Hot melt processable adhesive compositions to mask electronic components include at least one block copolymer, at least one tackifying resin, at least one semi-crystalline polyolefin polymer, at least one plasticizer, and at least one anti-oxidant. The adhesive composition is a hot melt processable pressure sensitive adhesive composition that is thermally stable, such that the composition when disposed on a surface withstands heating to 260° C. without degradation or flowing, remains optically transparent, and after heating to 260° C. remains cleanly removable.

Systems and methods describe herein provide a solution to the technical problem of creating a wearable electronic devices. In particular, these systems and methods enable electrical and mechanical attachment of stretchable or flexible electronics to fabric. A stretchable or flexible electronic platform is bonded to fabric using a double-sided fabric adhesive, and conductive adhesive is used to join pads on the electronic platform to corresponding electrical leads on the fabric. An additional waterproofing material may be used over and beneath the electronic platform to provide a water-resistant or waterproof device This stretchable or flexible electronic platform integration process allows the platform to bend and move with the fabric while protecting the conductive connections. By using flexible and stretchable conductive leads and adhesives, the platform is more flexible and stretchable than traditional rigid electronics enclosures.

A printed circuit board includes: a first insulating layer; a first wiring layer at least partially buried in the first insulating layer; a second insulating layer disposed on an upper surface of the first insulating layer; a second wiring layer at least partially buried in the second insulating layer; and a cavity penetrating through the second insulating layer and a portion of the first insulating layer and exposing a portion of the upper surface of the first insulating layer as a bottom surface of the cavity. The first wiring layer includes a wiring pattern at least partially exposed from the first insulating layer by the cavity, an upper surface of the wiring pattern has a step structure with the upper surface of the first insulating layer exposed by the cavity, and a lower surface of the wiring pattern is coplanar with a lower surface of the first insulating layer.

A method of manufacturing a printed board, the method comprising: a first step of preparing a laminate having a base member in which a plurality of layers of glass cloths and a plurality of resin layers are alternately laminated, a first metal layer attached to one surface of the base member, and a second metal layer attached an opposite surface of the base member; a second step of forming a protective layer removable with a predetermined solvent on each of the first metal layer and the second metal layer; and a third step of irradiating the laminate on which the protective layer is formed with a laser beam to thereby form a through-hole penetrating in a thickness direction of the laminate.

A printed circuit board includes: a first insulating layer; a first wiring layer at least partially buried in the first insulating layer; a second insulating layer disposed on an upper surface of the first insulating layer; a second wiring layer at least partially buried in the second insulating layer; and a cavity penetrating through the second insulating layer and a portion of the first insulating layer and exposing a portion of the upper surface of the first insulating layer as a bottom surface of the cavity. The first wiring layer includes a wiring pattern at least partially exposed from the first insulating layer by the cavity, an upper surface of the wiring pattern has a step structure with the upper surface of the first insulating layer exposed by the cavity, and a lower surface of the wiring pattern is coplanar with a lower surface of the first insulating layer.

A wiring circuit board assembly sheet is partitioned by a product region in which a plurality of wiring circuit boards serving as products are disposed in alignment and a margin region surrounding the product region with the margin region having a first area adjacent to the product region and a second area located at the opposite side of the product region with respect to the first area. The wiring circuit board assembly sheet includes a dummy wiring circuit board disposed in at least a portion of the first area and smaller than the wiring circuit board.

A circuit board assembly includes a flexible circuit board including a first surface, a second surface opposite to the first surface, sensing pads on the first surface, and a connector on the second surface, a first liner which includes a first rear surface covering a portion of the first surface and a first top surface that is opposite to the first rear surface and in which a first opening passing through the first rear surface from the first top surface is defined, a second liner which includes a second rear surface covering a portion of the second surface and a second top surface that is opposite to the second rear surface and in which a second opening passing through the second rear surface from the second top surface is defined. Each of the first and second openings is spaced apart from the flexible circuit board in a plan view.

A method for treating a substrate having millimeter and/or micrometer and/or nanometer structures. The method includes applying at least one protective material to the structures, wherein the at least one protective material can be dissolved in a solvent, and the structures are produced by an imprinting process.

A pressure-sensitive adhesive sheet-including wiring circuit board includes a wiring circuit board including a base insulating layer, a conductive layer disposed on a one-side surface in a thickness direction of the base insulating layer, and a cover insulating layer disposed on the one-side surface in the thickness direction of the base insulating layer so as to cover the conductive layer, and a pressure-sensitive adhesive sheet disposed on the surface of either one side or the other side in the thickness direction of the wiring circuit board.

A method for manufacturing a circuit board with a small size a communication unit comprising a radio frequency (RF) component, an antenna, and an encapsulation layer. The RF component is embedded in the encapsulation layer, the antenna is positioned on the encapsulation layer and electrically connected to the RF component. A rigid substrate is formed on a flexible substrate, and a receiving groove is defined in the rigid substrate to expose the flexible substrate. The communication unit is in the receiving groove, thus causing connection between the RF component and the flexible substrate, thereby the circuit board is formed.