A guiding apparatus includes a magnetic field generation unit, a translation mechanism that translates the magnetic field generation unit relative to a subject, a rotation mechanism that rotates the magnetic field generation unit relative to the subject, an input unit that receives first and second information about operations for changing a position a posture of a capsule medical device, respectively and a control unit that controls the translation mechanism and the rotation mechanism on the basis of the first information and the second information such that the magnetic field generation unit is translated and rotated relative to the subject, wherein, when the input unit receives the second information, the control unit corrects a change in the position of the capsule medical device caused by the rotation of the magnetic field generation unit relative to the subject by translating the magnetic field generation unit relative to the subject.

1. Field of the Invention
The present invention relates to a guiding apparatus which guides a capsule medical device introduced into a subject and a capsule medical device guiding system.
2. Description of the Related Art
In the field of endoscopes, a capsule endoscope has been developed which is formed in a size capable of being introduced into the alimentary canal of the subject such as a patient. The capsule endoscope has an imaging function and a wireless communication function in a capsule-shaped casing. The capsule endoscope is swallowed through the mouth of the subject, sequentially acquires image data for the images (hereinafter, also referred to as in-vivo images) of the internal organs of the subject while being moved in the alimentary canal by a peristaltic motion, and wirelessly transmits the acquired image data to a receiving device outside the subject. The image data received by the receiving device is input to an image display device and the image display device performs predetermined image processing on the image data. In this way, the in-vivo image is displayed as a still image or a moving image on a display. The user, such as a doctor or a nurse, observes the in-vivo image displayed on the image display unit and diagnoses the state of the internal organs of the subject.
In recent years, a guiding system including a guiding apparatus which guides the capsule endoscope in the subject using magnetic force (hereinafter, referred to as magnetic guide) has been proposed (for example, see Japanese National Publication of International Patent Application No. 2008-503310). In general, in the guiding system, a permanent magnet (hereinafter, also referred to as an internal permanent magnet) is provided in the capsule endoscope. In addition, the guiding apparatus includes a magnetic field generation unit, such as an electromagnet or a permanent magnet (hereinafter, also referred to as an external permanent magnet), applies the magnetic field to the capsule endoscope introduced into the subject, and magnetically guides the capsule endoscope to a desired position using magnetic attraction generated from the applied magnetic field. In this case, the guiding system includes a display unit which receives the image data acquired by the capsule endoscope and can display the in-vivo image in real time. The user uses an operation input unit provided in the guiding system to perform an operation of magnetically guiding the capsule endoscope, while referring to the in-vivo image displayed on the display unit.

Guiding apparatus and capsule medical device guiding system


A device including a supporting structure, at least one scraping member upwardly and downwardly delimited by upstream and downstream sides, and an elastic material that is overmolded on the scraping member and connecting the scraping member to the supporting structure, the upstream side of the scraping member being covered with the overmolded elastic material.

A device of this type is described in EP 0,891,934. The device includes several scraping members, secured to each other by the elastic material. Said material is overmolded on the downstream side of the various scraping members. A rubber skirt is adhered to the upstream side of the various scraping members. It allows the evacuation of residues detached from the transporting belt by the scraping members.
The subassembly formed by the scraping members and the elastic material is mounted between two support plates of the supporting structure.
Such a scraping device is a complex structure, and is costly to manufacture.
In this context, the invention aims to propose a scraping device that is simpler and less expensive.

Scraping device for a transporting belt and corresponding manufacturing method


The invention is directed to a pump for pumping a viscous fluid. The pump includes a stator body and a rotor body rotatably mounted in the stator body so as to be coaxial therewith. The stator body has a wall structure having a spiral slot formed therein which communicates with a suction connection formed in the stator body for conducting the viscous fluid to be pumped into the slot. A pressure connection is formed in the stator body for conducting the viscous fluid out of the slot. The suction connection and the pressure connection open into respective peripheral annular slots which are formed between a total of at least three sealing rings on the outer surface of the stator body. The channels for liquids provided in a housing can be disposed in any rotational position relative to the stator. This affords the advantage that the pump stator can be seated with any rotational position in a receiving cylinder of the housing. The sealing rings are injection molded on the stator body to define a tight seat in the receiving cylinder of the housing without additional seals. By a simple insertion of the pump rotor, a connection between the connections of the pump and the channels in the housing is provided which is tight with respect to the medium under pressure.

One such simple and cost-effective pump which is both functionally reliable and has a long service life is advantageously used as a lubricating pump in two-stroke engines especially two-stroke injection engines for portable handheld work apparatus such as motor-driven chain saws. The oil pump is used to provide separate lubrication to supply the piston path, the bearing it catera with lubricating oil. Such a pump is also advantageous for supplying lubricating oil for the saw chain of a motor-driven chain saw.
A connection between the suction connection and the pressure connection of the pump and other channels for conducting the lubricating oil must be provided when building a pump of this kind into the housing of a work apparatus. The connection must be tight with respect to the medium under pressure. For this purpose, appropriate sealing rings are mounted in the housing or on the stator of the pump which is both time and work intensive.


A method of detecting focus shift in a lithography process, a method of analyzing an error of a transferred pattern using the same, and a method of manufacturing a semiconductor device using the methods are provided. The focus shift detecting method of a lithography process comprises generating a first contour band of a mask pattern between a first focus and a second focus, generating a second contour of the mask pattern between the first focus and a third focus, and determining whether focus shift of the mask pattern occurs using an intersection of the first contour band and the second contour band.

Lithography refers to a process which is used to manufacture semiconductor integrated circuit elements. A lithography process includes coating a semiconductor wafer so as to have a photosensitive layer and exposing the photosensitive layer by transmitting an actinic light source onto a photomask having an image of an integrated circuit.
The photomask which is used for the lithography process includes various mask patterns. In certain instances, individual mask patterns which are included in the photomask are configured, for example, by combination of various variables such as a shape, a line width, and an interval between patterns.
In the lithography process which forms a semiconductor integrated circuit element on a semiconductor substrate, even though a transferred pattern is formed on the photosensitive layer using an optical focus of an exposure apparatus, a focus shift may occur in one or more mask patterns which are included in the photomask.

Method of detecting focus shift in lithography process, method of analyzing error of transferred pattern using the same and method of manufacturing semiconductor device using the methods

Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do


A hydrogenation catalyst composition for hydrogenating a polymer of conjugated diene is provided. The polymer of conjugated diene is a homopolymer of conjugated diene or a copolymer of conjugated diene and vinyl aromatics. The hydrogenation catalyst composition includes: (a) a titanium compound, (b) a compound of formula (II),

