Improvement Trend Of Mercerizing Process And Equipment

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Due to the high speed and high output before the scouring and bleaching, the mercerizing speed is required.

The conventional cloth mercerizing locomotive is only 50 to 60m/min, while the high-speed mercerizing machine reaches 100 to 150m/min, which can solve the "bottleneck" problem of mercerizing, but the requirements for the components of the mercerizing machine are high.

We can start from the following aspects: enlarging the alkaline bath, increasing the time of alkali leaching and increasing the roller.

Increase the number of times of suction (5 scours and 5 sucking above), increase the number of alkali removal tanks, and enhance the effect of alkali removal.

High efficiency washing (such as high frequency oscillation washing, pverse guide roller, straight guide roller, etc.).

Because of its fast speed and large abrasion, the alloy steel or wear-resistant plastic gasket should be used.

Neutralize neutralization in flat wash to ensure that the pH value of cloth is between 7~8.

Wet cloth mercerizing.

The main advantages of wet mercerizing are: (1) fibre puffing foot, uniform alkali absorption, uniform product quality, good levelling property; 3. Width of fall cloth door; 4.

Attention should be paid to the problem: the size and uniformity of water content on the cloth. It is required to immerse the alkali evenly before rolling, rolling the liquid at a rate of <60%, and stabilizing the alkali concentration. The first alkali tank can be divided into two grids before and after, and the concentrated alkali of 300g/l is in the back lattice, then flows back to the second alkali tank through the overflow pipe, and then flows back to the front edge of the first groove, so that the capacity of the alkali tank is small, the liquid exchange is fast and the balance is convenient.

At the same time, the fabric first contacts with weak alkali and then contacts with strong alkali, which is favorable for the infiltration of alkali into the fiber and fully and evenly expanding, so that the mercerizing effect is guaranteed.

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The conventional mercerizing process is room temperature mercerizing (18~20 degrees). The caustic solution is thicker and less permeable. It is easy to cause "surface mercerization", and the thick and tightly woven fabric needs uniform and thorough effect.

Heat and alkali permeability is good, but puffing is poor.

Therefore, the mercerizing process with first hot alkali and later cold alkali is adopted.

The early infiltration of hot alkali is conducive to the continuous infiltration of cold lye, so that the fabric has more alkali content, resulting in uniform and effective expansion.

The procedures are as follows: fabric loosening and rolling, dense alkali (boiling point, 5S above), thermal stretching, cooling, tension down alkali, alkali removing box and horizontal washing tank.

Main advantages.

The mercerizing effect is uniform and the effect is good. Luster, strength and dimensional stability are superior to regular mercerization. It can be combined with the scouring process, shorten the process route, reduce the cost and increase the economic efficiency (before heating, steaming hot alkali fabric steamed 10 ', normal pressure).

Vacuum core mercerizing.

According to the German company of Claire, a vacuum hood is installed on the first roller of the roller mercerizing machine and connected to the vacuum pump (to 10kPa). When the fabric passes through, the residual air can be removed, so that the alkali can infiltrate quickly and evenly before the fiber swelling, thereby shortening the impregnation time and improving the efficiency, but the equipment is complex, and the cost is large when running at high speed.

Penetration agent is added to mercerized lye.

The French used more outside the country, because of the impact of light alkali recovery, rarely used.

Foam mercerizing.

The advantage is that it can save caustic soda and single sided mercerization. The key is to select the ideal foaming agent and obtain stable foam mercerizing liquid. After being impregnated, the foam can break quickly and infiltrate into the cotton fabric to obtain a uniform alkali leaching effect.

In addition to foaming agent, 0.1 to 0.2% penetration agent is needed. The technology is still under study.

Application.

Silk wrinkle is one of the common defects of mercerized fabrics. Once formed, it is difficult to remove them.

The hard uneven scale will also wrinkle the fabric.

Adding scale inhibitor in mercerizing and washing can solve the problem of or improving scaling.