SIZING INGREDIENTS AND FAULTS OF SIZING:-

SIZING INGREDIENTS:-

The chemical to be  used in the preparation of sizing liquor is called sizing ingredients. Sizing ingredients may be classified into two categories

1) Primary sizing ingredients.

2) Secondry sizing ingredients.

1) PRIMARY SIZING INGREDIENTS:-

The name and their role of primary sizing ingredients are given below;

(A) ADHESIVE AGENTS:-

The main role of adhesive agent in sizing liquor is to form a thin layer (film) on the yarn surface. It is a very important ingredient. A major portion of sizing liquor consist of  the adhesive ageni. It penetrates inside the yarn and increases the yarn strength. The protruding fiber also binds with the yarn surface and help to increase yarn strengh. The hairiness of the yarn is reduced too. Film on yarn surface improves the abrasion resistance and smoothness of warp yarn . Now these days following type of adhesive agents are used in sizing process. 

(B) SIMPLE STARCH:-

This is untreated starch powder. Mainly maize starch , sago starch , wheat starch and  potato starch are used as adhesive agents in sizing. The viscosity of sizing liquor  with untreated starch is always high. It gives poor penetration in the warp yarn. This starch is suitable for sizing of coarse count yarn upto 20's count.

The viscosity of untreated starch can be improved by adding potassium per sulphate in it and improved viscosity of liquor allow to use it in the sizing of medium count of yarn. It gives the best performance in weaving with the medium speed of loom. This is cost effective. It helps to control sizing cost per kilogram of warp. 

(C) THIN BOILING STARCH:-

It is chemically treated starch. It has a lower viscosity than untreated starch. It easily penetrates the yarn. When warp count increases , the size pick-up percentage is also increased, but the concentration of liquor is kept almost the same by using thin boiling starch. It may be successfully used in the sizing of medium count of yarn. It is a little expensive than untreated starch.

(D) MODIFIED STARCH:-

It is chemically modified starch. It has very low viscosity. It gives the best penetration effect in the yarn . It is suitable for all types of yarn count. It can be used for sizing of warp of high speed loom. Good quality of fabric results with this adhesive. Maximum effeciency can be achieved by using this adhesive. This is much expensive, so that it is used in the sizing of a fine count of warp yarn.

(E) BINDING AGENT:-

It is used to make the adhsive film enough strong. The adhesive film has brittleness . When it passes through various kind of abrasive actions and jerks during weaving, the adhesive filim becomes cracked and end breakage results during weaving. The binding agent provides strength to the adhesive film and or even  becoming a crack. There are many thyped of binding agents that are being used in sizing at present time. The widely using binding agent in today's sizing are given below.

Guar gum 

Carboxy methyl.

Cellulose (CMC) .

Polyvinyl Alchohal (PVA) .

Polyester binder (R-bind bilbind PS, eco size).

Acrylic binder (rain size excel) .

Above binding agents ate used individually or within combination according to requirements quality and the warp count is always taken into consideration before the selection of binding agents. 

(F) SOFTENING AGENT:-

It is used yo to make the adhesive film more soft and flexible. As well we know that the warp yarn process through different angle. So that the adhesive film becomes crack due to the bending movement of the yarns. The problem necessiates that  the adhesive film should be soft and flexible. The softening agent provides enough softness to the adhesive film. It is also makes the yarn surface smooth. Following types of softening agents are used now these days.

Vegetable fats (dalda, refined oil).

Animal fats ( mutton tallow) . 

Synthetic softner (R-soft , textile wax) .

A little smount of softener is used in the sizing liquor. It does not affect the costing of sizing process on many scale. 

(2) SECONDARY SIZING INGREDIENTS:-

The secondary sizing ingredients of sizing agents are given below.

(a) Antistatic agent:-

It prevents the generation of electrostatic charge in the warp during weaving . When the warp makes up and down mivement during weaving , the ends rub to each other and generates an electrostatic charge in the warp.  These electrostatic charges cause warp breakage during wraving . A very little smount of antistatic agent is used in the sizing liquor . The types of antistatic agents are given below;

Sepcostate.

LV-40.

PAA-40.

(b) Antiseptic agent:-

It is usefd to prevent bacteria mildew formation in the sized beam or fabrics, woven from a sized warp when the sized Warp or fabric remains unused , there are chance of bacteria or Mildew formation in humid conditions or rainy season. Some antiseptic agents is added to the sizing liquor to avoide this problem,

Salicylic acid.

Zinc chloride.

Phenol.

Emulsifier.

Copper sulphate.

(c) Hygro scopic agent:+

The main role of the hygro scopic agent in the sizing liquor is to improve the moisture absorption capacity of warp from the air . Since we know that the strength of cotton increases by increasing moisture percentage where the warp absorbs the moisture during weaving , the warp break rate is reduced . The majority using hygroscopic agents are given below;

French chock.

China clay.

Ref:-https://www.textileadvisor.com

Main reasons of Sizing Faults:-

SIZING DEFECTS:-

After applying sizing process , different types of change occured such as increse friction resistance, flexibility, smoothness, etc. During completing this process several defects are produced which are to observed care fully.

-FAULTS OF SIZING:-

There are different types of sizing faults arise in sizing process of weaving technology which are given below;

1) Uneven Sizing.

2) Hard Sizing.

3) Sandy warp.

4) Size spot.

5) Shinney.

6) Size dropping.

7)Ridge Beam.

8) Improper drying.

9) Sizing stitching.

10) Repeating warp streaks.

The causes for above fault and their remedies of sizing have been explained as under.

(1) Uneven Sizing:-

CAUSES:-

It arise due to under and over sizing process.

It arise because of under and over cocentration of size liquo

.(2) Hard Sizing:-

CAUSES:-

When sizing ingredients applied too much in the warp yarn , the size become too much hard which ultimately causes hard sizing.

(3) Dandy Warp:-

CAUSES:-

This type of fault produce due to grind or crushed the sized material not perfectly.

(4) Size spot:

CAUSES:-

During sizing process in warp yarn, sizing ingredients must be added gradually into the chemical mixing tank for perfect mixing of chemical. If it is not happened, then this type of fault is produced.

(5) Shimmery:-

CAUSES:-

This type of defect produced because of the friction between drying cylinder and sheet of warp yarn.

(6) Size droppin:-

CAUSES:-

This type of defect should be removed as soon as possible which is produced due to not optimum viscosity of the sizing solution.

.(7) Ridge Beam:-

CAUSES:-

 Ridge beam fault is produced due to unequal distribution of yarn wraith during sizing.

(8) Improper dyeing:-

CAUSES:-

 Here in case of over drying hard sizing defect produced and in case of over drying bacteria forms. As a result yarn breakages occurs.

(9) Warp Sticking:-

CAUSES:-

When drying will not perfect , after sizing process this type of fault produced.

(10) Repeating Warp streaks:-

CAUSES:-

Repeating warp streaks defects are produced in warp because of improper tension pre-beam.

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