In the industries, the conjugated diene monomers are homo-polymerized or copolymerized to form the polymers with unsaturated alkenyl groups in their molecular chains. These polymers can be beneficially used for vulcanization. However, the existences of a large amount of these unsaturated double bonds result in the poor performances of weathering resistance, heat resistance and anti-oxidation. These conditions become severe for those polymers, such as thermoplastic rubbers with physical crosslinkages, formed by polymerizing the conjugated diene monomers and vinyl aromatic hydrocarbon monomers, and more severe when used with the modifiers of styrene resins and alkenyl resins and with the impact resistance materials. These copolymers find limited applications as outdoor materials because of their poor performances of weathering resistance, heat resistance and anti-oxidation.
For the polymers formed by polymerizing the conjugated diene monomers and vinyl aromatic hydrocarbon monomers, the drawbacks of poor performances of weathering resistance, heat resistance and anti-oxidation for these polymers can be improved by the hydrogenation method to largely reduce the unsaturated double bonds. There are numerous catalysts for hydrogenating the polymers with unsaturated double bonds. These hydrogenation catalysts can be classified into two categories:
(1) heterogeneous catalysts, which are often deposited on a supporter, such as active carbon, silica, alumina, or calcium carbonate. The metal-contained heterogeneous catalysts are usually the compounds made by nickel, platinum, or palladium.
(2) homogenous catalysts, for example, (a) Ziegler-Natta catalysts composed of an organic salt of nickel, cobalt, iron, or chromium, and a reducing agent such as an organic aluminum compound, and (b) organometallic compounds containing one of Ru, Rh, Ti and La.
Although widely used in industry, heterogeneous catalysts have lower activity than the homogeneous catalyst. Therefore, in order to obtain the desired hydrogenation, a large amount of heterogeneous catalyst is required and the hydrogenation must be conducted at higher temperature and pressure. In contrast, the homogeneous catalysts are usually more active, a smaller amount of homogeneous catalysts is enough, and the hydrogenation can be conducted at mild temperature and pressure.
The hydrogenation method by using a heterogeneous catalyst is described as follows. First, the polymers to be hydrogenated are dissolved in a suitable solvent. Then, the polymers are brought into contact with hydrogen in the presence of a heterogeneous catalyst. When the polymers are hydrogenated, the viscosity of the polymers is quite high, and the contact between the polymers and the catalyst is difficult due to the interferences of the approach to the activation center by the steric hindrance of the polymers and the high absorption of the polymers, since the hydrogenated polymers tend to stay on the surface of the catalyst. Meanwhile, the hydrogenation requires higher temperature and pressure as the reactivity of the catalyst suddenly drops during the hydrogenation of the polymers, and therefore the decomposition of the polymers or the gelation of the reaction system tends to occur under such high temperature. Thus, under such operation conditions of the hydrogenation of the copolymers formed from the vinyl aromatic hydrocarbon monomers and the conjugated diene monomers, it is very difficult to selectively hydrogenate the double bonds in the conjugated diene portions. The reason is that the benzene rings in the vinyl aromatic units have been hydrogenated under such high temperature and high pressure. In addition, since the polymer is strongly adsorbed on the heterogeneous catalyst, it is impossible to completely remove the catalyst from the hydrogenated polymer solution.
In the Ziegler-Natta catalyst system, the hydrogenation reaction proceeds in the homogeneous mediums, so the hydrogenation reaction can be controlled under appropriate pressure and temperature. Thus, the hydrogenation reaction conditions can be selected to allow only the double bonds on the diene units to be hydrogenated without hydrogenating the aromatic rings on the vinyl aromatic units. However, the larger amount of the catalyst is still required. That is, the higher concentration of the catalyst is necessary. The catalyst can not be removed from the products easily, and the process of the catalyst removal is required for the post-treatment after the hydrogenation reaction, thereby making the product unstable and consuming the energy for removing the catalyst.
The conventional processes for the hydrogenation of conjugated diene polymers by using the homogeneous catalysts are summarized below.
U.S. Pat. No. 4,980,421 discloses a process for selectively hydrogenating a conjugated diene polymer by using the hydrogenation catalyst including a bis(cyclopentadienyl) titanium(+4) compound, an alkoxy lithium compound, and an organometallic compound (such as aluminum, zinc, or magnesium compound). This hydrogenation catalyst has high activity, and thus a small amount is required to reach the hydrogenation effect. Moreover, the deash process is not required and the reaction can proceed under mild conditions for this hydrogenation catalyst.
U.S. Pat. No. 5,270,274 discloses a hydrogenation catalyst composition including a bis(cyclopentadienyl) titanium(+4) compound, a compound containing polar carbonyl groups and epoxy groups, and an organic lithium compound. The unsaturated double bonds in the conjugated diene polymer can be preferentially hydrogenated. The hydrogenated polymers have superior physical properties and weathering resistance.
U.S. Pat. No. 5,244,980 discloses a hydrogenation process including terminating a living conjugated diene polymer with hydrogen and then adding an organo alkali metal and a Tebbe's catalyst, which has good hydrogenation efficiency is disclosed therein.
U.S. Pat. No. 5,886,108 discloses hydrogenating a living conjugated diene polymer introduced with hydroxyl, carbonyl or ester group by using the Tebbe's catalyst prepared by the reaction of a bis(cyclopentadienyl) titanium(+4) compound and trimethyl aluminum. This patent discloses that the hydrogenation efficiency is good when the mentioned compound is included in the reaction.
U.S. Pat. No. 5,985,995 discloses a catalyst composition. When a living conjugated diene polymer is combined with bis(cyclopentadienyl)Ti(PhOCH3)2 and alkyl silicon halide or alkyl tin halide. This patent discloses that the reaction reacted with the mentioned catalyst composition has very good hydrogenation efficiency.
U.S. Pat. No. 5,948,869 discloses a selective hydrogenation of unsaturated double bonds in conjugated diene polymers, where the catalyst composition includes a bis(cyclopentadienyl) titanium(+4) compound, an alkyl zinc or alkyl magnesium, and the promoter of the solvent with ether or aromatic groups. This patent discloses that the mentioned catalyst composition increases the hydrogenation efficiency obviously.
European Patent Appl. No. 0434469A2 discloses a catalyst composition for hydrogenating a conjugated diene polymer, where the catalyst composition includes a bis(cyclopentadienyl) titanium compound, an alkoxy alkali metal, and a polar compound of ether, ketone or other types. The catalyst system has capacities of hydrogenating conjugated diene polymers and the copolymers thereof.
European Patent Appl. No. 0544304A1 discloses a catalyst composition including (a) a bis(cyclopentadienyl) transition metal compound; (b) a polar compound containing carbonyl groups or epoxy groups such as esters of monoacids or diacids, internal ester, internal amide or epoxy; (c) an organic lithium compound; and (d) a reducing organometalic compound such as aluminum compound, zinc compound, or magnesium compound, for example, triethyl aluminum. This patent discloses that the mentioned catalyst composition increases the hydrogenation efficiency obviously.
U.S. Pat. No. 6,313,230 discloses the selective hydrogenation of the unsaturated double bonds of conjugated diene polymers, where the catalyst composition includes a bis(cyclopentadienyl) titanium(+4) compound and a tri-substituted silane with Si—H functional group. It is described that this catalyst composition can promote the hydrogenation efficiency. However, the silane contains hydrogen, thus tends to be hydrolyzed easily and reacted with oxygen or polar functional groups easily, and accordingly is hard to be stored at room temperature. In addition, from the embodiments of this patent, it is known that the highest reaction temperature is 60° C., the hydrogenation reaction cannot continuously proceed under high temperature, and the catalyst composition therein would deactivated under high temperature hydrogenation reaction. Thus a large amount of heat during the hydrogenation reaction must be removed; otherwise the hydrogenation efficiency will be low. This catalyst composition can not be stored under nitrogen gas for a long time, and the activity of the catalyst easily decays. The catalyst composition after the preparation must be used in short time; otherwise the hydrogenation rate can not be easily controlled. According, this catalyst composition is not suitable for the continuous manufacture.
According to the above descriptions, although many catalyst compositions had been used for hydrogenating a polymer formed by a conjugated diene, several problems of instability of the products and tedious procedures to remove the catalyst due to the large amount of the catalyst required. In order to solve the above-mentioned problems, after a lot of experiments and analyses, the research and development team of the present invention has developed novel hydrogenation methods with the catalyst compositions, which are stable and can be easily stored. In the present invention, only a small amount of the catalyst composition is needed, the removal of the catalyst from the hydrogenated compound is no longer required, and the polymers of conjugated dienes can be successfully hydrogenated. Moreover, the catalyst compositions of the present invention still have high catalysis activities at high temperature, and therefore are very suitable for the commercial mass production.

Hydrogenation catalyst composition and hydrogenation method thereof

Abstract: where R5 is C1˜C12 alkyl, alkenyl, amine, ether, ketone or ester groups, R3 and R6 are C1˜C12 alkyl or alkenyl groups, R4 and R7 are C1˜C12 alkyl, alkenyl, amine, ether, ketone or ester groups, n and m are integrals, 1≦n≦3, 1≦m≦3, and (c) alkyl aluminum.


A wireless communication network serves User Equipment (UEs) over a wireless network slice. A core user-plane in the slice exchanges user data with the UEs over a Radio Access Network (RAN). The core control-plane determines when the slice has a concentration of UEs that exceeds a threshold in a geographic area. When the slice has the UE concentration that exceeds the threshold in the geographic area, the core control-plane signals an edge user-plane to serve the UEs that use the wireless network slice in the geographic area. The edge user-plane exchanges additional user data over the RAN with the UEs that use the wireless network slice in the geographic area. The core control-plane may determine when the concentration of UEs moves toward another geographic area and proactively launch another edge user-plane to serve the UEs that will soon need the slice in the other geographic area.

Wireless communication networks provide wireless data services to wireless user devices. Exemplary wireless data services include machine-control, internet-access, media-streaming, and social-networking. Exemplary wireless user devices comprise phones, computers, vehicles, robots, and sensors. The wireless user devices execute user applications that use the wireless data services. For example, a smartphone may execute a social-networking application that communicates with a content server over a wireless communication network.
The wireless communication networks have wireless access nodes which exchange wireless signals with the wireless user devices over radio frequency bands. The wireless signals use wireless network protocols like Fifth Generation New Radio (5GNR), Long Term Evolution (LTE), Institute of Electrical and Electronic Engineers (IEEE) 802.11 (WIFI), and Low-Power Wide Area Network (LP-WAN). The wireless access nodes exchange network signaling and user data with network elements that are often clustered together into wireless network cores. The network elements comprise Access and Mobility Management Functions (AMFs), Session Management Functions (SMFs), User Plane Functions (UPFs), Application Server Functions (ASFs), and the like. Some network elements like UPFs and ASFs are grouped into wireless network slices. An individual wireless user device may request a specific wireless network slice.
Although the network elements are concentrated in the wireless network cores, new network elements are often deployed at the wireless network edge that is near the wireless access nodes. Thus, some wireless user devices interact with the network elements at the network edge instead of the network elements in the network core. Unfortunately, the wireless network slices ineffectively use the edge network elements. Moreover, the wireless network slices inefficiently use the edge network elements given the location and movement of the wireless user devices.

Wireless communication service over a wireless network slice based on user equipment (UE) concentrations


An outdoor swivel head spotlight is described. A light bulb hood comprises a reflector and base. The base comprises a spherical socket having an internal seat. A support arm comprising a spherical end and a distal end connected to the spherical end by a through conduit is provided. The spherical end is seated in the internal seat. An internally threaded nut comprising an inwardly projecting lip having an open interior diameter at least as large as the external diameter of the spherical end, is coupled with the spherical socket. A washer between the spherical end and the lip of the nut is provided. When the nut is in a loosened position, the hood may be positioned to a desired angular position and when the nut is in a tightened position, the washer presses the spherical end into the internal seat to fix the angular position of the light hood.

1. Technical Field
Aspects of this document relate generally to outdoor spotlights having swivel heads.
2. Background Art
Outdoor spotlights are commonly used in many residential, commercial and industrial applications in order to provide illumination where desired. Outdoor spotlights are desirably weatherproof and resist water entry into the housing. Conventional outdoor spotlights having a light bulb hood may require multiple adjustments of a light bulb hood in order to adjust the direction of the light bulb hood separately in multiple axes.


Disclosed herein is a composition comprising: a flame retardant comprising a sulfonate salt and three polycarbonates. The first polycarbonate has a branching level of greater than or equal to 2%, a weight average molecular weight of 20,000 g/mole to 55,000 g/mole and a peak melt viscosity of greater than or equal to 25,000 poise. The second polycarbonate has a glass transition temperature greater than or equal to 170° C. The third polycarbonate has a branching level of 0 to less than 2% and a molecular weight of 17,000 to 40,000 g/mol. The composition has a heat distortion temperature greater than or equal to 145° C., ductility greater than or equal to 90% at 23° C., multi-axial impact greater than or equal to 50 Joules per meter (J/m) at 23° C., and a molded article of the composition has a UL 94 V0 rating at a thickness of 1.5 mm.

