A sheet pick-up device includes a sheet pick-up arm, a driving shaft and a collar. The sheet pick-up arm has a sleeve at the outside surface thereof. The driving shaft is penetrated through the sheet pick-up arm and the sleeve. The collar is sheathed around the driving shaft and includes at least one flexible vane in contact with the inner surface of the sleeve. The height of the flexible vane relative to the outer surface of the collar is greater than the radial distance between the outer surface of the collar and the inner surface of the sleeve.

Image capturing apparatuses such as image scanners, facsimile machines, printers or copiers are widely used for capturing or scanning images of documents. As known, the image capturing apparatus usually has a document feeder for successively and continuously feeding many paper sheets. Typically, the document feeder has a sheet pick-up device in contact with the front edges of the documents so as to feed the paper sheets one by one.
Referring to FIGS. 1A and 1B, schematic cross-sectional views of a sheet pick-up device of a document feeder are respectively illustrated. FIG. 1A schematically illustrates the sheet pick-up device in a feeding mode. FIG. 1B schematically illustrates the sheet pick-up device in a standby mode. The sheet pick-up device 2 is disposed under an upper cover 3. The operation principles of the sheet pick-up device in the feeding mode and the standby mode are illustrated as follows.
As shown in FIG. 1A, when the document feeder 1 is operated in the feeding mode, a driving shaft 21 of the sheet pick-up device 2 is driven by a motor (not shown) to rotate in a direction R1, and a sheet pick-up arm 22 of the sheet pick-up device 2 is lowered to a sheet feeding position. Meanwhile, a sheet pick-up roller 221 of the sheet pick-up arm 22 transports a document S forwardly and a sheet separation roller 222 of the sheet pick-up arm 22 is rotated to separate the top paper sheet from the stack of paper sheets, thereby picking a single paper sheet.
As shown in FIG. 1B, after the document S has been fed across the sheet separation roller 222, the driving shaft 21 is driven by the motor to rotate in a direction R2, the sheet pick-up arm 22 of the sheet pick-up device 2 is lifted to a standby position.
In the above document feeder 1, the sheet pick-up arm 22 is transmitted by the driving shaft 21 to move in either the sheet feeding position or the standby position with the assistance of two one-way spring clutches. Referring to FIG. 1C, a schematic perspective view of the sheet pick-up device 2 is illustrated. The sheet pick-up device 2 of FIG. 1C includes two one-way spring clutches 23A and 23B, which are mounted on the driving shaft 21 and connected to the sheet pick-up arm 22. The operation principles of these two one-way spring clutches 23A and 23B will be illustrated as follows.
First of all, please refer to FIGS. 1A, 1B and 1C. When a sheet feeding operation of the document feeder 1 is initiated, the driving shaft 21 is rotated in the direction R1 by the spring clutch 23A so as to descend the sheet pick-up arm 22 to the sheet feeding position. When the sheet feeding operation is terminated, the driving shaft 21 is rotated in the direction R2 and the loading generated from the sheet pick-up arm 22 is balanced off by the spring clutch 23A. Meanwhile, the sheet pick-up arm 22 is lifted to the standby position.
Please refer to FIGS. 1A, 1B and 1C again. When the sheet pick-up arm 22 is further lifted to touch the upper cover 3, the spring clutch 23B is operated to allow for idle running of the driving shaft 21 in the direction R2, thereby reducing the possibility of uplifting the upper cover 3 by the sheet pick-up arm 22.
A sheet pick-up device which has two one-way spring clutches was disclosed in for example U.S. Pat. No. 6,390,463, the contents of which are hereby incorporated by reference.
Although the approach of mounting two one-way spring clutches 23A and 23B on the driving shaft is advantageous for reducing the possibility of uplifting the upper cover by the sheet pick-up arm, there are still some drawbacks. For example, the extra one-way spring clutch increases the cost of the document feeder 1 as well as the complexity of the sheet pick-up device 2.
In views of the above-described disadvantages resulted from the prior art, the applicant keeps on carving unflaggingly to develop an improved sheet pick-up device according to the present invention through wholehearted experience and research.


A method for chemical mechanical polishing of mirror structures. The method includes providing a semiconductor substrate, e.g., silicon wafer. The method includes forming a first dielectric layer overlying the semiconductor substrate and forming an aluminum layer overlying the first dielectric layer, the aluminum layer having an upper surface with a predetermined roughness of greater than 20 Angstroms RMS. The method also includes processing regions overlying the upper surface of the aluminum layer using a touch polishing process to reduce a surface roughness of the upper surface of aluminum layer to less than 5 Angstroms to form a mirror surface on the aluminum layer. Preferably, a protective layer is formed overlying the mirror surface on the aluminum layer. The method includes patterning the aluminum layer to expose portions of the dielectric layer to form a plurality of pixel regions defined by borders from the exposed portions and forming a second dielectric layer overlying the patterned aluminum layer and exposed portions of the first dielectric layer. The method includes removing a portion of the second dielectric layer to expose the protective layer, whereupon the protective layer acts as a polish stop layer. In a specific embodiment, the selectivity between the protective layer and the second dielectric layer is 1:30 or greater.

The present invention is directed to integrated circuits and their processing for the manufacture of electronic devices. More particularly, the invention provides a method for manufacturing an electrode structure for a liquid crystal on silicon ("LCOS") device for displays. But it would be recognized that the invention has a much broader range of applicability.
Electronic display technologies have rapidly developed over the years. From the early days, cathode ray tube technology, commonly called CRTs, outputted selected pixel elements onto a glass screen in conventional television sets. These television sets originally output black and white moving pictures. Color television sets soon replaced most if not all black and white television units. Although very successful, CRTs were often bulky, difficult to make larger, and had other limitations.
CRTs were soon replaced, at least in part, with liquid crystal panel displays. These liquid crystal panel displays commonly called LCDs used an array of transistor elements coupled to a liquid crystal material and color filter to output moving pictures in color. Many computer terminals and smaller display devices often relied upon LCDs to output video, text, and other visual features. Unfortunately, liquid crystal panels often had low yields and were difficult to scale up to larger sizes. These LCDs were often unsuitable for larger displays often required for television sets and the like.
Accordingly, projection display units have been developed. These projection display units include, among others, a counterpart liquid crystal display, which outputs light from selected pixel elements through a lens to a larger display to create moving pictures, text, and other visual images. Another technology is called "Digital Light Processing" (DLP), which is a commercial name from Texas Instruments Incorporated (TI) of Texas, USA. DLP is often referred to as the use of "micro-mirrors." DLP relies upon a few hundred thousand tiny mirrors, which line up in 800 rows of 600 mirrors each. Each of the mirrors is hinged. An actuator is attached to each of the hinges. The actuator often has electrostatic energy that can tilt each of the mirrors at high frequency. The moving mirrors can modulate light, which can be transmitted through a lens and then displayed on a screen. Although DLP has been successful, it is often difficult to manufacture and subject to low yields, etc.
Yet another technique is called LCOS. LCOS uses liquid crystals applied to a reflective mirror substrate. As the liquid crystals "open" or "close," light is reflected or blocked, which modulates the light to create an image for display. Compared to the conventional transmissive LCD, a reflective LCOS display allows more light to be passed through the optics and therefore it provides a higher luminance. Often times, there are at least three LCOS chips in a projection system, each corresponding to light in red, green, and blue channels. LCOS, however, has many limitations. As merely an example, LCOS is often difficult to manufacture. Additionally, LCOS requires at least the three chips that make the projector bulky and heavy and leads to high costs.
Conventional LCOS also uses aluminum material as a reflective film for electrodes. Conventional LCOS has relatively low reflectivity, and rough surface. Al mirrors are typically patterned using etch. A conventional method to smooth the aluminum/oxide is chemical mechanical planarization, commonly called the Al CMP processes. CMP process, however, causes many undesirable issues, such as dishing, micro-scratching, and oxidation of the aluminum surfaces. These and other limitations are described in greater detail below.
From the above, it is seen that an improved technique for processing devices is desired.

Method and structure for aluminum chemical mechanical polishing and protective layer

Semiconductor Manufacturing International (Shanghai) Corporation


A network configuration file is generated at a host computer and downloaded to a digital camera. This file contains instruction information for communicating with a selected destination via a communications interface. The digital camera includes a “send” button or LCD icon which allows the user to easily transmit one or more images via a wired or wireless communications interface to a desired destination, which among other possibilities may be an Internet Service Provider or a digital photofinishing center. When the user selects this option, the communications port settings, user account specifics, and destination connection commands are read from the network configuration file on the removable memory card. Examples of these settings include serial port baud rate, parity, and stop bits, as well as account name and password.

Digital cameras, such as the Kodak Digital Science DC25™ camera, allow images to be utilized on a home computer (PC) and to be incorporated into e-mail documents and personal home pages on the World Wide Web. Presently, images must be copied to the PC and transmitted as e-mail, for example using an online service or an Internet Service Provider (ISP), via a modem from the user's PC. It would be desirable to be able to transmit pictures directly from the digital camera instead of first transferring the pictures to a PC. For instance, on a vacation trip, it is desirable to immediately share pictures with friends or relatives via e-mail or Internet access. It is also desirable to transmit pictures from a location without PC access in order to free up camera storage to take additional pictures. There are a wide variety of connection means to online services such as America On Line, ISPs, and bulletin board services. Each of these services typically requires an account name and password, as well as local telephone access numbers, and specific communications settings. It would be difficult to provide an easy-to-use means with buttons or menus on a small digital camera to input and/or modify all of these required settings.

