Abstract: An image forming apparatus includes an apparatus body, a developer container, a data recording medium, a contact terminal, a detector, and control circuitry. The developer container is detachably attached in the apparatus body. The data recording medium is on the developer container. The contact terminal is disposed in the apparatus body and contacts the data recording medium. The detector detects a communication failure between the data recording medium and the apparatus body. The control circuitry executes a control mode to vibrate the data recording medium when the detector detects the communication failure.

Abstract: A handle structure of a power tool comprises a handle portion continuously formed with the main body of the power tool and a gutter-like soft grip for covering the handle portion, the soft grip having two first engaging projections on its inner surface and two second engaging pieces provided on each edge of the soft grip, the handle portion having two first receiving recesses provided on an arched receiving surface for receiving the soft grip to detachably engage the two first engaging projections and the second receiving grooves provided between the receiving surface and an outer front side surface of the handle portion for detachably receiving the second engaging pieces, the first engaging recesses and the second engaging grooves being completely separated from a space provided in the front portion of the handle portion for accommodating wires and the like.

Abstract: This invention provides a process for preparing cyclic phosphonitrilic chloride oligomers characterized by the combination of:(I) The first step of reacting phosphorus pentachloride with ammonium chloride in an inert organic solvent in the presence of a catalyst comprising at least one of (a) chlorides of bivalent metals and (b) organic acid salts of bivalent metals, and distilling off the solvent from the resulting reaction mixture to obtain a reaction product consisting essentially of cyclic phosphonitrilic chloride oligomers, and(II) the second step of contacting a solution of the reaction product in at least one solvent selected from the group consisting of aliphatic hydrocarbons and ethers with water at a temperature of about 40.degree. to about 100.degree. C.