Polycarbonate is a high-performance plastic with good impact strength (ductility). However, polycarbonate often has relatively limited flow properties, which is needed in the manufacture of thin walled articles. Medium to high flow polycarbonate grades suffer from the fact that the ductility is sacrificed for a better flow. Furthermore, it becomes difficult to combine adequate ductility with a high glass transition temperature, impact strength and flame retardance (particularly at thicknesses of 1.5 millimeters or less).
There accordingly remains a need in the art for high flow polycarbonate compositions and articles made therefrom that combine adequate ductility with a high glass transition temperature, impact strength and flame retardance.

Compositions and articles of manufacture containing branched polycarbonate


A semiconductor single crystal manufacturing apparatus which can manufacture a single crystal of high oxygen concentration to that of low oxygen concentration within a prescribed standard range of oxygen concentration, as a wafer material for semiconductor integrated circuits, with a high yield, is provided. Heat shields 20, 21 are provided in the entire annular area between respective adjacent heaters of the heaters 4a, 4b, 4c for heating the crucible 3 from the outside periphery side. By using the heat shields 20, 21 for localizing the respective heating regions for the heaters to actively control the temperature distribution for the crucible 3 and melt 8 in the crucible, a single crystal of high oxygen concentration to that of low oxygen concentration can be manufactured within a prescribed standard range of oxygen concentration with a high yield.

For semiconductor integrated circuits, a silicon wafer having a prescribed oxygen concentration is required to provide a protection against heavy metal contamination or to improve the various types of quality and the yield, and the silicon single crystal, which is a material for such a silicon wafer, can be manufactured with a single crystal manufacturing apparatus using the Czochralski method (hereinafter referred to as CZ apparatus).
With this CZ apparatus, a raw material for single crystal is filled into a crucible disposed inside a chamber, and inert purge gas is introduced into the chamber, while this raw material is heated and melted with a heater provided outside the crucible. After a seed crystal having thoroughly stuck into this molten melt, the seed crystal is pulled up, while being rotated, in order to grow a single crystal at the lower end of the seed crystal.
Most of the amount of oxygen in the silicon single crystal manufactured by using the above-mentioned CZ apparatus is supplied from the quartz used as the material for the crucible.
In other words, at a contact surface where the silicon melt and the inside surface of the crucible are contacted with each other at high temperature, the quartz (SiO2) in the crucible material always reacts with the silicon (Si) in the melt, and from the crucible surface, volatile silicon oxide (SiO) is eluted into the melt as eluted oxygen. This eluted oxygen is evaporated from the melt surface as volatile SiO, while the eluted oxygen is stirred by the forced convection of the melt due to the rotation of the crucible, the thermal convection due to the temperature distribution in the crucible and the melt in the crucible (hereinafter referred to as temperature distribution in crucible), and the like, a part thereof being transported to the growth interface of the single crystal which is being pulled up, and taken into the single crystal.
By the way, during actual manufacture of the silicon single crystal, the amount of oxygen taken in into the single crystal is complicatedly relates to various manufacturing conditions, such as the SiO reaction speed, the purge gas conditions, the remaining amount of the melt, the heating conditions of the heater, and the like, thus it is considerably difficult to manufacture the single crystal within a prescribed oxygen concentration with a high yield.
Then, conventionally, as the method for controlling the oxygen concentration in a silicon single crystal, the method which pays attention to the relation between the rotational speed of the crucible and the oxygen concentration in the melt; the method which heeds the relation between the pressure, flow rate, flow velocity conditions of the purge gas and the amount of evaporated SiO; the method which pays heed to the applied magnetic field in the crucible and the oxygen concentration in the melt; and the like, have been proposed and implemented.
Further, in the patent literatures 1 to 4, as a promising method for controlling the oxygen concentration that can replace the above-mentioned methods, the method and the apparatus, as outlined below, which use a plurality of heaters to control the above mentioned "temperature distribution in crucible", thereby controlling the oxygen concentration in the silicon single crystal being pulled up, is disclosed.
Patent literature 1 discloses an apparatus wherein a plurality of heaters are vertically provided in steps along the side periphery of the crucible, and according to the state of progress of single crystal pulling up, electric power is appropriately supplied to each of these heaters, whereby the amount of eluted oxygen and the oxygen elution region are appropriately controlled to hold the oxygen concentration in the single crystal to within a prescribed range. This method features that, during the first half of the single crystal manufacturing process, the melt at the crucible bottom is solidified for a while to control the amount of eluted oxygen from the bottom of the crucible.
Patent literature 2 discloses a method for manufacturing the single crystal having the targeted oxygen concentration with a high yield through suppressing the amount of eluted oxygen at the crucible bottom, by vertically providing a plurality of heaters in steps along the side periphery of the crucible, and maintaining the level of the surface of the melt to within the heating region for the top heater, while setting the ratio of the output of the top heater to that of all the heaters at a prescribed value or higher, and always holding the temperature at the crucible bottom to below the temperature at the crucible upper portion.
Patent literature 3 discloses a method of manufacturing the single crystal using an apparatus having a shield member for finely controlling the oxygen concentration in the single crystal silicon, by independently controlling the outputs of a plurality of heaters provided along the side periphery and the bottom of the crucible, thereby suppressing the high temperature region in the melt from being shifted toward the high temperature side by the above-mentioned shield member.
Patent literature 4 discloses an invention for controlling the oxygen concentration in the silicon single crystal by vertically providing heaters at three-stages along the side of the quartz crucible, varying the electrical resistance for the respective heaters, and supplying electric power to the respective heaters from a common power supply, thereby varying the amount of heat generated in the respective heaters.    Patent literature 1: Japanese Patent Application Laid-Open No. 62-153191    Patent literature 2: Japanese Patent No. 3000923    Patent literature 3: Japanese Patent No. 2681115    Patent literature 4: Japanese Patent Application Laid-Open No. 2001-39792

Semiconductor single crystal manufacturing apparatus and graphite crucible


The invention relates to a method for tilting of the car body in track curves on a railbound vehicle, the tilting of the car body being achieved by means of hydraulic cylinders and the tilting being adapted to be controlled by one or more servo functions. According to the invention, the car body tilt is adapted to be limited to a maximum value, and when snow occurs, which is packed between the different parts of the tilting system, the degree of snow packing is indicated, and when a certain degree of snow packing is exceeded, the desired value of the tilt angle is maximized to a suitable smaller value.

One example of an arrangement for tilting of the car body is disclosed in Swedish patent application 8902526-6, in which the hydraulic cylinders are arranged mutually communicating and the tilting of the car body is adapted to be controlled by a servo function comprising one servo function per vehicle.
In a vehicle with tilting of the car body, for example as described above, the desired value of the tilting is normally formed with the aid of the lateral acceleration. To avoid a great tilting movement, this is often limited to a maximum value. Under winter conditions, snow which is packed between the movable parts of the tilting system may prevent the tilting movement, which, in turn, may lead to unfavourable wheel unload and uncomfortable ride. Without taking special measures such snow packing in the tilting system will result in great control errors and forces.

Indication of snow packing for railway vehicles


A magnetic head assembly according to one embodiment of the present invention includes a substrate having a tape bearing surface. A plurality of elements are coupled to the substrate and positioned towards the tape bearing surface. The elements selected from a group consisting of readers, writers, and combinations thereof. A base is coupled to the substrate. The base has an outrigger formed integrally therewith. The outrigger causes a tape passing thereacross to approach the substrate at a first wrap angle relative to a plane of the tape bearing surface of the substrate.

