A treating composition comprising: a polycarbodiimide; and a silicon-containing compound selected from a cyclic siloxane compound, a silsesquioxane polymer, and a mixture thereof; wherein the cyclic siloxane compound is of Formula: wherein: each R 1 and R 2 is independently a (C1-C4)alkyl; each L 1 and L 2 is independently a single bond, an alkylene, or an alkylene bonded to a group selected from oxy, thio, carbonyl, -NH-, and combinations thereof; each R 3 is independently a linear (C14-C100)alkyl; each R 4 is independently a (C1-C30)alkyl, a (C2-C30)heteroalkyl having at least one oxygen, sulfur, or -NH- group, or a (C1-C30)alkyl substituted with a fluoro, thiol, isocyanato, cyanato, hydroxyl, glycidoxy, or epoxy group; with the proviso that L 1, L 2, and R 4 are selected such that each Si atom is directly bonded to an alkylene or an alkyl (other than R 1 and R 2); m is an integer of at least 2; n is an integer of 0 or above; m + n is an integer of at least 3; and the cyclic siloxane compound is a solid at 25°C; and wherein the silsesquioxane polymer comprises a three-dimensional network of Formula: wherein: each R 1 and R 2 is independently a (C1-C4)alkyl; each L 1 and L 2 is independently a single bond, an alkylene, or an alkylene bonded to a group selected from oxy, thio, carbonyl, -NH-, and combinations thereof; each R 3 is independently a linear (C14-C100)alkyl; each R 4 is independently a (C1-C30)alkyl, a (C2-C30)heteroalkyl having at least one oxygen, sulfur, or -NH- group, or a (C1-C30)alkyl substituted with a fluoro, thiol, isocyanato, cyanato, hydroxyl, glycidoxy, or epoxy group; with the proviso that L 1, L 2, and R 4 are selected such that each Si atom is directly bonded to an alkylene or an alkyl; m is an integer of at least 2; n is an integer of 0 or above; m + n is an integer of at least 3; each oxygen atom at an asterisk (*) is bonded to another Si atom within the three-dimensional network; and the silsesquioxane polymer is a solid at 25°C. a polycarbodiimide; and a silicon-containing compound selected from a cyclic siloxane compound, a silsesquioxane polymer, and a mixture thereof; wherein the cyclic siloxane compound is of Formula: wherein: each R 1 and R 2 is independently a (C1-C4)alkyl; each L 1 and L 2 is independently a single bond, an alkylene, or an alkylene bonded to a group selected from oxy, thio, carbonyl, -NH-, and combinations thereof; each R 3 is independently a linear (C14-C100)alkyl; each R 4 is independently a (C1-C30)alkyl, a (C2-C30)heteroalkyl having at least one oxygen, sulfur, or -NH- group, or a (C1-C30)alkyl substituted with a fluoro, thiol, isocyanato, cyanato, hydroxyl, glycidoxy, or epoxy group; with the proviso that L 1, L 2, and R 4 are selected such that each Si atom is directly bonded to an alkylene or an alkyl (other than R 1 and R 2); m is an integer of at least 2; n is an integer of 0 or above; m + n is an integer of at least 3; and the cyclic siloxane compound is a solid at 25°C; and each R 1 and R 2 is independently a (C1-C4)alkyl; each L 1 and L 2 is independently a single bond, an alkylene, or an alkylene bonded to a group selected from oxy, thio, carbonyl, -NH-, and combinations thereof; each R 3 is independently a linear (C14-C100)alkyl; each R 4 is independently a (C1-C30)alkyl, a (C2-C30)heteroalkyl having at least one oxygen, sulfur, or -NH- group, or a (C1-C30)alkyl substituted with a fluoro, thiol, isocyanato, cyanato, hydroxyl, glycidoxy, or epoxy group; with the proviso that L 1, L 2, and R 4 are selected such that each Si atom is directly bonded to an alkylene or an alkyl (other than R 1 and R 2); m is an integer of at least 2; n is an integer of 0 or above; m + n is an integer of at least 3; and the cyclic siloxane compound is a solid at 25°C; and wherein the silsesquioxane polymer comprises a three-dimensional network of Formula: wherein: each R 1 and R 2 is independently a (C1-C4)alkyl; each L 1 and L 2 is independently a single bond, an alkylene, or an alkylene bonded to a group selected from oxy, thio, carbonyl, -NH-, and combinations thereof; each R 3 is independently a linear (C14-C100)alkyl; each R 4 is independently a (C1-C30)alkyl, a (C2-C30)heteroalkyl having at least one oxygen, sulfur, or -NH- group, or a (C1-C30)alkyl substituted with a fluoro, thiol, isocyanato, cyanato, hydroxyl, glycidoxy, or epoxy group; with the proviso that L 1, L 2, and R 4 are selected such that each Si atom is directly bonded to an alkylene or an alkyl; m is an integer of at least 2; n is an integer of 0 or above; m + n is an integer of at least 3; each oxygen atom at an asterisk (*) is bonded to another Si atom within the three-dimensional network; and the silsesquioxane polymer is a solid at 25°C. each R 1 and R 2 is independently a (C1-C4)alkyl; each L 1 and L 2 is independently a single bond, an alkylene, or an alkylene bonded to a group selected from oxy, thio, carbonyl, -NH-, and combinations thereof; each R 3 is independently a linear (C14-C100)alkyl; each R 4 is independently a (C1-C30)alkyl, a (C2-C30)heteroalkyl having at least one oxygen, sulfur, or -NH- group, or a (C1-C30)alkyl substituted with a fluoro, thiol, isocyanato, cyanato, hydroxyl, glycidoxy, or epoxy group; with the proviso that L 1, L 2, and R 4 are selected such that each Si atom is directly bonded to an alkylene or an alkyl; m is an integer of at least 2; n is an integer of 0 or above; m + n is an integer of at least 3; each oxygen atom at an asterisk (*) is bonded to another Si atom within the three-dimensional network; and the silsesquioxane polymer is a solid at 25°C.