Provided is a heat-sensitive recording material which uses a polyolefin resin as a base for a support but brings about less inferior appearance such as curling and irregularities and which has an excellent resolution and can provide a vivid recorded image in a high density. The heat-sensitive recording material comprises a void-containing stretched film comprising a crystalline polypropylene resin and dicyclopentadiene petroleum resin as essential components and a heat-sensitive recording layer formed on a surface thereof.

1. Field of the Invention
The present invention relates to a heat-sensitive recording material which has an excellent resolution and can provide a vivid recorded image in a high density and which brings about less inferior appearance such as curling and irregularities after recording.
2. Description of the Related Art
In general, known is a heat-sensitive recording material prepared by providing a heat-sensitive color developing layer on a support such as paper, synthetic paper or a plastic film. Contained in the heat-sensitive color-developing layer are a colorless or light-colored developing material, a developer, a binder, a filler, a sensitizer, a lubricant and other auxiliary agents, and a color-developed image is obtained by momentary chemical reaction caused by heating by means of a hot pen or a thermal head.
A recording apparatus for such heat-sensitive recording material is inexpensive and small-sized, and maintenance thereof is easy, so that it is widely used as a recording medium in printers for a facsimile, various calculators, medical instruments, an automatic ticket distributor, a heating copying machine and other various apparatuses.
In particular, a heat-sensitive recording material comprising a support of synthetic paper or a plastic film is used when a water resistance and a strength are required or an image printer in which a uniformity and a high resolution are required to a recorded image is used.
Most synthetic papers and plastic films used as a support for a heat-sensitive recording material are produced by using a polyolefin resin or a polyester resin as a base, blending it with a white inorganic pigment and stretching it in machine direction and in transverse direction in order to provide it with a whiteness and a cushioning property.
Among them, in the case of a heat-sensitive recording material using a polyolefin resin as a base for a support, there has been the problem that recording in a high density by means of a thermal head results in allowing the support to shrink due to transmission of heat to bring about inferior appearance such as curling and irregularities. In order to solve these problems, a method in which a support is subjected to heat treatment in a rolling state is proposed, but it is not necessarily satisfactory. On the other hand, in the case of a heat-sensitive recording material using a polyester base resin as a base for a support, curling and irregularities are not caused, but the cost grows high. Accordingly, desired is a heat-sensitive recording material in which an inexpensive polyolefin base resin is used for a base and which brings about less inferior appearance such as curling and irregularities.
An object of the present invention is to provide a heat-sensitive recording material which uses a polyolefin resin as a base for a support but brings about less inferior appearance such as curling and irregularities and which has an excellent resolution and can provide a vivid recorded image in a high density.
Intensive researches repeated by the present inventors have resulted in finding that the object described above can be achieved by a heat-sensitive recording material in which used as a support is a void-containing stretched film comprising a crystalline polypropylene resin and a dicyclopentadiene petroleum resin as essential components and in which a heat-sensitive recording layer is formed on a surface thereof, and thus they have completed the present invention.
The present invention comprises the following structures.
(1) A heat-sensitive recording material comprising a void-containing stretched film comprising a crystalline polypropylene resin and a dicyclopentadiene petroleum resin as essential components and a heat-sensitive recording layer formed on a surface thereof
(2) The heat-sensitive recording material as described in the above item (1), wherein the void-containing stretched film comprising a crystalline polypropylene resin and a dicyclopentadiene petroleum resin as essential components is a void-containing laminated stretched film obtained by laminating a surface layer film comprising a composition of the crystalline polypropylene resin on both faces of a base layer film comprising a composition prepared by blending 5 to 180 parts by weight of a dicyclopentadiene petroleum resin having a softening point (ring and ball method) of 160 to 200xc2x0 C. with 100 parts by weight of the crystalline polypropylene resin and then stretching it at an area magnification of 5 times or more.
(3) The heat-sensitive recording material as described in the above item (1), wherein the void-containing stretched film comprising a crystalline polypropylene resin and a dicyclopentadiene petroleum resin as essential components is a compression-treated void-containing laminated stretched film obtained by hot-compressing the void-containing stretched film as described in the above item (2) at a temperature of 50 to 160xc2x0 C. and a pressure at which the void-containing laminated stretched film described above does not become transparent.
The embodiment of the present invention shall be explained below.
In the heat-sensitive recording material of the present invention, the void-containing stretched film which is the support is a void (fine void)-containing single layer stretched film or a void-containing laminated stretched film obtained by stretching at an area magnification of 5 times or more, a single layer non-stretched film sheet obtained from a resin composition (hereinafter referred to as a resin composition for a void-containing stretched film) comprising a crystalline polypropylene resin and a dicyclopentadiene petroleum resin as essential components or a laminated non-stretched film sheet which comprises the single layer non-stretched film sheet described above as a base layer and in which a surface layer film comprising a composition of the crystalline polypropylene resin is laminated on at least one face of the base layer.
The crystalline polypropylene resin used for the resin composition for the void-containing stretched film described above or the composition (hereinafter referred to as the resin composition for the surface layer film) of the crystalline polypropylene resin for the surface layer film described above is a crystalline homopolymer of propylene, a binary or higher copolymer of propylene with at east one selected from ethylene and xcex1-olefin having 4 or more carbon atoms or a mixture thereof. To be specific, it includes propylene base polymers having a crystal melting point such as crystalline polypropylene containing a boiling heptane-insoluble part of 70% or more, preferably 80% or more, and crystalline propylene copolymers containing a propylene component of 70% or more, such as a crystalline ethylenexc2x7propylene copolymer, a crystalline propylenexc2x71-butene copolymer, a crystalline propylenexc2x71-hexene copolymer and a crystalline ethylenexc2x7propylenexc2x71-butene copolymer.
The crystalline polypropylene resins used for the resin composition for the void-containing stretched film and the resin composition for the surface layer film may be the same or different.
The crystalline polypropylene resin has a melt flow rate (measured on a condition 14 (test temperature: 230xc2x0 C. and test load: 21.18 N) shown in Table 1 of JIS K-7210 ┌Flow test method of thermoplastic plastics┘, hereinafter referred as MFR) of 0.5 to 20 g/10 minutes, preferably 0.5 to 10 g/10 minutes.
The dicyclopentadiene petroleum resin used for the resin composition for the void-containing stretched film described above has preferably a softening point (ring and ball method) of 160 to 200xc2x0 C.
If the dicyclopentadiene petroleum resin has a softening point (ring and ball method) of lower than 160xc2x0 C., the void-containing single layer stretched film is not obtained by stretching the single layer non-stretched film or sheet obtained from the resin composition for the void-containing stretched film. On the other hand, if it exceeds 200xc2x0 C., the dispersibility into the crystalline polypropylene resin tends to be reduced.
The dicyclopentadiene petroleum resin having a softening point (ring and ball method) of 160 to 200xc2x0 C. includes petroleum resins which are high polymers containing a cyclopentadiene component of 50% by weight or more and having a softening point (ring and ball method) failing in a range of 160 to 200xc2x0 C. and which have a high softening point among petroleum resins obtained by polymerizing fractions comprising as principal components, at least one (hereinafter referred to as a cyclopentadiene component) selected from cyclopentadiene, dicyclopentadiene, alkyl-substituted products and oligomers thereof and mixtures thereof which are obtained by steam cracking of petroleum naphtha, and hydrogenated dicyclopentadiene petroleum resins having a softening point (ring and ball method) of 160 to 200xc2x0 C. and an iodine value of 20 or less which are obtained by hydrogenating the resins containing a cyclopentadiene component of 50% by-weight or more among the petroleum resins described above under conditions of a temperature of 150 to 300xc2x0 C. and a hydrogen pressure of 10 to 150 kgf/cm2 in the presence of a solvent with a catalyst comprising metals such as vanadium, nickel and cobalt or an oxide thereof.
In the resin composition for the void-containing stretched film described above, the dicyclopentadiene petroleum resin having a softening point (ring and ball method) of 160 to 200xc2x0 C. is blended in an amount of 5 to 180 parts by weight, preferably 30 to 180 parts by weight and more preferably 50 to 180 parts by weight per 100 parts by weight of the crystalline polypropylene resin. If a blending amount of the dicyclopentadiene petroleum resin described above is less than 5 parts by weight per 100 parts by weight of the crystalline polypropylene resin described above, caused are the problems that the resulting void-containing stretched film has an unsatisfactory covering property and that the resulting heat-sensitive recording material is short of a cushioning property to deteriorate contact with a thermal head and therefore the image is broken, and brought about is the problem that the inferior appearance such as curling and irregularities is generated. On the other hand, if the blending amount exceeds 180 parts by weight, caused is the problem that when stretching the non-stretched film sheet, breakage takes place very often to deteriorate the processing stability.