This patent is subject to a terminal disclaimer.

Automatically transmitting images from an electronic camera to a service provider using a network configuration file


A separable loadbreak connector system includes mating electrical connectors. At least one of the electrical connectors includes an electrically-resistive housing having a generally conically-shaped interior bore. A semiconductive insert is disposed within a portion of the interior bore and presents an inner radial surface that defines a generally conically-shaped recess. An elongated probe assembly is disposed within the housing and includes a probe and a sheath of insulative material disposed over at least a portion of a length of the probe. A portion of the sheath extends in a radially outward direction from a base of the probe. An electrically-resistive insulative layer extends from the conically-shaped interior bore, along at least a portion of the inner radial surface of the semiconductive insert. The insulative layer extends radially inwardly in overlapping engagement with a portion of the sheath.

This invention relates generally to bus systems and cable connectors for electric power systems, and more particularly to separable insulated loadbreak connector systems for use with modular bus systems.
Electrical power is typically transmitted from substations through cables which interconnect other cables and electrical apparatus in a power distribution network. The cables are typically terminated on bushings that may pass through walls of metal encased equipment such as capacitors, transformers or switchgear.
Separable loadbreak connectors allow connection or disconnection of the cables to the electrical apparatus for service, repair, or expansion of an electrical distribution system. Such connectors typically include a contact tube surrounded by elastomeric insulation and a semiconductive ground shield. Insulated connector probe sleeves are cylindrical with a very small bonding area at the bottom portion of the interface cylinder. A contact piston is located in the contact tube, and a female contact having contact fingers is coupled to the piston. An arc interrupter, gas trap and arc-shield are also mounted to the contact tube. The female contact fingers are matably engaged with an energized male contact of a mating bushing, typically an elbow connector, to connect or disconnect the power cables from the apparatus. The piston is movable within the contact tube to hasten the closure of the male and female contacts and thus extinguish any arc created as they are engaged.
The connectors are coupled to various sized and shaped pieces of bus work to complete the interconnection. Typically the bus work comprises bus bars sized at the site of assembly to account for various configurations of cable risers that carry cables to the electrical switchgear. Such variety of component pieces makes repair or replacement of the components laborious in that each piece is generally custom made and assembled. Insulation is provided between the bus bars and the active switching elements to prevent electrical arcing. There are three common types of insulation typically used in conventional switchgear: oil, sulfur hexafluoride (SF6) gas, and air. Each type of insulation insulates each part of the switchgear from the other parts of the switchgear (bus bar and active switching elements), and from the outer surfaces of the container of the switchgear. However, SF6 gas is difficult to contain, air requirements excessive spacing between energized parts to be an effective insulator, and oil is also difficult to contain and is a fire hazard.
To increase a flashover distance between energized portions and grounded portions of the connector some known connectors are insulated using layers of insulative material covering a length of the energized portion and/or a semi-conductive portion. For example, an insulative layer may be disposed within the recess of the connector along an inner surface. A probe assembly may be contained within the connector and aligned down the axis of the recess. An insulative sheath covers a portion of the exterior of the probe. The insulative sheath surrounding the probe and the insulative layer covering the inner surface of the housing are formed separately and insulative layer is expected to bond securely to insulative sheath at an abutting joint. However, if the abutting joint is not abutted and securely bonded, a gap between the insulative sheath and the insulative layer permits shorting the flashover distance between the energized contact extension and ground potential at an opening end of interface.

Separable electrical connector with reduced risk of flashover


A data driver circuit which enables the square measure of the non-display areas of image display devices to be reduced is to be provided. The driver circuit has two DA converters which convert the digital signals, in accordance with more significant bits thereof, into analog voltages; a voltage divider which divides the output voltages of the two DA converters in accordance with less significant bits of the signals; and a shift register which generates trigger signals in synchronism with the digital signals. The voltage divider, arranged in the gap between the two DA converters, comprises memory elements arrayed in two-dimensional matrixes, and a plurality of resistive wirings. The memory elements store decoded signals generated by the decoders in synchronism with the trigger signals, and selectively supply, in accordance with the decoded signals stored by the memory elements, the divided voltages which derive from the two DA converters and are generated on the resistive wirings.

In an active matrix type display, typically an active matrix type liquid crystal display, a thin film transistor (TFT) is formed in each pixel, and display information is stored on a pixel-by-pixel basis to display images. A TFT formed by using a polysilicon film which is fabricated by polycrystallization of an amorphous silicon film by laser annealing, with its mobility being raised to about 100 cm2/V·S is called a polysilicon TFT. Since a circuit configured of such polysilicon TFTs operates with signals of a few MHz to dozens of MHz, not only pixels but also a data driver circuit generating image signals and a driver circuit which has the scanning function of a gate driver circuit can be formed on the substrate of a liquid crystal display device or the like in the same process as the formation of the TFTs constituting the pixels.
The data driver circuit supplies an analog-signal voltage containing image signal information to a plurality of data lines. The data lines in this context are wires running in the vertical direction within the display screen of the image display device, and supply each pixel with an analog signal voltage.
The data driver circuit requires the following functions.
(1) A function to convert digital signals into analog voltages, namely the function of a DA converter. Where input image signals supplied from outside the image display device include many digital signals, it is preferable to build this function into the device.
(2) A function to distribute analog signal voltages. This is required because there are a plurality of data lines (usually as many as pixels in the horizontal direction of the frame).
FIG. 11 shows an example of configuration of a conventional data driver circuit. The data driver circuit comprises a decoder (DEC) 81, a shift register (SREG) 82 and a switch matrix 83. In the switch matrix 83, memory elements 84 each consisting of N-channel TFTs 85 and 86 and one capacitor 87 are arranged in a matrix form, and connected to one another by a plurality of decoded signal lines 88, a plurality of trigger lines 89, a plurality of reference voltage lines 90 and a plurality of output lines 91. The decoded signal lines 88 are connected to the output of the decoder 81, the trigger lines 89 to the shift register 82, the reference voltage lines 90 to external reference voltage lines Vref1 through Vrefx, and the output lines 91, to the data lines of the image display device.
The operation of the data driver circuit shown in FIG. 11 will be briefly described below. Digital image signals DSIG supplied from outside are decoded by the decoder 81, and supplied to the decoded signal lines 88. One of the decoded signal lines 88 relates to the entered digital image signal DSIG and takes on a sufficiently high voltage (hereinafter abbreviated to the H level) to turn ON the N-channel TFT, and the remaining ones take on a sufficiently low voltage (hereinafter abbreviated to the L level) to turn OFF the N-channel TFT. The shift register 82 successively raises one or another of the trigger lines 89 to the H level in synchronism with the input timings of the digital image signals DSIG.
On one column of the memory elements 84 connected to a trigger line 89 at the H level, as the TFT 85 is turned ON, the decoded signal on a decoded signal line 88 is latched into the capacitor 87. Out of the decoded signal lines 88, only one corresponding to the digital image signal DSIG is at the H level, and accordingly the capacitor 87 connected to that decode line samples the H level. Then, the TFT 86 to be connected to the capacitor 87 having sampled the H level is turned ON, and that TFT 86 selects one of the reference voltages Vref1 through Vrefx of the reference voltage lines 90 to be connected and outputs it to the output line 91. The reference voltage supplied to the output lines 91 is further fed to a data line of the image display device (not shown).
The operation described above causes the circuit of FIG. 11 (1) to convert digital image signals into corresponding voltage signals and (2) to distribute the voltage signals among the plurality of data lines, and is thereby enabled to perform its above-stated functions as a data driver circuit.
Examples of the circuit shown in FIG. 11 are also described in detail in Patent Document 1 and Patent Document 2. One of the features of the circuit shown in FIG. 11 is that, since the configuration requires merely the wiring of two lines per output in the longitudinal direction of the drawing, the circuit width per output can be narrowed, enabling the circuit to be applied to finer image display devices.
Patent Document 1: Japanese Patent Laid-Open No. 2003-005716
Patent Document 2: Japanese Patent Laid-Open No. 2004-085666

Image display device and the driver circuit thereof


A hydraulic system for a vehicle includes a first hydraulic circuit, a second hydraulic circuit, and a main actuator. The first hydraulic circuit includes a first pump having a flow outlet; a first pressure line having a pump end coupled to the flow outlet of the first pump; and a first load sensing line having a pump end coupled to the first pump and a pressure end coupled to the first pressure line. The second hydraulic circuit includes a second pump having a flow outlet; a second pressure line having a pump end coupled to the flow outlet of the second pump; and a second load sensing line having a pump end coupled to the second pump and a pressure end coupled to the second pressure line. The main actuator is coupled to the first pressure line and the second pressure line and is configured to oppose a load force. The first load sensing line is separate from the second load sensing line such that the first pump and the second pump respond independently to the load force.

