Twelve uses of soda ash in printing and dyeing industry

1.软水剂：

1. Water softener:

为了避免在印染加工过程中生成不溶於水的钙、镁肥皂或染料沈淀，可采用适当的方法以去除水中钙、镁等盐，这种处理过程叫做水的软化。

In order to avoid the formation of water-insoluble calcium and magnesium soaps or dye deposits in the printing and dyeing process, appropriate methods can be used to remove calcium, magnesium and other salts in the water. This treatment process is called water softening.

水中加入纯碱能使钙离子或镁离子成为碳酸盐而析出，从而达到软化作用。

Adding soda ash to water can make calcium ions or magnesium ions become carbonates and precipitate, so as to achieve softening effect.

2.煮练剂：

2. Scouring agent:

色纱织物是由经过染色的纱线和没有经过练漂的原纱织成，两者的比例随品种而不同。像格子花呢一类，色纱所占的比例很大，条格府绸一类，色纱所占的比例就少得多。色纱织物的煮练不能用一般棉布煮练的工艺条件，因为织物中的条格色纱大多用硫化、还原、纳夫妥等染料染成。

Colored yarn fabric is made of dyed yarn and raw yarn without scouring and bleaching. The proportion of the two varies with the variety. Like plaid, the proportion of colored yarn is very large, while that of checked poplin is much smaller. The scouring of colored yarn fabrics cannot use the general cotton scouring process conditions, because the Striped colored yarn in the fabric is mostly dyed with dyes such as vulcanization, reduction, NAFTA, etc.

这些染料在高温、高压的烧碱强碱液中剧烈煮练时，容易溶落下来而沾污白地，造成严重搭色。因此，格子花呢和格子府绸煮练时，就不能用烧碱，而只能单独用纯碱，且煮练时不能加压，而是要在开口煮布锅中常压下进行，以免剥落嵌条色纱的色泽而污染白地。

When these dyes are vigorously digested in high temperature and high pressure caustic soda, they are easy to dissolve and stain the white ground, causing serious color matching. Therefore, when plaid and plaid poplin are cooked, soda cannot be used, but only soda alone, and the cooking cannot be pressurized, but should be carried out under normal pressure in an open cloth cooking pot, so as not to peel off the color of the Striped yarn and pollute the white ground.

3.乳化练毛剂：

3. Emulsion scouring agent:

生羊毛纤维因含有多量灰尘杂质，不适於纺织工程，故多在纺毛前将原毛施行洗毛。一般利用纯碱及肥皂，使羊毛上脂肪杂质成乳化体而去除。

Raw wool fiber is not suitable for textile engineering because it contains a lot of dust impurities, so it is often washed before spinning. Generally, soda ash and soap are used to remove fat impurities on wool into emulsions.

其法每千份水中加纯碱3～10份，及肥皂2～5份，於45℃时搅拌精练，用温水清洗。

The method is to add 3 ~ 10 parts of soda ash and 2 ~ 5 parts of soap per thousand parts of water, stir and refine at 45 ℃, and wash with warm water.

4.精练剂：

4. Scouring agent:

毛线及毛织物因原毛已经精练，只是为了再除去纺织时所加的滑润油及制造时沾著的污迹而已，手续远较精练原毛简易。通常用织物重的2～4％纯碱及1～3％肥皂，温度35～40℃。

Wool and wool fabrics have been refined because of raw wool, just to remove the lubricating oil added during spinning and the stains stained during manufacturing. The procedure is much simpler than that of refined raw wool. Usually, 2 ~ 4% soda ash and 1 ~ 3% soap of fabric weight are used, and the temperature is 35 ~ 40 ℃.

5.练丝用剂：

5. Silk scouring agent:

蚕丝纤维主要为丝纤维与丝胶质组合而成，其他杂质甚少，仅含微量蜡质脂肪。丝胶质含量达30％左右，包覆於丝纤维质外部，其化学成分虽与丝纤维质相似，但缺乏光泽，性质粗硬，欲发挥丝的柔软光泽特性，应将丝胶质充分除去。

Silk fiber is mainly composed of silk fiber and silk colloid, with few other impurities and only a trace of waxy fat. The content of silk colloid is about 30%, which is coated on the outside of silk fiber. Although its chemical composition is similar to that of silk fiber, it lacks luster and is rough and hard. In order to give full play to the soft luster characteristics of silk, the silk colloid should be fully removed.

