Abstract: An over-current protection device includes an electrode layer and a heat-sensitive layer. The heat-sensitive layer includes a polymer matrix and a conductive filler. The polymer matrix includes a polyolefin-based polymer and an olefin-acrylate copolymer. The polyolefin-based polymer is represented by a formula (I): ?wherein R1 and R2 are selected from the group consisting of CH3, C2H5, and C3H7. The olefin-acrylate copolymer is represented by a formula (II): ?wherein R is selected from the group consisting of COOCH3, COOC2H5, and COOC4H9.

Abstract: An over-current protection device includes an electrode layer and a heat-sensitive layer. The heat-sensitive layer exhibits a positive temperature coefficient (PTC) characteristic, and is laminated between a top metal layer and a bottom metal layer of the electrode layer. The heat-sensitive layer includes a polymer matrix and a conductive filler. The polymer matrix includes a fluoropolymer. The fluoropolymer has a plurality of spherulites, and the fractal dimension of each spherulite is lower than 12.

Abstract: An over-current protection device includes an electrode layer and a heat-sensitive layer. The heat-sensitive layer exhibits a positive temperature coefficient (PTC) characteristic, and is laminated between a top metal layer and a bottom metal layer of the electrode layer. The heat-sensitive layer includes a polymer matrix and a conductive filler. The polymer matrix includes a first fluoropolymer and a second fluoropolymer. The weight average molecular weight of the second fluoropolymer ranges from 630000 g/mol to 1100000 g/mol. The conductive filler is dispersed in the polymer matrix, thereby forming an electrically conductive path in the heat-sensitive layer.

Abstract: An over-current protection device includes an electrode layer and a heat-sensitive layer. The heat-sensitive layer exhibits a positive temperature coefficient (PTC) characteristic, and is laminated between a top metal layer and a bottom metal layer of the electrode layer. The heat-sensitive layer includes a polymer matrix and a conductive filler. The polymer matrix includes a first fluoropolymer and a second fluoropolymer. The first fluoropolymer has a first volume and a first melt flow index, and the second fluoropolymer has a second volume and a second melt flow index. The second melt flow index ranges from 0.4 g/10 min to 0.7 g/10 min and is lower than the first melt flow index, and a volume ratio by dividing the second volume by the first volume ranges from 0.4 to 0.6.

Abstract: An over-current protection device includes an electrode layer and a heat-sensitive layer. The heat-sensitive layer exhibits a positive temperature coefficient (PTC) characteristic, and is laminated between a top metal layer and a bottom metal layer of the electrode layer. The heat-sensitive layer includes a polymer matrix and a conductive filler. The polymer matrix includes a first fluoropolymer and a second fluoropolymer. The first fluoropolymer includes a first melting point, and the second fluoropolymer has a second melting point lower than the first melting point. The difference between the first melting point and the second melting point is smaller than 14° C. The second fluoropolymer has a second melt flow index ranging from 0.4 g/10 min to 0.7 g/10 min.

Abstract: An over-current protection device includes an electrode layer and a heat-sensitive layer. The heat-sensitive layer contacts a top metal layer and a bottom metal layer of the electrode layer, and is laminated therebetween. In addition, the heat-sensitive layer exhibits a positive temperature coefficient (PTC) characteristic and includes a polymer matrix and a conductive filler. The polymer matrix includes a first fluoropolymer, by which the over-current protection device has a starting jump temperature of resistance ranging from 184° C. to 192° C. The conductive filler includes carbon black and a metal compound, thereby forming an electrically conductive path in the heat-sensitive layer.

Abstract: An over-current protection device includes an electrode layer and a heat-sensitive layer. The heat-sensitive layer exhibits a positive temperature coefficient (PTC) characteristic, and is laminated between a top metal layer and a bottom metal layer of the electrode layer. The heat-sensitive layer includes a polymer matrix and a conductive filler. The polymer matrix includes a fluorine-containing copolymer, and its melting point ranges from 210° C. to 240° C. The conductive filler consists of carbon black solely, and is used to form an electrically conductive path in the heat-sensitive layer. In addition, the over-current protection device has a resistance-jump ratio ranging from 1.2 to 1.3 between 40° C. and 130° C.

Abstract: An over-current protection device includes a heat-sensitive layer and an electrode layer. The electrode layer includes a top metal layer and a bottom metal layer, and the heat-sensitive layer attached therebetween. The heat-sensitive layer exhibits a positive temperature coefficient (PTC) characteristic and includes a polymer matrix and a conductive filler. The polymer matrix includes a polyolefin-based homopolymer and a polyolefin-based copolymer. The polyolefin-based homopolymer has a first coefficient of thermal expansion (CTE), and the polyolefin-based copolymer has a second CTE lower than the first CTE. The polyolefin-based homopolymer and the polyolefin-based copolymer together form an interpenetrating polymer network (IPN).

