Abstract: A method of producing a polyimide film, including obtaining a polyamic acid including a repeating unit of Chemical Formula 1: wherein Ar1 and Ar2 are described in the specification; imidizing the polyamic acid to obtain a partially imidized polyimide; determining a sub-Tg temperature of the partially imidized polyimide; and heating the partially imidized polyimide in at least two steps to obtain a polyimide film, wherein a step transition temperature range is within the sub-Tg temperature ±30° C.

Abstract: Disclosed are an electronic device and a method for managing a specific absorption rate (SAR). In the present disclosure, even if an antenna for second communication is activated while the electronic device transmits/receives wireless signals of a plurality of frequency bands for first communication, an increase in an SAR value by frequency overlapping can be reduced or suppressed.

Abstract: The present disclosure provides an electronic device and a method of operating an electronic device. The electronic device includes a housing; a wireless communication circuit positioned inside the housing; a battery positioned inside the housing; a display exposed through a part of the housing; and a processor positioned inside the housing and electrically connected to at least one of the wireless communication circuit, the battery, and the display, wherein the processor is configured to collect at least one piece of state information that indicates a state of a user, determine at least one piece of specific absorption rate (SAR) characteristic information, which is related to a SAR, based on collected state information, confirm communication power information corresponding to the determined at least one piece of SAR characteristic information, and adjust communication power of the wireless communication circuit based on confirmed communication power information.

Abstract: A method of preparing an optical film, preparing a coating composition including an amic acid-containing polymer represented by Chemical Formula 1 and at least one polymerization aid selected from an alkyl phosphite, an aryl phosphite, an alkyl phosphate, and an aryl phosphate; providing the coating composition on a substrate to form a coating layer; and applying heat to the coating layer to prepare a cured film: wherein, in Chemical Formula 1, are the same or different in each repeating unit, and are each independently at least one selected from an aromatic organic group, an aliphatic organic group, and an alicyclic organic group, and 0?x?1.

Abstract: A method of preparing an optical film, preparing a coating composition including an amic acid-containing polymer represented by Chemical Formula 1 and at least one polymerization aid selected from an alkyl phosphite, an aryl phosphite, an alkyl phosphate, and an aryl phosphate; providing the coating composition on a substrate to form a coating layer; and applying heat to the coating layer to prepare a cured film: wherein, in Chemical Formula 1, are the same or different in each repeating unit, and are each independently at least one selected from an aromatic organic group, an aliphatic organic group, and an alicyclic organic group, and 0?x?1.

Abstract: A display panel includes a plurality of pixels disposed in an active area and arranged substantially in a matrix form including a pixel row and a pixel column, a first gate line disposed adjacent to a first side n of the pixel row and connected to a first pixel in the pixel row, a second gate line disposed adjacent to a second side of the pixel row and connected to a second pixel in the pixel row, a plurality of data lines crossing the first and second gate lines, where the pixels in a pair of adjacent pixel columns are connected to a same data line, and a blocking pattern which overlaps a pixel column disposed in an end portion of the active area.

Abstract: An electronic device is provided. The electronic device includes an outer housing including a first plate, a second plate oriented in an opposite direction of the first plate, and a side member at least partially surrounding a space between the first plate and the second plate and a mid-structure disposed in the outer housing, including a first surface facing the first plate, a second plate facing the second plate, and a third plate facing at least a portion of the side member, and at least partially surrounded by the side member, wherein at least a portion of a side surface of the first plate may be surrounded by the at least a portion of the side member while spaced apart at a first interval, wherein at least a portion of the third surface of the mid-structure may be positioned adjacent to at least another portion of the side member while spaced apart from a second interval, and wherein the second interval may be smaller than the first interval.

Abstract: There is provided an apparatus for driving a motor including: a converter applying an input voltage to each phase winding of the motor; and a processor controlling a phase current flowing to the phase winding to which the input voltage is applied to be increased or decreased in a preset reference range and controlling phase commutation of the motor based on a change in the phase current.

Abstract: A slot die includes a material distribution chamber configured to distribute a casting solution supplied to the material distribution chamber, and a lip in which a slot including an expansion portion is defined and through which the casting solution distributed in the material distribution chamber is discharged, where a width of the expansion portion taken in a first direction is expanded from one side of the expansion portion to a lip end facing the one side and the one side of the expansion portion is apart from the lip end by a predetermined length taken along a second direction which is perpendicular to the first direction and substantially parallel to a flow direction of the casting solution.

Abstract: Provided is an apparatus for controlling charging of a portable terminal equipped with a solar battery that converts solar energy into an electrical energy, the apparatus including a thermistor in which a resistance value changes according to a temperature change; a comparator which outputs a first signal when a temperature surrounding the thermistor is less than a preset reference temperature as determined by the resistance value change of the thermistor according to the temperature change and outputs a second signal when the temperature is at least the preset reference temperature or more; and a charging unit which is activated and receives the electrical energy from the solar battery to charge a battery when the first signal is inputted from the comparator, and is deactivated and blocks the charge of battery in case the second signal is inputted.

