(1) Screen mesh
2-3kg of color paste add-on is necessary for 1m2 of pile fabric (pile lengths: 4-10mm, and polyester mesh which has a large opening-area ratio, approximately 36-60 mesh (the number of cells / inch), is used in order to allow an increased amount of print paste.
For rotary screens, rough mesh, approximately 10-30 mesh, is used.

(2) Squeegee
Using a plate squeegee with rounded or angled cross-section and squeegee-ing by pressing it hard enough to bend leads to more penetration. A roll squeegee (or a metal rod) is more suitable than a plate squeegee for penetration printing on pile fabric. To achieve more penetration with the roll squeegee, the diameter of the roll has to be large. In addition, a magnet roll squeegee (penetration is achieved when the magnet attracts the squeegee and forces the paste through) is applied in P. Zimmer's flat screen and rotary screen. (Figure 2)

Figure 2  P Zimmer's magnet roll method

(3) Viscosity of color paste
In the case of printing cut pile fabric, the most important thing to consider is to let the color paste penetrate till it reaches the roots of the pile. The most appropriate viscosity of color paste is 3,000± 1,000 cps, however, on certain kinds of loop carpet penetration can be achieved even with high viscosity. The viscosity of color paste is determined by the shape, density and length of the pile. Lowering viscosity helps penetration to the roots of the pile but lacks sharpness for the outlines of motifs (penetration and sharpness are inversely related), therefore, the viscosity of color paste should be determined in relation to mechanical printing conditions.

(4) Wet steaming
In the case of printing on carpets and blankets, steam fixing (wet steaming) without drying the color paste right after printing is generally accepted. For woven / knit fabric, color paste will be dried to be fixed after printing in order to increase the sharpness of motif outlines. Color paste which has not been dried does not get fixed and easily moves warpwise. Furthermore, steaming (high temperatures) is good for penetration printing since the viscosity of the color paste will be lowered during the process. In addition, reduction in cost for drying heavy-weight materials will be possible. In the case of using direct dyestuffs, acid dyestuffs, disperse dyestuffs, cationic dyestuffs etc, even though they are non-dried, the wet-steaming process is usually carried out, however, as a matter of fact, the efficiency of dyestuff usage due to hydrolysis will remarkably decrease in the use of reactive dyestuffs, therefore, the steaming process is necessary. (Figure 3)

Figure 3 Penetration of color paste on pile fabric

(5) Stock paste
In consideration of selective conditions (penetrating properties, sharpness, paste removal properties, color development, price, printability, chemical resistance etc) which are the same as general materials would require, locust bean/guar gum types (stable viscosity and less temperature dependency during steaming) are commonly used for cationic, acid and direct dyestuffs. In addition, sodium alginate is suitable for reactive dyestuffs and is also recommended for disperse dyestuffs, rather than using gum type thickeners, because it can be easily removed. In penetration printing with cut pile materials, it is difficult to evaluate the advantage of combinations of thickeners (e.g. a combination of CMC, CMS etc) practiced in general material printing since the color paste is prepared in low viscosities, 2,000-3,000cps. For instance, combining O/W emulsion paste will reduce the solidity of the thickeners within the color paste (advantages such as cost reduction in color paste and improvement in the efficiency of water washing/paste removal can be seen). Furthermore, as continuous printability (transferral property) is improved, higher penetration can be expected depending on the components (oil and emulsifier) of the emulsion. As mineral turpen (mineral oil) is emulsified, O/W emulsion paste will have higher drying efficiency after printing, therefore, it is often used as a color paste for towels.

(6) Chemicals for printing
Chemicals listed in Table 1 are penetrating agents, dye accelerators, leveling agents (an inhibitor for frostiness on hair-tip, or a retardant), a reduction inhibitor and a release agent (improving transferral property, inhibiting paste splashing) and antifoaming agents etc which are considered suitable to be used with dyestuffs.

Table 1 Printing pastes and auxiliaries for pile fabric

Names	Use as	Dyestuff suitability					Types of ion
		Reac- tive	Di- rect	Dis- perse	Cati- onic	Acid
Primogum F-30	Thickening emul- sion paste						A
Primogum F-100	Compounded thickener						A
Primogum C-1	Sodium alginate						A
Primogum T-9	Guar gum	-					N
ECN-11	Mineral thickener						A
Serenasol GKZ	Dyestuff dissolv- ing agent	-		-			-
Resister liquid	Anti-reduction agent						A
Senkasalt Ksconc	Penetrating agent						N
Serenasol FCN-A	Deepener for acryl	-	-	-		-	-
GTP-31	Deepener for polyester	-	-		-	-	N
AOP-21	Penetrating agent for acryl	-	-	-		-	C
EOP-12	Retardant/penetrating agent for acryl	-	-	-		-	C
Senkasalt SP	Anti-frosting agent						A
Senkaemulsyn 300	Softening / leveling of printed layer						N
GTG-01	Solubilizer for alkali discharge	-	-		-	-	N
Senkasalt S-45	Release agent						N
Senkasalt DND	Deepener for nylon	-	-	-	-		A
Printing oil	Antiseptic / antifoaming agent						A
Senka antifoam 4B	Silicon type / antifoaming agent						N

Dyestuff suitability		:	Most applicable		:	Applicable		:	Not applicable
Types of ion	A	:	Anion	C	:	Cation	N	:	Nonion