FIG. 1 illustrates a traditional flat-lapped bi-directional, two-module magnetic tape head 100, in accordance with the prior art. As shown, the head includes a pair of bases 102, each equipped with a module 104. The bases are typically ceramic beams shaped in the form of a U that are adhesively coupled together. Each module 104 includes a substrate 104A and a closure 104B with readers and writers 106 situated therebetween. In use, a tape 108 is moved over the modules 104 along a tape bearing surface 109 in the manner shown for reading and writing data on the tape 108 using the readers and writers 106. Conventionally, a partial vacuum is formed between the tape 108 and the tape bearing surface 109 for maintaining the tape 108 in close proximity with the readers and writers 106.
Two common parameters are associated with heads of such design. One parameter includes the tape wrap angles αi, αo defined between the tape 108 and a plane 111 in which the upper surface of the tape bearing surface 109 resides. It should be noted that the tape wrap angles αi, αo includes an inner wrap angle αi which is often similar in degree to an external, or outer, wrap angle αo. The tape bearing surfaces 109 of the modules 104 are set at a predetermined angle from each other such that the desired inner wrap angle αi is achieved at the facing edges. Moreover, a tape bearing surface length 112 is defined as the distance (in the direction of tape travel) between edges of the tape bearing surface 109. The wrap angles αi, αo and tape bearing surface 112 are often adjusted to deal with various operational aspects of heads such as that of FIG. 1.
FIG. 2A is an enlarged view of the area encircled in FIG. 1. During use of the head of FIG. 1, various effects traditionally occur. With reference to FIG. 2A, a first known effect associated with the use of the head 100 is that when the tape 108 moves across the head as shown, air is skived from below the tape 108 by a skiving edge 204 of the substrate 104A. Instead of the tape 108 lifting from the tape bearing surface 109 of the module (as intuitively it should), the reduced air pressure in the area between the tape 108 and the tape bearing surface 109 allows atmospheric pressure to urge the tape towards the tape bearing surface 109.
To obtain this desirable effect, the wrap angle αo is carefully selected. An illustrative wrap angle is about 0.9°±0.2. Note, however, that any wrap angle greater than 0° results in tents 202 being formed in the tape 108 on opposite edges of the tape bearing surface 109. This effect is a function of tape stiffness and tension. For given geometrical wrap angles for example, stiffer tapes will have larger tents 202.
If the wrap angle αi, αo is too high, the tape 108 will tend to lift from the tape bearing surface 109 in spite of the vacuum. The larger the wrap angle, the larger the tent 202, and consequently the more air is allowed to enter between the tape bearing surface 109 and tape 108. Ultimately, the forces (atmospheric pressure) urging the tape 108 towards the tape bearing surface 109 are overcome and the tape 108 becomes detached from the tape bearing surface 109.
As shown in FIG. 2B, if the wrap angle αi, αo is too small, the tape tends to exhibit tape lifting 205, or curling, along the side edge of the tape bearing surface 109. This is a result of air leaking in at the edges and tape mechanical effects. Particularly, the edges of the tape tend to curl away from the tape bearing surface 109, resulting in edge loss or increased spacing between the edges of the tape and the tape bearing surface 109. This is undesirable, as data cannot reliably be written to the edges of a tape in a system subject to edge loss.
Additionally, the tape lifting 205 results in additional stress at points 206 which, in turn, may cause additional wear of the head. Further augmenting such tape lifting 205 is the fact that the tape 108 naturally has upturned edges due to widespread use of technology applied in the video tape arts.
The external wrap angles αo are typically set in the drive, such as by rollers. The offset axis creates an orbital arc of rotation, allowing precise alignment of the wrap angle αo. However, situations arise where rollers may not be the most desirable choice to set the external wrap angles αo. For example, rollers require extra headroom in a drive, particularly where they are adjustable. Additionally, rollers, and particularly adjustable roller systems, may be more expensive to install in the drive. A further drawback of this approach is mechanical alignment cannot be completed independent of signal read readiness.
FIG. 3 illustrates one proposed solution to set the desired external wrap angles αo, and which may be less expensive than implementing adjustable rollers. The proposed solution comprises forming outriggers 150 on the module 104, as shown in FIG. 3. The outriggers 150 set the external wrap angles αo. However, as the fabrication of tape head components moves towards use of thinner wafers, the distance between the front and back faces of the module 104 is reduced. When outriggers 150 are used, a minimum free space span between the outrigger inner edge 152 and the outer edge 154 of the primary tape bearing surface 109 is required to compensate for the aforementioned tape effect, namely tenting. Particularly, in a flat-profile tape head (as shown), the elements 106 are positioned between the substrate 104A and a closure 104B. The primary tape bearing surface 109 needs to be long enough in the direction of tape travel so that tenting does not occur over the elements 106, because reliability of the read/write functions depends in part on the tape-head spacing.
Because of the requisite length of the primary tape bearing surface 109, in combination with the fact that the bending moment of the tape propagates out from the outrigger, the distance between the outer edge 154 of the primary tape bearing surface and the back end 158 of the substrate 104A becomes too small to accommodate an outrigger. Accordingly, it will not be possible to create and outrigger on the same substrate on which the transducers are formed in the next generation of heads.
Another difficulty created by the reduced span is that the height of the outrigger must be kept to a very tight tolerance to maintain the proper wrap angle, as the shorter distance between outrigger and primary tape bearing surface means there is less room for deviation.
There is accordingly a clearly-felt need in the art for a tape head assembly in which the critical wrap angles are fixed on the head assembly itself. There is also a clearly-felt need for a way to provide an outrigger on a tape head assembly of small proportions.

International Business Machines Corporation


Disclosed is an ultra wide band signal generator. The ultra wide band signal generator generates a signal of a required frequency using a harmonic signal having a frequency range of a ultra wide band (UWB). The ultra wide band signal generator includes an active inductor for generating harmonic signals having power strengths substantially equal to each other within a non-linear operation range, the tunable active inductor capable of tuning a value thereof, an oscillator for amplifying and outputting the harmonic signals generated from the active inductor by frequency-transiting the harmonic signals into high frequency bands, and a filter for selectively outputting one of the harmonic signals output from the oscillator.

1. Field of the Invention
The present invention relates to a signal generator, and more particularly to a signal generator for generating a signal at a required frequency using a harmonic signal having a frequency range in the ultra wide band (UWB).
2. Description of the Related Art
In a wireless communication system, a radio frequency (RF) signal received in a receiver is converted into an intermediate frequency (IF) signal by means of a mixer 10 as shown in FIG. 1. The mixer 10 mixes a signal delivered from a voltage controlled oscillator (VCO) 12 with the RF signal and converts the frequency of the mixed signal into the frequency of the IF signal.
As described above, the VCO included in the receiver is mainly used for channel selection. In order to be used for band selection, the VCO must have a wider frequency control range.
However, the conventional VCO shown in FIG. 2 cannot control a wide frequency range using only a varactor because a great number of parasitic capacitors exist in the VCO.
As shown in FIG. 3, a non-linear element generates harmonics with respect to a fundamental frequency f, and these harmonics are generated in a wide frequency band. Since these harmonics have very little power, the harmonics are unsuitable for oscillator signals.


The liquid crystal display device of the present invention is a liquid crystal display device where a light source (160) is disposed on the inner periphery of a liquid crystal module (100), which has a metal front frame (110) and a metal back cover (120), which constitute the housing of the liquid crystal module (100), and a conductive upper case (140) which is laid between a liquid crystal panel (130) and the light source (160) and has a frame having approximately the same shape as that of the front frame 110, in which perforated joints, which are bent vertically and integrally formed on the outer end portions of the front frame, the outer end portions of the upper case (140) and the outer end portions of the back cover (120) are severally provided at positions overlapping with each other when the liquid crystal module (100) is assembled, and the joints (143) of the upper case (140) are sandwiched between the joints (112) of the front frame and the joints (123) of the back cover (120) in order to make the joints attachable to each other with the aid of screws (190) with a foot length less than the width of the front frame. A liquid crystal display device is thereby obtained according to the present invention, in which highly reliable ground connection is realized even when used in an environment subject to frequent vibration.

1. Field of the Invention
The present invention relates to a liquid crystal display device, particularly to a liquid crystal display device having high definition display and capable of realizing secure ground connection even when used in an environment subject to frequent vibration.
2. Background Art
Conventionally, it has been known that noise generated from the cold cathode tube of a backlight arranged on the backside of a liquid crystal panel adversely affects the display quality of the liquid crystal panel. A technique designed to address this problem has been disclosed in Japanese Patent Laid-Open Publication No. 2001-75485 pertaining to a flat display device, where the member (shield member) having electrical conductivity is arranged around a cold cathode tube, the electrically conductive member being connected to a front frame (bezel cover) to reduce noise.
In addition, Japanese Patent Laid-Open Publication No. 11-183926 pertaining to an attachment structure of foil-state earth wire for a liquid crystal display device, Japanese Patent Laid-Open Publication No. 2001-305971 pertaining to a display device, as well as Japanese Patent Laid-Open Publication No. 2003-15150 pertaining to a liquid crystal panel electrically conductive connection structure, have also been introduced to address such problem. However, the conventional technique is beset with problems.
Specifically, if connection between the shield member and the front frame or the like was in a simple contact state, the connection becomes unstable due to impact or vibration, affecting display quality. Particularly, when the liquid cystal display device is used in an environment subject to frequent vibration or to which impact is easily applied, a joint portion of the device becomes fatigued upon prolonged use depending on the connecting material or connecting mode, resulting in a change in ground pressure change or contact failure.
Further, while the liquid crystal display device has an advantage over the CRT display device because its housing is smaller than that of the latter, problems arise when it is mounted on certain products. For example, the device is required to be as small as possible, keeping the display area fixed and limiting the number of convex portions provided on the housing to as few as possible in order to allow greater freedom in product design.
However, in the technique disclosed in Japanese Patent Laid-Open Publication Nos. 11-183926 and 2001-305971, convex portions are provided on the periphery of the housing and the housing is grounded from a convex portion. Further, while convex portions are not similarly provided in the technique disclosed in Japanese Patent Laid-Open Publication No. 2003-15150, the housing has a special clamped structure, thereby increasing the thickness of the housing. Further, in the technique disclosed in Japanese Patent Laid-Open Publication Nos. 2001-75485 and 2003-15150, a special grounding member is used, which decreases efficiency of the assembly operation, causing increased production cost.

Liquid crystal display device with perforated joint pieces attachable by screws


A boron carbide based sintered body having a four-point flexural strength of at least 400 MPa and a fracture toughness of at least 2.8 MPa·m1/2, which has the following two preferred embodiments. (1) A boron carbide-titanium diboride sintered body obtained by sintering a mixed powder of a B4C powder, a TiO2 powder and a C powder while reacting them under a pressurized condition and comprising from 95 to 70 mol % of boron carbide and from 5 to 30 mol % of titanium diboride, wherein the boron carbide has a maximum particle diameter of at most 5 μm. (2) A boron carbide-chromium diboride sintered body containing from 10 to 25 mol % of CrB2 in B4C, wherein the sintered body has a relative density of at least 90%, boron carbide particles in the sintered body have a maximum particle diameter of at most 100 μm, and the abundance ratio (area ratio) of boron carbide particles of from 10 to 100 μm to boron carbide particles having a particle diameter of at most 5 μm, is from 0.02 to 0.6.