Abstract: There is provided an apparatus for driving a motor including: a converter applying an input voltage to each phase winding of the motor; and a processor controlling a phase current flowing to the phase winding to which the input voltage is applied to be increased or decreased in a preset reference range and controlling phase commutation of the motor based on a change in the phase current.

Abstract: A film manufacturing apparatus includes: a material supply unit which supplies an intermediate film; a pre-heating unit which pre-heats the intermediate film supplied from the material supply unit; a stretching unit which stretches and performs a first heat-treatment to the intermediate film supplied through the pre-heating unit; a heating treatment unit which performs a second heat-treatment to the stretched intermediate film supplied from the stretching unit; a clipping device which clips lateral ends of the intermediate film to transfer the intermediate film and applies a transverse directional tension to the intermediate film; and a cutting device disposed in at least one of the stretching unit and the heat-treatment unit, wherein the cutting device separates the lateral ends from a center portion of the intermediate film by cutting the intermediate film.

Abstract: A slot die includes a material distribution chamber configured to distribute a casting solution supplied to the material distribution chamber, and a lip in which a slot including an expansion portion is defined and through which the casting solution distributed in the material distribution chamber is discharged, where a width of the expansion portion taken in a first direction is expanded from one side of the expansion portion to a lip end facing the one side and the one side of the expansion portion is apart from the lip end by a predetermined length taken along a second direction which is perpendicular to the first direction and substantially parallel to a flow direction of the casting solution.

Abstract: A colorless transparent polyimide having a thickness of about 1 micrometer to about 250 micrometers, an average coefficient of thermal expansion measured in a machine direction and a transverse direction of less than or equal to about 80 parts per million/° C., an average in-plane retardation of less than or equal to about 20 nanometers, an average Yellowness Index of less than or equal to 6, and a transmittance for light at a wavelength of 370 nanometers to 740 nanometers of greater than or equal to about 80%.

Abstract: A method of producing a polyimide film, including obtaining a polyamic acid including a repeating unit of Chemical Formula 1: Chemical Formula 1 wherein Ar1 and Ar2 are described in the specification; imidizing the polyamic acid to obtain a partially imidized polyimide; determining a sub-Tg temperature of the partially imidized polyimide; and heating the partially imidized polyimide in at least two steps to obtain a polyimide film, wherein a step transition temperature range is within the sub-Tg temperature±30° C.

Abstract: A liquid crystal device including an array substrate facing an opposite substrate; and a liquid crystal layer between the array and opposite substrate, the array substrate including a gate electrode and gate line on a base substrate; a gate insulating layer covering the gate electrode and including a trench crossing the gate line; a semiconductor layer on the gate insulating layer and including a channel area overlapping the gate electrode, a source area at one side of the channel area, and a drain area at another side of the channel area; a pixel electrode on the gate insulating layer and spaced apart from the semiconductor layer; a source electrode connected to the source area; a drain electrode connected to the drain area and the pixel electrode; a data line connected to the source electrode and being inside the trench; and a common electrode insulated from the pixel electrode.

Abstract: A display panel includes a plurality of pixels disposed in an active area and arranged substantially in a matrix form including a pixel row and a pixel column, a first gate line disposed adjacent to a first side n of the pixel row and connected to a first pixel in the pixel row, a second gate line disposed adjacent to a second side of the pixel row and connected to a second pixel in the pixel row, a plurality of data lines crossing the first and second gate lines, where the pixels in a pair of adjacent pixel columns are connected to a same data line, and a blocking pattern which overlaps a pixel column disposed in an end portion of the active area.

Abstract: A display panel includes a first substrate, a second substrate which faces the first substrate, is smaller than the first substrate so that an edge of the first substrate is exposed in a plan view, a fixing member disposed on the exposed edge of the first substrate, and a bonding member disposed between the first substrate and the fixing member.

Abstract: A tenter apparatus for clipping a film includes a frame including a supporting surface supporting the film, and a clip arm which is installed to the frame and rotatable relative to the frame, clips the film along with the supporting surface of the frame and includes a plurality of first contact protrusions which is disposed at a bottom surface of the clip arm and contacts the film.

Abstract: A method of manufacturing a polyimide film includes: extruding a polyimide film including polyimide and a solvent; first drying the extruded polyimide film; stripping the first-dried polyimide film; second drying the stripped polyimide film to remove a residual solvent in the polyimide film; and stretching the second-dried polyimide film, wherein an amount of the residual solvent in the second-dried polyimide film is equal to or less than about 10 weight percent.