Unfamiliar and familiar dye plants

Red dye plant

  If every country has a color that represents its own national preferences, personality and cultural characteristics, then “red” must be one of China’s “national colors”.
  Madder
  Ancient Chinese have long know how to use certain plants to obtain different levels of red. Among them, madder should be the first red dye plant to enter human life. The so-called “madder color” is the color extracted from the roots of madder. In the large number of unearthed silk fabrics, madder dyeing accounts for a considerable proportion. For example, the deep red silk unearthed from the Mawangdui No. 1 Han Tomb in Changsha was dyed with madder.
  Madder has strong vitality, and it often appears in the mountains and forest wasteland in the posture of grass climbing vines, which is unforgettable. What is interesting is that the leaves of the genus Rubia often have 4 to 6 leaves in each section of the stem without obscuring each other. Picking up a long climbing stem, the arrangement of the leaves is very layered and quite regular. Botanist The arrangement in which more than two leaves grow on such a stem node at the same time is called “whirlpool”.
  Safflower
  contrast, the red safflower really closer to what we usually say “Red China” madder than Sin, the ancients also think the former is more pure red, saying it was really red. However, the production technology of true red lags behind that of madder for a long time, and its price is much higher than that of madder. Because extracting pure red from safflower is very complicated and more labor intensive.
  It turns out that safflower contains two kinds of pigments: red pigment and yellow pigment. Red pigment is safflower pigment. The content of dried safflower is very low, only about 0.5%, and the yellow pigment content is about 30%. Therefore, if you use safflower to produce high-purity true red, you have to find ways to remove the yellow pigment and other impurities. With such a low content of safflorin, it is no wonder that it was once as expensive as gold.
  How to remove the yellow pigment? Any successful technology is rooted in scientific knowledge. We should first grasp a scientific principle: Carthamin can be dissolved in alkaline solution, but not in acid and water; yellow pigment is soluble in water and acid, but not in alkali. It can be said that this principle gave birth to a series of application technologies such as the preparation, extraction, printing and dyeing of modern safflower dyes.
Yellow dye plant

  Many Chinese costume dramas use costumes to “tell us” that yellow was a “royal color” in ancient times, and ordinary people and even officials outside the royal family could not use it casually.
  Gardenia
  Gardenia is a cousin of madder, Rubiaceae Gardenia is a member of the genus. The fruit is green when the mast is just entering the fruiting period and turns yellow when it is ripe. Yellow saffron fruit contains terpenoid crocin and flavonoid saffron yellow pigment. Among them, crocin and crocetin can effectively dye wool fibers, while saffron yellow pigment is good for protein fibers such as wool and silk. Dyeing effect, and the pigment is easily soluble in water, which shows that the preparation process is relatively simple, we can reproduce the ancient “decocting method” at home: take fresh squash fruit, crush, soak in water for several hours, filter , You can get the yellow dye solution; or take the mature and dry jasmine fruit, soak it in cold water overnight, peel off or crush the fruit after it becomes soft, add fire to boil, filter to take the first dye solution; then fry Boil, filter, and repeat the dye solution 3 to 4 times. Finally, put the fabric directly into the dye solution, and you can harvest a healthy, environmentally friendly and pollution-free handmade product. In addition, we can use acidic substances and mordants to control the depth of “Manda Yellow”. For example, adding acetic acid can make “Manda Yellow” brighter, adding chromium mordant to get grayish yellow, and adding copper mordant to get bright yellow. , Add iron mordant to get dark yellow.
  Unfortunately, the color is easy to pick up, and it is easy to fade. The pigment of Mastiff is weak against sunlight, so the biggest defect of dyeing with Mastiff is that it cannot be “exposed”. It is most suitable for dyeing some indoor products, and can also be used as a primer for other dyes.
  SJ
  as Sophora japonica dye plants, is every inch a native species in northern China – Sophora japonica. It has a cousin relationship with Robinia pseudoacacia, and both belong to the legume family, but the Chinese locust is a member of the Sophora genus, and Robinia pseudoacacia is a member of the Robinia genus.
  The Chinese Sophora japonica has yellow and white flower clusters, fragrant and beautiful, and it is often used as street trees and excellent nectar plants. The part used to prepare the yellow dye is generally the buds that are ready to be placed, which are shaped like rice grains and are also called “Sophora rice”. The main pigments contained in Huami belong to mordant dyes, which require the addition of mordant to dye fabrics. Therefore, when making Sophora japonica dye, it is best to add a mordant to the soup. Generally, alum or green alum are used to effectively extract Sophora japonica pigment. When dyeing, different mordants can be used to dye various colors: tin mordant gives brilliant yellow, aluminum mordant gives straw yellow, and chromium mordant gives grey green. The boiled Sophora japonica dye is orange-yellow, which is similar in color to that of the jade, but it is more resistant to the sun. Therefore, after the yellowing technology of Sophora japonica, the “yellow” status of the jade is not as good as before. .
Blue dye plant

  Bluegrass
  ancient blue clothing is often worn to civilians, so the demand for blue dye is enormous. There are also many kinds of plants that can be used to extract blue dyes, which were collectively called blue grasses by the ancients, including the blue grasses of the small family, the isatis of the cruciferous family, the horse blue of the Acanthaceae family, and the sophora blue of the legume family.
  As far back as the Stone Age, when our ancestors rubbed the fresh blue grass leaves with their hands, they found that their hands were blue-green at first. After washing with water, they gradually turned into a long-lasting blue color, which inspired them to use fresh blue grass leaves. Rub-dyed textile fiber products. Later, people gradually transformed “rubbing” into “soaking”, mashing fresh blue grass leaves in a container, soaking in cold water to remove leaf residue, throwing fiber products into the container for soaking, and then taking it out to air dry and wash. To achieve a dark effect, dip dyeing can be repeated several times.
  Bluegrass leaf juice contains indigo glycosides, which is colorless, but it will be oxidized to indigo when it is contaminated with fabrics and exposed to air. Therefore, no matter whether the rubbing method or the dip dyeing method is used, the proper fresh leaves should be harvested. It is too early or too late. Late collection of fresh leaves is not conducive to dyeing. However, long-term labor practice can always give birth to brilliant wisdom. Dyeing workers finally noticed that after long-term storage of the waste bluegrass fresh leaf dye solution, the blue sediment at the bottom will be fermented, which will then have the effect of re-dying fibers. Soon, this observation and summary coupled with continuous experiments led to the gradual formation and rapid development of indigo production and natural fermentation dyeing technology, laying a solid foundation for the popularization of blue fabrics in the world after the Ming Dynasty.