The present invention relates generally to the field of vehicle hydraulic systems. The present invention relates more specifically to a load sensing system for vehicle hydraulic system including multiple hydraulic pumps and multiple actuators.
Hydraulic systems typically include a pressure source (e.g., a hydraulic pump), a hydraulic circuit through which the pressurized fluid is transported, and one or more devices (e.g., hydraulic cylinders, hydraulic motors, etc.) in which the pressure is used to do work. Flow of hydraulic fluid to the device may be controlled with a valve in the hydraulic circuit. The hydraulic pump may be a fixed displacement hydraulic pump that provides a fixed flow rate of hydraulic fluid. Because the hydraulic system may include several devices and more than one of the devices may be operated simultaneously using the pressurized hydraulic fluid, the pump is typically sized to provide a flow rate and pressure that is sufficient to run all or a number of the devices simultaneously. However, if only one device is operated with the hydraulic pump providing an excessive flow rate and pressure, excess pressure accumulates in the hydraulic circuit. To prevent damage to the components of the hydraulic system, a high pressure relief valve may be provided in the hydraulic circuit which allows excess hydraulic fluid to pass through the system (e.g., to a fluid reservoir). However, the hydraulic pump consumes excessive energy to provide a high fluid flow rate, the excess energy being converted to heat that can shorten the system life and jeopardize system function.
In current refuse industry vehicles, the hydraulic systems may include multiple hydraulic pumps working together to provide the pressure and flow rate required by several devices such as hydraulic actuators, with the flow to each of the devices controlled through valves in the hydraulic circuit. The hydraulic source used may be variable displacement hydraulic pumps with a pressure compensating load sensing system to regulate the output of the source and provide hydraulic fluid at a desired flow rate and pressure to match the varying demand of the multiple devices. The load sensing signals, the flow, or both are typically combined before the control valves.
When performing refuse collection functions, the working load faced by one valve from the associated actuator will likely affect both pumps. If a high load is sensed at one valve, the pressure in the system is increased to compensate and the other valves operate under unnecessarily high pressures, reducing the energy efficiency of the hydraulic system and potentially causing undesired, erratic movement of the actuators. In some cases, the unnecessarily high pressure can prevent normal performance of the system or contribute to the premature failure of components of the hydraulic system. When the load sense and flow are combined between pumps and the valves, one pump may become saturated before the other pump begins operating. One pump may work constantly while another pump only works intermittently. Flow limiters may be added to prevent one pump from operating excessively, but this adds cost and complexity to the hydraulic system. Further, the combined load sensing typically may amplify the load shocks and pressure spikes in the hydraulic system. This amplification can cause erratic or jerky movement of the actuators and accelerate premature failure of the components of the hydraulic system.

Independent load sensing for a vehicle hydraulic system


An electron device including a diamond material electron emitter and an anode, both disposed on a supporting substrate, so as to define an interelectrode region therebetween. Electron transport across the interelectrode region is initiated at an emitting surface of the diamond material electron emitter. An alternative embodiment employs a gate electrode disposed substantially symmetrically and axially displaced about the electron emitter and substantially in the interelectrode region to provide a modulation capability.

Electron devices employing ballistic transport of electrons are known in the art. However, known prior art devices suffer from a number of shortcomings. Prior art vacuum tube devices are large and not integrable. Recently developed field emission electron devices require very high electric fields and very small features on the order of a few hundreds of angstroms to achieve the very high electric fields. Planar field emission electron devices, known in the art, require sub-micron (less than 0.05 micron) electrode feature sizes to enable device operation.
Accordingly there exists a need for an electron device which overcomes at least some of the shortcomings of the prior art.

Electron device employing a diamond film electron source


Described are non-invasive methods of detecting the presence of specific nucleic acid sequences as well as nucleic acid modifications and alterations by analyzing urine samples for the presence of transrenal nucleic acids. More specifically, the present invention encompasses methods of detecting specific fetal nucleic acid sequences and fetal sequences that contained modified nucleotides by analyzing maternal urine for the presence of fetal nucleic acids. The invention further encompasses methods of detecting specific nucleic acid modifications for the diagnosis of diseases, such as cancer and pathogen infections, and detection of genetic predisposition to various diseases. The invention specifically encompasses methods of analyzing specific nucleic acid modifications for the monitoring of cancer treatment. The invention further encompasses methods of analyzing specific nucleic acids in urine to track the success of transplanted cells, tissues and organs. The invention also encompasses methods for evaluating the effects of environmental factors and aging on the genome.

