Newly Developed Nano-Calcium Carbonate and Nano-Calcium Propanoate for the Deacidification of Library and Archival Materials

Table 2

Treatments of laboratory paper samples with calcium propanoate in ethanol.

pH before treatment	pH after treatment
Control paper: 5.4 ± 0.1	Control paper: 8.9 ± 0.1
Acidic paper: 4.9 ± 0.1	Acidic paper: 8.3 ± 0.1
Colour coordinates before treatment	Colour coordinates after treatment
Control paper:	Control paper:
L = 97.15 ± 0.10	L = 97.01 ± 0.08
a = −0.42 ± 0.03	a = −0.48 ± 0.02
b = +0.68 ± 0.06	b = +0.69 ± 0.05
Acidic paper:	Acidic paper:
L = 96.31 ± 0.11	L = 96.31 ± 0.11
a = −0.80 ± 0.03	a = −0.77 ± 0.03
b = +2.11 ± 0.09	b = +1.98 ± 0.07