Scouring Agent

The dyeing and printing of textile products need to be done in a certain way to remove impurities and oil stains on the cloth surface. This cooking process is often called scouring. And in the refining of various types of infiltration, emulsification, washing, dispersing, wetting function of chemical auxiliaries, called scouring agent.

During the refining process, the scouring agent is through its wetting effect, the weakened adhesion of the oil wax and the fiber in the fabric, and the gradually reduced interface, to make the oil wax fall off the fabric. At this time, the oil wax particles and water contact surface increased, forming a very unstable system, the surfactant in scouring agent has emulsifying and dispersing effect, which is easy to form micelles in water, and the oil wax wrapped in the micelle to form a comparatively stable system, which can prevent the oil grains from being deposited on the fabric. On the other hand, with the help of the wetting effect of surfactants, in a certain temperature and sufficient time conditions, the caustic soda and fiber impurities fully effect the decomposition, and the decomposition of its solution or the use of surfactants dispersed in scouring fluid, by washing and removal.

In a broad sense, the addition of acid, alkali, oxidant, reducing agent and all kinds of surfactants can be called scouring agent in scouring process. But in the textile industry, generally speaking of scouring agent in textile, mostly the concept of narrow sense, mainly refers to all kinds of anion, non-ionic surfactants and appropriate additives, through a certain proportion of the method to get a washing effect, and with infiltration, emulsification, dispersion, complexion and other synergistic effects of the complex. Because the scouring of fabrics is a very complex physical and chemical process, in the surface chemistry scouring agent emulsification, dispersion, and chelate metal ions ability are very important properties, and these properties alone in some surfactants is difficult to complete. All kinds of surfactants have their own advantages and disadvantages, thus the scouring agent is often composed of a number of different types of surfactants. The current scouring agent in the market is generally composed of nonionic and anionic surfactants.

Scouring process is that the desizing of cotton cloth boiling in a certain concentration of caustic soda solution for several hours, or soaking up in the alkali steam for a certain time, which make the fat wax in cotton fiber saponification, emulsification, pectin for pectin salt; the cotton seed shell easy to wash away; and the residual slurry further expanded and removed. Synthetic fibers do not contain natural impurities, generally in no need of scouring. However, in the cotton blended fabric, the cotton fiber contains more impurities, scouring is still required. 

Scouring Agent of Cotton Fabric

[Brief information]
--It is widely used in textile processing. It has good emulsification, dispersion, penetration ability, can remove all kinds of dirt fabric, grease substance, floating color.

[Main composition]
--Variety of mixed surfactant compound.

[General properties]
--Appearance: colorless transparent liquid
--Ionicity: nonionic
--pH: 6 – 7
--Stability: stable to acid, alkali, water and electrolyte.
--Solubility: easily soluble in water

[Properties and fields of application]
--It is mainly used for pretreatment process for removal of sizing agent and oil.
--It has excellent emulsification, dispersion, penetration and dissolution in oil for sizing agent and chemical slurry.
--Greatly improve the quality and efficiency of pretreatment auxiliaries, with low foam and easy cleaning, also save water.

[Application]
Under a variety of conditions, it has outstanding penetration. Suitable for the pretreatment and dyeing of cotton and blended fabric.

--Pretreatment: 1 - 3g/l
--Staining: 1-3g/l

Low Temperature Scouring Agent in Textile HT-DJ133

[Main composition]
-- Surfactant compound.

[General properties]
-- Appearance: colorless to pale liquid
-- Ionicity: nonionic
--pH: 3-5(1% solution)
--Solubility:  easily soluble in water
--Stability: stable to acid, alkali and electrolytes

[Properties and fields of application]
--Pretreatment at 80-90 ℃ can achieve traditional oxygen bleaching scouring effect, great energy-saving.
--Suitable for cotton, polyester-cotton fabric, yarn and fiber one-time pretreatment, good effect, less weight loss and good hand feeling.
--Free of AEPO any harmful chemical substances and meet the requirements of environmental protection, reduce COD/BOD.
--Reduce wrinkle of the blended fabric in high-temperature conditions and the tear and  bursting strength are not damaged

[Application]
High concentration product can dilute 3 times.
Dipping :(cotton knit, cheese)
Scouring agent:  1-2g/L
NaOH: 2g/L
H2O2:  5 g/L
Hydrogen peroxide activator: 2-3g/L

[Process]
Bath ratio 1:8, with 2-3℃/ min heating to 80-85℃, heat preservation for 60-90 min.

Alkali resistant scouring agent 1042P

[Main composition]
-- Compound of various surfactants.

[General properties]
-- Appearance: Light yellow paste
-- Ionicity: anionic/nonionic
-- Stability: stable to electrolytes, oxidants and 180 g/L of NaOH
--Solid content: 80%

[Properties and fields of application]
High concentration product and can be diluted 3-5 times.
-- Wide application range for desizing, scouring and bleaching of cellulose fibers and their blends.
-- Alkali resistant and good compatibility.
-- Good whiteness and outstanding re-wetting with high efficiency and low cost.
-- Free of APEO and complies with environmental requirements.

[Application]

Desizing
Amylase	3-8 g/L
NaCL	3-5 g/L
HT-1042	1-3 g/L
NaOH	1-3 g/L

Scouring
HT-1042	5– 10 g/L
NaOH	40-60 g/L
Sequestering agent	2-4 g/L

Bleaching
HT-1042	1-3 g/L
H2O2(100%)	3-6 g/L
Bleaching stabilizer	3-6 g/L

-- Steaming process: 95-102℃ × 45-60 min

[Packing and storage]
-- Packing: 125 kg/polyethylene drum
-- Storage: Keep it cool and dry, 6 months in sealed container at room temperature.

The Test of the Properties of Scouring Agent Determination of textile's Whiteness

There are so many testing methods of whiteness, and the reliability and applicable range are varied, especially as the increasing use of the fluorescent whitening agent in recent years, making the determination of whiteness become much more complicated. Nowadays, the determination of whiteness can be divided as two kinds generally: the first one is to use the spectrophotometer to determine the reflectance of each wavelength. The L value, a value and b value are obtained by computer calculation, and then the whiteness is obtained by the whiteness calculation formula. At present, there are a lot of whiteness calculation formulas, but they are all have weakness, proving that it is hard to find a formula that is corresponded to the fact. Taking ZBD whiteness calculation as an example: Determination of the specific wavelength light through the filter that transmitted wavelength less than 500nm is irradiated to the sample light except for the blue light, and purple light, so that whiteness measurement can be carried out with samples of fluorescent whitening agents. In the determination, the instrument is adjusted with a standard white plate, and then the relative whiteness of the sample is determined.   

1. Instrument. XBD  whiteness calculation.

2. Operating steps. To cut the semi-cloth products with no optical brightener for 12cm refined * 24cm, and fold into 5cm * 5cm 8 layers (thin fabric is 18cm * 24cm, 5cm * 5cm folded into 12 layers). And then to determine whiteness in whiteness meter, which requires each specimen shall keep the warp and weft consistent. In this case it should be measured 3 times in different parts, and eventually to take the average value.

3. Illustrations
◎ Other instruments which can determine or can calculate after determination are favorable to be applied. Even though the data gained may not consistent, using the same instrument to determine the data can still illustrate the situation about whiteness. The date of whiteness given in the report should be marked the type of the instrument.
◎ The layers folded of textile should be the same.