In general, a boron carbide sintered body is expected to have a wide range of applications as a material having a light weight and high hardness and being excellent in abrasion resistance or corrosion resistance. At present, it is used, for example, for a sandblast nozzle, a wire drawing die or an extrusion die. However, on the other hand, such a boron carbide sintered body has a drawback that it has low strength. For example, K. A. Schwetz, J. Solid State Chemistry, 133, 177-81 (1997) discloses preparation of boron carbide sintered bodies by HIP treatment under various sintering conditions, but a boron carbide sintered body having a flexural strength of at least 600 MPa has not yet been obtained.
Further, V. Skorokhod, J. Material Science Letter, 19, 237-239 (2000) discloses that a mixture comprising a boron carbide (B4C) powder, a titanium dioxide (TiO2) powder and a carbon (C) powder, is sintered under a pressurized condition employing a hot press method while reacting a part of boron carbide with titanium dioxide and carbon (see the following reaction formula), to obtain a boron carbide-titanium diboride sintered body, whereby a four-point flexural strength of 621 MPa is obtained.Reaction formula: B4C+2TiO2+3C→2TiB2+4CO
However, in order to make it practically possible to use a boron carbide based sintered body in a wide range of applications, it is desired to develop a boron carbide based sintered body having a still higher four-point flexural strength. However, as mentioned above, according to the conventional methods, a boron carbide based sintered body having a high four-point flexural strength exceeding 621 MPa has not yet been obtained.
Further, a boron carbide based sintered body is hardly sinterable and accordingly, it is usually prepared by a hot press method. This production method hinders a common application of a boron carbide based sintered body, since its production cost is high. Accordingly, it is being studied to prepare a boron carbide sintered body by heating (sintering) under a non-pressurized condition (a normal pressure method) instead of the hot press method. For example, in the above-mentioned prior art reference K. A. Schwetz, J. Solid State Chemistry, 133, 177-81 (1997), carbon is added as a sintering-assisting agent, and a boron carbide sintered body is prepared under a non-pressurized condition. However, such a method is not practically preferred, since it is necessary to carry out sintering at an extremely high temperature of at least 2150° C.
Further, a boron carbide sintered body has an extremely high hardness, whereby it can hardly be processed by a usual grinding/polishing method, and further, the electric conductivity of the boron carbide sintered body is low at a level of from 10 to 300 S/m, whereby there has been a problem that the discharge processing is difficult.
As mentioned above, a boron carbide sintered body is hardly sinterable and hardly processable, and at present, it is practically used only in an extremely limited application.
Under these circumstances, the present inventors have conducted an extensive research with an aim to develop a new boron carbide based sintered body which has a four-point flexural strength higher than the above-mentioned four-point flexural strength of 621 MPa and which makes it possible to realize a wide range of applications, and as a result, have found it possible to accomplish the desired object by selecting a specific material and by carrying out sintering treatment with a specific composition and under a specific temperature condition.
Further, the present inventors have found it possible to obtain a boron carbide based sintered body having excellent characteristics by preparing a sintered body having a specific microstructure wherein a highly electrically conductive chromium diboride phase forms a three dimensional network structure, by adding a predetermined amount of chromium diboride to a boron carbide powder having a specific physical property and carrying out liquid phase sintering under a non-pressurized condition to form a liquid phase of chromium diboride.
The present invention has been accomplished on the basis of the above discoveries.
Namely, it is an object of the present invention to provide a novel boron carbide based sintered body having a four-point flexural strength of at least 400 MPa and a fracture toughness of at least 2.8 MPa·m1/2.
Further, it is an object of the present invention to provide a boron carbide-titanium diboride sintered body having a four-point flexural strength of at least 700 MPa, preferably at least 800 MPa and a fracture toughness of at least 3.0 MPa·m1/2.
Further, it is an object of the present invention to provide a novel process for producing a boron carbide material which makes it possible to produce a boron carbide based sintered body which has a high density and having the fracture toughness improved, wherein the maximum particle diameter of boron carbide is at most 5 μm, the titanium diboride particles are uniformly dispersed in the boron carbide matrix, and the agglomerated/dispersed state of titanium diboride particles is uniform and good.
Further, it is an object of the present invention to provide a boron carbide based sintered body which has a relative density of at least 90%, an electrical conductivity of at least 5×102 S/m, a four-point flexural strength of at least 400 MPa and a fracture toughness of at least 3.0 MPa·m1/2, and a process for producing it by sintering under a non-pressurized condition.

Boron carbide based sintered compact and method for preparation thereof

National Institute of Advanced Industrial Science and Technology


A method of providing current mode pulse frequency modulation (PFM) for a switching regulator can include resetting a driver input for a fixed duration when a first current in the driver reaches a first value set by an error amplifier output. The first current can be associated with PMOS switching transistors in the driver. The method can also include setting the driver input signal for the same fixed duration when a second current in the driver reaches a second value. This second current can be associated with NMOS switching transistors in the driver. In one embodiment, the driver can be tristated to ignore both the resetting and the setting. Using this method, perturbations of the inductor current can be substantially corrected and have limited impact on the current waveform beyond the cycle in which they occur.

Switching regulators can be used to convert an unregulated voltage to a desired, regulated DC voltage. FIG. 1 illustrates a schematic of a simple switching regulator 100 including an error amplifier 101 (e.g. a gm amplifier or another amplifier having a high output impedance), a modulator 102, a switching element 103, an LC filter 104, a load 105, and a compensation circuit 106.
In switching regulator 100, modulator 102 drives switching element 103 to provide one of VDD or VSS to LC filter 104. Specifically, a PMOS transistor 103A of switching element 103 is turned on (and an NMOS transistor 103B is turned off) to couple VDD to the input of inductor L of LC filter 104, thereby generating a ramped current through that inductor. At another point in time, NMOS transistor 103B is turned on (and PMOS transistor 103A is turned off) to couple VSS to the input of inductor L, thereby causing the current to ramp down until the start of a new switching cycle.
The amount of time that switching element 103 is "on" (i.e. PMOS transistor 103A being turned on) versus the total period is called the duty cycle. The duty cycle determines the output voltage Vout at a particular load current. Note that the capacitor C and the inductor L of LC filter 104 are sized to reduce voltage ripple of Vout. Load 105 is shown as a resistor R for purposes of illustration.
Error amplifier 101 receives voltage Vout on its negative input terminal and a reference voltage REF on its positive input terminal. Compensation circuit 106, which includes a resistor and a capacitor in this embodiment, is connected to the output terminal of error amplifier 101. In this configuration, error amplifier 101 can modify its output based on the difference between voltage Vout and reference voltage REF. The output of error amplifier 101 is provided to modulator 102, which can change the duty cycle of switching element 103 to minimize such difference.
There are numerous challenges in switching regulator design. The most basic challenge is obtaining a stable frequency response without undue restriction on external inductor and capacitor types/values (i.e. with respect to LC filter 104). This problem arises because LC filter 104 has two potentially low frequency poles (provided by inductor L and capacitor C) well below the unity gain bandwidth of switching regulator 100. Notably, if error amplifier 101 provides high gain, as can the case when using voltage mode pulse width modulation (PWM) for switching regulator 100, then error amplifier 101 introduces yet another low frequency pole.
To compensate for the three low frequency poles, a designer must include at least two zeros wherein compensation circuit 106 provides only one zero (via the resistor and capacitor therein). In one embodiment, the second zero can be designed into a more complex error amplifier 101. Alternatively, the designer can rely on the ESR (equivalent series resistance) of capacitor C in LC filter 104 to introduce the second zero (note that the capacitor C actually includes some parasitic resistance, which at some high frequency provides an additional zero). This option is simpler than designing a new error amplifier, but places restrictions on the type of capacitor that can be used by a customer in LC filter 104. If the customer fails to adhere to such restrictions, the loss and output ripple of switching regulator 100 may undesirably increase. Further, the wrong type of capacitor in LC filter 104 can even cause regulator instability.
Current mode PWM was developed to simplify switching regulator loop dynamics. FIG. 2 illustrates a switching regulator 200 using current mode PWM (note that elements having an identical or substantially identical function are labeled with the same reference numbers). In current mode PWM, switching regulator 200 uses a current loop 201 to control the inductor current and a voltage loop 202 to control the output voltage (described in reference to switching regulator 100 in FIG. 1).
In this embodiment, the inductor current is sensed with a small resistor Rsense and a current sense amplifier 203 having input terminals connected to both terminals of resistor Rsense. The output terminal of current sense amplifier 203 is connected to a negative input terminal of a PWM comparator 204 via current loop 201. The positive input terminal of PWM comparator 204 is coupled to the output terminal of error amplifier 101 via a summing block 208 (described in further detail below). The output terminal of PWM comparator 204 is connected to a reset terminal of a set/reset circuit 205. A set terminal of set/reset circuit 205 receives an oscillator signal 206. The output terminal of set/reset circuit 205 is buffered by a driver 207, which has an output terminal connected to resistor Rsense. Note that driver 207 can perform the functions associated with switching element 103 (FIG. 1), whereas PWM comparator 204, set/reset circuit 205, current sense amplifier 203, and resistor Rsense can perform the functions associated with modulator 102.
In this configuration, set/reset circuit 205 sets the PWM output periodically (using oscillator signal 206) and only resets the PWM output when the peak inductor current reaches a value set by voltage loop 202. Because the inductor current can be effectively controlled, the inductor current does not play a role in the loop dynamics. Therefore, from a small signal perspective, the inductor current can be replaced with a transconductance equal to 1/Rsense. As a result, good phase margin can be achieved with a single compensating zero and the ESR of capacitor C (in LC filter 104) is not restricted.
Unfortunately, current mode PWM suffers from an additional problem. Specifically, current loop 201 is unstable if the PWM duty cycle is greater than 50%. The duty cycle is determined by the regulator input voltage, output voltage Vout, and to a lesser extent the amount of power delivered to load 105. For duty cycles greater than 50%, the instability of current loop 201 can cause an undesirable sub-harmonic oscillation in the PWM and output voltage waveforms.
A technique called slope compensation was developed to mitigate this sub-harmonic oscillation. In switching regulator 200, summing block 208 can perform such slope compensation by introducing a periodic saw-tooth waveform to the output of error amplifier 101 (and thus to the input of PWM comparator 204). If the slope of the saw-tooth waveform is set properly, then inner loop 201 can be critically damped so that perturbations of the inductor current are corrected within a single cycle.
The correct slope for critical damping depends on the derivative of the inductor discharge current, which in turn depends on the output voltage Vout and the inductance L. That is, slope compensation works best if the slope of the saw-tooth waveform matches a value that depends on the output voltage Vout of inductor L. This matching requirement can place undesirable restrictions on both the output voltage Vout and the inductance L for a given switch regulator design. Moreover, to produce a saw-tooth waveform (and other necessary waveforms at appropriate points in the rest of the control circuit, not described herein), current mode PWM may require the design of complicated circuitry, e.g. summing block 208.
Note that if the slope compensation of summing block 208 is not set properly, then many cycles of oscillator 206 may be required for transients (i.e. current perturbations) to settle. Because of these additional cycles, voltage loop 202 must have a lower bandwidth than otherwise necessary.
Therefore, a need arises for a switching regulator that simplifies switching regulator loop dynamics without the need for slope compensation and without restrictions on output voltage and external components.

