds, it has solvent resistance that is completely absent such as 170 and 3132 large red, and has stable migration resistance and heat resistance, which is suitable for automotive paints, composite materials, high-concentration colorant preparation, and coloring of 3C electronic industry coatings.

 Effect of the structural properties of pigment red 254 on the preparation of color paste

The molecule has good symmetry, the position of each atom in the molecule is arranged in a plane, and there are intermolecular hydrogen bonds, forming a three-dimensional stacking, so that it has excellent fastness performance, and each molecule is connected by three forces, namely hydrogen bonding force, van der Waals force and hydrogen bonding force between adjacent molecules; A chain is formed in the diagonal direction. There is an intermolecular force between the phenyl atoms at the end of each molecular chain of the same molecule, which forms a large molecular layer plane, and under the action of three forces, the crystal is tightly combined, and the molecular arrangement is a three-dimensional network structure. The protruding surface of this structure in 254 pigment has a fairly high melting point, low solubility and resistance to UV damage. According to the requirements of the composite materials for the ultra-long anti-aging of pigments, Thyssen's high-performance unsaturated polyester color paste UP826 adopts the electrophilic and nucleophilic substitution reaction on the benzene ring, and the N-alkylation and N-acylation reaction occur on the imide nitrogen atom, which improves the compatibility with the resin, and provides help for the more homogeneous dispersion state of the pigment in the resin, under the premise of stable temperature resistance of 280 degrees. The saturation of the color is greatly increased to improve the color vividness of the pultruded profile. However, the ability to form hydrogen is eliminated by the dialkyl halide on pyrrole cyclonitrogen, and the ability to bond hydrogen between molecules is no longer available, which can improve transparency. With its friendliness to pigments, 254 red does not contain heavy metals such as lead, chromium, mercury, chromium, etc., and is harmless to the human body in the finished product, and is also widely used in export toy products, and has become popular for Lego products in recent years