In the heat-sensitive recording material of the present invention, if the void-containing stretched film which is the support is a laminated stretched film which comprises a film comprising the resin composition for the void-containing stretched film described above as a base layer film and which is obtained by laminating a surface layer film comprising the composition of the crystalline polypropylene resin on both faces of the base layer film and then stretching it at an area magnification of 5 times or more, the resulting heat-sensitive recording material is particularly reduced in generation of inferior appearance such as curling and irregularities after recording, and therefore it is preferred.
A surface layer film surface of the laminated stretched film described above has to be smooth in order to improve contact with a thermal head, and therefore inorganic fillers having a large particle diameter which may markedly damage the smoothness are not preferably added to the resin composition for the surface layer film.
In the resin composition for the void-containing stretched film described above, an inorganic filler powder can be substituted for a part of the dicyclopentadiene petroleum resin described above as long as the object of the present invention is not damaged. The inorganic filler powder described above includes calcium carbonate, talc, titanium oxide and silica each having an average particle diameter of 0.01 to 20 xcexcm, preferably 0.01 to 10 xcexcm and more preferably 0.1 to 5 xcexcm, and calcium carbonate is advantageous from a viewpoint of a cost. They may be used alone or in combination of two or more kinds thereof.
Various additives which are publicly known to be added to polypropylene, for example, phenolic antioxidants, thioether antioxidants, phosphorus antioxidants, higher fatty acid metal salts such as calcium stearate, lubricants such as fatty acid amides, pigments, foaming agents and polyethylenes and ethylene-propylene rubber as added polymers can be added, if necessary, to the crystalline polypropylene resin used for the resin composition for the void-containing stretched film described above or the resin composition for the surface layer film described above as long as the object of the present invention is not damaged.
The resin composition for the void-containing stretched film described above or the resin composition for the surface layer film described above can be prepared by stirring and mixing the crystalline polypropylene base resin and the additives by means of an ordinary blender or mixer. Further, it can be molten, kneaded and pelletized by means of a conventional extruding machine.
In the present invention, publicly known methods such as a T-die film extrusion method and a blown film extrusion method can be given as examples of a method for obtaining a non-stretched single layer film or sheet from the resin composition for the void-containing stretched film described above. Further, publicly known laminate processing methods such as a co-extrusion method in which molten resins are turned into a multilayer film in a die and an extrusion lamination method in which a surface layer film is further superposed on a base layer film prepared by extrusion are used as a method for obtaining a non-stretched laminated film sheet from the resin composition for the void-containing laminated stretched film.
A stretching method for obtaining the stretched film from the non-stretched film sheet described above and the stretching conditions shall not specifically be restricted. That is, it may be either monoaxial stretching or diaxial stretching, and it is preferably diaxial stretching. Either of publicly known monoaxial and diaxial stretching machines can be used.
The stretching conditions are different depending on the stretching machine used. The temperature is set to not higher than a softening point of the petroleum resin contained in the composition, and the film is stretched at an area magnification of 5 times or more. In the case of diaxial stretching, the area magnification is preferably 9 times or more.
In the case of a diaxial stretching machine, it may be either a simultaneous stretching system or a sequential stretching system.
In the present invention, when stiffness is required to the void-containing single layer stretched film or void-containing laminated stretched film described above which is the support for the heat-sensitive recording material, it is preferably a compression-treated void-containing single layer stretched film or a compression-treated void-containing laminated stretched film obtained by hot-compressing the void-containing single layer stretched film or void-containing laminated stretched film described above at a temperature of 50 to 160xc2x0 C. and a pressure at which the voids do not disappear.
The hot-compressing described above can be carried out by means of a hot press or a hot-compressing roll.
With respect to the hot-compressing conditions, the void-containing single layer stretched film or void-containing laminated stretched film described above is heated up to 50 to 160xc2x0 C. and then hot-compressed to a thickness of 50 to 90 based on a thickness of 100 before hot-compressing at a linear pressure of 50 to 400 kg/cm by means of a hot compressing roll. However, if the film is heated too high, the voids described above completely disappear, so that it has to be hot-compressed at a lower hot-compressing temperature than a temperature at which the voids disappear. Further, the voids disappear in a certain case by virtue of pressure, and therefore hot-compression has to be carried out on conditions on which restoration in a thickness direction and disappearance of the voids are not caused while controlling the temperature and the pressure.
In the heat-sensitive recording material of the present invention, a thickness of the void-containing stretched film which is the support shall not specifically be restricted and is preferably 25 to 300 xcexcm. When the void-containing stretched film is a laminated film, a thickness of the base layer film accounts for 50% or more of a whole thickness of the laminated film.
A density of the void-containing stretched film described above shall not specifically be restricted, and 0.3 to 0.8 g/cm3 can be given as an example thereof.
In the heat-sensitive recording material of the present invention, a heat-sensitive color-developing layer is formed on the surface of the void-containing stretched film which is the support. In the present invention, a method for forming the heat-sensitive color-developing layer described above shall not specifically be restricted, and publicly known methods can be used.
Capable of being given as examples of the heat-sensitive color-developing layer described above are a combination of colorless or pale colored basic dyes with inorganic or organic acid substances, a combination of higher fatty acid metal salts such as ferric stearate with phenols such as gallic acid and a combination of diazonium compounds with couplers and basic substances.
In general, the heat-sensitive color-developing layer can be formed by preparing a heat-sensitive color-developing layer-coating solution by adding to the combination described above, a binder, a filler, a sensitizer, a dispersant, a lubricant and other auxiliary agents such as a UV absorber, an antioxidant, a fluorescent dye, a mold-releasing agent, a water resistant agent and a defoaming agent, coating it on the support and drying it.
Publicly known substances and methods described in, for example, Japanese Patent Application Laid-Open No. 70479/1990, Japanese Patent Application Laid-Open No. 219276/1992 and Japanese Patent Application Laid-Open No. 142034/1997 can be used for specific components used for the heat-sensitive color-developing layer described above and a method for preparing the heat-sensitive color-developing layer-coating solution described above.
In the heat-sensitive recording material of the present invention, the kind and the amounts of various components used for the heat-sensitive color-developing layer-coating solution are decided according to the performances and the recording aptitude required and shall not specifically be restricted. When a combination of a basic dye (a color-developing dye) with an organic acid substance is used for the components of the heat-sensitive color-developing layer-coating solution, usually used are 0.05 to 2 parts of the basic dye, 0.01 to 2 parts of a sensitizer and 0.5 to 4 parts of a filler each per one part of the organic acid substance, and a binder accounts suitably for 5 to 25% of the whole solid matters.
In the heat-sensitive recording material of the present invention, the heat-sensitive color-developing layer-coating solution may be prepared according to the example described above, and commercially available heat-sensitive color-developing layer-coating solutions may be used.
In the heat-sensitive recording material of the present invention, a method for forming the heat-sensitive color-developing layer shall not specifically be restricted, and it is formed by a method in which the coating solution is applied by, for example, air knife coating and blade coating and dried. A coating amount of the coating solution shall not specifically be restricted and is controlled usually in a range of 2 to 12 g/m2 in terms of a dried weight.
In the heat-sensitive recording material of the present invention, an overcoat layer of a high molecular substance can further be provided on the heat-sensitive color-developing layer for the purpose of elevating the protection. Further, an undercoat layer containing an organic filler or an inorganic filler can be provided between the heat-sensitive color-developing layer and the support for the purpose of elevating the protection and the sensitivity.
In the heat-sensitive recording material of the present invention, capable of being suitably used are such various techniques publicly known in the heat-sensitive recording material production field that when the heat-sensitive color-developing layer is formed only on one face of the void-containing stretched film which is the support, a face on which the heat-sensitive color-developing layer is not formed is subjected to adhesive treatment to process the recording material into an adhesive label.