Current mode pulse frequency modulation switching regulator


A box-spring core has a first group of first chains extending spacedly adjacent and parallel to one another and a second group of second chains extending adjacent and parallel to one another and transversely of the first chains. Each of the chains has an elongated flexible sheath formed with a plurality of longitudinally spaced, transversely extending, and through-going slits that are each transversely aligned with the slits of adjacent sheaths, a transverse seam adjacent each slit and internally subdividing the respective sheath into a respective succession of longitudinally spaced pockets, and respective springs in the respective pockets each compressible in a transverse direction parallel to the slits. The springs have opposite ends lying generally in respective parallel planes. Each slit has a predetermined length measured perpendicularly between the planes and the combined lengths of a pair of interfitting slits are generally equal to the predetermined height.

Such boxed spring cores are known for example from EP 154,076. Here parallel chains are connected together by means of glue. Box spring cores are further known from the state of the art wherein a mechanical connection is formed by throughgoing connecting filaments.
The use of glue is disadvantageous in that on the one hand it requires the use of an additional material, the glue, and on the other hand applying devices for the glue must be provided and time must be set aside for curing of the glue. In the hitherto known mechanical connection systems a substantial amount of equipment is necessary, and in addition the use of connecting filaments is disadvantageous both during manufacture and during further handling.

Box spring core with compartmentalized springs


Disclosed herein are systems for shaping a glass sheet comprising a roll conveyor comprising a plurality of rollers for conveying the glass sheet along a plane; a lift jet array comprising a plurality of nozzles, one or more of the plurality of nozzles comprising a tip having a plurality of orifices; and a shaping mold located above the roll conveyor, wherein the lift jet array is positioned below the roll conveyor such that each nozzle tip is located above the centerline of the plurality of rollers. Also disclosed herein are methods for shaping a glass sheet comprising heating the glass sheet and conveying the glass sheet on a roll conveyor to a position between the lift jet array and the shaping mold, wherein gas flows from the lift jet array with a force sufficient to lift the glass sheet from the roll conveyor.

The ability to thermally shape and form thin glass sheets is increasingly relevant to various industries, such as the automotive industry. The production of glass panes for automobiles is a complex process, which is constantly changing due to increasingly stringent environmental and safety requirements. The demand for intricate glass shapes with high optical quality and low weight is growing as governmental regulations require increased fuel economy and reduced emissions. The ability to make automotive parts from thinner glasses may translate to lower vehicle weight, improved fuel economy, reduced emissions, and/or improved vehicle weight distribution (e.g., lower center of gravity).
Prior art methods for shaping glass include placing glass sheets on a roll conveyor, conveying the glass through a furnace to heat and soften the sheets, and positioning the softened glass below a shaping mold, where it is lifted upward by a lift jet array to contact the shaping mold. The shaping mold serves as a surface around which the glass sheet can be formed to the desired shape. The lift jet array pattern is typically different for different shapes and/or parts and may include non-adjustable, fixed diameter/orifice nozzles and/or adjustable threaded nozzles. The nozzles are positioned below the rollers and blow controlled and focused streams of heated air up between the rollers.
Conventional lift jet systems work well with traditional glasses, which are thicker, such as soda-lime glasses having a thickness ranging from about 3 mm to about 6 mm. Thicker glass sheets can generally withstand the pressure from the nozzles without suffering from local deformations. However, when thinner glasses (e.g., thicknesses less than about 3.0 mm, between about 0.3 mm and about 2.0 mm, between about 0.5 mm and about 1.5 mm, and all ranges and subranges therebetween) are processed using these traditional lift jet systems, the glass tends to distort and bend between each nozzle due to the localized upward force from the nozzles.
Accordingly, it would be advantageous to provide methods and systems for shaping and tempering thinner glass sheets, more specifically a lift jet array that more evenly distributes the upward lifting force over a greater surface area so as to reduce and/or eliminate glass distortion. To reduce manufacturing costs and/or processing times, it would additionally be advantageous to provide a system that can function, at least in part, in conjunction with existing systems for bending and tempering traditional (e.g., thicker) glasses.

Method and lift jet floatation system for shaping thin glass


A machine for shredding a discarded tire is composed of a base, a vertical advancing seat, a horizontal advancing seat, a tire holding device, a transmission device, a tool set, and a computer control device. The vertical advancing seat is provided with a slide block capable of sliding along the vertical advancing seat in the vertical direction relative to the base. The horizontal advancing seat is mounted on the slide block of the vertical advancing seat and is provided with a slide block capable of sliding along the horizontal advancing seat in the horizontal direction relative to the base. The horizontal advancing seat is further provided with two sensors, whereas the slide block of the horizontal advancing seat is provided with two sensing blocks capable of cooperating with the sensors to execute the step-by-step shredding operation is conjunction with the tool set and the computer control device.

The discarded tire is a serious environmental problem in view of the fact that the discarded tire can not be easily disposed of, and that the discarded tire is one of the sources responsible for the environmental pollution. The practical and workable solution to environmental problem caused by the discarded tire is to recycle the discarded tire. However, before the discarded tire is recycled, it must be shredded in a specific manner to conform with the recycling requirements. The conventional shredding machines are not specifically intended for shredding the discarded solid tire for the recycling purpose. For this reason, there is indeed a need for developing a machine for shredding the discarded solid tire for the recycling purpose.


Methods and apparatus for forming conductive interconnect layers useful in articles such as semiconductor chips, memory devices, semiconductor dies, circuit modules, and electronic systems. An electrochemical cell may be used in the reduction of oxides on a dual-purpose layer.

The need for high performance semiconductor chips has continued to increase over the past several years. As demand for better performance and faster semiconductor chips has grown, so have efforts to reduce semiconductor chip size. Reducing the size of individual integrated circuit components can dramatically increase the speed and performance of a semiconductor chip. For example, smaller gate lengths in MOS transistors dramatically increase their switching speed.
The performance of semiconductor chips is limited by the electrical conductivity of the metal interconnects that electrically connect the various components that form the integrated circuits on the semiconductor chip. Therefore, in order to take full advantage of transistors that are capable of operating at faster speeds, the electrical interconnects must be highly conductive, yet low in resistance. Aluminum or an aluminum alloy was widely used as the preferred material for forming conductive interconnects by a process known as "metallization". "Metallization" is a term used in the semiconductor industry to describe the process of wiring together the components of an integrated circuit, and typically occurs by the process of electrochemical deposition. Aluminum emerged as the preferred metal for metallization because it has a relatively low resistivity, good current-carrying density, and superior adhesion to silicon dioxide. In addition, aluminum is available in high purity and has a natural low contact resistance with silicon.
However, aluminum and aluminum alloys present some disadvantages when used to make interconnects. For example, although aluminum has a resistance that can be tolerated by most integrated circuits, it is difficult to deposit in a high aspect ratio. In addition, aluminum and aluminum alloys suffer from eutectic formations, thermally induced voiding, and electromigration when used in very large scale integration (VLSI) and ultra large scale integration (ULSI) semiconductor chips.
Recently, copper metal has begun to replace aluminum and aluminum-silicon alloys in VLSI and ULSI metallization processes. Copper has better conductivity and is more reliable than aluminum or aluminum alloys. The use of copper for making semiconductor chip interconnects is appealing because of the low cost, high throughput, excellent via-filling capabilities, and high quality of the deposited copper film. In contrast to aluminum, copper is capable of being deposited with high aspect ratios. Copper is also a much better conductor than aluminum, provides good step coverage, is more resistant to electromigration and can be electrochemically deposited at low temperatures.
Because copper will diffuse into silicon if applied directly to a silicon-containing substrate, such as a silicon wafer, it is necessary to first apply a barrier layer between the substrate from which the semiconductor chip is fabricated and the copper layer. Additionally, the material must have a relatively low resistivity so that electrochemical deposition of copper on the surface of the barrier layer will occur. Unless the resistivity of the barrier material is relatively low, it will not function as a suitable surface for subsequent electrochemical deposition of the conductive interconnect material. Tantalum, for example, has a resistivity that is two orders of magnitude higher than copper. Accordingly, tantalum is generally not suitable to serve as the cathode during the electrochemical deposition process.
To overcome this resistivity concern, a seed layer is typically formed on top of the barrier layer to provide the desired resistivity. For the electrochemical deposition of copper, the seed layer is often a layer of PVD copper. Unfortunately, formation of the seed layer overlying the barrier layer necessarily adds a discrete process step.
Accordingly, there continues to be a need in the industry for improved methods and devices for forming conductive layers, such as used in device interconnects, onto barrier layers.

Electrochemical reaction cell for a combined barrier layer and seed layer


An image pickup apparatus includes an image pickup element configured to perform photoelectric conversion on an optical image obtained through an image pickup optical system to generate an image signal, a focus detection unit configured to perform focus detection based on the image signal, a determination unit configured to determine an object in a screen, a calculation unit configured to calculate an in-focus position based on information of the object determined by the determination unit, and a control unit configured to perform the in-focus control based on the in-focus position calculated by the calculation unit.

Field of the Invention
The present invention relates to an image pickup apparatus configured to perform focusing based on an image signal from an image pickup element that performs photoelectric conversion on an object image.
Description of the Related Art
Conventionally, there has been disclosed an image pickup apparatus including any of various kinds of automatic focusing apparatuses utilizing optical properties. Japanese Patent Laid-open No. 2009-069740 discloses an image pickup apparatus with an improved focusing accuracy over an entire image pickup screen.
However, the image pickup apparatus disclosed in Japanese Patent Laid-open No. 2009-069740 calculates a correction amount of an in-focus position based on a detected value of a contrast peak position difference between a ranging area in a central portion and a ranging area in a peripheral portion and a previously stored value of the contrast peak position difference, thereby performing drive control of a focus lens. In other words, in the image pickup apparatus of Japanese Patent Laid-open No. 2009-069740, the correction amount of the in-focus position does not depend on a focal length or an object distance. Such a configuration can provide an image with its resolution balanced between at the central and peripheral portions of the screen. However, when a main object such as a person's face of which image a photographer wants to capture is not at screen positions such as the central and peripheral portions where resolution is balanced, good resolution cannot be obtained for the main object.

