A substrate coated with a resistive composite comprising: at least one resin; at least one carbon black having a surface hydrophobically modified with at least one organic group, the at least one organic group having a molecular weight of 4000 or less and comprising the formula -X -, wherein X is arylene covalently attached to the at least one carbon black and G is a substituent of X comprising at least one group selected from alkyls, carboxylic acid esters, amides, alcoxyls, ethers, ketones, acyls, and halides, -X - is nonionic; and wherein: the resistive composite has a volume resistivity, R v, determined according to ASTM D257-93, at a relative volume fraction, X CB, of the at least one carbon black in the composite, where R v is at least 10 6 ohm-cm; and log R v has a substantially linear relationship with X CB when X CB is varied from 0.1 to 0.5, wherein the substantially linear relationship has a goodness of fit value (R 2) of at least 0.8, and wherein the substantially linear relationship is defined as log R v being directly proportional to - m· X CB, wherein m is greater than 0 and no more than 15, wherein the coated substrate is selected from a charge roller of an electrostatic image forming apparatus, a transfer roller or belt of an electrostatic image forming apparatus, and a developer-carrying roller for carrying a developer layer thereon positioned in a toner cartridge. at least one resin; at least one carbon black having a surface hydrophobically modified with at least one organic group, the at least one organic group having a molecular weight of 4000 or less and comprising the formula -X -, wherein X is arylene covalently attached to the at least one carbon black and G is a substituent of X comprising at least one group selected from alkyls, carboxylic acid esters, amides, alcoxyls, ethers, ketones, acyls, and halides, -X - is nonionic; and wherein: the resistive composite has a volume resistivity, R v, determined according to ASTM D257-93, at a relative volume fraction, X CB, of the at least one carbon black in the composite, where R v is at least 10 6 ohm-cm; and log R v has a substantially linear relationship with X CB when X CB is varied from 0.1 to 0.5, wherein the substantially linear relationship has a goodness of fit value (R 2) of at least 0.8, and wherein the substantially linear relationship is defined as log R v being directly proportional to - m· X CB, wherein m is greater than 0 and no more than 15, wherein the coated substrate is selected from a charge roller of an electrostatic image forming apparatus, a transfer roller or belt of an electrostatic image forming apparatus, and a developer-carrying roller for carrying a developer layer thereon positioned in a toner cartridge. the resistive composite has a volume resistivity, R v, determined according to ASTM D257-93, at a relative volume fraction, X CB, of the at least one carbon black in the composite, where R v is at least 10 6 ohm-cm; and log R v has a substantially linear relationship with X CB when X CB is varied from 0.1 to 0.5, wherein the substantially linear relationship has a goodness of fit value (R 2) of at least 0.8, and wherein the substantially linear relationship is defined as log R v being directly proportional to - m· X CB, wherein m is greater than 0 and no more than 15, wherein the coated substrate is selected from a charge roller of an electrostatic image forming apparatus, a transfer roller or belt of an electrostatic image forming apparatus, and a developer-carrying roller for carrying a developer layer thereon positioned in a toner cartridge.