(Not Applicable)
The present invention encompasses non-invasive methods of detecting the presence of specific nucleic acid sequences as well as nucleic acid modifications and alterations by analyzing urine samples for the presence of transrenal nucleic acids. More specifically, the present invention encompasses methods of detecting specific fetal nucleic acid sequences and fetal sequences that contained modified nucleotides by analyzing maternal urine for the presence of fetal nucleic acids. The invention further encompasses methods of detecting specific nucleic acid modifications for the diagnosis of diseases, such as cancer and pathogen infections, and detection of genetic predisposition to various diseases. The invention specifically encompasses methods of analyzing specific nucleic acid modifications for the monitoring of cancer treatment. The invention further encompasses methods of analyzing specific nucleic acids in urine to track the success of transplanted cells, tissues and organs. The invention also encompasses methods for evaluating the effects of environmental factors and aging on the genome.
Human genetic material is an invaluable source of information. Over the last several decades, scientific endeavors have developed many methods of analyzing and manipulating this genetic material (nucleic acids, DNA and RNA) for a variety of uses. These applications of molecular biology have been at the heart of numerous modern medical techniques for diagnosis and treatment. Thus, means of obtaining, isolating and analyzing this genetic material has become of foremost importance.
Until now, the fragile nature of nucleic acids, and their location encapsulated within cells, made the acquisition of genetic material for diagnosis in certain cases necessarily intrusive. For example, tumor diagnosis often requires surgery to obtain tumor cells. Similarly, doctors perform amniocenteses to obtain fetal DNA for a variety of diagnostic uses. This procedure requires the insertion of a needle through the abdomen of a pregnant woman and into the amniotic sac. Such intrusive practices carry with them a level of risk to both the fetus and the mother. While developments in ultrasound have contributed less intrusive alternative methods of fetal monitoring during pregnancy, these methods are not appropriate for diagnosing certain genetic defects and are not effective during the early stages of pregnancy, even for determining fetal sex.
Recent studies into the various mechanisms and consequences of cell death have opened a potential alternative to the invasive techniques described above. It is well established that apoptotic cell death is frequently accompanied by specific internucleosomal fragmentation of nuclear DNA. However, the fate of these chromatin degradation products in the organism has not been investigated in detail.
Based on the morphology of dying cells, it is believed that there exist two distinct types of cell death, necrosis and apoptosis. Kerr, J. F. et al., Br. J. Cancer 26:239-257, (1972). Cell death is an essential event in the development and function of multicellular organisms. In adult organisms, cell death plays a complementary role to mitosis in the regulation of cell populations. The pathogenesis of numerous diseases involves failure of tissue homeostasis which is presumed to be linked with cytotoxic injury or loss of normal control of cell death. Apoptosis can be observed during the earliest stages of embryogenesis in the formation of organs, substitution of one tissue by another and resorption of temporary organs.
Necrosis is commonly marked by an early increase in total cell volume and subcellular organelle volume followed by autolysis. Necrosis is considered to be a catastrophic metabolic failure resulting directly from severe molecular and/or structural damage. Apoptosis is an atraumatic programmed cell death that naturally occurs in the normal development and maintenance of healthy tissues and organs. Apoptosis is a much more prevalent biological phenomenon than necrosis. Kerr, J. F. et al., Br. J. Cancer 26:239-257, (1972). Umansky, S. Molecular Biology (Translated from Molekulyarnaya Biologiya) 30:285-295, (1996). Vaux, D. L. et al., Proc Natl Acad Sci USA. 93:2239-2244, (1996). Umansky, S., J. Theor. Biol. 97:591-602, (1982). Tomei, L. D. and Cope, F. D. Eds., Apoptosis: The Molecular Basis of Cell Death, Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y., (1991).
Apoptosis is also a critical biological function which occurs naturally during embryogenesis, positive and negative selection of T and B-lymphocytes, glucocorticoid induced lymphocyte death, death induced by radiation and temperature shifts, and death following deprivation of specific growth factors. In addition, apoptosis is an important part of an organism""s defense against viral infection. Apoptosis has been observed in preneoplastic foci found in the liver following tumor promoter phenobarbital withdrawal, in involuting hormone-dependent tissues and in tumors upon hormone withdrawal. Many antitumor drugs, including inhibitors of topoisomerase II as well as tumor necrosis factors induce apoptotic cell death. Apoptotic cell death is characterized by morphologic changes such as cellular shrinkage, chromatin condensation and margination, cytoplasmic blebbing, and increased membrane permeability. Gerschenson et al. (1992) FASEB J. 6:2450-2455; and Cohen and Duke (1992) Ann. Rev. Immunol. 10:267-293. Specific internucleosomal DNA fragmentation is a hallmark for many, but notably not all, instances of apoptosis.
In necrotic cells, DNA is also degraded but as a result of the activation of hydrolytic enzymes, generally yielding mono- and oligonucleotide DNA products. Afanasyev, V. N. et al., FEBS Letters. 194: 347-350 (1986).
Recently, earlier stages of nuclear DNA degradation have been described. It was shown that after pro-apoptotic treatments, DNA cleavage begins with the formation of high molecular weight DNA fragments in the range of 50-300 kilobases, the size of DNA found in chromosome loops. Walker, P. R. et al., Cancer Res. 51:1078-1085 (1991). Brown, D. G. et al., J. Biol. Chem. 268:3037-3039 (1993). These large fragments are normally degraded to nucleosomes and their oligomers. However, in some cases of apoptotic cell death only high molecular weight DNA fragments can be observed. Oberhammer, F. et al., EMBO J. 12:3679-3684 (1993). There are also data on the appearance of such fragments in some models of necrotic cell death. Kataoka, A. et al., FEBS Lett. 364:264-267 (1995).
Available data on the fate of these chromatin degradation products in organisms provide little guidance. Published results indicate that only small amounts of DNA can be detected in blood plasma or serum. Fournie, G. J. et al., Gerontology 39:215-221 (1993). Leon, S. et al., Cancer Research 37:646-650 (1977). It can be difficult to ensure that this DNA did not originate from white blood cells as a result of their lysis during sample treatment.
Extracellular DNA with microsatellite alterations specific for small cell lung cancer and head and neck cancer was found in human serum and plasma by two groups. Chen, X. Q. et al., Nature Medicine 2:1033-1035 (1996). Nawroz, H. et al., Nature Medicine 2:1035-1037 (1996). Others have proposed methods of detecting mutated oncogene sequences in soluble form in blood. U.S. Pat. No. 5,496,699, to George D. Sorenson. However, the use of blood or plasma as a source of DNA is both intrusive to the patient and problematic for the diagnostic technician. In particular, a high concentration of proteins (about 100 mg/ml) as well as the presence of compounds which inhibit the polymerase chain reaction (PCR) make DNA isolation and analysis difficult.
A few groups have identified, by PCR, DNA modifications or viral infections in bodily fluids, including urine. Ergazaki, M., et al., xe2x80x9cDetection of the cytomegalovirus by the polymerase chain reaction, DNA amplification in a kidney transplanted patient,xe2x80x9d In Vivo 7:531-4 (1993); Saito, S., xe2x80x9cDetection of H-ras gene point mutations in transitional cell carcinoma of human urinary bladder using polymerase chain reaction,xe2x80x9d Keio J Med 41:80-6 (1992). Mao, L., et al., xe2x80x9cMolecular Detection of Primary Bladder Cancer by Microsatellite Analysis,xe2x80x9d Science 271:659-662 (1996). The DNA that these groups describe detecting is from kidney cells or cells lining the bladder. When detecting a viral infection, many viruses infect cells of the bladder, thereby obtaining entry into the urine. The descriptions do not teach methods of detecting DNA sequences in urine that do not originate from the bladder or kidney cells, and thus would not include DNA that passes through the kidney barrier and remains in detectable form in urine prior to detection.
What is needed is a non-invasive method of obtaining nucleic acid samples from cells located outside the urinary tract, for use in diagnostic and monitoring applications. The ability to obtain, in a non-invasive way, and analyze specific nucleic acid sequences would have value for purposes including, but not limited to, determining the sex of a fetus in the early stages of development, diagnosing fetal genetic disorders, and achieving early diagnosis of cancer. The presence of Y chromosome gene sequences in the urine of a pregnant woman would be indicative of a male fetus. The presence of gene sequences specific to a certain type of tumor in the urine of a patient would be a marker for that tumor. Thus, such methods would be useful in suggesting and/or confirming a diagnosis.
Methods for analysis of transrenal nucleic acids and are in urine have not been previously described.
All references cited herein are incorporated by reference in their entirety.
The present invention encompasses non-invasive methods of detecting the presence of specific nucleic acid sequences as well as nucleic acid modifications and alterations by analyzing urine samples for the presence of transrenal nucleic acids. More specifically, the present invention encompasses methods of detecting specific fetal nucleic acid sequences and fetal sequences that contained modified nucleotides by analyzing maternal urine for the presence of fetal nucleic acids. The invention further encompasses methods of detecting specific nucleic acid modifications for the diagnosis of diseases, such as cancer and pathogen infections, and detection of genetic predisposition to various diseases. The invention specifically encompasses methods of analyzing specific nucleic acid modifications for the monitoring of cancer treatment. The invention further encompasses methods of analyzing specific nucleic acids in urine to track the success of transplanted cells, tissues and organs. The invention also encompasses methods for evaluating the effects of environmental factors and aging on the genome.
The present invention encompasses methods of analyzing a fragment of fetal DNA that has crossed the placental and kidney barriers, comprising: obtaining a urine sample, suspected of containing fetal polymeric transrenal nucleic acids, from a pregnant female; and assaying for the presence of said fetal polymeric DNA in said urine sample.
The target fetal DNA sequence can be, for example, a sequence that is present only on the Y chromosome. The step of assaying for the presence of unique fetal DNA sequence can be performed using one or more of a variety of techniques, including, but not limited to, hybridization, cycling probe reaction, cleavage product detection, polymerase chain reaction, nested polymerase chain reaction, polymerase chain reaction-single strand conformation polymorphism, ligase chain reaction, strand displacement amplification and restriction fragments length polymorphism. The step of performing the polymerase chain reaction can comprise using primers substantially complementary to a portion of the unique fetal DNA sequence, and the unique fetal DNA sequence can be a sequence that is present in the paternal genome and not present in the maternal genome.
The present invention further encompasses methods having the step of reducing DNA degradation in the urine sample. Reducing DNA degradation can be by treatment with compounds selected from the group consisting of: ethylenediaminetetraacetic acid, guanidine-HCl, Guanidine isothiocyanate, N-lauroylsarcosine, and Na-dodecylsulphate. DNA degradation can further be reduced by taking a urine sample that has been held in the bladder less than 12 hours.
The present invention encompasses methods where DNA in the urine sample is substantially isolated prior to assaying for the presence of a unique fetal DNA sequence in the urine sample. Substantial isolation can be by, but is not limited to, precipitation and adsorption on a resin.
In one embodiment of the present invention, the presence of the particular unique fetal DNA sequence is indicative of a genetic disease.
In some cases, it can be desirable to filter the urine sample to remove contaminating nucleic acids before assaying. In a specific embodiment, the filtering removes DNA comprising more than about 1000 nucleotides.
The present invention also encompasses methods of analyzing a target nucleic acid sequence in urine, comprising: providing a urine sample; and assaying the urine sample for the presence of a target DNA sequence that has crossed the kidney barrier.
The step of assaying for the presence of a target DNA sequence can be selected from the group consisting of hybridization, cycling probe reaction, polymerase chain reaction, nested polymerase chain reaction, polymerase chain reaction-single strand conformation polymorphism, ligase chain reaction, strand displacement amplification and restriction fragments length polymorphism. The step of assaying for the presence of a target DNA sequence can comprise techniques for amplifying the target DNA.
In one embodiment, the target DNA sequence comprises an altered gene sequence, and that altered gene sequence can comprise a modification occurring in tumor cells in specific.
The present invention further encompasses methods having the step of reducing DNA degradation in the urine sample prior to assaying the urine sample for the presence of a target DNA sequence that has crossed the kidney barrier. Reducing DNA degradation can be by treatment with compounds selected from the group consisting of: ethylenediaminetetraacetic acid, guanidine-HCl, Guanidine isothiocyanate, N-lauroylsarcosine, and Na-dodecylsulphate. DNA degradation can further be reduced by taking a urine sample that has been held in the bladder less than 12 hours.
The present invention encompasses methods where DNA in the urine sample is substantially isolated prior to assaying for the presence of a target DNA sequence that has crossed the kidney barrier. Substantial isolation can be by, but is not limited to, precipitation and adsorption on a resin.
In some cases, it is desirable to filter the urine sample to remove contaminating nucleic acids before assaying for the presence of a target DNA sequence that has crossed the kidney barrier. In a specific embodiment, the filtering removes DNA comprising more than about 1000 nucleotides.
The present invention also encompasses methods of analyzing a target nucleic acid sequence in urine, comprising: providing a urine sample, suspected of containing DNA that has crossed the kidney barrier, from a patient; amplifying a target DNA sequence in the DNA that has crossed the kidney barrier, comprising using a primer substantially complementary to a portion of the target DNA sequence that does not occur in cells of the urinary tract of the patient, to make amplified target DNA; and detecting the presence of the amplified target DNA. Amplification can comprise performing a polymerase chain reaction. The target DNA sequence can comprise an altered gene sequence, such as a modification occurring in tumor cells.
The present invention further encompasses methods having the step of reducing DNA degradation in the urine sample prior to amplifying a target DNA sequence in the DNA that has crossed the kidney barrier. Reducing DNA degradation can be by treatment with compounds selected from the group consisting of: ethylenediaminetetraacetic acid, guanidine-HCl, Guanidine isothiocyanate, N-lauroylsarcosine, and Na-dodecylsulphate. DNA degradation can further be reduced by taking a urine sample that has been held in the bladder less than 12 hours.
The present invention encompasses methods where DNA in the urine sample is substantially isolated prior to amplifying a target DNA sequence in the DNA that has crossed the kidney barrier. Substantial isolation can be by, but is not limited to, precipitation and adsorption on a resin.
In some cases, it can be desirable to filter the urine sample to remove contaminating nucleic acids before amplifying a target DNA sequence in the DNA that has crossed the kidney barrier. In a specific embodiment, filtering removes DNA comprising more than about 1000 nucleotides.
The present invention further encompasses a method of determining the sex of a fetus, comprising: obtaining a urine sample, suspected of containing fetal male DNA, from a pregnant female; amplifying a portion of the male DNA present in the urine sample by the polymerase chain reaction, using an oligodeoxynucleotide primer having sequences specific to a portion of the Y chromosome, to produce amplified DNA; and detecting the presence of the amplified DNA.
The present invention encompasses a diagnostic kit for detecting the presence of human male fetal DNA in maternal urine, comprising: reagents to facilitate the isolation of DNA from urine; reagents to facilitate amplification of DNA by the polymerase chain reaction; a heat stable DNA polymerase; and an oligodeoxynucleotide specific for a sequence only occurring on the Y chromosome.
Additionally, the present invention encompasses oligonucleotide primers for the amplification of sequences of the Y chromosome, comprising SEQ ID NO: 3 and SEQ ID NO: 4. A kit for detecting male nucleic acid is also encompasses, this pair of primers. The invention also encompasses a method for detecting Y-chromosome nucleic acid, comprising: carrying out a polymerase chain reaction using these primers and detecting amplified Y-chromosome nucleic acid.
Oligonucleotide probes are also disclosed, including SEQ ID NO: 3 and SEQ ID NO: 4, which can be used for the detection of male nucleic acid.
The present invention further encompasses methods of detecting cancer in a patient, comprising: providing a urine sample from a patient; and analyzing said urine sample for a nucleic acid sequence, indicative of cancer, that has crossed the kidney barrier. In a specific embodiment, said step of analyzing for the presence of said nucleic acid sequence is selected from the group consisting of hybridization, cycling probe reaction, polymerase chain reaction, nested polymerase chain reaction, polymerase chain reaction-single strand conformation polymorphism, ligase chain reaction, strand displacement amplification and restriction fragments length polymorphism. In another embodiment, analyzing for the presence of said nucleic acid sequence comprises amplifying said nucleic acid sequence indicative of cancer.
In another specific embodiment, said analyzing comprises quantifying the number of copies of said nucleic acid sequence.
In one embodiment said nucleic acid sequence contains an anomaly indicative of colon cancer. In another embodiment, said nucleic acid sequence contains mutant K-ras DNA.
It is helpful in some embodiments to include a step to reduce DNA degradation in said urine sample, which in one embodiment encompasses treatment with a compound selected from the group comprising: ethylenediaminetetraacetic acid, guanidine-HCl, Guanidine isothiocyanate, N-lauroylsarcosine, and Na-dodecylsulphate.
In another embodiment the urine sample has been held in the bladder less than 12 hours.
In one embodiment, it is beneficial to substantially isolate said nucleic acid sequence prior to assaying the urine for the presence of a nucleic acid sequence, indicative of cancer, that has crossed the kidney barrier. In alternate embodiments, the nucleic acid sequence is substantially isolated by precipitation or by treatment with a solid adsorbent material. In another embodiment, the urine sample is filtered to remove contaminants, and, in a specific embodiment, the filtering removes DNA comprising more than about 1000 nucleotides.
Also encompassed by the present invention is a method of monitoring transplanted material in a patient, comprising: providing a urine sample suspected of containing nucleic acid from transplanted material; and analyzing said urine sample for a nucleic acid sequence that has crossed the kidney barrier and that was not present in the patient prior to transplantation. In a specific embodiment, the nucleic acid sequence is not present in cells of the urinary tract of said patient.
In a specific embodiment, the analyzing comprises amplifying said nucleic acid sequence with a primer substantially complementary to a part of said nucleic acid sequence that does not occur in cells of the urinary tract of the patient, to make amplified target DNA, and detecting the presence of said amplified target DNA. More specifically, the amplifying can comprise performing a polymerase chain reaction.
In another specific embodiment is included the additional step of reducing DNA degradation in said urine sample, which can be performed in any way known, but, without limitation, includes situations wherein reducing DNA degradation is by treatment with a compound selected from the group consisting of: ethylenediaminetetraacetic acid, guanidine-HCl, Guanidine isothiocyanate, N-lauroylsarcosine, and Na-dodecylsulphate.
In some embodiments, said urine sample has been held in the bladder less than 12 hours.
It is desirable in some embodiments to substantially isolate said nucleic acid sequence. In alternate embodiments, the nucleic acid sequence is substantially isolated by precipitation, and/or by adsorption on a resin.
Additionally, one can filter the urine sample to remove contaminants. In a specific embodiment, this filtering removes DNA comprising more than about 1000 nucleotides.
In yet another embodiment a method of monitoring cancer treatment in a patient is encompassed, comprising: providing a urine sample from a patient; and analyzing said urine sample for the quantity of a nucleic acid sequence, indicative of cancer, that has crossed the kidney barrier.
Further encompassed by the present invention is a diagnostic kit for detecting a genetic mutation indicative of cancer in the DNA of a patient, comprising: reagents to facilitate the isolation of DNA from urine; reagents to facilitate amplification of DNA by the polymerase chain reaction; a heat stable DNA polymerase; and an oligodeoxynucleotide specific for a sequence only occurring in a genetic mutation characteristic of cancer.
Also encompassed by the present invention is a diagnostic kit for detecting DNA from a transplanted material in the urine of a patient, comprising: reagents to facilitate the isolation of DNA from urine; reagents to facilitate amplification of DNA by the polymerase chain reaction; a heat stable DNA polymerase; and an oligodeoxynucleotide specific for a sequence that occurs in the transplanted material, and did not occur in the patient prior to transplantation.