A reactive distillation method comprises introducing a feed stream to a reactive distillation column, contacting the feed stream with one or more catalysts in the reactive distillation column during a distillation, and removing one or more higher alcohols during the distillation from the reactive distillation column as a bottoms stream. The feed stream comprises one or more alpha hydrogen alcohols, and the feed stream reacts in the presence of the one or more catalysts to produce a reaction product comprising the one or more higher alcohols.

N-Butanol and ethyl acetate are commercially significant organic compounds having use in a wide variety of applications and which are produced in quantities exceeding 1 million tons per year. N-Butanol can be produced from several different reactions. The most common method for making n-butanol is hydroformylation. Propylene reacts with syngas over cobalt or rhodium catalysts at high pressures to produce an aldehyde (butyraldehyde), which is then hydrogenated over a nickel catalyst to give the alcohol. The drawbacks of such a process include the high energy costs associated with the generation of syngas, the use of a potentially non-renewable feedstocks (propylene and syngas are typically sourced from petroleum and natural gas, respectively), and the complexity of the process which requires multiple reactors and, typically, homogenous hydroformylation catalysts.
N-Butanol can also be produced from an aldol condensation reaction followed by hydrogenation. This method converts acetaldehyde to butanols, although the high toxicity and limited availability of acetaldehyde make such a process unattractive. Some processes, for example U.S. Pat. Nos. 1,992,480 and 8,071,823 both of which are incorporated herein by reference in their entirety, utilize a gas phase reaction to provide butanol.
Direct fermentation of sugars is another process for production of n-butanol. As a bioprocess this method suffers from long process times and large separation requirements in addition to the need for specialized microbes necessary to make butanol directly from sugars.
Ethyl acetate can also be produced from several different reactions. The most common method for making ethyl acetate is the esterification of acetic acid and ethanol. This reaction requires two raw material supplies with the associated storage or production facilities. In locations without a sufficient supply of reliable, inexpensive acetic acid, this process may not be economically viable.
Ethyl acetate can also be produced from the oxidation of ethanol over supported precious metal catalysts. The high costs of precious metal catalyst can also make this option uneconomical.
The Tishchenko reaction (dimerization of aldehydes into esters) is another alternative process for production of ethyl acetate. Dimerization of acetaldehyde results in ethyl acetate, however, aldol condensation also occurs, resulting in by-products such as 2-butanone and 2-propanol, both of which form azeotropes with ethyl acetate. In addition, the Tishchenko reaction requires a supply of acetaldehyde, which may not be readily available and can be difficult to store and handle due to its high toxicity.
1-Hexanol and 1-octanol are both made industrially via oligomerization of ethylene using triethylaluminum, followed by oxidation of the alkylaluminum intermediate. In this process, the triethylaluminum does not serve as a catalyst, but rather is a reactant that is not easily regenerated. In particular, the reaction scheme starts with metallic aluminum and results in the formation of aluminum oxide and/or hydroxide upon completion of the reaction. The triethylaluminum is expensive since it requires metallic aluminum as a precursor. The triethylaluminum is also a pyrophoric material and presents hazards for using and storing. This process also requires a potentially non-renewable feedstock (ethylene) typically source from steam cracking of petroleum.


A voltage sag and over-voltage compensation device for an AC electric power distribution system employing cascaded switching devices and a pulse width modulated autotransformer. The autotransformer typically includes lower, center, and upper poles or taps with cascaded switching devices for selectively connecting the voltage source (i.e., a phase of the distribution line) between the lower pole and the center or upper poles. Each stage of the cascaded switching device includes a switching element located within a full-bridge rectifier circuit to allow bi-directional switching through each switching element (i.e., switching through the same switching element during the positive and negative portions of the AC voltage cycle). Each full-bridge rectifier also includes a snubber circuit connected in parallel with a corresponding switching element to absorb the current discharge caused by switching the input power supply to the autotransformer through the corresponding switching device under non-zero current conditions. On the output side, the voltage sag and over-voltage compensation device includes a load capacitor to smooth the voltage-corrected AC power supply toward a sinusoidal power supply at the system frequency, and a notch filter to remove noise created by the switching elements.

The present invention relates generally to the field of electric distribution power systems and, more particularly, relates to a voltage sag and over-voltage compensation device for an AC electric power distribution system employing a pulse width modulated autotransformer.
Voltage sags and over-voltage conditions occasionally occur on AC power distribution systems for a variety of reasons, such as high resistance faults in the distribution system, fault clearing, switching large loads characterized by arcing during connection or disconnection of the load, other types of transient circuit overloading (e.g., dynamic disturbances), high load inductance during unusually heaving load periods, and line capacitance during unusually light load periods. Although these voltage conditions may be short lived, such as a few cycles in a, 50 or 60 Hertz electric power system for transient disturbances and fault clearing events, they can nonetheless cause sensitive loads, such as computer systems and manufacturing operations, to experience equipment damage and, in some cases, to drop off line. Therefore, devices that compensate for these voltage sags and over-voltage conditions, so that the loads receive an uninterrupted supply of the intended line voltage, serve an important function for these types of sensitive loads.
Certain conventional approaches to AC voltage compensation use traditional inverter technology, which rectifies the AC line power into DC power and stores the DC energy, typically in capacitors, batteries, or a flywheel during normal system operations. Then, during a voltage sag, the sag supporter device inverts the stored DC energy into AC power and delivers this power through a series-connected transformer to supply the missing voltage. This conventional inverter approach is complex and requires a large number of power switching elements to create the replacement voltage profile. The switching elements are relatively expensive and render the sag supporter financially infeasible for many applications. In addition, the duration of the available voltage support is limited by the amount of energy that can be stored prior to the voltage sag, and can therefore require large storage devices. Large storage devices can significantly increase the size of the device, often making pole-mounted configurations impractical. Alternatively, the circuitry required to repeatedly discharge and charge capacitors during the voltage sag condition presents complex control and timing challenges associated with continually recharging the capacitors to the proper level, and further increases the cost and sophistication of the device. In addition, the presence of a series-connected transformer in the power line during normal circuit operation causes significant power losses, even when voltage support is not required.
In another conventional approach, a tap switching series-connected transfonner, often called a voltage regulator, may be used to compensate for voltage sag conditions. However, the large number of windings and switching elements required to provide a range of voltage sag compensation increases the cost of the voltage regulator and, in any event, limits the device to providing a discrete number of voltage steps in the output power supply. In addition, due the implementation time required for tap-changing voltage correction, these systems are ill suited to following fast changing voltage sag or over-voltage events, which typically occur when the cause of the voltage sag or over-voltage event involves a fault or switching event characterized by arcing. Arcing, by it""s very nature, is erratic in behavior and changes quickly during the event as attachment points move around. Again with this type of device, the presence of a series-connected transformer in the power line during normal operations causes significant power losses.
Transient over-voltage conditions caused by the tap switching series-connected transformer presents another significant disadvantage of the tap-switching voltage regulator approach. This typically occurs when a breaker or fuse clears a fault causing the voltage sag, which abruptly returns the system to normal voltage. This typically occurs at a zero-current condition, which is followed buy the series-connected transformer boosting the voltage on it""s output well above it""s normal level for approximately 8 milliseconds until the transformer can be returned to its normal setting, which usually occurs at the next zero-current condition. This xe2x80x9ccurrent-zero switchingxe2x80x9d limitation occurs with these devices because they typically employ thyristor switching elements, which can only switch during zero-current conditions. Thus, notwithstanding multiple winding ratios and multiple switching elements, these systems still impose a significant over-voltage on the load at the conclusion of many voltage sag events.
Therefore, there is a need in the art for a compact, cost effective voltage sag and over-voltage compensation device that does not routinely impose over-voltage conditions on the loads they are designed to protect. There is also a need for a voltage sag and over-voltage compensation device that does not require a large number of switching devices, large power storage devices, or a series-connected transformer in the power line during normal operation of the circuit.
The present invention meets the needs described above in a voltage sag and over-voltage compensation device employing a pulse width modulated autotransformer. The device preferably operates at AC electric power distribution system voltages, but may be designed to operate at other voltage levels. This device significantly improves over conventional inverter technology in that no energy storage devices are required. The present invention also significantly improves over conventional tap-switching transformer technology in that no over-voltage is imposed on the load when a voltage sag event is over. Moreover, the technology of the present invention is much simpler than prior approaches for AC voltage compensation in that it reduces the number of active switching elements and uses well developed autotransformer technology as the basic design element. This advantageously allows switching to occur at higher voltages with lower currents than occurs in prior designs. In addition, a single switching frequency with a single pulse width for any given voltage sag or over-voltage condition makes the control system for the present invention relatively simple to design and implement. The end result is a comparatively uncomplicated design, which exhibits lower cost and higher reliability, while providing equivalent or improved functionality in comparison to prior art voltage compensation technologies.
Generally described, the present invention includes a voltage sag and over-voltage compensation device that receives electric power from an oscillating at a system frequency, adjusts the voltage of the power, and delivers a corresponding voltage-corrected AC power supply to a load connected across an upper pole and a neutral pole of the device. The voltage sag and over-voltage compensation device includes an autotransformer having a first winding around a flux linking core and connected between the neutral pole and a center pole, and a second winding around the flux linking core and connected between the center pole and the upper pole. The autotransformer also includes a center-pole switch for selectively connecting the AC power source between the neutral and center poles when the center-pole switch is gated to a closed or xe2x80x9conxe2x80x9d configuration, and for selectively disconnecting the AC power source from connection between the neutral and center poles when the center-pole switch is gated to an open or xe2x80x9coffxe2x80x9d configuration. The voltage sag and over-voltage compensation device also includes a control unit for selectively gating the center-pole switch between the open configuration and the closed configuration multiple times per cycle of the system frequency to generate the voltage-corrected AC power supply for delivery to the load.
The center-pole switch is typically located within a full-bridge rectifier circuit connected between the AC power source and the center pole to allow bi-directional switching through a single switching element (i.e., switching through the same element during the positive and negative portions of the AC voltage cycle). The voltage sag and over-voltage compensation device also typically includes a center-pole snubber connected in parallel with the center-pole switch to absorb the current discharge caused by switching the power supply to the autotransformer under non-zero current conditions. In particular, the center-pole switch and the center-pole snubber are typically connected in parallel and located within the full-bridge rectifier circuit connected between the AC power source and the center pole.
For relatively high voltage applications, the center-pole switch includes a cascade of individual center-pole switching devices connected in series and operated substantially simultaneously, typically from a common gating signal. In this case, each individual center-pole switching device is located within an individual full-bridge rectifier circuit, and a plurality of center-pole snubber circuits may each be connected in parallel with one of the individual switching devices within its corresponding full-bridge rectifier circuit. Each center-pole snubber circuit may include a resistor and a capacitor connected in series and a diode connected in parallel with the resistor.
To smooth the voltage-corrected AC power supply toward a sinusoidal power supply at the system frequency, the voltage sag and over-voltage compensation device also includes a load capacitor connected between the neutral and upper poles of the autotransformer. The control unit typically gates the center-pole switch at a gating frequency, and to remove noise created by the switching elements, the voltage sag and over-voltage compensation device typically includes a notch filter connected between the neutral and upper poles or the autotransformer. This notch filter is preferably configured to reduce power disturbances occurring in the voklage-corrected AC power supply within a filter frequency range about the gating frequency. Specifically, the notch filter may include an inductor, a resistor, and a capacitor connected in series.
To permit normal operation of the power circuit without having the autotransformer connected in series in the power line, the voltage sag and over-voltage compensation device typically includes an upper-pole switch for selectively connecting the AC power source between the neutral and upper poles of the autotransformer when the upper-pole switch is gated to a closed or xe2x80x9conxe2x80x9d configuration, and for selectively disconnecting the AC power source from connection between the neutral and upper poles when the upper-pole switch is gated to an open or xe2x80x9coffxe2x80x9d configuration. To absorb the current discharge caused by switching the power supply to the autotransformer under non-zero current conditions, the voltage sag and over-voltage compensation device typically an upper-pole snubber connected in parallel with the upper-pole switch. For relatively high voltage applications, the upper-pole switch may Include a cascade of individual upper-pole switching devices connected in series and operated substantially simultaneously, typically from a common gating signal. In this case, each individual upper-pole switching device may be located within an individual full-bridge rectifier circuit, and a plurality of upper-pole snubber circuits may each be connected in parallel with one of the individual switching devices within its corresponding full-bridge rectifier circuit. Each upper-pole snubber circuit may include a resistor and a capacitor connected in series and a diode connected in parallel with the resistor.
In a first mode of operation, the control unit gates the upper-pole and center-pole switching devices in substantial unison to maintain these switches in opposing configurations. That is, the upper-pole switch is gated off when the center-pole switch is gated on, and vice versa. More specifically, the control unit detects a voltage sag or over-voltage condition in the AC power source, and in response to detecting this condition, the control unit continually gates the upper-pole and center-pole switching devices in substantial unison to maintain these switches in opposing configurations to create a desired voltage-corrected AC power supply. The control unit then detects a cessation of the voltage sag or over-voltage condition in the AC power source, and in response to detecting the cessation of the condition, gates the center-pole switching device to an open configuration, gates the upper-pole switching device to a closed configuration, and discontinues further gating of switching devices.
In a second mode of operation, the control unit detects a voltage sag or overvoltage condition in the AC power source, and in response to detecting this condition, gates the upper-pole switching device to an open (i.e., by-pass) configuration. In this case, while the upper-pole switching device is held in the open (i.e., by-pass) configuration, the control unit continually gates the center-pole switching device between the open and closed configurations to create a desired voltage-corrected AC power supply. The control unit then detects a cessation of the voltage sag or over-voltage condition in the AC power source, and in response to detecting the cessation of the condition, gates the center-pole switching device to an open configuration, gates the upper-pole switching device to a closed configuration, and discontinues further gating of switching devices.
In view of the foregoing, it will be appreciated that the voltage sag and overvoltage compensation device of the present invention is a comparatively uncomplicated design, which exhibits lower cost and higher reliability, while providing equivalent or improved functionality in comparison to prior art technologies. The present invention also improves over prior AC voltage compensation technology in that no energy storage devices are required, and no over-voltage is imposed on the load at the conclusion of a voltage sag or event. The specific techniques and structures employed by the invention to improve over the drawbacks of the prior voltage sag and over-voltage compensation devices, and to accomplish the advantages described above will become apparent from the following detailed description of the embodiments of the invention and the appended drawings and claims.