丝胶质能在含肥皂及弱碱性的热水中软化溶解，丝纤维质则不溶，利用此项特性，故有肥皂练丝法及纯碱练丝法。

Silk colloid can soften and dissolve in hot water containing soap and weak alkaline, while silk fiber is insoluble. Using this property, there are soap silk scouring method and soda ash silk scouring method.

6.染棉助剂：

6. Cotton dyeing auxiliaries:

纯碱用作直接染料染棉助剂，能起缓和染著和软化硬水的作用。又硫化染料染棉时，除加硫化钠作染料溶剂外，常加纯碱若干，以辅助溶解染料。若硫化碱的功效十分充足时，就不必加用纯碱。此外如还原染料也常加纯碱若干以作辅助染剂。

Soda ash can be used as an auxiliary agent for cotton dyeing with direct dyes, which can ease the dyeing and soften hard water. When dyeing cotton with sulfur dyes, in addition to adding sodium sulfide as the dye solvent, some soda ash is often added to assist in dissolving the dyes. If the efficacy of alkali sulfide is very sufficient, it is not necessary to add soda ash. In addition, vat dyes are often added with soda ash as auxiliary dyes.

7.色浆碱剂：

7. Color paste alkali:

有些还原染料如士林艳桃红R、蓝3G等比较容易氧化，且对烧碱也很敏感，因此以强碱作为它们溶解用的碱剂时，往往会使印花后的得色较暗而带紫光；为了克服这一疵点，常用纯碱来代替烧碱。dyebbs

Some vat dyes, such as Shilin brilliant peach red R and blue 3G, are relatively easy to oxidize and are also very sensitive to caustic soda. Therefore, when strong alkali is used as the alkali agent for their dissolution, it often makes the color after printing darker and purple; In order to overcome this defect, soda ash is often used to replace caustic soda. dyebbs  

此外，由於烧碱或碳酸钾的吸湿性能都比较强，蒸处时某些著色拔染印花的色浆，在花型边绿往往产生色晕，为了克服这个毛病，也常以纯碱代替烧碱或碳酸钾。

In addition, due to the strong hygroscopic properties of caustic soda or potassium carbonate, some dye discharge printing pastes tend to produce color halos when steaming. In order to overcome this problem, soda ash is often used instead of caustic soda or potassium carbonate.

8.净洗剂：

8. Detergent:

一般色布与印花布后处理时，常以纯碱与肥皂合用为净洗剂。肥皂为脂肪酸的钠或钾盐，是良好的净洗剂。肥皂在稀溶液中会发生水解，浓度到达0.16～0.2％时净洗能力即达到高峰。

In the post-treatment of general colored and printed fabrics, soda ash and soap are often used as detergent. Soap is the sodium or potassium salt of higher fatty acids, which is a good detergent. Soap will be hydrolyzed in dilute solution, and the washing capacity will reach the peak when the concentration reaches 0.16 ~ 0.2%.

为了获得充分的去污能力，尤其是污垢较多时，应将它的浓度提高到0.5％左右。为了抑制稀溶液（小於0.1％）中肥皂的水解，可在洗液中加入0.1％的纯碱，在较浓的洗液中纯碱的用量应酌予减低。纯碱并对硬水有软化作用，从而发挥了肥皂的洗涤作用。

In order to obtain sufficient decontamination capacity, especially when there is much dirt, its concentration should be increased to about 0.5%. In order to inhibit the hydrolysis of soap in dilute solution (less than 0.1%), 0.1% soda ash can be added to the washing solution, and the amount of soda ash in thicker washing solution should be reduced. Soda ash also softens hard water, thus giving play to the washing effect of soap.

9.固色剂：

9. Color fixing agent:

活性染料在棉纤维或合成纤维上染色时，是借碱性物而固色的，用温和碱性物如碳酸钠的稀溶液，可得优良效果。用量可根据色泽浓度而酌量增减。

When reactive dyes are dyed on cotton or synthetic fibers, they are fixed by alkaline substances. Good results can be obtained by using a dilute solution of mild alkaline substances such as sodium carbonate. The dosage can be increased or decreased according to the color concentration.