Image pickup apparatus, image pickup system, method of controlling image pickup apparatus, and non-transitory computer-readable storage medium


A light-colored thermoplastic molding composition comprising a polyurethane elastomer is disclosed. The polyurethane which is the reaction product of at least one polyol, at least one organic diisocyanate and at least one polyol chain extender contains one or more pentaerythritol diphosphites color stabilizers conforming to a specific formula exhibits improved color stability and improved processability. The process for preparation entails introducing the stabilizer before the reaction has been completed.

The present invention relates to thermoplastically processable polyurethane elastomers (TPUs) having an improved intrinsic color as a result of the utilization of one or more compounds of pentaerythritol diphosphites substituted in specific manner, and to the use thereof.
Thermoplastic polyurethanes (TPUs) are widely used because they have good elastomer properties and lend themselves readily to thermoplastic further processing. A very varied range of mechanical properties may be obtained by suitable selection of components. Kunststoffe 68 (1978) 819; Kautschuk, Gummi, Kunststoffe 35, (1982) 569; G. Becker, D. Braun: Kunststoff-Handbuch [Manual of Plastics], Vol. 7, xe2x80x9cPolyurethane [Polyurethanes]xe2x80x9d, Munich, Vienna, Carl Hanser Verlag 1983, for example, contain an overview of TPUs and their properties and uses. An overview of processes for preparing them is given in Plastikverarbeiter [Plastic Processor] 40 (1989).
TPUs are constructed from generally linear polyols such as polyester polyols or polyether polyols, organic diisocyanates and short-chain, generally bifunctional, alcohols (chain extenders). They can be prepared in batch or continuous manner.
Thermoplastic polyurethanes are susceptible to discoloration because of the raw materials on which they are based and because of the thermal treatment to which they are twice exposed during their production and processing. Yet in many TPU applications the color of the article is an important property. Discoloration caused by heat during preparation of the TPUs or during processing by injection molding or extrusion is undesirable, in particular in the case of white or light-colored articles.
In U.S. Pat. No. 4 169 196 Ehrlich et al. describe a process for the preparation of TPUs based on 4,4xe2x80x2-diphenylmethane diisocyanate with a phosphorus component PX3 being utilized, in which X are aryl, aryloxy and low alkoxy groups, and with a reduced quantity of tin catalysts being utilized. A triphenyl phosphite is preferably utilized. Thermally stable, color-stable TPUs are obtained thus.
The GE Specialty Chemicals monograph (1997 by General Electrical Company) also describes specific phosphites for improving the stability in processing and the color stability of thermoplastics prepared from polyolefins, polyesters, polyvinyl chloride, polycarbonate, polystyrene, ABS, polyurethanes and other elastomers. Triphenyl phosphite, a range of tri(alkylphenyl)phosphites, a hydroxyalkyl triphosphite, two substituted pentaerythritol diphosphites
where R=stearyl and R=di(tert.-butyl)phenyl, and a substituted pentaerythritol monophosphite (R=tri(tert.-butyl)phenyl), are described.
The utilization of these phosphites reduces discoloration in thermoplastic polyurethanes during their preparation and processing.
However, the utiliation of phosphites in the preparation of TPUs also influences the reactivity (monomer reactivity) of the starting components (EP-A 0 522 340). The utilization of phosphites as color stabilizers in the preparation of TPUs is therefore problematic.
The object was to provide thermoplastically processable polyurethane elastomers which have a good intrinsic color which remains unchanged or is barely changed during preparation and/or processing.
It has now been found that TPUs having a good color (low Yellowness Index in accordance with DIN 6167) with unchanged monomer reactivity can be provided when pentaerythritol diphosphites substituted in specific manner are added to the reaction components before or during preparation of the TPUs.
The invention therefore provides light-colored thermoplastically processable polyurethane elastomers (TPUs) consisting of a reaction product which is obtainable from
A) at least one polyol having on average a minimum of 1.8 and a maximum of 3.0 Zerewitinoff-active hydrogen atoms and an average molecular weight Mn of 450 to 10000,
B) at least one organic diisocyanate and
C) at least one polyol having on average a minimum of 1.8 and a maximum of 3.0 Zerewitinoff-active hydrogen atoms and an average molecular weight Mn of 60 to 400,
wherein the NCO/OH ratio of the reaction components A), B) and C) which are used is between 0.85 and 1.2,
and from 0 to 20 wt. %, in relation to the quantity of TPU, of further auxiliary substances and additives (D),
as well as from 0.001 to 1 wt. %, in relation to the quantity of TPU, of one or more color stabilizers from the group comprising pentaerythritol diphosphites (E) corresponding to the formula (I)
wherein
R=C6 to C30-alkyl, in particular C6 to C20-alkyl, and Ph denotes phenyl.
The TPUs according to the invention preferably have a Yellowness Index (measured in accordance with DIN 6167) of less than 9, in particular of less than 8.
Aliphatic, cycloaliphatic, araliphatic, aromatic and heterocyclic diisocyanates or any mixtures of these diisocyanates may be used as organic diisocyanates (B) (cf. HOUBEN-WEYL xe2x80x9cMethoden der organischen Chemiexe2x80x9d [Organic Chemistry Methods], Vol. E20 xe2x80x9cMakromolekulare Stoffe [Macromolecular Substances]xe2x80x9d, Georg Thieme Verlag, Stuttgart, New York 1987, pp. 1587-1593 or Justus Liebig""s Annalen der Chemie [Annals of Chemistry], 562, pp. 75 to 136).
The following might be named in detail as examples: aliphatic diisocyanates such as ethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,1 2-dodecane diisocyanate; cycloaliphatic diisocyanates such as isophorone diisocyanate, 1,4-cyclohexane diisocyanate, 1-methyl-2,4-cyclohexane diisocyanate and l-methyl-2,6-cyclohexane diisocyanate as well as the corresponding isomer mixtures, 4,4xe2x80x2-dicyclohexylmethane diisocyanate, 2,4xe2x80x2-dicyclohexylmethane diisocyanate and 2,2xe2x80x2-dicyclohexylmethane diisocyanate as well as the corresponding isomer mixtures; furthermore aromatic diisocyanates such as 2,4-tolylene diisocyanate, mixtures of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate, 4,4xe2x80x2-diphenylmethane diisocyanate, 2,4xe2x80x2-diphenylmethane diisocyanate and 2,2xe2x80x2-diphenylmethane diisocyanate, mixtures of 2,4xe2x80x2-diphenylmethane diisocyanate and 4,4xe2x80x2-diphenylmethane diisocyanate, urethane-modified liquid 4,4xe2x80x2-diphenylmethane diisocyanates or 2,4xe2x80x2-diphenylmethane diisocyanates, 4,4xe2x80x2-diisocyanate- 1,2-diphenylethane and 1,5-naphthylene diisocyanate. 1,6-Hexamethylene diisocyanate, 1,4-cyclohexane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, diphenylmethane diisocyanate isomer mixtures having a 4,4xe2x80x2-diphenylmethane diisocyanate content of more than 96 wt. % and in particular 4,4xe2x80x2-diphenylmethane diisocyanate and 1,5-naphthylene diisocyanate, are used for preference. The named diisocyanates may be used individually or in the form of intermixtures. They may also be used together with up to 15 mol % (in relation to total diisocyanate) of a polyisocyanate, however polyisocyanate may be added only in a quantity such that a product which is still thermoplastically processable arises. Examples of polyisocyanates are triphenylmethane-4,4xe2x80x2,4xe2x80x3-triisocyanate and poly-phenyl-polymethylene polyisocyanates.
Zerewitinoff-active polyols (A) utilized in the products according to the invention are those such as have on average a minimum of 1.8 and a maximum of 3.0 Zerewitinoff-active hydrogen atoms and an average molecular weight {overscore (M)}n of 450 to 10000.
Besides compounds having amino groups, thiol groups or carboxyl groups, compounds having in particular two to three, preferably two, hydroxyl groups, are included, specifically those such as have average molecular weights {overscore (M)}n of 450 to 6000, particularly preferably those such as have an average molecular weight {overscore (M)}n of 600 to 4500, for example polyesters, polyethers, polycarbonates and polyester amides having hydroxyl groups.
Suitable polyether diols may be prepared by reacting one or more alkylene oxides having 2 to 4 carbon atoms in the alkylene radical with a starter molecule which comprises two bonded active hydrogen atoms. The following might be named as alkylene oxides, for example: ethylene oxide, 1,2-propylene oxide, epichlorohydrin and 1,2-butylene oxide and 2,3-butylene oxide. Ethylene oxide, propylene oxide and mixtures of 1,2-propylene oxide and ethylene oxide are used for preference. The alkylene oxides may be used individually, in an alternating sequence or as mixtures. The following are considered as the starter molecules, for example: water, amino alcohols such as N-alkyldiethanolamines, for example N-methyldiethanolamine, and diols such as ethylene glycol, 1,3-propylene glycol, 1,4-butanediol and 1,6-hexanediol. Mixtures of starter molecules may optionally also be utilized. Suitable polyetherols are moreover the polymerization products of tetrahydrofuran which comprise hydroxyl groups. Trifunctional polyethers may also be utilized in proportions of from 0 to 30 wt. %, in relation to the bifunctional polyethers, however only in a quantity such that a product which is still thermoplastically processable arises. For preference the substantially linear polyether diols have average molecular weights {overscore (M)}n of 450 to 6000. They may be used both individually and in the form of intermixtures.