Abstract: An over-current protection device includes first and second electrode layers and a PTC material layer laminated therebetween. The PTC material layer includes a polymer matrix, a conductive filler, and a titanium-containing dielectric filler. The polymer matrix has a fluoropolymer. The titanium-containing dielectric filler has a compound represented by a general formula of MTiO3, wherein the M represents transition metal or alkaline earth metal. The total volume of the PTC material layer is calculated as 100%, and the titanium-containing dielectric filler accounts to for 5-15% by volume of the PTC material layer.

Abstract: An over-current protection device includes first and second electrode layers and a PTC material layer laminated therebetween. The PTC material layer includes a polymer matrix, and a conductive filler. The polymer matrix has a fluoropolymer. The total volume of the PTC material layer is calculated as 100%, and the fluoropolymer accounts for 47-62% by volume of the PTC material layer. The fluoropolymer has a melt viscosity higher than 3000 Pa·s.

Abstract: An over-current protection device includes a first metal layer, a second metal layer and a heat-sensitive layer laminated therebetween. The heat-sensitive layer exhibits a positive temperature coefficient (PTC) characteristic and includes a polymer matrix and a first conductive filler. The polymer matrix includes a polyolefin-based polymer and a fluoropolymer. The fluoropolymer has a melt flow index higher than 1.9 g/10 min, and the polyolefin-based polymer and the fluoropolymer together form an interpenetrating polymer network (IPN). The first conductive filler has a metal-ceramic compound dispersed in the polymer matrix.

Abstract: An over-current protection device includes a first metal layer, a second metal layer and a heat-sensitive layer laminated therebetween. The heat-sensitive layer exhibits a positive temperature coefficient (PTC) characteristic and includes a first polymer and a conductive filler. The first polymer consists of polyvinylidene difluoride (PVDF), and PVDF exists in different phases such as ?-PVDF, ?-PVDF and ?-PVDF. The total amount of ?-PVDF, ?-PVDF and ?-PVDF is calculated as 100%, and the amount of ?-PVDF accounts for 33% to 42%.

Abstract: An over-current protection device includes a first metal layer, a second metal layer and a heat-sensitive layer laminated therebetween. The heat-sensitive layer exhibits a positive temperature coefficient (PTC) characteristic and includes a first polymer and a conductive filler. The first polymer consists of polyvinylidene difluoride (PVDF), and PVDF exists in different phases such as ?-PVDF, ?-PVDF and ?-PVDF. The total amount of ?-PVDF, ?-PVDF and ?-PVDF is calculated as 100%, and the amount of ?-PVDF accounts for 48% to 55%. The conductive filler has a metal-ceramic compound.

Abstract: A circuit protection device includes a first temperature sensitive resistor, a second temperature sensitive resistor, an electrically insulating multilayer, a first and second electrode layer, and at least one external electrode. The first temperature sensitive resistor and the second temperature sensitive resistor are electrically connected in parallel, and have a first upper electrically conductive layer and a second lower electrically conductive layer, respectively. The electrically insulating multilayer includes an upper insulating layer, a middle insulating layer, and a lower insulating layer. The upper insulating layer is between the first upper electrically conductive layer and the first electrode layer. The middle layer is laminated between the first temperature sensitive resistor and the second temperature sensitive resistor. The lower insulating layer is between the second lower electrically conductive layer and the second electrode layer.

Abstract: An over-current protection device includes first and second electrode layers and a PTC material layer laminated therebetween. The PTC material layer includes a polymer matrix, a conductive filler, and a titanium-containing dielectric filler. The polymer matrix has a fluoropolymer. The titanium-containing dielectric filler has a compound represented by a general formula of MTiO3, wherein the M represents transition metal or alkaline earth metal. The total volume of the PTC material layer is calculated as 100%, and the titanium-containing dielectric filler accounts to for 5-15% by volume of the PTC material layer.

Abstract: An over-current protection device comprises first and second electrode layers and a PTC material layer laminated therebetween. The PTC material layer includes a polymer matrix, a conductive filler and a titanium-containing inner filler. The polymer matrix has a fluorine-free polyolefin-based polymer. The titanium-containing inner filler has a compound represented by a general formula of MTiO3, wherein the M represents transition metal or alkaline earth metal. The total volume of the PTC material layer is calculated as 100%, and the titanium-containing inner filler accounts for 1-9% by volume of the PTC material layer.