Splashing and cracking of print paste easily occur mostly when the drying process is being carried out after printing. The following can be some of the causes:

1. Poor elasticity of thickener film
2. Poor compatibility of thickener with dyestuffs, auxiliaries and chemicals
3. Over-drying on printed areas
4. Unevenness on printed surface
5. Poor or too good penetration on printed areas
6. Treatment after printing
   (a) During removal of printed materials from the table after printing
   (b) During rewinding the cloth before steaming
   (c) During steaming
7. Adhesion due to static electricity
8. Designs such as line-delineation, all over and white ground

One of the ways to prevent problems is, in the case of 1., to choose thickeners with good film elasticity. The film formation of each thickener is indicated in Figure 1.

Figure 1. Surface of each print paste after dried.

The figure shows the condition of each thickener dried after being printed on a glass plate. From this picture, it is understood that guar gum, CMC and sodium alginate are effective in order to reinforce the elasticity of the film.

Glycerin, polyethylene glycol and urea are recommended as hygroscopic agents. However, if an excessive amount of these is used, the drying speed will be reduced, therefore, chafe marks may be caused. In the case of 2., thickeners generally have poor compatibility with dyestuffs, chemicals and auxiliaries.

There are many cases of film deterioration: especially in the case of printing deep shades (black, navy etc) with disperse dyestuffs.

Thus, in such a case, it is necessary to change the thickener by adding thickener with high film formation properties. It is also important to choose the most suitable dyestuffs (dyestuffs containing less dispersant, such as liquid type dyestuffs).

In the case of over-drying in 3., strain can be caused between the cloth and the print paste so that the print paste can peel. The ways to prevent this over-drying are:

(a) Adding hygroscopic agents, such as urea, glycerin,
 polyethylene glycol (PEG) etc.

(b) Establishing an appropriate system(heating table, hot air blower etc).

In the case of extreme unevenness in 4., particularly the convexities will easily come off. Print pastes which are most likely to cause the phenomenon shown in Figure 2 tend to have poor fluidity, such as starch-type print pastes. Thus, it is important to add print pastes with appropriate fluidity (sodium alginate, guar gum).

Figure 2. Uneven dyed surface using print paste with bad fluidity.

In the case of using thin cloth (Figure 3), convexities which are just like needles will be created on the back of the cloth. Particularly, when using thin cloth such as georgette or crape, special attention must be paid.

Figure 3. In the case of thin cloth, the backside of the cloth will have convexity.

If print pastes do not penetrate well (in the case of 5.), they cannot stick to the cloth well, therefore, the adhesion level will decrease. In this case, it is necessary to ensure appropriate penetration (the penetration should reach more than 1/2 of the printed layer).

The ways to bring about successful penetration are:

(a) Using thickener with good penetrating properties, i.e. guar gum

(b) Using penetrating agents
(mineral turpentine, octyl alcohol, surfactant etc)

(c) Make sure drying speed is not too fast.

According to 6., it is very important to be careful with printed cloth.

(1) After printing and drying, you need extra strength to detach the cloth from the table. Therefore, the cloth can be elongated because of the extra tension, and then strain will be caused between the cloth and the print pastes. Thus, it will result in cracking and splashing of print paste. To prevent this, the following are recommended:

(a) Detaching the cloth before drying is completely finished.

(b) Providing moisture(it is good to spray water, blow it with cold air or
carry out cover-printing throughout using print pastes with high
viscosity, i.e. CMC.)

(c) Adding hygroscopic agents (glycerin, PEG etc)

(d) Using thickeners with good elasticity

(e) Carrying out dry-air drying or cold-air drying rather than using a
heating table. In the case of using a heating table, a final blowing of
cold air is recommended.

(2) For bringing dried cloth to a steaming factory, it is necessary to roll up the cloth, carry it and spread it at the factory (Figure 4).

Figure 4. Carrying dried cloth. Soft print paste is necessary for "spreading".

For this situation, the print pastes have to be rich in elasticity. Thus, it is important to use thickeners with good elasticity.

(a) Use CMC and guar types.

(b) Maintain the elasticity of the print pastes by providing moisture
in the way shown in (1).

In the case of static electricity in 7., it is important to carry out steaming after slapping the cloth to get rid of the splashes of the print paste since the splashes of the color paste sometimes can be attracted by the cloth due to static.

Finally, according to 8., print paste splashing and cracking can be caused depending on design: particularly with deep shades, line delineation patterns and more white ground. Thus, when using such designs, it is important to plan ahead.

Cases in which chafe marks occur.

Possible causes of chafe marks are listed as follows:

1. Using thickeners with poor film formation
2. 2.Excessive amount of dyestuff, especially when auxiliary and hygroscopic agents are used
3. Too much moisture
4. The types of material
5. Treatment being carried out inappropriately

(1) It is necessary to choose thickeners with strong film formation(e.g. guar gum, CMC etc).

(2) It is important NOT to exceed the recommended amount of dyestuff or its saturation value. Particularly, special attention must be paid to deep shades. It is important NOT to overuse auxiliaries (carriers, dispersants etc) and hygroscopic agents (urea, glycerin etc). It is recommended NOT to add these if possible.

(3) Excessive moisture should be avoided. (4) It is important to take into account that chafe marks can easily be caused depending on the structures of woven fabric. For instance, fabric with a rough surface, a fluffy surface, satin, wool and mohair.

(5)Printed cloth should be treated carefully to prevent chafe marks.