A stretchable mounting board that includes a stretchable substrate having a main surface, a stretchable wiring disposed on the main surface of the stretchable substrate, a mounting electrode section electrically connected to the stretchable wiring, solder electrically connected to the mounting electrode section and including bismuth and tin, and an electronic component electrically connected to the mounting electrode section with the solder interposed therebetween. The mounting electrode section has a first electrode layer on a side thereof facing the stretchable wiring and which includes bismuth and tin, and a second electrode layer on a side thereof facing the solder and which includes bismuth and tin. A concentration of the bismuth in the first electrode layer is lower than a concentration of the bismuth in the second electrode layer.

Devices and methods for encapsulating a portion of a wound dressing with biocompatible coating are disclosed. In some embodiments, a method includes coating a first side of a flexible wound contact layer of the wound dressing with a hydrophobic coating. The first side of the wound contact layer can support a plurality of electronic components. The method can further include coating a second side of the wound contact layer opposite the first side with the hydrophobic coating. The wound contact layer can be formed at least partially from hydrophilic material.

Provided are biphasic compositions including a quantity of a conductive liquid and a plurality of a particulate suspended in the quantity of conductive liquid, wherein there is sufficient wetting between the solid particles and the conductive liquid and wherein the resistance of the compositions are less than the resistance for a bulk conductor when strained as defined by Pouillet's law. Also provided are stretchable circuit board assemblies including the biphasic compositions and methods of using the stretchable circuit board assemblies including the biphasic compositions.

A stretchable wiring board that includes: a stretchable substrate; a first wiring line on the stretchable substrate; an insulating layer overlapping a first part of the first wiring line in a plan view of the stretchable wiring board; and a second wiring line overlapping the first part of the first wiring line in the plan view with the insulating layer interposed therebetween. The insulating layer has at least one first notch, and in the plan view, the at least one first notch does not overlap the first wiring line and overlaps the second wiring line.

The present invention relates to a method for producing a flexible substrate. According to the method of the present invention, a flexible substrate layer can be easily separated from a carrier substrate even without the need for laser or light irradiation so that a device can be prevented from deterioration of reliability and occurrence of defects caused by laser or light irradiation. In addition, according to the method of the present invention, a flexible substrate can be continuously produced in an easier manner based on a roll-to-roll process.

A bulk substrate for stretchable electronics. The bulk substrate is manufactured with a process that forms a soft-elastic region of the bulk substrate. The soft-elastic region includes a strain capacity of greater than or equal to 25% and a first Young's modulus below 10% of a maximum local modulus of the bulk substrate. The process also forms a stiff-elastic region of the bulk substrate. The stiff-elastic region includes a strain capacity of less than or equal to 5% and a second Young's modulus greater than 10% of the maximum local modulus of the bulk substrate.

A closed-loop wearable device or platform integrates sensors, actuators, and microcontroller on board. The device is applied directly to the skin using stretchable epidermal electronics. It can sense a variety of signals from the human body, thus collecting medically relevant information, and can activate delivery of a therapeutic upon detection of an abnormal condition. The therapeutic can be delivered at a personalized dosage and/or with a unique combination of drugs or other agents based on the individual's metabolism as tracked by various sensor modules integrated with the medical device.

A conductive bump electrode structure includes a substrate, an elastic circuit layer, at least two conductive bumps, and an insulating layer. The elastic circuit layer is mounted on the substrate, and includes at least one elastic circuit. The at least two conductive bumps are mounted on the elastic circuit layer, and are electrically connected to each other through the at least one elastic circuit. The insulating layer is mounted on the elastic circuit layer, and includes at least two holes. Since there is a gap between the conductive bumps, the conductive bump electrode structure is easy to be bent and fit body curves of various parts of a user. The elastic circuit can stretch or compress along with the user's movement due to its elasticity, thereby increasing suitability of the conductive bump electrode structure to the human body.

Examples are provided for a flexible circuit element including a flexible insulating support structure, a solid metal trace extending at least partially between a first connector and a second connector on the flexible insulating support structure, and a liquid metal conductor disposed in contact with the solid metal trace in a region of the trace configured to repeatedly flex when installed in a device.

Provided is a self-adhesive sheet including a 4-methyl-1-pentene-based polymer. In the self-adhesive sheet, it is preferable that at least one or more temperatures showing a local maximum value of a loss tangent (tan δ) , which is obtained by dynamic viscoelasticity measurement under conditions of a temperature rising rate of 4° C./min, a frequency of 1.59 Hz, and a strain amount of 0.1%, are present in a range of 10° C. or higher and 100° C. or lower, the local maximum value of the loss tangent is 0.5 or more and 3.5 or less, an arithmetic average roughness Ra on one surface of the self-adhesive sheet is in a range of 0.01 to 10 .Math.m, and a ten-point average roughness Rz is in a range of 0.1 to 50 .Math.m.