Table 1. The different operating parameters of the wet-spinning system and a qualitative assessment of the appearances of the final products.

Sample denotationa	Parameters of the wet-spinning system				Qualitative observation of appearances compared with The controlb
	Air pressure (bar)	Needle size (μm)	Calcium conc. (w/v%)	Alginate conc. (w/v%)	Fiber size		Fibrous structure
					Larger	Smaller	Compact	Loose
Control	6	150	5.0	1.5
P	3	150	5.0	1.5	++			++
D	6	200	5.0	1.5	+			+
Ca	6	150	0.5	1.5	+		+
A	6	150	5.0	3	similar			+

+, observed; ++, observed in a more significant way than others; ^aAlginate samples are coded according to the variable in the manufacturing process. For example, P is a sample manufactured with an air pressure that was different from the control. ^bThe observations were based on the pictures in Figure 1.