01
Cannot achieve the desired feel
The soft style of soft finishing varies with customer requirements, such as soft, smooth, fluffy, waxy, oily, dry and slippery, etc. Different softeners are selected according to different styles. . For example, in soft sheets, there are softener sheets with different structures, which have different softness, fluffiness, smoothness, yellowing, and influence on fabric water absorption. In silicone oil, the properties of modified silicone oil with different modified groups are also different. , such as amino silicone oil, hydroxyl silicone oil, epoxy modified silicone oil, carboxyl modified silicone oil, etc., all have different properties.
02
Color turns yellow
Generally, the amino groups in films with amino structures and amino silicone oils can easily cause yellowing. Among soft sheets, cationic soft sheets have good softness and good hand feel, and are easy to be adsorbed on fabrics. However, they are prone to yellowing and discoloration, which affects the hydrophilicity. If the cationic soft sheets are modified into soft olein, the yellowing will be greatly reduced and the hydrophilicity will be reduced. Improvement, such as compounding cationic film with hydrophilic silicone oil, or compounding with hydrophilic finishing agent, its hydrophilicity will be improved. Anionic or non-ionic films are not prone to yellowing; some films do not turn yellow and do not affect hydrophilicity. Amino silicone oil is currently the most widely used silicone oil. However, amino groups can cause discoloration and yellowing. The higher the ammonia value, the greater the yellowing. You should use low-yellowing amino silicone oil or polyether-modified, epoxy-modified, etc. that are less likely to fade. Yellow silicone oil.
In addition, cationic surfactants such as 1227, 1831, and 1631 are sometimes used as emulsifiers during emulsion polymerization. These emulsifiers can also cause yellowing. Different emulsifiers are used when emulsifying silicone oil, and their “color stripping effects” are different, which will cause color stripping and light color under different circumstances; this is a discoloration.
03
FabricReduced hydrophilicity
Generally, there are problems with the structure of the film used, the lack of water-absorbing groups after the silicone oil film is formed, and the blocking of hydroxyl groups such as cellulose fibers and wool. The carboxyl, amino and other water-absorbing centers cause a decrease in water absorption, so anions and p should be used as much as possible; dark spots The main reason for dark spots is that the oil and sewage in the fabric is removed during pre-treatment, and the oil stain is darker in color during dyeing; or the dyeing bath There is too much foam in the medium, and the mixture of foam, floral fabrics, dyes, etc. is stained on the fabric; or the oil from the defoaming agent causes dark oil spots; or tar-like objects in the dye vat are stained on the fabric; or the dye agglomerates under different circumstances. Causes such as dark stains or excessive calcium and magnesium ions in the water combining with dyes and staining the fabric. It is necessary to carry out targeted treatment, such as adding degreasing agents for refining during pre-treatment, using low-foaming and non-foaming additives as dyeing auxiliaries, selecting defoaming agents that are not prone to oil drift, adding chelating agents to improve water quality, and adding solubilizing and dispersing agents. To prevent dye agglomeration, use tank cleaning agent to clean the tank promptly.
04
Light spots
The main reason for light spots is uneven pre-treatment, poor hair effect in some parts, resulting in certain dye-repellent properties, or containing dye-repellent substances, or during pre-treatment There are calcium soaps, magnesium soaps, etc. on the cloth, or the mercerization is uneven, or the semi-finished products are unevenly dried, or the cloth surface is stained with solids such as undissolved Yuanming powder, soda ash, or water drips on the dyed material before drying, or Stains caused by additives during finishing such as softening of dyed goods. Similarly, targeted treatment is necessary, such as strengthening pre-treatment. When selecting pre-treatment additives, it must be difficult to form calcium magnesium soap, and pre-treatment must be uniform and thorough (this is related to the selection of scouring agents, penetrants, chelating dispersants, mercerizing penetrants, etc. ), Yuanming powder, soda ash, etc. must be melted into the tank and production management must be strengthened.
05
Alkali spots
The main cause of alkali spots is incomplete or uneven alkali removal after pre-treatment (such as bleaching, mercerization), resulting in alkali spots. Therefore, the alkali removal process in the pre-treatment process must be strengthened.
06
Softener stains
The causes of softener stains may be as follows:
(1) The softening material is not good, and some Blocks of softener adhere to the fabric;
(2) There is too much foam after the soft sheet material is turned into soft sheets. When the cloth comes out of the vat, the softener foam is on the cloth. stains;
(3) The water quality is poor, the hardness is too high, and the impurities in the water combine with the softener to agglomerate on the fabric. Some factories even use sodium hexametaphosphate or alum to treat water. These substances form flocs with impurities in the water, which cause stains on the cloth after entering the softening treatment bath;
(4) The cloth surface contains anionic substances. When softened, it combines with the cationic softener to form stains, or the cloth surface contains alkali, causing the softener to agglomerate;
(5) Softeners have different structures, and some may cause the softener to change from an emulsified state to a slag-like substance that adheres to the fabric at higher temperatures;
(6) The original tar-like softener in the tank, etc.The material falls off and sticks to the fabric.