Voltage sag and over-voltage compensation device with pulse width modulated autotransformer


A drum commutator for electrical machines has an isolating material drum and a plurality of commutator plates composed of an electrically conductive material, the commutator plates being mounted on a periphery of the isolating material drum near one another and electrically separated from one another by axial slots, each of the commutator plates being provided with a surface coating composed of carbon material and with a connecting lug for an armature winding of an electrical machine, each of the commutator plates having at least one depression at its lower side placed on the isolating material drum and being also provided with a radial passage which opens in the depression and has a reduced size relative to the depression, the carbon material of the surface coating filling the passage and the depression as a one-piece structure.

The present invention relates to a drum commutator for electrical machines.
More particularly, it relates to a drum commutator which has an oscillating material drum and a plurality of commutator plates extending from its periphery and provided with a surface coating of carbon material and with a connecting lug for an armature winding of the electrical machine.
Drum commutators of the above mentioned general type are known in the art. They are utilized in wet electric motors in feed aggregates for aggressive liquids, for example in fuel pumps of motor vehicles. The surface coating of carbon material, for example graphite, which is resistant to the aggressive medium to be fed, protects the metallic surface of the commutator plates which are usually composed of copper. Otherwise, they would strongly oxidize and corrode during a current transfer with the resulting high and non-uniform voltage drop at the commutator.
Drum commutators of this type are disclosed for example in the German document DE-GM 89 07 045, page 2. Here the surface coating is formed as a graphite ring which is surface-treated on its inner surface and then soldered to the drum commutator. Then the graphite ring is slotted or in other words segmented so that a graphite coating is produced for the individual commutator plates. In this known plan commutator disclosed in this reference the commutator body composed of a synthetic plastic material is provided with a copper coating in which the commutator segments are formed. The plan surface of the commutator segments is provided correspondingly with a carbon coating which extends via form-locking holding means through the commutator plates into a corresponding recess in the commutator body and is anchored there.


A domestic appliance includes at least one component having a surface that can become laden with organic dirt. The surface includes a photocatalyst and is made from a primary-formed first material in which the photocatalyst is dispersed. A photoradiation source is provided for irradiating the photocatalyst with an activating electromagnetic radiation.

The present invention relates to a domestic appliance having at least one component which comprises a surface that can become laden with organic dirt, said surface comprising a photocatalyst and said surface being associated with a photoradiation source for irradiating the photocatalyst with an activating electromagnetic radiation.
A domestic appliance of this type is disclosed by each of the publications JP 11-123299 A, JP 11-137894 A and JP 11-137881 A. Accordingly, a washing solution container and, contained therein, a washing drum rotatable about a vertical axis and coated with layers of a photocatalyst are arranged in a washing machine, and a movable ultraviolet light source is provided by means of which the layers can be irradiated with ultraviolet light to activate the photocatalyst. Parts of the washing drum that could shade a layer of the photocatalyst from the photoradiation source can be made from material which is transparent to the radiation.
In a water-carrying domestic appliance, in general, objects that are soiled with different types of dirt are cleaned. Thus, in a dishwasher, food residues arise and the range of soiling of laundry items to be cleaned in a washing machine is usually greater. It is common to all water-carrying domestic appliances that soiling occurs therein, particularly at the less accessible sites, and can accumulate at such sites. Such soiling can be a good nutrient medium for microorganisms such as bacteria and fungi in a moist warm atmosphere prevailing in such a domestic appliance and can thereby cause additional soiling.
For example, in a laundry treatment device such as a washing machine, on frequent use of wash programs with cold washing solutions, in a long phase of inactivity with the door closed or under unfavorable siting conditions, bad odors and/or visible soiling can occur. A possibility for cleaning at such poorly accessible regions is therefore desirable. It is also desirable that preventative measures can be taken against microorganisms even where no externally perceptible effects occur. Overall, therefore, it is useful if such nuisance soiling can be prevented or, as far as possible, eliminated.
A variety of measures against such soiling are known from the prior art. In particular, sometimes, device cleaning programs are offered with which, at high temperatures and with the aid of washing agents and possibly with increased washing solution levels and/or at higher drum rotation speeds, i.e. with an increased input of mechanical energy, built-up dirt can be combated. Also known are the use of ozone and UV-C radiation to remove organic dirt. Also known are measures for killing microorganisms using Ag+ or Cu+ ions in a washing solution or on the surfaces of the materials in contact with the washing solution. Other methods aim at the thermal destruction of any microorganisms present by increasing the temperature at the surfaces of the components in contact with the washing solution by means of direct or indirect energy transfer (water, steam, microwaves). Also known from the aforementioned documents is the use of photocatalysts. A disadvantage of said known methods and measures is, for example, the high cost for equipment and/or operation thereof in order to achieve relevant effects. In the case of the use of Ag+ and Cu+ ions, disadvantageous effects involve the pollution of ground and waterways.
From the documents WO 2005/108505 A1, EP 1 205 244 A1 and EP 1 204 245 A1, minerals are known, the surfaces of which are able to activate oxygen molecules by irradiating them with visible or ultraviolet light such that the readiness thereof to undergo chemical reactions is significantly increased. This effect is commonly known by the designation "photocatalysis". Each of said minerals is a semiconductor with a band gap which permits the creation of an electron-hole pair in said semiconductor by a quantum of visible or ultraviolet light. It is also to be assumed that a mineral of this type has an affinity for oxygen, which permits activation of the oxygen by transferring energy from the semiconductor. The known minerals include titanium dioxide, cadmium sulfide, tungsten trioxide and zinc oxide.
It is also known to alter a semiconductor of this type by doping or similar modification with elements such as carbon, boron, nitrogen, phosphorus, sulfur, chlorine, arsenic, selenium, bromine, antimony, tellurium and iodine such that the wavelength of light needed to evoke the photocatalysis is increased. Titanium dioxide is cited as an example: in order to evoke the photocatalysis with pure titanium dioxide, irradiation with ultraviolet light having a wavelength of between 380 nm and 400 nm corresponding to the UV-A range is required. According to the publication WO 2005/108505 A1, it is possible to generate a titanium dioxide modified with carbon and having the form of a powder at which photocatalysis occurs merely on irradiation with visible light. This powdered photocatalyst is usable in components made from concrete, ceramics, paper and woven fabrics in the building industry and the automotive industry, as well as in photovoltaic cells, air-conditioning units and apparatus for cleaning or sterilizing air or water.
Of the known materials which exhibit photocatalysis under corresponding conditions, titanium dioxide is particularly distinguished by being chemically largely inert and non-toxic, as well as being known in many uses, particularly as a white pigment and being produced and marketed on a large industrial scale.

