Hybrid nanogels and their roles in eliminating soot stains from historical paper manuscripts

Heritage Science

Table 1 The results of color change for the aged soot stained paper, treated paper and aged treated paper samples with different prepared nanogels

Samples	L	a	b	ΔE	L	a	b	ΔE
Aged stained sample before treatment	48.80	− 0.71	2.23	–	48.80	− 0.71	2.23	–
Low-viscosity nanogel					High-viscosity nanogel
TiO₂/carbopol hybrid nanogel
Treated sample before aging	55.49	− 0.40	1.42	6.75E ± 0.025	56.41	− 1.00	0.03	7.93E ± 0.03
Treated sample after aging	55.39	− 0.15	3.39	6.71E ± 0.02	55.49	− 0.91	0.56	6.90F ± 0.025
ZnO/carbopol hybrid nanogel
Treated sample before aging	66.60	0.34	3.89	17.91A ± 0.02	74.94	0.21	3.29	26.17A ± 0.025
Treated sample after aging	65.63	0.09	4.35	16.97B ± 0.125	71.27	0.13	3.89	22.55B ± 0.03
Fe₃O₄/carbopol hybrid nanogel
Treated sample before aging	65.14	0.23	3.79	16.44C ± 0.03	66.51	0.05	3.66	17.78C ± 0.02
Treated sample after aging	63.53	0.24	4.30	14.91D ± 0.02	66.26	− 0.08	2.79	17.47D ± 0.025
p-value				< 0.0001				< 0.0001
LSD 0.05				0.098				0.0465

Means with the same letter within the same column for ΔE are not significantly different according to LSD at 0.05 level of probability