Methods for detection of nucleic acid sequences in urine


Shallow well pumping apparatus comprising a modified walking beam structure in which the beam itself is replaced by a tower intermediate a drive motor and the wellhead, wherein belting, capable of shock absorbtion, is employed as a shock absorbing motion translating and transmitting system for reciprocating a sucker rod to pump fluids from a subsurface deposit.

1. Field of the Invention
Constructors of well pumping apparatus, particularly in the oil fields, have developed equipment which can be acclimated to specific physiological conditions on situs. Of primary concern is the depth of the deposit to be recovered, and the industry has distinguished between "shallow" deposits ranging to a depth of 10,000 feet, and deposits below that range being, not surprisingly, designated as "deep".
Depth of the deposit is an obvious design parameter in that it is determinative of the length, and, thus, the weight of the column of fluid to be raised, which in turn directs the structural strength and power required.
As in any other commercial venture, the cost of doing business has a direct correlation to such factors as down time and costs of repair, and any improvements which results in a lessening of these negative factors inevitably results in a significant improvement in the "bottom line".
Reciprocating type pumps have received wide acceptance in cases where relatively viscous fluids are to be retrieved from subterranean deposits, as the most efficient for such purposes. This is so despite the problems inherent in such equipment when exposed to abrupt changes of direction under load. Such loading factors not only effect the useful life and maintenance schedule for such equipment, but the speed at which such equipment can be operated. Indeed, the operator must strike a meaningful balance between his desire to optimize profit by extracting the most product per unit of time, and the down time costs for maintenance.
In shallow well operations, the standard in the industry is commonly referred to as a "walking beam" pumping unit. Such units employ a powered gear reduction unit which is greatly over designed, simply to be able to withstand shock loading. The transmission drives rotating cranks, which in turn, causes a beam to oscillate about a fulcrum point. A forward end of the beam connects to a stringer to reciprocate the pump in the well.
In recognition of the inevitability of striking the compromise, as aforesaid, by virtue of the deficiencies in existing equipment, the present invention seeks to provide improvements in such equipment so as to permit the operator to overbalance that compromise in favor of profit, principally due to the fact of the 2.1 ratio or, in most cases, double the stroke of most walking beam units.
2. Overview of the Prior Art
One of the prime limiting factors in the performance of existing shallow well equipment is its ability to withstand rapid and repeated changes in loading for extended periods of operation. Virtually all elements of the unit structure are placed under great stress as the pump reaches the bottom of its stroke and begins upwardly. The simplistic answer to this quandary is to simply build the apparatus stronger. There are, however, practical limits, dictated to some extent by size, and to a large extent by cost, to the massiveness of the equipment. Those practical limits have been reached in the familiar walking beam pumping unit.
There have been several efforts to render the "walking beam" unit obsolete, as evidenced by Mayer U.S. Pat. No. 4,761,120. Mayer teaches the concept of substituting a hydraulic ram, which reciprocates on a slide instead of the gear reduction transmission currently in wide use. The ram drives a flexible chain, and uses complex set of hydraulic controls to sense and control movement of the pump stringer. The fallacy of this concept, and those akin to it, is that it is not adaptable, nor compatible with the vast amount of existing equipment, end it is a start from scratch approach. As will be apparent, the "beam" itself is used to translate the rotary motion of the power unit, to the reciprocating motion needed at the well head, and the prior art solution to this translation is to employ reciprocating power, such as the ram, in the first instance. Weaver U.S. Pat. No. 4,512,149 is a variation on the same theme.
Whatley U.S. Pat. No. 4,530,645 presents yet another hydraulic/chain drive combination, and to a limited extent, Bender U.S. Pat. No. 5,018,350 is of interest in that belting is used between the source of motive power and the sucker rod. Bender is, of course, a deep well application, and as in the other relevant art, relies on hydraulic power in a totally different environment, than the present invention.


When a pulling force acts on an insertion joint in a conveying apparatus used for transferring an article conveyed on a main conveying path to a branch conveying path, an endless chain separates from an article support body and the joint state is disrupted. By contrast, when a collar section abuts against an outer end surface on the side of a moving member, an outward concave section inwardly separates from an inclined expanding surface and a tongue piece section can be withdrawn against the elasticity thereof. When the collar section separates from the outer end surface, the outward convex section abuts against the inclined expanding surface and the withdrawal movement of the tongue piece section against the elasticity thereof is prevented. As a result, a strong joint state can be maintained at all time, while ensuring that the endless rotary body and moving member are easily linked and disengaged.

