Living in Xunzi for more than two hundred years ago, and the blue coarse tweed jeans occupied the global wardrobe, is there a relationship?

It is basically no relationship.

Since he didn’t have a relationship, is this title to engage in things? That’s right, I have an effort to arrange this title to lie to you. (Crazy)

Don’t go! In fact, Xunzi and jeans are not unreasonable, and a secret link is hidden in the famous sayings of “persuasion” – “Green, take it from blue and blue blue”.

“Qing” is not blue, “blue” is not blue

“Blue” in Xunzi is not “blue” we often say, but

A type of plants that extract blue dyes

. The dye extracted from such plants is the “blue” of Xunzi, also called



Indigo | Washing Wash

There are many plants in the world that can be used to extract indigo. Among them, there is a common bean plant wooden blue (

IndigoFera Tinctoria

), 蓼 科 蓼 蓼 (


Polygonum Tinctorium

), Juebei Plant Malay (


) And cruciferous plants

Lsatis Tinctoria



(Small knowledge: 菘 菘 is a treasure plant, but it can not only use the dye, but also cure the disease – its root is common Chinese medicine board blue roots, the leaves are another Chinese medicine big blue leaf.)

Wooden Blue Wikimedia Commons, Kurt Stüber / CC BY-SA 3.0 (


蓼 Blue Wikimedia Commons, UDO SCHRöTER / CC BY-SA 3.0 (


Ma Blue Wikimedia Commons, Rhododendrites / CC BY-SA 4.0 (

菘 Blue Wikimedia Commons, Pethan / CC BY-SA 3.0 (

Indigo has a long history in the world, and various plants have also divided their own “power range” worldwide. Mukan is suitable for growth in the tropics. It is the main raw material for India to extract indigo; in the temperate area, it is suitable to grow in the temperate area. , Medium temperature belt, cold temperate and plateau climate zone, therefore, we have chosen “all” in the production of indigo raw materials.

Wooden, Ma Blue, Blue and Blue and Blue are all raw materials for my country

In my country’s traditional manual staining technology, indigo plays a very important role. As early as Xia Dynasty, there was “May, from the Blue” in my country, “May, the Book of Songs” also has the sentence of “Final Lan”. This shows that our ancestors have already started planting blue, and they are very familiar with its growth habits.

In the Northern Wei, “Qi People wants” in this record –

“In July, it is a hundred bunch, making the wheat stalk mud, so that the depth is five inches, so that the four walls are all in the pit, and the water is not in the wood, and the wood stone is not. The accommodation, the cold, the juice, the juice in the middle of the juice. Rate Ten stone, the lime is five liters, acjection, one eat, clarify, lax water, don’t make a small pit, store Blue is in the pit. Waiting for a strong porridge, it is also in the middle, and the blue will become. “

This classical Chinese may look from the masses, give you a simple translation: in the middle of the lunar calendar, dig a pit on the ground, put the blue cut in the pit, add water, and then use the weight, let the water do not Blue. In this way, the residue is removed, and the obtained juice is stirred with a certain proportion of lime water, and finally the paste of the water is indigo.

Interestingly, in the process of extracting indigo, an ancient beauty product is also derived. After the indigo paste is precipitated, stir at the remaining solution until the liquid surface has a rich foam, and these foams are dried, and they become ancient women’s eyebrows.


(嬛嬛 嬛嬛 是).

Dye, not so simple, then simple

Say that everyone may ask, is it to put these indigo water with water?

Of course not that simple.


In fact,

Extracting indigo from plants is only the first step in dyeing

The operation of truly reflecting the technical content is still behind.

Next, you should dilute the indigo extracted in the plant, and then add lime or other alkaline substances into the dyeing cylinder, and finally add rice wine or alcohol to confessed into a dye, and stand for a period of time. During this process, the dyeing liquid in the dyeing cylinder will develop a magical change – the blue is gradually disappeared in the dye, turns yellow green.

Is this a complex operation?

This has to be said from the properties of indigo. From the perspective of modern chemistry, indigo is


Indole natural dye

. This “high-cooled” substance is neither soluble in water and insoluble in alcohol, and there is no affinity against fabric fibers.

Conventional dyeing methods do not bring their color

The ancients added rice wine and alcohol in indigo-stained liquids, in order to let the microorganisms in the wine and alcohol make the liquid to ferment, restore indigo into blue green indigo. Indigo is reacted with an alkaline solution to become

Yellow-green huge color

This is why the dye is yellow-green. The hue can be “well-behaved” than indigo, but it is not only soluble in water, it is more likely to pick up cotton fiber.

So, how does the yellow-green huge column change back?