Domestic appliance having a surface which comprises a photocatalyst


An improved roller skate includes a shoe portion, front and rear wheels, and a bracket coupling the wheels to the shoe portion. The have a "generally" spherical shape which allows the skater to maintain a rolling surface of each wheel on the floor or ground, while leaning the skate by a relatively large degree with respect to a line extending perpendicular to the floor or ground. Each wheel has a rigid inner core and a softer outer cover. The inner core includes an axle housing connected to a hollow, "generally" spherical, rigid shell by a plurality of radially extending spokes. The bracket coupling the wheels to the shoe portion includes arms coupled to the wheel axles. The shape of the bracket and bracket arms are designed for strength as well as to allow for a high degree of skate inclination (lean or angle) with respect to the ground or floor without contacting and scraping the ground or floor.

1. Field of the Invention
The present invention relates to improved roller skates and methods for making the same and, in particular embodiments, to a high-performance roller skates having a light-weight wheel bracket and light-weight wheels defining generally spherical shaped roller surfaces which allow a skater to lean or incline the skate to a relatively large degree.
2. Description of Related Art
Early roller skate designs employed generally disk-shaped wheels having relatively narrow outer peripheral surfaces defining the rolling surfaces. The rolling surfaces are the surfaces of the wheels which contact the floor or ground during a controlled roll on the floor or ground. The rolling surface of a typical conventional wheel design abruptly ends at each side wall of the wheel. Thus, if a skater leaned too far to one side while skating, the rolling surfaces of the skate wheels would lose contact with the floor or ground, causing the skater to lose control and/or fall to that side.
Various prior roller skate designs employed four of such disk-shaped wheels supported on a pair of axles. Two wheels were supported on one axle mounted toward the front of the skate and two wheels were supported on the other axle mounted toward the back of the skate. Early roller skate wheels were made of generally hard materials, such as steel or ceramic materials. More modern roller skate wheels have been made of a softer rubber or plastic material.
Recently, "in-line" skates have become popular. These "in-line" skates have, for example, four generally disk-shaped wheels, each supported on its own axis, arranged in a line along the length of the skate. In various "in-line" skate designs, the mounting brackets for coupling the wheels and axles to the shoe part extend adjacent the side walls of the wheels. The location of these mounting brackets tends to allow portions of the bracket to scrape the ground or floor, if the skater where to lean the skate too far to either side. Thus, the degree to which the skater can lean, for example, during high speed turns or trick maneuvers, is severely limited by the wheel mounting bracket, as well as by the generally disk-like shape of the wheels.
"In-line" skates can, to some extent, give the skater a riding sensation which is closer (relative to the two-wheels -per-axle roller skates) to that of riding on ice skates. Typical ice skates are provided with a thin blade for contacting the ice. Generally, the bottom edge of the thin blade can remain in contact with the ice, even when the skater leans the skate to one side, e.g., during a high-speed turn. However, as discussed above, typical "in-line" roller skates cannot be leaned to a significant degree to one side without scraping the wheel bracket against the ground and/or without the user's ankles collapsing inward and the rolling surface of the wheels losing contact with the ground, as discussed above. Thus, typical "in-line" skates still do not provide performance characteristics equal to or near those provided by ice skates.


A process to produce ammonia from a hydrocarbon feedstock, involving basically the following steps:. Dividing the feedstock into two fractions, PA0 Subjecting the first fraction to a primary steam reforming reaction, at high pressure and moderate temperature, PA0 Combining the effluent from the primary reforming with the second fraction of the feedstock, and subjecting the mixture thereof to a secondary adiabatic reforming reaction with an amount of air in excess to that needed for ammonia synthesis, PA0 Subjecting the synthesis gas produced to a CO shift conversion reaction, and then to CO.sub.2 removal by solvent scrubbing, while the gas released by pressure letdown of said solvent is preferably recycled back upstream of the secondary reforming, PA0 Methanation of the residual carbon oxides, PA0 Removing the excess nitrogen present in the gas by cryogenic separation, PA0 Compressing and feeding the final synthesis gas into an ammonia synthesis loop, PA0 Recycling the purge gas from said ammonia synthesis loop to upstream the cryogenic separation.

The present invention relates to the production of ammonia, and the corresponding synthesis gas, from a hydrocarbon containing feedstock. The industrial synthesis of ammonia is achieved through a synthesis gas containing a molal ratio of H.sub.2 /N.sub.2 as close as possible to the stoichiometric value, that is 3.0, and some quantities of inert gases such as methane and argo, which one tries to reduce to the minimum. Processes for the production of ammonia by steam reforming of hydrocarbons are described in U.S. Pat. Nos. 2,829,113, 3,278,452, 3,264,066, 3,388,074 and 3,442,613.
In the process most commonly used for the production of ammonia synthesis gas, starting from a feedstock ranging from natural gas to naphtha, the total feedstock undergoes first a primary steam reforming reaction, at a temperature of about 800.degree. C. and under a pressure of between about 25 to 35 bars, inside refractory tubes containing a reforming catalyst and externally heated by a set of burners. In said primary steam reforming, the amount of steam used in the reaction is usually expressed by the steam/carbon ratio, which is the number of moles H.sub.2 O per atom of hydrocarbon carbon; said ratio is very often higher than 3.0, and usually closer to 4.0. The gas produced by the primary reforming reaction is then subjected to a secondary reforming reaction, in the presence of a reforming catalyst, at about 1000.degree. C. and under the same pressure, in a reactor operating under essentially adiabatic conditions, by reacting with the amount of air which is just necessary to obtain in the final synthesis gas a molal ratio of H.sub.2 /N.sub.2 equal 3.0. Said temperature of about 1000.degree. C. is imposed by the need to have less than about 0.6 percent methane in the gas effluent from said secondary reforming, on a dry gas basis, in order to avoid excessive purge rates in the ammonia synthesis loop. Consequently, as the amount of air introduced in said secondary reforming is limited by the stoichiometry of the ammonia synthesis, it is found that the effluent gas temperature from the primary steam reforming should be above a certain minimum, which is about 800.degree. C. The effluent gas from the secondary reformer is then treated for shift conversion of CO to CO.sub.2, then scrubbed with an appropriate solvent to remove essentially all the CO.sub.2 it contains, then methanated to convert into methane essentially all the residual carbon oxides it contains, which are poisons to the ammonia synthesis catalyst.
The above described conventional process for the production of ammonia synthesis gas has basically two major drawbacks. Firstly, a large amount of steam must be used in the primary steam reforming reaction, that is a steam/carbon ratio of at least about 3.0, due to the minimum ratio allowable to prevent carbon formation on the reforming catalyst, and in order to obtain an acceptable methane content at the outlet of the primary and secondary reformers. Said large amount of steam penalizes the conventional process in two ways, because not only does it represents an energy burden, but also because of the high investment required in the equipment to produce said steam. Secondly, because of the minimum temperature of about 800.degree. C. at the outlet of the primary reformer, the metallurgy of the tubes used in said reformer requires restricting the operating pressure of the process to about 40 bars; consequently, a large amount of energy is required to compress the final synthesis gas produced, the volume of which is about four times that of the feedstock, to reach the ammonia synthesis pressure, usually comprised between 180 and 380 bars.
The process described in U.S. Pat. No. 3,4442,613 has the merit of avoiding the aforementioned second drawback, by using in the secondary reforming an amount of air appreciably larger than that required by the stoichiometry of the ammonia synthesis, the excess nitrogen being removed downstream in a cryogenic separation step. However, the amount of steam to be used in the primary reforming of this process is as large as that of the conventional process. Furthermore, the process of U.S. Pat. No. 3,442,613 operates with a methane content in the feed to the secondary reformer of less than 50 percent by volume, on a dry gas basis, which means the process does not take full advantage of reducing the degree of reforming in the primary reformer. Furthermore, said process requires the expansion of the process gas in a gas expander to produce the refrigeration required in the cryogenic purifier, which is an appreciable loss of energy, especially when considering that the expansion of hydrogen produces much less refrigeration than that of other gases such as nitrogen.
The process described in U.S. Pat. No. 3,278,452 permits the direct production of an ammonia synthesis gas with the stoichiometric composition, while achieving a substantial saving on the steam required for the primary reforming, because only a fraction of the feedstock may be treated in the latter, the other fraction going directly to the secondary reformer. Nevertheless, this process requires the use of oxygen enriched air in the secondary reformer, and the production of said oxygen is expensive in investment and in energy consumption. In addition, said process requires two or several steps in the secondary reforming reaction, with oxygen injection at the inlet of each step. Now it is virtually impossible to build such a system, because the oxygen to be injected in the second and subsequent steps is mixed with a gas at very high temperature coming from the first step, and this is a source of very elaborate technological problems; not only very special and expensive materials of construction must be used in the mixing zone, but also expensive provision must be made in the design for access to said zone for maintenance purposes. Furthermore, as the temperature of the reacting gas mixture increases regularly from the first to the last catalyst bed, the total volume of catalyst thus required is appreciably larger than that needed to carry the same reaction in a single step: in the latter case, all the catalyst would be at very high temperature, higher than or equal to the outlet temperature, because the reaction would be initiated before reaching the catalyst bed, thus raising appreciably the temperature of the mixture, and it is well known that the higher temperature of the catalyst increases appreciably the reaction rate and therefore reduces the volume of catalyst required.
The main object of the present invention is precisely to avoid simultaneously the two above mentioned drawbacks of the conventional process, that is on one hand to reduce appreciably the operating temperature of the primary reformer, which consequently allows an increase in the operating pressure and to reduce the corresponding fuel requirements, and on the other hand to reduce appreciably the amount of steam required for the process, thereby achieving an overall energy saving.
Another object of the present invention is to achieve a saving in investment as compared to the conventional steam reforming process for the production of ammonia.
Still another object of the present invention is to replace part of the expensive fuel required in the conventional process, that is a fuel with low sulfur and heavy metals contents, by electric power which would be cheaper if produced in power plants using coal or nuclear energy.
Furthermore, in the conventional process, the purge gas from the ammonia synthesis loop is either used as fuel or treated in costly additional facilities to recover the hydrogen therein. Another object of the present invention is to upgrade the hydrogen contained in said purge gas without the need to invest in additional facilities.

