The invention provides a curable composition for inkjet, a cured product, and a flexible printed circuit board. The curable composition for inkjet includes a soluble polyimide resin, a photocurable acrylate compound, a photopolymerization initiator, and a thermosetting resin. The curable composition for inkjet has excellent flexibility, and has a withstand voltage of greater than 2 kV even when the thickness is less than 20 μm.

An electronic device may be provided with a conductive housing sidewall and a phased antenna array that conveys radio-frequency signals at frequencies greater than 10 GHz. Each antenna in the array may radiate through a respective aperture in the sidewall. The antenna module may include a folded flexible printed circuit having a first portion and a second portion that extends from an end of the first portion and that is folded with respect to the first portion. The antennas in the phased antenna array may have antenna resonating elements that are distributed between the first and second portions. Forming the antenna module from a folded flexible printed circuit in this way may serve to minimize the thickness of the antenna module, thereby allowing the antenna module to fit between a ledge of the sidewall and a rear housing wall without occupying excessive space within the device.

An apparatus is disclosed for transferring a pattern of a composition containing particles of an electrically conductive material and a thermally activated adhesive from a surface of a flexible web to a surface of a substrate. The apparatus comprises: respective drive mechanisms for advancing the web and the substrate to a nip through which the web and the substrate pass at the same time and where a pressure roller acts to press the surfaces of the web and the substrate against one another, a heating station for heating at least one of the web and the substrate prior to, or during, passage through the nip, to a temperature at which the adhesive in the composition is activated, a cooling station for cooling the web after passage through the nip, and a separating device for peeling the web away from the substrate after passage through the cooling station, to leave the pattern of composition adhered to the surface of the substrate.

A printed circuit board according to an embodiment includes a first insulating layer; a first circuit pattern disposed on a lower surface or inside the first insulating layer; a second circuit pattern disposed on an upper surface of the first insulating layer; a second insulating layer disposed on the upper surface of the first insulating layer and surrounding the second circuit pattern; and a protective layer disposed on an upper surface of the second insulating layer, wherein the second insulating layer has at least one recess formed on its upper surface, and wherein the protective layer is disposed in the recess formed on the upper surface of the second insulating layer.

A diamine monomer compound with a structural formula of

##STR00001##

wherein n.sub.1 is an integer greater than 1, forms the basis of a dielectric material with reduced dielectric losses for improved signals transmission. A method for preparing the compound, a polyimide resin made from the compound, a flexible film, and an electronic device including the polyimide resin are also disclosed. The compound has a long but flexible even numbered carbon chain and a liquid crystal unit structure. The reduced regularity and rigidity of the molecular chain make the polyimide resin convenient for film-forming. Dimensional stability is improved, the coefficient of thermal expansion of the materials is reduced, and the materials have good mechanical and thermal properties, the electron loss factor and coefficient of thermal expansion of the materials being reduced.

This photosensitive resin composition comprises: a photosensitive prepolymer having a carboxyl group and an ethylenically unsaturated group; a photopolymerization initiator; a thermosetting agent; and a pigment. The thermosetting agent is a polycarbodiimide compound represented by formula (1), in which a carbodiimide group is protected by an amino group that dissociates at temperatures of 80□ or greater. The polycarbodiimide compound has a weight average molecular weight of 300-3000, and a carbodiimide equivalent weight of 150-600. When formed into a film having a dry film thickness of 10-40 μm, the maximum value of the transmittance of the photosensitive resin composition is at least 7% for the transmission spectrum of at least some of the wavelength from 350-430 nm. (In formula (1), R.sup.1, R.sup.2, X.sup.1, X.sup.2, and n are as defined in the description.)

A transmission circuit includes a first semiconductor device, a second semiconductor device, a first signal line, a second signal line, a third signal line, and a ground line. A differential signal is composed of a first signal and a second signal. The first signal line is configured to connect the first semiconductor device and the second semiconductor device and used to transmit the first signal. The second signal line is configured to connect the first semiconductor device and the second semiconductor device and used to transmit the second signal. The second signal line, the first signal line, the ground line, and the third signal line are disposed in this order. A distance between the first signal line and the ground line is larger than a distance between the first signal line and the second signal line.

A metal substrate includes a first insulating substrate, a second insulating substrate, a first metal layer, a second metal layer and a release layer. The first insulating substrate has a first modified surface and a second surface opposite to the first modified surface. The first metal layer faces the second surface. The release layer is bonded on the first modified surface. The second insulating substrate is bonded on a side of the release layer, such that the release layer is between the first modified surface and the second insulating substrate. The second metal layer is disposed on a side of the second insulating substrate, such that the second insulating substrate is between the release layer and the second metal layer. An original surface roughness of the first modified surface has a variation substantially less than 10% after the first modified surface is released from the release layer.

A display device includes a display panel, a data driver which transmits a data voltage to the display panel, a first flexible printed circuit board attached to the display panel and including an input side wiring electrically connected to the data driver, a first printed circuit board (PCB) electrically connected to the input side wiring to transmit a high-speed driving signal to the data driver, and a metal tape overlapping the input side wiring in a plan view and attached on the first flexible printed circuit board, where a part of the metal tape overlapping the input side wiring in the plan view defines an opening.

A flexible and/or stretchable structural system for transmitting electrical signal between first and second rigid portions comprises a body structure and said first and second portions arranged to said body structure. The modulus of elasticity of said first portion is lower than the corresponding modulus of elasticity of said second portion. In addition the modulus of elasticity of said body structure is lower than the corresponding modulus of elasticity of said second portion. The system comprises also an interface portion, such as e.g. an electrically conducting fabric, textile or knit, which is arranged to said body structure and between said first and second portions. The interface portion electrically connects said first and second portions. The modulus of elasticity of said interface portion is lower than the corresponding modulus of elasticity of said second portion.