Dyeing of Pineapple Leaf Fibers Using Various Natural Dye Extracts and Mordants

Figures & data

Figure 1. Schematic diagram of dyeing procedure.

Figure 2. Visual aspect of PALF (a) before and after bleaching (b) 5%, (c) 10%, and (d) 15% H₂O₂.

Figure 3. The effect of H₂O₂ concentration (%owf) on whiteness index and yellowness index of bleached PALF.

Figure 4. Plot of color coordinates for bleached PALF.

Table 1. The effect of H₂O₂ concentration (%owf) on color coordinates of bleached PALF.

H2O2 (%owf)	Color coordinates of bleached PALF
	$L^{\ast }$	$a^{\ast }$	$b^{\ast }$	$\mathrm{\Delta }\mathit{E}$	Color obtained
Control	64.34	0.51	17.39	-
5	78.47	−0.33	17.34	14.15
10	80.08	−0.57	16.1	15.83
15	84.95	−1.17	14.42	20.89

Figure 5. The effect of H₂O₂ concentration (%owf) on weight loss of bleached PALF.

Figure 6. The effect of H₂O₂ concentration (%owf) on linear density of bleached PALF.

Table 2. The effect of H₂O₂ concentration (%owf) on mechanical properties of bleached PALF.

H2O2 (%owf)	Breaking force (cN)	Breaking tenacity (cN/tex)	Elongation at break (%)
Control	264.01 ± 7.81	31.06 ± 0.74	6.67 ± 0.30
5	181.25 ± 4.55	28.87 ± 0.81	5.51 ± 0.21
10	168.18 ± 3.24	27.86 ± 1.03	4.20 ± 0.25
15	134.24 ± 4.73	23.24 ± 1.21	3.84 ± 0.29

Figure 7. The chemical structures of the coloring agents in the plant extracts (a) turmeric, (b) diospyrol, (c) laccaic acid a and B, and (d) brazilin and brazilein.

Figure 8. The color strength of dyed PALF.

Figure 9. Plot of color coordinates for dyed PALF.

Table 3. Color coordinate values of dyed PALF with extracts of turmeric powders, ebony fruit, lac, and sappan wood.

Dyes	Mordants	Color coordinates of dyed PALF
		${\mathrm{L}}^{\ast }$	${\mathrm{a}}^{\ast }$	${\mathrm{b}}^{\ast }$	$\mathrm{\Delta }\mathrm{E}$	Color obtained
Turmeric	Unmordanted	50.33	17.01	61.78	-
	Salt	56.07	16.20	71.69	11.48
	Alum	51.65	19.85	74.22	12.83
	Lime	54.14	15.72	63.24	4.28
Ebony	Unmordanted	46.15	3.29	13.60	-
	Salt	46.29	3.21	15.05	1.72
	Alum	47.92	3.36	13.53	1.77
	Lime	46.42	3.52	13.33	0.45
Lac	Unmordanted	40.29	18.30	4.80	-
	Salt	38.20	16.31	5.95	3.11
	Alum	45.92	19.99	6.61	6.15
	Lime	55.20	13.06	13.92	18.25
Sappan	Unmordanted	42.43	20.42	23.23	-
	Salt	49.03	15.94	28.89	9.78
	Alum	33.57	33.18	36.75	20.59
	Lime	52.36	17.82	33.44	14.48

Figure 10. Schematic representation of interaction of PALF, metal, and dye; (a) turmeric, (b) ebony, (c) lac, and (d) sappan (when M^x+ = mordant Al³⁺, Ca²⁺, Na⁺).

Table 4. Fastness properties of dyed PALF with extracts of turmeric powders, ebony fruit, lac, and sappan wood.

Dyes	Mordants	Light	Washing		Perspiration
					Acidic		Alkaline
			CC	CS	CC	CS	CC	CS
Turmeric	Unmordanted	3	4	3–4	5	4–5	5	5
	Salt	3–4	4	3–4	4	4	5	4
	Alum	4	4	4	4–5	5	5	4–5
	Lime	4	4	4	4	4	4–5	4–5
Ebony	Unmordanted	5	4–5	5	5	5	5	5
	Salt	5	5	5	5	5	5	5
	Alum	5	5	5	5	5	5	5
	Lime	5	4–5	5	5	5	5	5
Lac	Unmordanted	2	1–2	4–5	5	3	5	4–5
	Salt	2–3	2	4–5	5	4–5	4–5	4–5
	Alum	2–3	2–3	4–5	3–4	4	3	5
	Lime	2	2	4–5	5	4–5	5	5
Sappan	Unmordanted	3	3	4–5	3–4	3–4	4	3–4
	Salt	3–4	3–4	4–5	2–3	4	2–3	2–3
	Alum	4–5	4	4–5	2–3	3	3	4–5
	Lime	4	3–4	4–5	2–3	3–4	3	2

CC = color change; CS = color staining on cotton.

Figure 11. FTIR spectra of dyed PALF; (a) turmeric, (b) ebony, (c) lac, and (d) sappan (when A: bleached, B: dyed, C: salt mordanted-dyed, D: alum mordanted-dyed, E: lime mordanted-dyed).