Process for the production of ammonia and the corresponding synthesis gas


A filter support tube for use in a filter cartridge including a helical wound wire defining a cylinder and a plurality of reinforcing strips extending generally parallel to a longitudinal axis of the helical wire cylinder and circumferentially spaced from one another about a perimeter of the cylinder. The multiple turns of the helical wire are embedded in the reinforcing strips and extend through it. The wire is coated with a bonding agent to permit the wire to bond to the reinforcing strips and to provide corrosion resistance. The reinforcing strips embedding the wire lock the wire in the desired helical configuration and provide the required column strength for the filter support tube.

The present invention relates generally to the construction of replacement filter cartridges and, more particularly, to a filter support tube for use in a filter cartridge.
At the heart of all replacement filter cartridges is a means of structural mechanical support. For four decades or more, a perforated metal support tube has been widely used as a structural support member for all types of pleated paper or other types of filter cartridges and also for coalescers to provide mechanical strength against rupture from the "outside in" direction or from the "inside out" direction. Also, the perforated metal support tube provides a means of creating longitudinal support for a gasket seal.
There have been many improvements in the perforated metal support tube for filter cartridges over the years but the basic design of this structure has remained the same. Basically, it is a relatively thin-walled metal cylinder perforated with small holes over its total surface area. This design has several fundamental weaknesses which has rendered it far from the ideal as a structural strength member.
One fundamental weakness is that the "open area", in other words the perforations or holes, provided in the cylinder wall to allow adequate fluid flow affects the structural strength of the tube. To provide the barest minimum of structural strength of the tube it is necessary to limit perforations to only about 35% to 40% of the total surface area of the cylinder wall. This means that about 60% of the surface area of the cylinder wall is completely blocked to fluid flow. It is readily apparent that this restriction to fluid flow is extremely detrimental to filter performance in that the filter life is decreased, initial and final differentials are much higher, and a loss in filter efficiency is incurred. Further, this restricted flow area becomes particularly significant in the case of air or gas filtration where the pressure differential across the perforated metal cylinder is frequently greater than the pressure differential across the filter media itself.
Another fundamental weakness is that manufacturing of the perforated metal support tube for a filter element requires that a relatively thin perforated metal be used in order to permit easy formation of the cylindrical shape of the tube. However, such thin perforated metal has very low strength to resist crushing when pressure differentials build up on the filter media in the "outside in" direction especially. Improvements have been made by corrugating the metal to provide ridges which add to structural strength. Also, perforated metal cylinders are now available which include a helical lock seam which greatly strengthens the structural member but further complicates the "blinding" of the available surface area. Frequently, it is necessary to reinforce the perforated metal cylinders with a spiral helical wire which is spot welded to the perforated metal to provide additional structural strength. The helical lock seam also tends to collapse longitudinally when trying to effect a gasket seal.
Still another fundamental weakness is the use of small perforations or holes which adversely affects filter efficiency. The small holes (for instance 1/8 to 1/4 inch diameter) in the perforated metal cylinder causes localized high velocities in fluid flow which tends to drive small particles of one to two microns in size through the filter media by the force of momentum (1/2 mv.sup.2). This is particularly significant in the case of coalescer elements where the coalescer performance specifications require Red Iron Oxide as the basic solids contaminant with greater than 94% of these particles being less than one micron in size.
Consequently, a need still exists for an alternative filter support tube design that will overcome the weaknesses described above as inherent with the prior art perforated metal design.

Filter support tube for a filter cartridge


An electronic device is provided. The electronic device includes a display configured to output a screen on which a web browser is executed, an input device comprising input circuitry configured to integrate with the display or be independent of the display, a communication circuit configured establish a communication channel with the network via a wired or wireless communication connection, a processor configured to be electrically connected with the communication circuit, the display, and the input device, and a memory configured to store a program and instructions for the web browser and be electrically connected with the processor. The memory stores the instructions which, when executed by the processor, cause the electronic device to perform at least one operation comprising: displaying the screen where the web browser is executed on the display, receiving a web document via the communication circuit, displaying the content on the first region based on the first code and displaying an object which may interact with the content on the second region based on the second code.

With the development of electronic technologies, various types of electronic products have been developed and distributed. Recently, there has been a growing interest in electronic devices which support virtual reality (VR) environments. For example, a head-mounted device (HMD) which may be worn on a head of a user has been actively developed. The HMD may detect motion or movement of the user and may provide part of an omnidirectional image (or multi-view image) corresponding to the motion or movement to the user.
If displaying a webpage using a web browser, an electronic device which supports the VR environments may display the webpage on a planar region and may display a user interface of a web browser on a peripheral region except for the region which displays the webpage. If an image provided by the electronic device which supports the VR environments is an omnidirectional image, an area of the peripheral region is larger than that of the region which displays the webpage. Thus, there is a need for a method for using the peripheral region in various manners to effectively use a space in the omnidirectional image.

Electronic device and method for outputting electronic document in electronic device


In a semiconductor module, an upper arm switching element is integrated to a high-potential conductor coupled to a high-potential electrode of a power source, and a lower arm switching element is integrated to a load conductor coupled to a load. A first connecting conductor has a first end connected to the upper arm switching element and a second end connected to the load conductor. A second connecting conductor has a first end connected to the lower arm switching element and a second end connected to a low-potential conductor coupled to a low-potential electrode of the power source. At least one of the first connecting conductor and the second connecting conductor serves as a shunt resistor for detecting an electric current flowing in the at least one.

Conventionally, a semiconductor module having semiconductor switching elements has been known. The semiconductor elements constitute a bridge circuit such as a three-phase inverter circuit. In regard to such a bridge circuit, it has been known to arrange a shunt resistor between the switching element of a lower arm part and a ground for detecting an electric current supplied to a load. For example, the shunt resistor is made of a metallic low-resistance material, as described in JP2001-118701A.
Conventionally, the shunt resistor has been used for detecting the electric current, and has been provided as a separate member from a conductor, such as a lead frame, that forms a driving current path of the bridge circuit. In a semiconductor module where a connecting conductor for connecting the switching element and the lead frame and the shunt resistor for detecting an electric current between the switching element and the lead frame are both required, two separate members are used. In such a case, however, the number of components and the number of wiring portions are likely to increase.

