1, food colorants: food coloring to the primary purpose of a food additive known as a colorant, also called pigment. 2, by source: food can be divided into synthetic coloring agents and natural food colorants two categories. 3, according to the structure: synthetic food coloring agents can be divided into azo colorants and non-azo colorants; 4, food and natural colorants can be divided into azoles, polyenes, ketones, quinones and polyphenols class. 5, according to the solubility of the colorant point: can be divided into fat-soluble and water-soluble. In addition to fertilizer manufacturers colorant, the toner due to the manufacturer's production date, lot number of different fertilizer colorants, the same brand of toner there are a certain color, even if you insist on using the same formula fertilizer colorants companies, but in the process the process is very difficult to injection product batch to batch color consistency, while masterbatch in the production process by way of sampling, testing, adjusting to compensate for each batch of toner color, contrast, color masterbatch for color reproducibility was better than toner. Quality fertilizer colorant, Weifang Fuyuan (certified), fertilizer colorants provided by Environmental Science and Technology Co., Ltd. Weifang Fuyuan. Weifang Fuyuan Environmental Technology Limited (www.wfdafuyuan.com) (www.wfdafuyuan.com) Shandong Weifang, other leaders, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer demand. In Weifang Fuyuan leadership with the staff warmly welcome all inquiries negotiations to create Weifang Fuyuan better future.