Abstract:
An inkjet printhead and a method of manufacturing the same. The inkjet printhead may include a substrate in which a manifold to supply ink is formed in a lower portion of the substrate and a plurality of ink feed holes connected to the manifold are formed in an upper portion of the substrate, feed hole guides that are formed on inner sidewalls of the ink feed holes to define lengths of the ink feed holes, a chamber layer stacked on the substrate, the chamber layer including a plurality of ink chambers connected to the ink feed holes, a plurality of heaters to heat ink inside the ink chambers to generate bubbles, and a nozzle layer stacked on the chamber layer, the nozzle layer including a plurality of nozzles, the ink being ejectable through the nozzles.
Abstract:
A method of manufacturing an inkjet printhead includes preparing a substrate having a heater to hear ink and an electrode to supply current to the heater, applying a crosslinked polymer resist composition to the substrate having the heater and the electrode and patterning the same, and forming a passage forming layer that surrounds an ink passage, patterning the substrate having the passage forming layer by photolithography at least twice, and forming a sacrificial layer having a planarized top surface in a space surrounded by the passage forming layer, applying the crosslinked polymer resist composition to the passage forming layer and the sacrificial layer and patterning the same, and forming a nozzle layer having a nozzle, etching the substrate from the bottom surface thereof to be perforated, and forming an ink supply hole, and removing the sacrificial layer, wherein the crosslinked polymer resist composition comprises a precursor polymer that is a phenolic novolak resin having glycidyl ether functional groups on repeating monomer units.
Abstract:
A hybrid broadcast encryption method is provided. The hybrid broadcast encryption method includes setting initialization values, generating a node secret using the initialization values; generating a private secret using the node secret; sending the node secret and the private secret; generating a broadcast message based on a revoked group; encrypting a session key using a key encryption key (KEK) which is allocated to every user group and the broadcast message; and broadcasting to every user the encrypted session key and the broadcast message.
Abstract:
A user key management method for a broadcast encryption includes assigning node path identifiers (IDs) to nodes arranged in sequence; assigning random seed value keys to the nodes according to the node path IDs; generating key values by repeatedly applying a hash function to the assigned random seed value keys; and assigning the generated key values to the nodes in sequence. Accordingly, it is possible to reduce the transmission overhead that is most important matter in the broadcast encryption to less than the number of the revoked users. Further, there is an advantage that the transmission overhead of the exemplary embodiments of the present invention is remarkably reduced compared with the Subset Difference method.
Abstract:
A method of fabricating a high efficiency inkjet print head includes forming an oxide film on a surface of a substrate, sequentially forming and patterning a heater layer and a wiring layer on the oxide film, forming a passivation layer on the heater layer and the wiring layer and patterning the passivation layer so that a heater is exposed, etching the substrate to form restrictors at both sides of the heater, forming a chamber layer on the passivation layer, forming a sacrificial layer on the chamber layer and polishing the sacrificial layer, forming a nozzle layer on the chamber layer, forming an ink-feed hole at a bottom surface of the substrate, and removing the sacrificial layer. The inkjet print head is capable of reducing energy consumption by fabricating a heater having high efficiency, and capable of maintaining good heating characteristics since an original temperature of the inkjet print head is rapidly recovered after the heater is instantly heated and electric current is not supplied. In addition, since the heater is mounted on the substrate, the inkjet print head can maintain structural integrity, and since the heater is formed in a planar shape without bent portions, the heater can be formed to a uniform thickness.
Abstract:
A system and method for configuring a device using a remote controller are provided. The system includes at least one device which transmits and receives data using a wireless communication connection and performs a preset operation according to a received control signal; a server which communicates data with the at least one device over a radio channel and controls functions of the at least one device; and a short distance wireless communication device that authenticates the at least one device by receiving a device address list through radio communications with the server and assigning a device address selected from the received address list to the at least one device. Thus, inputting password information of the device directly to the server is not required when a new device is configured.
Abstract:
A head of an inkjet printer is formed by bonding of a heater substrate and a nozzle plate. In order to bond the heater substrate where a heater thin film and a protecting film are vapor-deposited, and the nozzle plate where a nozzle is formed, an intermediate layer is formed by forming a thin film of glass on the heater substrate by vapor-depositing, and the nozzle plate is installed on the heater substrate. SiO2 is formed at an interface between the nozzle plate and the heater thin film due to heating and application of an electric field, and thus the nozzle plate and the heater substrate are bonded with an electrostatic force of SiO2. The nozzle plate and the heater substrate are bonded by using the intermediate layer made of the thin film of glass instead of a general polymer as the bonding layer, thereby preventing swelling of the polymer and isolation of layers of the head occurring due to ink penetration into interfaces of the layers. Moreover, a bonding process is performed in wafer units to improve mass productivity.
Abstract:
A photo-curable resin composition, a method of patterning the same, an ink jet head, and a method of fabricating the same. The photo-curable resin composition includes an epoxy compound, a photo-catalyst provided as a photo-initiator, and a non-photo reactive solvent. The photo-catalyst may be a semiconductor material to generate electron-hall pairs using light energy. The semiconductor material is one selected from a group consisting of TiO2, CdS, Si, SrTiO3, WO, ZnO, SnO2, CdSe and CdTe, CdSe and CdTe. The epoxy compound may include a di-functional epoxy compound and a multi-functional epoxy compound. The non-photo reactive solvent may be one or a mixture selected from a group consisting of gamma-butyrolactone (GBL), cyclopentanone, C1-6 acetate, tetrahydrofurane (THF), and xylene. The photo-curable resin composition is patterned to form a fluid channel structure of the ink jet head.
Abstract:
A method of manufacturing a monolithic inkjet printhead. The method may include forming on a substrate a heater for heating ink and an electrode for supplying current to the heater, forming a passage forming layer that surrounds an ink passage by applying negative-type photoresist to the substrate and patterning the same, forming a sacrificial layer having a planarized top surface in a space surrounded by the passage forming layer by repeatedly applying a positive-type photoresist to the substrate having the passage forming layer and patterning the same by photolithography at least twice, forming a nozzle layer having a nozzle by applying a negative-type photoresist to the passage forming layer and the sacrificial layer and patterning the same, etching the substrate from the bottom surface thereof to be perforated and forming an ink supply hole, and removing the sacrificial layer. Since the top surface of the sacrificial layer is planarized, the shape and dimension of the ink passage can be easily controlled, thereby improving uniformity of the ink passage.