Semiconductor module with switching elements


A method of forming oxide-nitride-oxide (ONO) dielectric of a SONOS-type nonvolatile storage device is disclosed. According to a first embodiment, a method may include the steps of forming a tunneling dielectric (step 102), forming a charge storing dielectric (step 104), and forming a top insulating layer (step 106) all in the same wafer processing tool. According to various aspects of the embodiments, all layers of an ONO dielectric of a SONOS-type device may be formed in the same general temperature range. Further, a tunneling dielectric may include a tunnel oxide formed with a long, low pressure oxidation, and a top insulating layer may include silicon dioxide formed with a preheated source gas.

As is well known, semiconductor devices can include an insulated gate field effect transistor (IGFET) type device. IGFET-type devices typically include a transistor gate separated from a channel region by a dielectric. A potential applied to a gate can then be varied to alter channel conductivity.
While many IGFET type devices are volatile (e.g., conventional metal-oxide-semiconductor FETs), nonvolatile devices may also include IGFET-like approaches. Nonvolatile IGFET-like devices typically retain electric charge through one or more methods (e.g., storing, trapping charge). One conventional nonvolatile device can be a floating gate electrically erasable programmable read only memory (EEPROM). A floating gate EEPROM can include a floating gate electrode situated between a control gate and a channel. Charge, including electrons and/or "holes", may be stored in a floating gate electrode. Such a charge may alter a threshold voltage of a resulting nonvolatile IGFET-type device. As will be noted below, a drawback to any floating gate device can be higher programming and/or erase voltages with respect to other nonvolatile approaches.
Another nonvolatile IGFET type device can include a dielectric interface to trap charge. For example, devices have been proposed that include a metal gate formed over a dielectric of silicon nitride and silicon dioxide. Such devices have been referred to as metalnitride-oxide-semiconductor (MNOS) devices. A drawback to many MNOS devices has been lack of charge retention and/or uniformity of programming.
A third type of nonvolatile device may include one or more dielectric layers for storing charge. Such devices may be referred to generally as silicon-oxide-nitride-oxidesilicon (SONOS) type devices. One very basic type of SONOS device may include a polycrystalline silicon ("polysilicon") gate formed over a dielectric layer that includes a silicon nitride layer sandwiched between silicon dioxide layers.
SONOS devices can have lower programming voltages than other conventional nonvolatile devices, such as some types of floating gate devices. In addition, the SONOS fabrication process can be compatible with standard complementary metal oxide semiconductor (CMOS) process technology. To maintain this compatibility, SONOS devices may be scaled along with other transistors used in the process. The ability of SONOS devices to maintain performance and reliability as they are scaled can be an important feature.
To better understand the formation of SONOS devices, a conventional way of forming a SONOS device is set forth in FIGS. 11 and 12A to 12F. FIG. 11 is a flowchart illustrating various process steps involved in creating an integrated circuit containing SONOS devices. FIGS. 12A-12F set forth a number of side cross-sectional views of a portion of an integrated circuit containing SONOS devices following the various conventional process steps described in FIG. 12.
The conventional process described in FIG. 11 is designated by the general reference character 1100. A conventional process 1100 may include the steps of growing a tunnel oxide (step 1102) in a furnace. Subsequently, wafers that now include the tunnel oxide can be transferred from a furnace to a different machine for growing other layers in an ONO dielectric for a SONOS-type device. In FIG. 11, such a step may include transferring wafers to a chemical vapor deposition (CVD) machine (step 1104).
A conventional method 1100 may further include depositing a silicon nitride layer over tunnel oxide in a CVD machine (step 1106), depositing a top oxide layer over a nitride layer in the same or a different CVD machine (step 1108), and depositing a polysilicon gate layer (step 1110).
The above steps may form various layers for a SONOS-type device. Such layers can then be patterned to form a SONOS-type transistor. Patterning steps may include forming a gate mask (step 1112), etching gate structures (step 1114), and depositing and etching a spacer layer (step 1116).
Referring to FIG. 12A, a side cross-sectional view of a portion of an integrated circuit prior to the beginning of a conventional process 1100 is shown. An integrated circuit portion includes a substrate 1200, and may include isolation regions 1202 formed by prior process steps. As an example, isolation regions 1202 may be formed by various conventional isolation processes including but not limited to shallow trench isolation (STI) or the local oxidation of silicon (LOCOS).
It is noted that a substrate 1200 may also include various impurity regions, formed by ion implantation and/or other diffusion methods. As but a few examples, n-type wells may be formed in a p-type substrate (or vice versa), or p-type wells may be formed within n-type wells (or vice versa).
Referring again to FIG. 11, a conventional process 1100 may begin by growing a tunnel oxide (step 1102) in a furnace. A portion of an integrated circuit following step 1102 is set forth in FIG. 12B. Referring to FIG. 12B, a portion of an integrated circuit includes a tunnel oxide 1204 on a substrate 1200.
A conventional process 1100 can continue by transferring a wafer from a furnace to a chemical vapor deposition (CVD) machine (step 1104). A conventional process 1100 can continue by depositing a silicon nitride layer in a CVD machine (step 1106). A portion of an integrated circuit following step 1104 is set forth in FIG. 12C. Referring to FIG. 12C, an integrated circuit may now be situated within a CVD machine. The integrated circuit portion can now include a nitride layer 1206 deposited over a tunnel oxide 1204. A nitride layer 1206 can conventionally include essentially only silicon nitride (Si3N4).
A conventional process 1100 can continue by depositing a top oxide layer (step 1108) in a chemical vapor deposition (CVD) machine. Referring to FIG. 12D, an example of a portion of an integrated circuit following step 1106 is set forth. A tunnel oxide 1204, a nitride layer 1206 and a top oxide layer 1208 may now be formed over a substrate 1200. A top oxide layer 1208 can be conventionally formed by chemical vapor deposition (CVD).
At this point, in a conventional process 1100, three layers of an ONO dielectric have been created in at least two different machines. More particularly, a tunnel oxide 1204 may be formed in one machine (a furnace particular adapted for growing an oxide), while a nitride layer 1206 and/or a top oxide layer 1208 may be formed in a different machine (a machine particularly adapted for depositing CVD films)
A conventional process 1100 can continue by depositing a polysilicon gate layer (step 1110). An example of a portion of an integrated circuit following a step 1108 is set forth in FIG. 12E. Referring to FIG. 12E, a polysilicon gate layer 1210 has been deposited on a top oxide layer 1208. As also shown in FIG. 12E, a gate protection insulator 1213 may also be formed over polysilicon gate layer 1210. It is noted that a polysilicon gate layer 1210 is conventionally formed in a different reaction chamber than the previous oxide-nitride-oxide layers. Further, a gate protection insulator 1213 may be formed in a different reaction chamber than a polysilicon gate layer 1210.
At this point, in a conventional process 1100, the silicon-oxide-nitride-oxide-silicon (SONOS) layers can correspond to a substrate 1200, tunnel oxide 1204, nitride layer 1206, top oxide layer 1208, and polysilicon gate layer 1210, respectively.
A conventional process 1100 may continue with lithography and etch steps to isolate and form SONOS devices. In conventional lithography, a gate mask may first be formed (step 1112). An example of a portion of an integrated circuit following step 1110 is set forth in FIG. 12E. A gate mask material 1212 can be deposited and patterned using any of various lithographic techniques. A gate mask material 1212 may generally consist of a photoresist material.
Following the formation of a gate mask (step 1112), gate structures can be etched (step 1114). Referring now to FIG. 12F, a portion of an integrated circuit following step 1112 is set forth. A suitable etching process can remove portions of the tunnel oxide 1204, nitride layer 1206, top oxide layer 1208, and polysilicon gate layer 1210 that are not covered by gate mask material 1212. In this manner, SONOS device gate structures 1216 can be formed on a substrate 1200.
A conventional process 1100 can continue by depositing and etching a spacer layer (step 1116). An example of a portion of an integrated circuit following step 1116 is set forth in FIG. 12F. Referring to FIG. 12F, a spacer layer 1214 can be formed that surrounds and electrically isolates SONOS gate structures 1216. A spacer layer 1214 may include silicon dioxide. Note that in FIG. 12F, a gate mask layer 1212 has been removed by suitable process means.
While the conventional process described may produce an integrated circuit containing SONOS devices of reasonable quality and performance, certain aspects of a process may be important in maintaining device performance and/or reliability. This can be particularly true as SONOS devices are scaled to realize lower programming voltages and/or in order to maintain compatibility with CMOS process technology.
ONO dielectric layers in SONOS-type devices may suffer from certain drawbacks as a SONOS-type device is scaled down, particularly as the thickness of the dielectric layers are scaled down to a point at which a tunnel oxide 1204 can be less than 25 Å thick, a nitride layer 1206 can be less than 100 Å thick and a top oxide layer 1208 can be less than 50 Å thick.
A tunnel oxide 1204 can provide an insulating layer between a silicon substrate and a nitride layer 1206. A nitride layer 1206 can be a dielectric layer between a tunnel oxide 1204 and a top oxide layer 1208 that can trap and/or store electric charge. A top oxide layer 1208 can function to electrically isolate a nitride storage layer 1206 and a polysilicon gate layer 1210.
For the reasons set above, the quality of a tunnel oxide 1204, a nitride layer 1206 and a top oxide layer 1208 can be important features in an ONO dielectric of a SONOS-type device.
The performance of an ONO dielectric of a SONOS-type device can be affected by various factors including thickness, uniformity of thickness, particle count, stress in the dielectric layers, and the quality of a interfaces present in an ONO dielectric.
Thickness can be an important character of an ONO dielectric in a SONOS-type device as a thin but robust dielectric can be important in maintaining device performance and reliability. This may be particularly important as SONOS devices are scaled to realize lower programming voltages and/or integrated to be compatible with decreasing geometry CMOS process technology.
Uniformity of the thickness of dielectric layers across a wafer can also be an important feature in a process. Uniformity in layer properties across a wafer can translate into uniformity in the performance of all devices formed on at the same wafer. This can increase yields and help ensure that device specifications are met.
Particle count can be another important character of ONO dielectric of SONOS-type devices. Increased particle account typically results in direct reductions in yields. Consequently, minimizing particle count is typically a continuing goal in semiconductor manufacturing processes.
Stress may also reduce the quality of ONO dielectric layers of SONOS-type devices.
In particular, stress may occur when different materials undergo thermal expansion at different rates. Temperature variation can be the main cause of the thermal expansion that can lead to stress in different dielectric layers. Stress can cause cracking in the dielectric layers, spiking in metal lines and/or void formation in conductive layers, thus reducing the quality of an ONO dielectric.
Interface quality may be affected by foreign elements, or the like. Such foreign elements may typically be introduced at an interface during a manufacturing process. As but a few of the many possible examples, foreign elements may include organic films, undesirable elements like boron, and/or particles.
A conventional manufacturing process for a SONOS-type device, such as that described above, can have various drawbacks. In a conventional process, wafers can be transferred to different machines for manufacturing different layers. For example, a tunnel oxide 1204 can be grown in one machine, while the remaining layers including a nitride layer 1206 and a top oxide layer 1208 can be deposited in another machine. A transfer of wafers among different machines can facilitate the introduction of foreign particles or elements onto a wafer, and thus increase a particle count for a wafer. Further, such particles or elements may settle at an interface between dielectric layers. This may adversely affect the performance of an ONO dielectric.
A conventional process can also subject wafers to broad temperature changes in forming different dielectric layers. This may also increase the particle count and increase the stress in dielectric layers. In particular, different layers of a SONOS-type dielectric can be formed under different temperature ranges. In addition to increasing stress, resulting temperature cycles can also cause variations of thickness in different parts of dielectrics.
In light of the limitations of the conventional process set forth above, it would be desirable to provide a method of forming ONO dielectric layers for a SONOS-type device that may have a higher quality than conventional approaches.

