2.3. Characterization of coated paperBefore their characterization, all coated papers were condi-tioned at 23 ± 1 °C and 50 ± 5% RH for 3 days following the TAPPIT402 om-93 standard. The grammage was determined in accor-dance with the ISO 536 standard, using a Metter PC 220 analyticalbalance (±1 mg). The air permeability was measured following theISO 5636/3:1992 standard using a model 114 Lorentzen & WettreBendtsenÒTester. The tensile index was determined using a model65-F Lorentzen & Wettre Alwetron TH1 tester.