An ink set for ink-jet recording includes two or more inks each of which contains water, a coloring agent, and a water-soluble organic solvent. Furthermore, because member devices are authenticated using the common secret information when contents are to be used, and contents are only delivered if the authentication is successful, member devices that do not hold the common secret information can be prevented from using contents. The engineered binder comprises a siliceous material and at least one organic component selected from: at least one type of wood pulp; at least one species of cellulose fiber; and combinations thereof. The first and the second electrode down-leads are parallel to each other.