Japanese Patent Application Laid-open No. 2003-128235 discloses a conveying apparatus for transferring articles. A large number of article support bodies oriented in the direction perpendicular to a main conveying path are attached between a pair of left and right endless rotary bodies installed along the main conveying path, a guided body is provided at the rear surface side of article sidewise push bodies that are guided by the article support bodies, and a guide device is provided for guiding the guided body. The endless rotary bodies are of an endless chain system and special linking pins are provided inwardly at the endless rotary bodies. Side members are provided at both ends of the article support bodies and the special linking pins are inserted into and joined with tubular linking sections formed in the side members, whereby both ends of the article support bodies are linked to the endless chain via the respective side members. Furthermore, a mating section that can be externally fitted onto the linking section of the adjacent side member is formed at the other end of the side member.
The linking portions located between the side members are configured by taking into account assemblability and maintainability and also so that they can extend or contract with respect to each other and bend with respect to each other in a reversal section at the start and finish ends of the main conveying path. Thus, a large-diameter portion is formed in the tubular linking section and the mating section is formed as a recess that is open on both, inner and outer, sides and outwardly on the other side. As a result, the circumferential surface of the large-diameter portion is mated with a pair of parallel mating surfaces in the mating section in a state of point contact (linear contact in the left-right direction) in the side view thereof.
However, with the above-described conventional configuration, the article support bodies are linked to the endless chain by inserting the special linking pins and joining them to linking sections of the side member, and such a joint state is difficult to maintain. Thus, for example, when the article support body or endless chain vibrates in the lateral direction and a pull-out force acts at the insertion and joining section, the endless chain withdraws from the article support body and the joint state is disrupted. As a result, the endless chain cannot rotate smoothly, and there is a risk of noise generation by the play or separation from the sprockets.
Furthermore, in the portion where the circumferential surface is in point contact (linear contact) with a flat mating surface, a gap is necessary to provide for smooth extension-contraction or bending in the reversal section. Due to such a gap in the point contact portion, noise is generated by play in the reversal section. Furthermore, the portions of the circumferential surface that are in point contact are easily worn out by repeated extension-shrinkage movement or bending movement, thereby enlarging the gap and increasing the noise produced by play.
Yet another conventional configuration of a conveying apparatus is described in Japanese Patent Application Laid-open No. 6-115680. In this configuration, the linking shaft that links the links in a chain has a large protrusion length. A mounting member is attached to the end surface of a slat, and the linking shaft of the chain is inserted and fixed in a tubular section formed in the plate section of the mounting members. As a result, a large number of slats are attached between a pair of left and right chains, and shoes are provided that are externally fitted on the slats and guided thereby. In a shoe, a face surface section, a rear surface section, and a front surface section are formed integrally, and mounting surface sections with a rear side inclined inwardly are formed at an inclination angle of 30 degrees at both sides of the rear portion of the face surface section. Buffer members made from a urethane resin are detachably attached to the mounting surface sections.
However, with the above-described other conventional configuration, the slats are linked to the chain by inserting and fixing the linking shaft in the tubular section of the mounting member, and such a joint state is difficult to maintain. Thus, for example, when the slat or chain vibrates in the lateral direction and a pull-out force acts at the insertion and fixing section, the chain withdraws from the slat and the joint state is disrupted. As a result, the chain cannot rotate smoothly, and there is a risk of noise generation by the play or separation from sprockets.
Further, because the buffer member is attached only to both sides of the rear portion of the face surface section of the shoe, a gap appears between the rear end of the buffer member provided at a shoe positioned in front and a front end of the buffer member provided at the shoe positioned behind. As a result, in particular, in the case of small articles, the pushing surfaces of the buffer members abut against the eccentric positions (eccentric locations) and the distribution of the articles cannot be performed with good stability. To resolve this problem, a shoe can be increased in size to decrease the front-rear spacing of the shoes (the front-rear gap), but when the shoes themselves are increased in size, there is a risk of clasping an article between the rearmost shoe that advances forward at a side and a front most shoe that is distributed and moves sidewise.


Methods and systems for facilitating transactions between a plurality of liquidity takers (LTs) and a plurality of liquidity providers (LPs) are disclosed. In one example, a computer-implemented method for facilitating transactions between a plurality of LTs and a plurality of LPs is provided. The method may include: (i) assigning a unique identifier to each LP and each LT among a plurality of LPs and LTs in a financial market; (ii) establishing a unique communication channel with each LP and each LT among the plurality of LPs and LTs; (iii) obtaining a plurality of pricing streams from one or more of the plurality of LPs via the unique communication channel established with the one or more of the plurality of LPs; (iv) analyzing LP pricing stream configuration information; and (v) transmitting the plurality of pricing streams to one or more of the plurality of LTs based on the LP pricing stream configuration information.

LTs and LPs frequently have different concerns with regard to the issues affecting the financial market, or markets, in which they transact business. For example, LPs are often interested in providing customized pricing on particular financial products to different LTs. Stated differently, LPs would like to offer a given LT a particular price on a financial product at a particular point in time and offer a different LT a different price on the same financial product at the same point in time. The ability of LPs to provide customized pricing to different LTs frequently serves to advance the LPs' economic objectives.
Conversely, LTs are frequently concerned with obtaining the optimal (i.e., "best") pricing on a given financial product in order to meet their own economic objectives. Typically, this involves LTs seeking out pricing information for a given financial product from a plurality of prospective counterparties (e.g., a plurality of LPs). In this manner, a given LT may identify the optimal pricing relative to the desired financial product by "shopping around." However, conventionally, the process of shopping around for pricing on financial products was arduous, frequently requiring the establishment of separate, direct lines of communication with all prospective counterparties.
For example, in the past, a party wishing to transact a particular foreign exchange (forex) product would often have to contact (e.g., via telephone or the like) several different prospective counterparties in order to evaluate available pricing. This process, requiring the establishment of separate communication channels with each prospective counterparty, demanded a tremendous expenditure of resources. For example, in a scenario where only a single communication channel is available, there is a tremendous waste of time associated with establishing separate, successive communication channels with prospective counterparties. As a corollary, there is a tremendous financial burden imposed upon parties wishing to establish multiple communication channels capable of communicating with prospective counterparties simultaneously. Although the preceding example focused on the trading of forex financial products, those having ordinary skill in the art will appreciate that the instant discussion of the prior art as well as the subsequent teachings of the instant disclosure may apply equally well to the trading of any financial product, including but not limited to, bonds, interest rates, mortgages, financial derivatives, credit products, loans, deposits, money markets, financial futures, contract for difference (CFDs), energy products, precious metals, commodities, other financial assets, and/or other over-the-counter (OTC) products.
Further still, conventional systems and techniques for facilitating the exchange of financial products often required open disclosure of the identities of the participants in the financial market. Returning to the foreign exchange example, in the past, a party wishing to trade a forex product would have to call each prospective counterparty (the one or more counterparties' identities being known to the party wishing to execute the trade) and reveal their identify. By requiring full disclosure of participants' identities, conventional systems and techniques for facilitating the exchange of financial products permitted bias (e.g., bias based upon past dealings with particular market participants) to seep into the market, preventing all participants from receiving accurate, fair pricing information.
There are two primary value propositions that affect the suitability of a particular trading platform for market participants: (1) liquidity optimization and (2) operational efficiency. As known in the art, liquidity optimization may refer to a market participant's ability to access differentiated pricing from multiple market participants for the same financial product. In addition, and as known in the art, operational efficiency may refer to a market participant's ability to connect with a plurality of counterparts through a single logical connection, or the ability to connect one or more LTs with a plurality of LPs through a single logical connection. Conventional trading platforms are largely designed to provide either good liquidity optimization or good operational efficiency, but not both.
For example, referring now to FIG. 1, a conventional bilateral market platform 100 for facilitating multiple, bilateral financial transactions is illustrated. In FIG. 1, pricing streams may be exchanged between a plurality of LPs 120 and a plurality of LTs 130 through the platform 100. As noted above, the pricing streams may be relative to any suitable financial product or products for which a market exists, and in one example may include forex financial products.
The conventional bilateral market platform 100 of FIG. 1 is an example of a trading platform that provides good liquidity optimization, but poor operational efficiency. For example, from a liquidity optimization standpoint, bilateral market platform 100 permits LPs to provide customized pricing to each of the LTs. However, from an operational efficiency standpoint, platform 100 requires each LP to establish separate communication channels with each LT. Similarly, platform 100 requires each LT to establish separate communication channels with each LP. This leads to the inefficiencies noted above.
Further, platform 100 is "transparent" in that the identities of each of the market participants (i.e., LPs 120 and LTs 130) are known to all of the market participants. In many respects, transparency can be beneficial for all of the participants in the market. However, in certain circumstances, pricing made available through platform 100 may be susceptible to bias introduced by virtue of the platform's inherent transparency. That is, market participants 120, 130 interacting through platform 100 may not receive the benefit of "fair" pricing, but rather, may be forced to endure biased pricing based upon the known identities of the market participants.
Another drawback associated with the conventional bilateral market platform 100 is that such a platform is "opt-in." That is, this type of platform requires both LPs and LTs to provide necessary permissions in order to receive pricing information. Accordingly, the necessity to receive permissions from all of the LPs and LTs may grow exponentially as new LPs and/or LTs wish to access the financial market facilitated through the platform 100.
Referring now to FIG. 2, a diagram illustrating a conventional central order book platform 200 is shown. The central order book platform 200 is an example of a trading platform that provides poor liquidity optimization, but good operational efficiency. From a liquidity optimization standpoint, central order book platform 200 performs poorly in that it requires LPs to provide a single price for a given financial product to all of the LTs (i.e., no customized pricing). However, from an operational efficiency standpoint, central order book platform 200 performs well in that it permits a given LP to transact business with a plurality of LTs through a single logical connection (and, consequently, permits a single LT to transact business with a plurality of LPs).
Further, in FIG. 2, the number of bilateral permissions is limited to only one permission for each of the LPs 220 or the LTs 230 via the central order book platform 200. A disadvantage of this type of platform 200 is that LPs 220 can only provide a single pricing to all of the LTs 230, which precludes customized pricing for each individual LT (e.g., LT(1)). In addition, LTs 230 may often prefer to having plural pricing because they may be the benefactor of customized pricing.
Accordingly, new methods and systems for facilitating financial transactions between a plurality of LTs and a plurality of LPs are desired, aimed at alleviating one or more of the above-noted drawbacks.

