Selection of knitted fabric dyeing auxiliaries common quality problems

1. color fastness unqualified
Color fastness to light fastness, washing fastness, perspiration fastness, rubbing fastness, fastness to open China, ironing fastness, these fastness lies dye structural performance, but also with the fibers, dyes closely related to the concentration, dyeing and finishing processes, external conditions, so whether the target color fastness, the key is to choose the dye, followed by dyeing and auxiliaries applications.

When dyeing system permits must be based dyes, fibers and customer indicators reasonable assurance that the dye additives help, under certain conditions, as far as possible on the ground dye fastness fiber to make it fully fixed. For the additives, the first, a good choice and pro-dye leveling agent, the dye slowly and evenly, fully dyeing fibers; Second, plus a chelating agent to overcome the dye and metal ions from the water floating color, and reduce hydrolytic activity of the dye in the water; Third, choose good soaping, go to the net floating color, and anti-floating re-stain fabric;; fourth is to select the appropriate fixative, the current sublimation fastness, sun outside fastness is no ideal fixative for soaping fastness, perspiration fastness collapse, the indicators rubbing fastness, etc. are excellent fixative to choose from.

2. brittle damage
Brittle damage showed a strong decline in profit before oxygen bleaching due to improper handling and other processes cause damage or even brittle outer holes and other reasons, there are generally two types of brittle damage caused by dyeing reasons, one is brittle damage such as sulfur black dye caused required to improve the anti-brittle agent, as well as dyeing vat dyes and strong oxidizing agents strong reducing agents, such as damage to the fibers brittle; Second stage or the improper dyeing and stages with acid, and acetic acid is generally used, and currently on the market supply of some alternative acids, some of these alternative acids like BASF’s strong organic acid buffer, excluding sulfuric acid, hydrochloric acid, phosphoric acid, and even superior performance than acetic acid, the chemical company Ningbo Runhe buffer acid is also true these buffer acetic acid but also to improve some of the shortcomings (such as glacial acetic acid winter inconvenient to use, stimulating taste great, residual acidity, and metal ions in water such as Ca +2 Mg +2) remain in the fabric caused by the combination of dark shade wilt etc. etc.). Some with H2SO4, HCl, H3PO4 and other alternative acid, not only cause changes in dyeing shade, dyeing and finishing equipment and pumps for corrosive effect, but during and after the acid residues can also cause fabric damage brittle under acidic conditions.

3. Wrinkle Article
Wrinkles are generated mainly of equipment reasons, the amount of cloths has installed causes the bath ratio and the processing operation of the reasons and other reasons, the amount of fabric mounted equipment, the pressure and friction between the pump power and the tension of the fabric and the fabric are affected fabric cloth flatness; bath ratio will affect the size of the flatness of canvas; process operations caused by too much fabric floating foam additives and process skid heating and cooling operation appears cold and hot phenomenon will cause fine wrinkles of the phenomenon . The current bath lubrication wrinkle agent, bath treasure, bath softener can improve fine wrinkles of the phenomenon, but if the device does not improve, poor process control, plus bath lubricant alone can not completely avoid the fine wrinkles of produced.

4. Wind India
Air India has little to do with the additives, the key is to dye their own performance (acid resistance) and fabric with pH, acid gas air humidity and so on, such as direct dyes Fast Turquoise Blue GC, chrysophenine G, etc. in case of sour gas prone to wind and India; activity in Turquoise Blue KN-G, brilliant orange X-GN and other pH sensitive and easy to produce on wind India; dyes such as yellow RGFL in base-sensitive, but also easy to produce wind India . For aid, the middle and must do to make cloth as pH = 7. Therefore, attention must also breed and when acids and bases, as far as possible with glacial acetic acid or organic acid substitution, can never substitute acid containing H2SO4, HCl and other strong inorganic acids, bases with Cheung also choose to ease as much as possible Some.

5. color flowers (including color, color does not match the sample, etc.)
Flower color dyeing process is the most common, the most common quality problems, the causes are:
(1) the development and operation of process issues: developing technology to produce an unreasonable or improper operation flower color.
(2) equipment problems: If the disperse dye polyester heat-setting machine inside the oven temperature varies also easy to produce color-color flowers, dyed rope pump power shortage also cause colored flowers.
(3) Dye problem: dye aggregation prone, poor solubility, poor compatibility, temperature, pH is too sensitive and are easy to produce color flower color. Reactive Turquoise Blue KN-R as easy to produce colored flowers.
(4) water quality problems: poor water quality, causing the dye and metal ions or dyes and impurities caused by condensation flower color, light color, the color does not match the kind of phenomenon.

Problem with colored flowers are mainly related to penetrant additives, leveling agents, chelating dispersant, pH value control agents penetrant penetration enough, could easily lead to uneven color dye penetration flowers, such as casual cotton dyeing, cheese dyeing effect, heavy fabric dyeing, penetrant can not be ignored, and some believe only authentic factory penetrant JFC, but did not take into account the cloud point JFC only 38-42 ℃, More than 42 ℃, its penetration force it to play out, will cause quality problems. There leveler with polyester, cotton with wool, nylon used, with all kinds of acrylic leveling agent, and the quality is uneven, leveler selection must take into account the effect of dispersing the dye solubilization, retarding migration effect, Help osmosis or complexation of metal ions in water, and must take into account various factors which PH applicability, foam and other effects on the rate of color. Leveler to improve the color of flowers, color point and so contributed, some plants leveler just solution diffusion agent N, but did not think the proliferation of agents N at a high temperature resistant dyes its unifying role greatly reduced; there the plant selection nonionic surfactants are not suitable, resulting in more than the cloud point nonionic surfactant itself precipitated dye adsorbed from tarry substance or apparatus into the fabric, but cause quality problems. Quality chelating dispersant leveling problems are related, in the current water quality is getting worse, the chelating dispersant leveling should help more attention. pH control problem is a problem of the plant too seriously, pH and some plants are not the same for each cylinder stained, with some plants using different acid substitution of quality, such as containing phosphate, pH phosphate are three ionization there are differences in how to control a uniform pH: pH slip agents using some plants, but not such as to grasp the relationship between the pH and the temperature and time generated between the slip agents, pH control of the question, so that the flower color, the phenomenon of color continue to produce.

6. color point (including white point)
The reason there are many color points generated, such as white spots, may be non-mature cotton is not the cause of the dye, it may be caused by the local soda ash and other solid stick and other reasons not to dye the cloth. Color point is the main reason:
(1) Dye inappropriate choice: dye particles are too large or easy to produce condensed color point;
(2) performing a dye dissolved: not dissolved dye into the fabric from sticking to the dye color point;
(3) water quality is poor: poor water quality caused by dye condensation;
(4) the device without a net: vat of tar-like substance under the swap cause color point;
(5) Auxiliary Reason: added in dyeing auxiliaries sometimes cause the dye to produce color point but agglutination; aids too much foam, foam with a colored dye binding bubbles stick to the fabric to form color point; additives and dyes precipitate combined with the device sticks to the fabric, and agglutinates will turn the device on the color point of the dip caused by the fabric.