Synthesis, Modification And Application Properties Of Nature-Identical Naphthoquinone Colours

Faced with the "green barriers" in international trade, "low-carbon economy" and "clean production" are becoming more and more imperative. For Xinjiang, one of the most important textile industry bases in China, it is urged to develop environment-friendly technology and products in native dyeing and finishing industry. According to the research tendency and our previous study, 1,4-naphthoquinone, which has excellent UV protection performance, was chosen as our research direction. In the paper, the relationship between the structure of natural colour (dyes) and wool dyeing properties or UV protection performance was established; new environmentally efficient methods to prepare nature-identical naphthoquinone or naphthoquinone derivatives were developed; with the structural modifications of synthetic naphthoquinone or naphthoquinone derivatives, excellent dyeing properties and UV protection performance were achieved.In chapter two, raw materials, extracting agents, and the dyeing properties of colours extracted were studied. Arnebia euchroma and lawsonia inermis in Xinjing were chosen as raw materials and natural colours were extracted by solvent with high efficiency and low toxicity. Dyeing performance and solubility of colours could be improved by mild sulfonation method. By means of general rotation experiments, the optimistic dyeing processes of lawsone and sulfonated shikonin were established. Dyeing performances of dyes and the mordant dyeing properties with environment-friendly mordants were studied.In chapter three, we studied the synthesis of naphthoquinone colours. Six naphthoquinone colours and derivatives were rynthesized using safe and inexnensive reactants Effective svnthetic route was designed to make the naphthoquinone have one or more hydroxyls (-OH group). With different raw materials and synthetic methods, the groups such as -CH3,-OCH3 or -Cl were introduced to naphthoquinone, which was the preparation of structural modification.In chapter four, the synthesis of non-azo naphthoquinone colours and their mordant dyeing performances were studied. Based on the study of building conjugated systems through carbon-carbon double bonds, two types of naphthoquinone colours were designed and synthesized. The effective methods to enrich colour chromatography and to improve dyeing properties were developed. Through the design and synthesis of the amount and location of hydroxyl on naphthoquinone, the mordant dyeing performances were improved.In chapter five, the UV protection performances of colours were studied. UV protection properties of lawsone and shikonin extracted, sulfonated shikonin, synthetic naphthoquinone and naphthoquinone derivatives treated through structural modification were studied. The preliminary interpretation of UV protection properties was carried out using fluorescence spectroscopy The results showed that four kinds of methods to extract lawsone and shikonin these had some disadvantages such as cumbersome process, hardly controlled purity and low product yield. So it was uneconomic and unrealistic to dye wool fabrics with natural naphthoquinone derivatives. It was found that extracted lawsone and sulfonated shikonin, synthetic naphthoquinone and naphthoquinone derivatives could be used in dying wool fabrics, and the deep-dyeing, chromatic properties and color fastness were affected by some factors such as extracting methods, pigment types and parameters of dyeing process. environment-friendly mordant such as Al3+, Mg2+, Fe3+ and Fe2+ could differently enhance the mordant dyeing performances of naphthoquinone extracted or synthesized on wool fabrics.It was also found that natural naphthoquinone colours and their sulfonation had some UV protection properties. The synthesized 5-hydroxy-8-methyl-1,4-naphthoquinone and 5,8-dihydroxy-1,4-naphthoquinone had excellent UV protection performance and synthesized tetrone colours had more. By measuring fluorescence spectroscopy, it was found that these cholurs could be excited by UV and generated fluorescence between 395 to 500 nm, which was worth further studying.Innovations:(1) Innovation in research idea:In the paper, the native natural sources such as arnebia euchroma and lawsonia inermis and wool fibers, which are widely existed in Xinjiang, were chosen as study objects. The dyeing properties and UV protection performance of natural naphthoquinone were studied. The colours (dyes) which had the same structure with natural naphthoquinone were synthesized. Based on the morden concept of molecular design, synthetic naphthoquinone or naphthoquinone derivatives were modified. According to ecological standards of textiles and the need of UV protection, the new method of UV protection was developed by synthesizing dyes which had the properties of UV protection.(2) Innovation in the method of synthesis: On the basis of total synthesis of 6-chloro-5-hydroxy-1,4-naphthoquinone, a new method to synthesize hydroxy naphthoquinone derivatives was established. In the method, safe and inexpensive glycerol was used as starting materials. At the same time, mixed solvent and environment-friendly catalysts were used. The method had the some advantages such as cheaper raw materials, simple synthetic process, convenient separation and purification process and high product yield. An important compound 3-hydroxy-4-chloro-2-pyrone was also synthesized. Two patents were applied for and patent application numbers were 201010617028.1 and 201010617005.0, which were all in substantive examination phase. In addition, a method to synthesize 5.8-dihvdroxy-1,4-naphthoquinone using (?) acid was established and the (?) of the (?) of tetronc colours with 2-hydroxy-1,4-naphthoquinone was improved.(3) Innovation in applied technology: The method that increasing solubility of shikonin by-additives was applied to the dyeing. It was found that self-made solubilizing agent WP could improve the solubility of shikonin and the apparent dyeing depth and the brightness on wool fabrics. Mild sulfonation approach was used to enhance the solubility of shikonin extracted and naphthoquinone colours synthesized, which enable their good using in direct dyeing and mordant dyeing.