Methods and systems for facilitating financial exchanges between liquidity takers and liquidity providers


The present invention provides a polishing sheet that can secure a flatness of a material to be polished and can improve a polishing efficiency. A polishing pad 1 has a polyurethane sheet 2 made of polyurethane resin. The polyurethane sheet 2 has large cells 3 with a generally triangular sectional configuration rounded along a thickness direction thereof. Polyurethane resin exists in the polyurethane sheet 2 in a partition wall manner and fine foams 4 are formed in the polyurethane resin. Fine particles 5 added during manufacture of the polyurethane sheet 2 exist inside some of the fine foams 4 and the fine particles 5 are separable from the fine foams. By separating off fine particles positioned at a polishing face P by dummy polishing or the like, fine foams which evenly reserve a polishing liquid containing abrasive particles are formed at the polishing face P.

1. Field of the Invention
The present invention relates to a polishing sheet and a polishing work method, and in particular relates to a polishing sheet having an elastic plastic foam sheet in which fine particles are contained and a polishing work method using the polishing sheet.
2. Description of Related Art
Conventionally, a polishing sheet is used to perform flattening work on a material required for flatness at a high accuracy, such as an optical material such as a lens, a plane parallel plate, a reflecting mirror or the like, a base plate for a hard disc, a silicon wafer, a liquid crystal glass or the like. For example, as a polishing sheet used for accurate flattening work, e.g. for the silicon wafer or the like, a polishing sheet of a nonwoven type obtained by drying a nonwoven sheet after the nonwoven sheet is impregnated with a resin liquid is known (refer to JP05-8178A publication). However, since the polishing sheet of this type has flexibility, there are drawbacks in that a polishing efficiency is low and a roll-off, i.e. peripheral edge portions of a material to be polished are polished more than a central portion thereof, occurs easily. In order to improve the polishing efficiency, there has been disclosed a polishing sheet having an independent foam structure obtained by hollow fine spherical bodies or the like in a plastic material with a high hardness (for example, refer to JP08-500622A publication). However, because a polishing sheet of this type has a high hardness, for example, when the sheet is used in polishing work for an aluminum base plate for a hard disc, there is a drawback in that defects may occur at a surface of the aluminum base plate.
On the other hand, a polishing sheet obtained by pasting a film with a high hardness or the like to an elastic plastic foam of a suede type with a foam structure produced by wet film forming process has been disclosed (for example, refer to JP10-249709A publication). An elastic plastic foam is generally produced by the wet film forming process, and relatively large cells extending in a direction approximately perpendicular to a polishing face are formed in the interior of the elastic plastic foam. Further, elastic plastic exists between adjacent cells in a manner of a partition wall, and relatively small fine foams whose sizes have not been controlled are formed in the partition wall.
Further, a polishing sheet for a silicon wafer where fine particles of barium carbonate are contained in an elastic plastic foam as abrasive particles has been disclosed (for example, refer to JP2001-1270A publication).
However, since the polishing sheet disclosed in the JP10-249709A publication has an elastic plastic foam sheet as a base sheet, there are problems about the polishing efficiency and the roll-off like that in the JP05-8178A publication. Further, when the polishing sheet of the JP2001-1270 publication is used in polishing work for an aluminum base plate, there is such a problem that defects may occur at a surface of the aluminum base plate by the fine particles contained in the polishing sheet. Accordingly, there is a need for development of a polishing sheet which can secure flatness of a material to be polished and has a high polishing efficiency, and which does not cause defects at a surface of the material to be polished, such as an aluminum base plate or the like.

Polishing sheet and polishing work method


Downhole tools are provided with a topographical pattern, and anti-balling material is provided over the topographical pattern. The topographical pattern may be defined by at least one of a plurality of recesses extending into a surface of a body of the tool and a plurality of protrusions protruding from the surface. Downhole tools include an insert disposed within a recess in a body, and the insert comprises an anti-balling material having a composition selected to reduce accumulation of formation cuttings on the tools when the tools are used to form or service a wellbore. Downhole tools include anti-balling material disposed over a porous mass provided over the surfaces of the tools. Methods of forming downhole tools include providing anti-balling material over features on and/or in a surface of a body of a tool. Methods of repairing downhole tools include removing an insert therefrom and disposing a replacement insert therein.

Wellbores are formed in subterranean formations for various purposes including, for example, extraction of oil and gas from the subterranean formation and extraction of geothermal heat from the subterranean formation. Wellbores may be formed in a subterranean formation using a drill bit such as, for example, an earth-boring rotary drill bit. Different types of earth-boring rotary drill bits are known in the art including, for example, fixed-cutter bits (which are often referred to in the art as "drag" bits), rolling-cutter bits (which are often referred to in the art as "rock" bits), diamond-impregnated bits, and hybrid bits (which may include, for example, both fixed cutters and rolling cutters). The drill bit is rotated and advanced into the subterranean formation. As the drill bit rotates, the cutters or abrasive structures thereof cut, crush, shear, and/or abrade away the formation material to form the wellbore. A diameter of the wellbore drilled by the drill bit may be defined by the cutting structures disposed at the largest outer diameter of the drill bit.
The drill bit is coupled, either directly or indirectly, to an end of what is referred to in the art as a "drill string," which comprises a series of elongated tubular segments connected end-to-end that extends into the wellbore from the surface of the formation. Often various tools and components, including the drill bit, may be coupled together at the distal end of the drill string at the bottom of the wellbore being drilled. This assembly of tools and components is referred to in the art as a "bottom hole assembly" (BHA).
The drill bit may be rotated within the wellbore by rotating the drill string from the surface of the formation, or the drill bit may be rotated by coupling the drill bit to a downhole motor, which is also coupled to the drill string and disposed proximate the bottom of the wellbore. The downhole motor may comprise, for example, a hydraulic Moineau-type motor having a shaft, to which the drill bit is mounted, that may be caused to rotate by pumping fluid (e.g., drilling mud or fluid) from the surface of the formation down through the center of the drill string, through the hydraulic motor, out from nozzles in the drill bit, and back up to the surface of the formation through the annular space between the outer surface of the drill string and the exposed surface of the formation within the wellbore.
It is known in the art to use what are referred to in the art as "reamer" devices (also referred to in the art as "hole opening devices" or "hole openers") in conjunction with a drill bit as part of a bottom hole assembly when drilling a wellbore in a subterranean formation. In such a configuration, the drill bit operates as a "pilot" bit to form a pilot bore in the subterranean formation. As the drill bit and bottom hole assembly advances into the formation, the reamer device follows the drill bit through the pilot bore and enlarges the diameter of, or "reams," the pilot bore.
The bodies of downhole tools, such as drill bits and reamers, are often provided with fluid courses, such as "junk slots," to allow drilling mud (which may include drilling fluid and formation cuttings generated by the tools that are entrained within the fluid) to pass upwardly around the bodies of the tools into the annular space within the wellbore above the tools outside the drill string. Drilling tools used for casing and liner drilling usually have smaller fluid courses and are particularly prone to balling, causing a lower rate of penetration.
When drilling a wellbore, the formation cuttings may adhere to, or "ball" on, the surface of the drill bit. The cuttings may accumulate on the cutting elements and the surfaces of the drill bit or other tool, and may collect in any void, gap, or recess created between the various structural components of the bit. This phenomenon is particularly enhanced in formations that fail plastically, such as in certain shales, mudstones, siltstones, limestones and other relatively ductile formations. The cuttings from such formations may become mechanically packed in the aforementioned voids, gaps, or recesses on the of the drill bit. In other cases, such as when drilling certain shale formations, the adhesion between formation cuttings and a surface of a drill bit or other tool may be at least partially based on chemical bonds therebetween. When a surface of a drill bit becomes wet with water in such formations, the bit surface and clay layers of the shale may share common electrons. A similar sharing of electrons is present between the individual sheets of the shale itself. A result of this sharing of electrons is an adhesive-type bond between the shale and the bit surface. Adhesion between the formation cuttings and the bit surface may also occur when the charge of the bit face is opposite the charge of the formation. The oppositely charged formation particles may adhere to the surface of the bit. Moreover, particles of the formation may be compacted onto surfaces of the bit or mechanically bonded into pits or trenches etched into the bit by erosion and abrasion during the drilling process.
In some cases, drilling operations are conducted with reduced or mitigated hydraulics. For example, some rigs may not have large pumps for drilling to the depths required. Furthermore, operators sometimes find it too costly to run higher mud flow rates or find that high flow rates cause more wear and tear to the BHA. Drilling with reduced or mitigated hydraulics has a tendency to cause balling.
Attempts have been made to reduce the likelihood of balling in downhole tools, as disclosed in, for example, U.S. Pat. No. 5,651,420, which issued Jul. 29, 1997, to Tibbitts et al., and U.S. Pat. No. 6,260,636, which issued Jul. 17, 2001, to Cooley et al.; and U.S. Pat. No. 6,450,271, which issued Sep. 17, 2002, to Tibbitts et al.