Suitable polyester diols may, for example, be prepared from dicarboxylic acids having 2 to 12 carbon atoms, for preference 4 to 6 carbon atoms, and polyhydric alcohols. Examples of dicarboxylic acids which are considered are: aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid and sebacic acid, or aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid. The dicarboxylic acids may be used individually or as mixtures, for example in the form of a succinic, glutaric and adipic acid mixture. It may optionally be advantageous for preparing the polyester diols to use in place of the dicarboxylic acids the corresponding dicarboxylic acid derivatives such as carboxylic acid diesters having 1 to 4 carbon atoms in the alcohol radical, carboxylic acid anhydrides or carboxylic acid chlorides. Examples of polyhydric alcohols are glycols having 2 to 10, for preference 2 to 6 carbon atoms, for example ethylene glycol, diethylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,10-decanediol, 2,2-dimethyl-1,3-propanediol, 1,3-propanediol or dipropylene glycol. Depending on the desired properties, the polyhydric alcohols may be used alone or in intermixture. Esters of carbonic acid with the named diols, in particular those such as have 4 to 6 carbon atoms, such as 1,4-butanediol or 1,6-hexanediol, condensation products of xcfx89-hydroxycarboxylic acids such as xcfx89-hydroxyhexanoic acid or polymerisation products of lactones, for example optionally substituted xcfx89-caprolactones, are moreover suitable. Ethanediol polyadipates, 1,4-butanediol polyadipates, ethanediol-1,4-butanediol polyadipates, 1,6-hexanediol neopentyl glycol polyadipates, 1,6-hexanediol- 1,4-butanediol polyadipates and polycaprolactones are used for preference as the polyester diols. The polyester diols have average molecular weights {overscore (M)}n of 450 to 6000 and may be used individually or in the form of intermixtures.
Zerewitinoff-active polyols (C) are so-called chain extenders and have on average 1.8 to 3.0 Zerewitinoff-active hydrogen atoms and a molecular weight of 60 to 400. These are understood to be compounds having two to three, preferably two hydroxyl groups, besides those having amino groups, thiol groups or carboxyl groups.
For preference aliphatic diols having 2 to 14 carbon atoms, such as, for example, ethanediol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol and dipropylene glycol are utilised as the chain extenders. However, diesters of terephthalic acid with glycols having 2 to 4 carbon atoms, for example terephthalic acid bisethylene glycol or terephthalic acid bis1,4-butanediol, hydroxyalkylene ethers of hydroquinone, for example 1,4-di(xcex2-hydroxyethyl) hydroquinone, ethoxylated bisphenols, for example 1,4-di(xcex2-hydroxyethyl) bisphenol A, (cyclo)aliphatic diamines such as isophorone diamine, ethylene diamine, 1,2-propylene diamine, 1,3-propylene diamine, N-methylpropylene-1,3-diamine, N,Nxe2x80x2-dimethylethylene diamine and aromatic diamines such as 2,4-tolylene diamine, 2,6-tolylene diamine, 3,5-diethyl-2,4-tolylene diamine or 3,5-diethyl-2,6-tolylene diamine or primary mono-, di-, tri- or tetraalkyl-substituted 4,4xe2x80x2-diaminodiphenyl methanes are also suitable. Ethanediol, 1,4-butanediol, 1,6-hexanediol, 1,4-di(xcex2-hydroxyethyl) hydroquinone or 1,4-di(xcex2-hydroxyethyl) bisphenol A are particularly preferably used as the chain extenders. Mixtures of the aforementioned chain extenders may also be utilized. Smaller quantities of triols may additionally be added.
Compounds which are monofunctional with regard to isocyanates may be utilized in proportions of up to 2 wt. %, in relation to TPU, as the so-called chain terminators. Monoamines such as butylamine and dibutylamine, octylamine, stearylamine, N-methylstearylamine, pyrrolidine, piperidine or cyclohexylamine, monoalcohols such as butanol, 2-ethylhexanol, octanol, dodecanol, stearyl alcohol, the various amyl alcohols, cyclohexanol and ethylene glycol monomethyl ether, for example, are suitable.
The relative quantities of the compounds (A) and (C) are preferably selected such that the ratio of the sum of the isocyanate groups in (B) to the sum of the Zerewitinoff-active hydrogen atoms in (A) and (C) is from 0.85:1 to 1.2:1, preferably 0.95:1 to 1.1:1.
The thermoplastic polyurethane elastomers according to the invention may comprise as auxiliary substances and additives (D) up to a maximum of 20 wt. %, in relation to the quantity of TPU, of the conventional auxiliary substances and additives. Typical auxiliary substances and additives are catalysts, pigments, dyes, flame retardants, anti-ageing and weathering stabilizers, plasticizers, lubricants and mould release agents and fungistats and bacteriostats, as well as fillers and mixtures thereof.
Suitable catalysts according to the invention are the conventional tertiary amines known from the prior art, such as, for example, triethylamine, dimethyl cyclohexylamine, N-methyl morpholine, N,Nxe2x80x2-dimethyl piperazine, 2-(dimethylaminoethoxy) ethanol, diazabicyclo[2,2,2]octane and the like, as well as in particular organic metal compounds such as titanic acid esters, iron compounds or tin compounds such as tin diacetate, tin dioctoate, tin dilaurate or the tin dialkyl salts of aliphatic carboxylic acids, such as dibutyltin diacetate or dibutyltin dilaurate or the like. The preferred catalysts are organic metal compounds, in particular titanic acid esters, iron compounds and tin compounds. The total catalyst quantity in the TPUs according to the invention is generally from about 0 to 5 wt. %, preferably 0 to 2 wt. %, in relation to the quantity of TPU.
Examples of further additives are lubricants such as fatty acid esters, metal soaps thereof, fatty acid amides, fatty acid ester amides and silicone compounds, anti-blocking agents, inhibitors, hydrolysis stabilizers and light, heat and discoloration stabilizers, flame retardants, dyes, pigments, inorganic and/or organic fillers and reinforcing agents. The reinforcing agents are in particular fibrous reinforcing materials such as, for example, inorganic fibers prepared in accordance with the prior art, which may also be provided with a size. More detailed information regarding the named auxiliary substances and additives may be found in the specialist literature, for example the monograph by J. H. Saunders and K. C. Frisch, xe2x80x9cHigh Polymersxe2x80x9d, Vol. XVI, Polyurethane, Parts 1 and 2, Interscience Publishers 1962 and 1964, respectively, the Taschenbuch fxc3xcr Kunststoff-Additive [Manual of Plastics Additives] by R. Gxc3xa4chter and H. Mxc3xcller (Hanser Verlag Munich 1990) or DE-A 29 01 774.
Further additions which may be incorporated in the TPU are thermoplastics, for example polycarbonates and acrylonitrile/butadiene/styrene terpolymers, in particular ABS. Other elastomers such as rubber, ethylene/vinyl acetate copolymers and styrene/butadiene copolymers as well as other TPUs may also be used.
Conventional commercial plasticizers such as phosphates, phthalates, adipates, sebacates and alkylsulfonic acid esters are further suitable for incorporation.
The color stabilizers (E) which are utilized are substituted pentaerythritol diphosphites
in which R=C6 to C30-alkyl, preferably C6 to C20-alkyl, and Ph denotes phenyl.
The following should be named as examples: bis(hexylphenyl) pentaerythritol diphosphite, bis(octylphenyl) pentaerythritol diphosphite, bis(nonylphenyl) pentaerythritol diphosphite, bis(decylphenyl) pentaerythritol diphosphite, bis(stearylphenyl) pentaerythritol diphosphite, bis(2,4-hexylphenyl) pentaerythritol diphosphite and bis(2,4-nonylphenyl) pentaerythritol diphosphite.
The named compounds may be used individually, as isomer mixtures or in the form of intermixtures.
They are utilized at concentrations of from 0.001 to 1 wt. %, in relation to the quantity of TPU, preferably 0.01 to 0.5 wt. %.
For preference the color stabilizers are added to the reaction components, preferably to the polyol, before the reaction. They may, however, also be dispensed directly into the extruder, for example in the case of continuous preparation of TPUs in an extruder.
The invention also provides a process for the preparation of the thermnoplastically processable polyurethane elastomers according to the invention, which is characterized in that the components A), B) and C) are reacted, the components D) are added before, during or after the reaction in a quantity of from 0 to 20 wt. %, in relation to the quantity of TPU, and the components E) are added before or during the reaction in a quantity of from 0.001 to 1 wt. %, in relation to the quantity of TPU, wherein the NCO/OH ratio of the components A), B) and C) which are utilized is between 0.85 and 1.2, and in that the product thus obtained is then molded.
The TPUs may be prepared in batch or continuous manner. In the continuous preparation, the TPUs according to the invention may be prepared, for example, by the mixing head/band-type process or the so-called extruder process. In the extruder process, for example in a multi-screw extruder, the components A), B) and C) may be dispensed in simultaneous manner, that is to say, by the one-shot process, or sequentially, that is to say by a prepolymer process. Here, the prepolymer may take the form of an initial batch, and it may also be prepared in continuous manner in a part of the extruder or in a separate prepolymer unit upstream.
The TPU according to the invention may optionally be further worked, for example by annealing of the polymer in the form of sheets or blocks, comminution or granulation in shredders or mills, and de-gassing, as well as granulation with melting. The polymer is preferably guided through a unit for continuous de-gassing and strand formation. This unit may be constituted, for example, by a multi-screw machine equipped if possible with no or few kneading elements.
The TPUs according to the invention are utilized for the production of injection molded articles and extruded articles.
The TPUs to which the color stabilizers have been added have good mechanical and elastic properties. Surprisingly, they have in addition very low to zero optically visible coloration, in comparison with known TPUs to which phosphites have been added, while at the same time retaining the monomer reactivity. The Yellowness Index of the TPUs according to the invention, measured in accordance with DIN 6167, is less than 9.
The Yellowness Index is also still less than 9 after the further processing steps of injection molding or extrusion, such as are conventional for a TPU.

Thermoplastically processable polyurethane elastomers having an improved intrinsic color