A resistor includes a resistive element, an insulation plate, a protective film, and a pair of electrodes. The resistive element includes a first face and a second face arranged to face in opposite directions in a thickness direction. The insulation plate is on the first face, and the protective film on the second face. The electrodes are spaced apart in a first direction perpendicular to the thickness direction, and held in contact with the resistive element. Each electrode includes a bottom portion opposite to the insulation plate with respect to the resistive element in the thickness direction. Each bottom portion overlaps with a part of the protective film as viewed in the thickness direction. The resistor further includes a pair of intermediate layers spaced apart in the first direction. The intermediate layers are formed of a material electrically conductive and containing a synthetic resin. Each intermediate layer includes a cover portion covering a part of the protective film. The cover portion of each intermediate layer is disposed between the protective film and the bottom portion of one of the electrodes.

A resistor component includes a substrate having a first surface and a second surface, opposing each other; an external electrode disposed outside of the substrate; a resistive layer disposed on the first surface of the substrate, connected to the external electrode, and including an alloy of a first metal and a second metal; and a first protective layer disposed on the resistive layer and including any one of the first and second metals.

A chip resistor includes a substrate, a resistor layer, a first conductive layer, an insulating layer, a second conductive layer, a third conductive layer, and a fourth conductive layer. The first conductive layer is electrically connected to the resistor layer. The insulating layer covers the resistor layer and the first conductive layer. The second conductive layer covers the first conductive layer and the insulating layer. The third conductive layer covers the second conductive layer and the insulating layer. The fourth conductive layer covers the second conductive layer and the third conductive layer. Bonding strength between the third and fourth conductive layer is stronger than that between the second and fourth conductive layer.

The present invention is provided with a base electrode layer forming step of forming a base electrode layer on both surfaces of a thermistor wafer formed of a thermistor material, a chip forming step of obtaining a thermistor chip with a base electrode layer by cutting the thermistor wafer to form chips, a protective film forming step of forming a protective film formed of an oxide on an entire surface of the thermistor chip with a base electrode layer, a cover electrode layer forming step of forming a cover electrode layer by applying and sintering a conductive paste on an end surface of the thermistor chip with a base electrode layer, and a conduction heat treatment step of performing a heat treatment such that the base electrode layer and the cover electrode layer are electrically conductive, in which the electrode portion is formed.

The present invention is provided with a base electrode layer forming step of forming a base electrode layer on both surfaces of a thermistor wafer formed of a thermistor material, a chip forming step of obtaining a thermistor chip with a base electrode layer by cutting the thermistor wafer to form chips, a protective film forming step of forming a protective film formed of an oxide on an entire surface of the thermistor chip with a base electrode layer, a cover electrode layer forming step of forming a cover electrode layer by applying and sintering a conductive paste on an end surface of the thermistor chip with a base electrode layer, and a conduction heat treatment step of performing a heat treatment such that the base electrode layer and the cover electrode layer are electrically conductive, in which the electrode portion is formed.

A chip resistor includes: an insulating substrate; a resistor portion disposed on one surface of the insulating substrate and including a plurality of resistor bodies spaced apart from each other and a plurality of internal electrodes connecting the plurality of resistor bodies to each other; and a first external electrode and a second external electrode disposed on the one surface of the insulating substrate to be spaced apart from each other and respectively connected to the resistor portion, wherein each of the plurality of resistor bodies has a first end adjacent to the first external electrode and a second end opposing the first end and adjacent to the second external electrode, and each of the first end and the second end of each of the plurality of resistor bodies is connected to one of the plurality of internal electrodes, the first external electrode, or the second external electrode.

A chip resistor includes: an insulating substrate; a resistor portion disposed on one surface of the insulating substrate and including a plurality of resistor bodies spaced apart from each other and a plurality of internal electrodes connecting the plurality of resistor bodies to each other; and a first external electrode and a second external electrode disposed on the one surface of the insulating substrate to be spaced apart from each other and respectively connected to the resistor portion, wherein each of the plurality of resistor bodies has a first end adjacent to the first external electrode and a second end opposing the first end and adjacent to the second external electrode, and each of the first end and the second end of each of the plurality of resistor bodies is connected to one of the plurality of internal electrodes, the first external electrode, or the second external electrode.

A surface-mounted polymer PTC overcurrent protection element having a small package size, comprising a PTC chip, an insulating layer (30), end electrodes (41, 42), and at least one conductive member (60). A dividing gap is designed on a first conductive electrode (21) to form first and second conductive areas (211, 212); the conductive member (60) is arranged at the edge or at least a corner of the first conductive area (211) side of the PTC chip, is used for conducting the first conductive area (211) and a second conductive electrode (22) on the PTC chip, and is not in contact with the end electrodes (41, 42); the main portion comprised in the dividing gap (70) of the first conductive electrode (21) is parallel to the longitudinal direction of the first end electrode (41) and the second end electrode (42). Also provided is a preparation method for the protection element. Thus, the miniaturized overcurrent protection element can satisfy the current PCB process to achieve requirements of mass production. It is convenient to design an overcurrent protection element resistance scheme, and reduce adjustment of a PTC core material formulation.

The present invention provides an apparatus having a protecting element for protecting the apparatus in an emergency, wherein the protecting element is a polymer PTC element, the polymer PTC element has a polymer PTC member, and the polymer PTC member is formed from a polymer composition containing a polyvinylidene fluoride as a main component.

The present invention is provided with a base electrode layer forming step of forming a base electrode layer on both surfaces of a thermistor wafer formed of a thermistor material, a chip forming step of obtaining a thermistor chip with a base electrode layer by cutting the thermistor wafer to form chips, a protective film forming step of forming a protective film formed of an oxide on an entire surface of the thermistor chip with a base electrode layer, a cover electrode layer forming step of forming a cover electrode layer by applying and sintering a conductive paste on an end surface of the thermistor chip with a base electrode layer, and a conduction heat treatment step of performing a heat treatment such that the base electrode layer and the cover electrode layer are electrically conductive, in which the electrode portion is formed.