Method of manufacturing an oxide-nitride-oxide (ONO) dielectric for SONOS-type devices


A microblog server receives sharing information required for sharing a microblog message transmitted by a microblog client. Generate a microblog data packet according to the sharing information, and transmit the microblog data packet to an instant messaging (IM) client, such that the IM client displays the microblog message to be shared according to the microblog data packet.

At present, network Instant Messaging (IM) tools have been accepted by most Internet users and have become an indispensable software tool for the users. The IM tools have been widely used in both leisure and works of the users. The IM tools mainly realize a one-to-one friend chatting mode or a one-to-N chatting mode in a group or a discussion group. With development of Internet applications, applications of microblogs continue to grow. Microblog provides users with a new communication mode by a sentence of about 140 words. Microblogs can be spread and transferred very rapidly, which realize a one-to-indefinite chatting mode across the one-to-one and one-to-N mode. The one-to-indefinite mode means that one user may listen to microblogs distributed by millions of users.
The listening relationship of the microblog is an application of a loose relationship chain. One user may select to listen to users according to his interests. Thus, broadcast messages of these users may appear in homepage messages of a listener. However, a friend relationship in the instant messaging is an application of a strong relationship chain. It can be seen that, the listening relationship in the microblog and the friend relationship in the instant messaging complement each other to some extent.
Since the listening relationship in the microblog and the friend relationship in the instant messaging complement each other to some extent, after seeing a useful microblog message, a microblog user may desire to share this microblog message with his IM friend, so as to trigger a further communication with the IM friend.
At present, the microblog user shares the microblog message with the IM friend mainly through a pasting method which includes the following operations.
At step 11, a microblog message to be shared is copied at a microblog client or in a microblog page, the microblog message is converted into a plain text message.
At step 12, a chatting window with an IM friend is opened at an IM client or in an IM page, and the plain text message is pasted in the chatting window.
At step 13, contents in the chatting window are transmitted to the IM friend via a message tunnel with the IM friend.
It can be seen from the above that, the conventional method for sharing a microblog message with the IM friend is rather complex and inconvenient. The efficiency of sharing the microblog message is relatively low.

Method, apparatus and system for sharing a microblog message

Tencent Technology (Shenzhen) Company Limited


A tablet cassette for an automatic tablet dispensing system is disclosed. The tablet cassette includes a cylindrical rotor received into a medicine case of the tablet cassette and engaged to a male gear fixed to a motor shaft located within a driving unit. The rotor has a waved guide formed along an conically tapered upper surface thereof and a protrusion formed on a central surface portion thereof so as to smoothly agitate the received tablets and preventing from tangling together with said waved guide. The cylindrical rotor has a plurality of guide teeth formed along an outer periphery of the rotor body and a plurality of insert openings regularly provided between said guide teeth to respectively receive one tablet therein. At least one auxiliary case has an upper and a lower engagement steps formed along the periphery thereof. The upper engagement step has thrust bumps along an upper periphery thereof to facilitate engagement onto an upper portion of the medicine case having a corresponding engagement step formed along an upper periphery thereof, and the lower engagement step of the said auxiliary case has thrust grooves formed in correspondence to the thrust bumps of the medicine case. A cover is provided onto an upper portion of the medicine case or said auxiliary case. The cover includes a porous compartment formed underneath a lower surface thereof, wherein preservatives or demoisturants can be placed.

1. Field of Invention
The present utility model relates to a tablet cassette for an automatic tablet sorting and counting machine commonly referred to as "automatic tablet dispensers". More specifically, the present invention is an improved tablet cassette which is capable of facilitating a tablet packaging operation in a packaging unit of an automatic tablet dispenser by supplying to an output port of a drum the exact desired quantity of tablet.
2. Description of the Prior Art
Automatic tablet dispensers are generally employed in hospitals, pharmacies, and drugstores to automate the output and assembly of corresponding tablets when the prescription is input into a computer. They serve to dispense the per-dosage assembled tablets in individual single serving packages.
A conventional automatic tablet dispenser includes the following: a main computer for calculating an appropriate prescription on the basis of the type of medicine, intake method, daily intake frequency and intake duration depending upon each patient; a tablet dropping unit having a plurality of tablet cassettes and a drum for storing therein and releasing therefrom the tablets in correspondence to the prescription set up in the computer; and a packaging unit disposed below the tablet dropping unit which serves to package a quantity of tablets and release the same to an exterior of the automatic tablet dispenser.
A tablet cassette serves to discharge to-be-packaged tablets on the basis of information input in the main computer. In general, the tablet cassette includes a tablet case having a driving unit and housing a slanted rotor, which rotates in accordance with the driving unit. A plurality of space between a plurality of guide teeth is formed along the outer periphery of the rotor, wherein the tablets are dropped into the space one by one and released by the rotor through an outlet into the tablet dropping unit with the rotation of the rotor.
A predetermined space sufficient to house the tablets therein is provided from the bottom surface of the tablet case. However, the room for the rotor and tablet case relatively becomes narrow due to the assembly clearance which occurs during the assembly of the driving unit, medicine case and rotor. The tablets should be smoothly supplied into the tablet dropping unit with the rotation of the rotor, but the conventional system has a disadvantage in that the space between the rotor and the medicine case cannot be constantly maintained during the assembly or for other reasons. This disadvantage sometimes prevents a timely release of the tablets resulting from jamming or tangling when the tablets in the medicine case are supplied toward the rotor.
Also, conventional tablet cassettes are provided in fixed measurement regardless of tablet size. Thus a different quantity of tablets is received in each cassette depending upon tablet sorts and size and accordingly requiring frequent tablet supplementation.
Furthermore, when a large quantity of small tablets are contained in a tablet cassette, the release duration becomes relatively larger, which can cause the tablets contained therein to be subject to moisture and deformation.

Tablet cassette for automatic tablet sorting and counting machine