After the fabric is soaked in the dyeing liquid, it is necessary to place it in the sun.

Under the action of sunshine and air, the humerality is again oxidized into indigo

, Beautiful blue is reborn on the fabric.

Brazted flower pattern with dye, Wikimedia Commons, three hunting / cc by-sa 4.0

In fact, after these steps, I have to complete a few way.

Solid color process

The entire indigo dyeing process is completed. It’s hard to imagine that there is no chemical foundation, how to figure out such a complex set of processes.

Indigo Dyeing Crafts Blue This nature is extremely scarce color into people’s lives, even once become the most common color of the fabric.

The blue and Xunzi of jeans

Said so long of indigo, jeans? Don’t worry, this is not, jeans come!

Our familiar “denim blue” comes from the “blue” – indigo of the pen.

In the middle of the 19th century, it is positive in the US gold. A young man named Li Wei Strauss came to the United States San Francisco, opened a daily necessities, business is not bad, but the tent is always selling. Smart Li Wei is now that the workers wear cotton trousers are easy to break, so I think

Cut the bill of tailor into pants

. This canvas pants are very durable, and the workers like it, but it feels that the color is not bright enough, so he again


Staining cloth with indigo

So the margin of jeans is born like this.

Li Wei Strus is the founder of Jeans’s nasal ancestral brand Levi | Pixabay

Due to the lack of indigo, the phenomenon of local distilactation will appear after a period of grinding, showing the unique color of blue and white. However, it is precisely this faded characteristics that has achieved a fascinating temperament of jeans, so he has become a process of jeans production.

The era of born in jeans, the positive textile industry revolution swept the world. The high-speed development of the textile industry has led to a substantial growth of global dye demand, and the extraction of indigo from plants can not meet the growing market demand.

In 1890, Germany’s chemist H. Heumann invented the former Bayer.

Indigo synthesis method based on beaniline as the initial raw material

. Since then, artificial synthetic indigo achieves large-scale production and gradually replaces the plant indigo occupation market.

So today’s popular “denim blue”, actually from artificial synthetic indigo.

“Cowboy Blue” and Green Water Qingshan

Synthetic indigo and natural indigo are completely consistent in chemical structures. The principle of dyeing is also substantially the same as traditional blueprints – reducing indigo dyes into water-soluble indigo humerality (generally sodium sodium in-cell dyeing fibers ), Then drying fibers, via air or oxidant, oxidizing in the fibers, and then washing drying.

However, during ancient indigo dye, the materials used are taken from nature, and they can be modern.

Every link in the denim apparel production process is extremely unfriendled


Behind the boom of denim apparel industry, we are suffering from huge pollution pain | Pixabay

First, a large amount of chemical reagent is required during artificial synthetic indigo dyes, and the resulting waste slag is easy to cause environmental pollution. In the fabric staining stage, the current reducing agent “insurance powder” is not only polluting, but it is easy to absorb spontaneous combustion, which has huge safety hazard. Finally, in order to make jeans look more fashionable, after jeans is completed, manufacturers often use acrylic resins, phenolic compounds, potassium permanganate, hypochlorite, sodium pure base, coke phosphate, oxalic acid and hydrogen oxygen, etc. Chemical reagents do old processes in jeans, making it faded, wrinkled, and grinding.

Not only that, but the jeans production link is very water consumption, a jeans process takes 20 liters of water, and the global production of jeans, which is more than 700 million, the resulting sewage is amazing. said with no exaggeration,

Each wipes of denim blue is eroding our green water.

So, is there a way to take into account “Denim Blue” and green mountains?

In order to solve this problem, people have begun to reach the starting point of human society and indigo.

Combined with the wisdom of modern technology and the ancients, explore ways to take care of NET blue and green water

More than two more years ago, the ancestors found the method of microbial fermentation plant indigo, today’s scientists also got inspiration. They distinguish the microbiological species that can synthesize indigo, and use genetic engineering technology to enhance microbial production of indigo efficiency, so that these cute small organisms become a mini factory producing indigo, combined with large-scale fermentation technology,

Biological indigo

It can also return to our life.


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[2] Jiang Xiuzeng. Advances in research on clean production technology of indigo dyes. Special and discussion. 2018,07: 61-65


[3] Liu Yiping, Lu Ming, Wu Dayang. History of plant indigo dyeing and its development. Silk .2014, 11: 67-72

[4] Li Yufang. Study on the analysis and identification of several common Chinese ancient natural plant dyes. Beijing. Science and Technology History and Cultural Heritage Research Institute of Beijing University of Science and Technology. 2012020

[5] Zhang Ning, Liu Kewen. Yue is better than blue — indigo and life. Chemical education. 2008, 4: 78-79

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