例如普通型活性染料进行卷染，大多在第5～6道时，於染浴中加入纯碱约1％（对染液汁）作为固色剂。一般染色6道、固色6道，温度20～21℃。

For example, when ordinary reactive dyes are used for jigging, about 1% of soda ash (for dye juice) is added to the dye bath as a fixing agent in the 5th to 6th passes. Generally, there are 6 dyeing and 6 fixation, and the temperature is 20 ~ 21 ℃.

10.防白用剂：

10. Anti whitening agent:

阿尼林黑防染印花的防白糊调制时，除加用锌氧粉、增白剂外，再加用纯碱约70～100克∕升，将阿尼林黑染料成分中的盐酸抵消，使阿尼林黑不能发色，从而达到防白效果。也有采用醋酸钠代替纯碱作防染剂，但防白轮廓不及用纯碱的清晰。

When preparing the anti white paste of anilin black anti dye printing, in addition to adding zinc oxide powder and brightener, add about 70 ~ 100 g / L of soda ash to offset the hydrochloric acid in the anilin black dye components, so that anilin black can not be colored, so as to achieve the anti white effect. Sodium acetate is also used to replace soda ash as anti dye, but the anti white outline is not as clear as that of soda ash.

11.“风印”用剂：

11. "Wind seal" agent:

活性染料含有反应性基团，可和纤维结合而固著。目前常用染料有低温固著（X型或普通型）、高温固著（K型或热固型）。染者无疆编辑

Reactive dyes contain reactive groups, which can be bound to fibers and fixed. At present, the commonly used dyes are low-temperature fixation (X-type or ordinary type), high-temperature fixation (K-type or thermosetting type). Dyer Wujiang editor

活性染料在棉布上直接印花具有色泽鲜艳、牢度优良、不受光化影响而引起纤维脆损等优点。但它还存在不耐氯漂以及所谓“风印”的缺点。

The direct printing of reactive dyes on cotton fabric has the advantages of bright color, excellent fastness, and no fiber brittleness caused by photochemistry. However, it is not resistant to chlorine bleaching and the so-called "wind print" shortcomings.

“风印”是指印花加工品露於空气部分有不规则的色淡，这主要是由於印花织物在汽蒸固色前，露置空气部分与酸气起了中和作用，削弱了染料赖以固色的碱剂。因此印前白胚布预轧足量碱剂（一般轧吃纯碱20克∕升），不但使染料基本上可以克服风印，而且给色量有显著提高。此外，印后的花布用薄膜或棉罩四周包裹，不使花布有局部露出，待汽蒸后，就不再产生风印疵病。

"Wind printing" refers to the irregular light color of the exposed part of the printed fabric in the air, which is mainly due to the neutralization between the exposed part of the printed fabric and the acid gas before steam fixation, which weakens the alkali agent on which the dye depends for color fixation. Therefore, pre rolling sufficient alkali agent (generally 20 g / L soda ash) for prepress white embryo cloth not only makes the dye basically overcome wind printing, but also significantly improves the color giving amount. In addition, the printed cloth is wrapped around with a film or cotton cover to prevent partial exposure of the cloth. After steaming, there will be no wind printing defects.

12.清晰剂：

12. Clarifier:

缩聚翠蓝I5G在棉布上直接印花，印前白坯布预轧足量碱剂（纯碱20克∕升），印花后经汽蒸，对染料给色量、水洗牢度、细条轮廓清晰都有显著提高。

Polycondensated turquoise blue i5g is directly printed on cotton cloth. The white cloth is pre rolled with sufficient alkali agent (20 g / L of soda ash) before printing. After printing, it is steamed, which significantly improves the dye dosage, washing fastness and clear outline of thin strips.

但纯碱不宜代替小苏打在印花色浆中作碱剂，因以纯碱10克∕升代替小苏打10克∕升，虽可缩短汽蒸时间，但得色较暗，色浆稳定性也差（用小苏打色浆可放置3～4天，用纯碱的只有8小时）。

However, soda ash should not replace baking soda as an alkaline agent in the printing paste, because using 10 g / L of soda ash instead of 10 g / L of baking soda can shorten the steaming time, but the color is darker and the stability of the paste is poor (the paste with baking soda can be stored for 3-4 days, and only 8 hours with soda ash).