07
Silicon oil stains
Silicon oil stains are the most difficult type of stains to treat. The main reasons are:
(1) Cloth surface The pH value is not neutral, especially with alkali, causing the silicone oil to break and float;
(2) The water quality of the treatment bath is too poor, the hardness is too high, and the silicone oil It is easy to float oil in water with a hardness greater than 15Omg/L;
(3) Silicone oil quality problems, including poor emulsification (poor emulsifier selection, emulsification process Poor, emulsified particles are too large, etc.), not resistant to shearing (mainly problems with the silicone oil itself, such as silicone oil quality, emulsification system, silicone oil varieties, silicone oil synthesis process, etc.).
You can choose silicone oil that is resistant to shear, electrolytes, and pH changes, but you should pay attention to the use method and environment of the silicone oil. You can also consider choosing hydrophilic silicone oil. .
08
Poor fluff
Poor raising is closely related to the operation of the raising machine (such as tension control, raising roller speed, etc.). For raising, when applying softener (commonly known as waxing), control The dynamic and static friction coefficients of fabrics are key, so the preparation of fluff softener is key. If the softener is not used properly, it will directly cause poor fluffing, and even cause fabric breakage or door width changes.
09
Formaldehyde problem
The formaldehyde content exceeds the standard due to the free formaldehyde in the resin or the formaldehyde decomposed from the resin with N-hydroxymethyl structure. Ultra-low formaldehyde resin or formaldehyde-free resin should be used.
Of course, formaldehyde problems come from a wide range of sources, such as color fixing agents Y and M, softeners MS-20 and S-l, waterproofing agents AEG and FTC, and adhesives Additives such as RF and flame retardant THPC can sometimes cause formaldehyde to exceed the standard. At the same time, formaldehyde migration in the air may also cause formaldehyde on fabrics to exceed the standard.
10
Yellowing or discoloration problem
After resin finishing, yellowing will generally occur, so the pH value, acidic components, and catalyst components of the resin finishing agent must be controlled to minimize yellowing and discoloration. .
11
Powerful descent problem
General resin finishing will cause a decrease in strength, and fiber protective agents, such as oxidized polyethylene wax emulsions, can be added.
12
Feel problem
Generally, resin finishing will cause the hand feel to become hard. Soft ingredients can be added, but care should be taken not to affect the quality of the resin finishing. The hand feel has improved, and the problem of power drop has also been greatly improved. However, problems such as a hard feel caused by surface resin are caused by the resin itself and drying, and need to be improved accordingly.
13
Metal ions exceeding the standard
Metal ions Cu, Cr, Co, Ni, Zn, Hg, As, Pb, Cd, etc. need to be tested in export products. If they exceed the standard, they will have serious consequences like formaldehyde exceeding the standard. . Among the additives, there are relatively few metal ions of this type, but some additives can cause exceeding the standard. For example, the flame retardant antimony trioxide emulsion contains a large amount of mercury, and the waterproofing agent CR, phoboTexCR (Ciba), Cerolc (Sandoz), etc. chromium. When using mordant dyes on wool, the mordant dye used is potassium dichromate or sodium dichromate or sodium chromate, and Cr6+ will exceed the standard.
14
Color change problem
After finishing, there are many problems with color changes. This requires attention to the selection of dyes during dyeing. During dyeing and dyeing, corresponding finishing must be carried out according to the process. Determine whether the selected dye will change color under the action of additives. Of course, it is best to choose a finishing agent that will not cause color change. However, this often has limitations (for example, copper-containing antibacterial agents themselves have Color, chromium-containing waterproofing agents also have color, which will cause fabric discoloration). At the same time, factors such as light color and discoloration caused by dye sublimation during drying and baking of dyed fabrics and yellowing caused by excessive temperature should also be considered.
15
APEO exceeds the standard
APEO as an indicator is also strictly restricted by some countries. This indicator is related to scouring agents and penetrants in pre-treatment, cleaning agents and leveling agents in printing and dyeing, and post-processing. The emulsifiers in softeners during finishing are all related. As TX and NP series surfactants are still widely used as raw materials for additives, it is difficult to prevent them. The only way is for printing and dyeing factories to insist on using environmentally friendly additives and strictly prevent them. Additives containing APEO and toxic and hazardous substances enter the factory for use.