Downhole tools having features for reducing balling, and methods of forming such tools


Adaptive multi-pathway wireless charging is described. In one aspect, embodiments enable one or more wireless charging pathways to be established concurrently in a wireless charging environment. The wireless charging pathways use same or different frequencies, powers, wireless power transfer (WPT) standards, and WPT configurations. Embodiments for adaptively configuring wireless charging based on detected events or changes in WPT characteristics are also provided.

1. Field of the Invention
The present disclosure relates generally to wireless power transfer (WPT).
2. Background Art
Existing wireless charging approaches use a single wireless charging pathway for all charging needs in an environment. Typically, the wireless charging pathway is enabled by a single coil in the charging device and a single coil in the recipient device. Further, the coil in each device is designed to operate according to pre-defined and fixed WPT standard, amplitude, phase, and frequency.
The present disclosure will be described with reference to the accompanying drawings. Generally, the drawing in which an element first appears is typically indicated by the leftmost digit(s) in the corresponding reference number.

Wireless power transfer adaptation triggers


A protective shield for protecting a feed nozzle encloses, not only the circumference of the feed nozzle, but also encloses and protects the end of the feed nozzle. The protective shield includes an open portion in its end which corresponds to, and surrounds the slit in the end of the feed nozzle. Optimal shape of the open portion is determined by spray visualization tests.

1. Field of the Invention
Fluid Catalytic Converter (FCC) feed nozzles and, in particular, protective shrouds for such feed nozzles.
2. Description of Related Art
In some refineries, there is a problem with erosion of feed nozzle oil heads, which are being eroded from impingement of catalyst. The application of shields around feed guns is being practiced in recent years as a means to reduce catalyst erosion attack on the heads of feed guns.

Protective shroud for FCC feed nozzles and method for designing such shroud


A stain removing composition having a mixture of N-methyl pyrrolidinone and at least one solvent from the group consisting of 3-pentanol, dipropylene glycol monomethyl ether, propylene glycol n-propyl ether, and diethylene glycol monobutyl ether. Preferably the stain removing composition comprises, in percent by weight about 70-90%, N-methyl pyrrolidinone and about 10-30%, in percent by weight, at least one of the solvents from the group described above. In another embodiment, a method of removing a stain from a textile includes the steps of applying the stain removing composition to an area of application. After the composition has been applied to the area of application it is removed with a suction device or other type of absorption device. Water may be applied to the area of application after the composition has been applied to dilute the composition and help in the removal process.

1. Field of the Invention
This invention relates to a composition for removing stains on textiles. More particularly this invention relates to a composition of n-methylpyrrolidone and another co-solvent to effectively and safely remove ink from carpets.
2. Description of the Related Art
Inks, lipstick, lacquer based polishes and/or paints ("residues") have historically been a bane to the existence of carpet owners. This is primarily due to the fact that these products, such as fingernail polish, contain resins that form hard residues when allowed to dry. When left to dry on a textile, such as carpet, the extraction of these resins can be extremely difficult and potentially damaging to the textile itself.
A handful of organic compounds have been identified which have been successfully used as broad spectrum solvents in removing the residues. Unfortunately, the great majority of these have ultimately been found to present undesirable toxicologies and serious hazards to the environment; examples of these compounds include methylene chloride and methyl ethyl ketone (MEK), as well as toluene, xylene, and other aromatics, many of which include the additional hazard of high flammability. For example, although MEK has long been considered a satisfactory solvent from the standpoint of cleaning effectiveness, there is a growing concern that the toxicity and flammability of MEK exposes users to unnecessary risks. Also, because used MEK is considered a threat to the environment, and so is classified as a hazardous waste, the expense associated with the safe disposal of MEK is on the order of 5-10 times greater than the amount which the user initially pays for the solvent. Moreover, because of its relatively high vapor pressure, the loss of MEK to the atmosphere during use is excessive, necessitating the use of large and expensive collection systems such as vacuum hoods.
Because of the concern for the safety, health, and environmental hazards which these known organic solvents thus present, both the federal and state governments are promulgating increasingly stringent criteria which solvent users must comply with. For instance, the California State Legislature limits the use of volatile solvents by requiring that they have a vapor pressure below about 45 mmHg at twenty degrees Celsius. In addition, regulations require that solvents be disposed of in a manner that will not adversely affect the environment. For many users of such solvents, this disposal generally translates into increased operating costs, as noted above.
For the above reasons, a primary consideration for many users of organic solvents has become the toxicity of a particular solvent mixture, and also the hazards which it presents to the environment. This has lead to a number of attempts to find safe substitutes for the hazardous organic solvents which have been used in the past. As an example, methylene chloride has been widely used in industry, especially for formulating paint strippers, lacquer removers, and paint clean-up systems, but it suffers from high volatility which leads to excessive evaporation, contributing to worker exposure and environmental pollution.
Attempts have consequently been made to replace methylene chloride using various, safer organic solvents, but for the most part the replacement solvents create additional problems. Many of the solvents suitable for dissolving oil-based compounds are volatile. These solvents tend to evaporate before they have had sufficient contact time with the affected area and the dissolution process fails. Furthermore, many of these volatile solvents are flammable, which makes suction of the solvent into non-spark proof wet vacuums dangerous. As a result, methods utilizing volatile solvents typically involve blotting or rubbing the treated area, which are much less effective and much more labor intensive than suction techniques.
For example, n-methylpyrrolidone (NMP) has sometimes been found to be a suitable substitute for MEK or methylene chloride in terms of its solvent abilities and it exhibits a very low volatility, which drastically reduces the flammability hazard and evaporative losses. However, NMP alone is sometimes excessively harsh for many applications in that it may cause damage to the underlying substrate. Other compositions of n-methylpyrrolidone include a plant or animal-derived oil as an essential component.
Under the typical and well-known polish extraction techniques, NMP is poured over the affected area in order to dissolve and soften the residue. A commonly recognized aspect of this process is to ensure that the NMP remains in continuous contact with the residue in order to fully dissolve the same. However, prolonged contact of the NMP with the textile may cause a latex adhesive or similar fabric backing to delaminate. This is a common problem resulting from applying such solvents to carpets because typical latex adhesives that bind carpet fibers to the carpet backing material can be degraded relatively quickly by overexposure to the solvent. Too little NMP is not effective at removing stains.
Thus, it can be clearly recognized that there is a need for composition for safely removing stains from textiles, such as carpet, that does not damage the affected textile, and a method for accomplishing the same.

Method for removing stains from textiles


In a first embodiment according to the invention, a method of resolving a dispute includes the step of at least one of a plurality of parties to the dispute providing, via an on-line connection, an input relating to the dispute. Information related to resolution of the dispute is provided, via the on-line connection, to at least one of the parties. The method may further include the step of providing at least a portion of the input from the at least one party in a publicly accessible on-line form that may include an advertising field. In one embodiment, the advertising may be related to the dispute. In one alternative, the method allows at least some people who access the on-line form to interact therewith, such as by voting on the outcome or querying the parties. This method may further include a step of determining which people that access the on-line form are permitted to interact therewith, based, for example, on an assessment of the person's knowledge of the law and/or the facts.

It is common knowledge that lawsuits are expensive, time-consuming, and nerve-wracking. For many people, being involved in a lawsuit is one of the worst experiences of their lives. It is often difficult to find a good lawyer, and often equally or more difficult to be able to afford to pay the lawyer. The legal process is complex and often overwhelming to those not educated in the law, and can include intimidating experiences, such as depositions and appearances as a witness in court.
Because of the logistical, emotional, and monetary expense associated with resolving a dispute via the legal system, many people try to resolve a dispute on their own, by coming to some form of agreement between the parties to the dispute. Alternatively, one party may simply learn to live with a problem, or modify his or her behavior, in an attempt to avoid a confrontation by suppressing the issue. This alternative may lead to poor emotional health, and may also lead to a disproportionate ultimate result as a "last straw" incident that causes the suppressing party to reach an anxiety threshold.
There is a need for a simplified dispute resolution method that allows for relatively fast and inexpensive resolution. Further, there is a need for a simplified process of educating parties to a dispute about the rules regarding their dispute—and about resolutions to similar disputes. Also, there is a constant need for educational, interactive, and/or enjoyable entertainment experiences, such as via the Internet.


The invention relates to a method of treatment of a retroreflective sheet with a treatment composition that comprises a fluorinated compound having one or more silyl groups and an auxiliary compound selected from the group consisting of (i) one or more non-fluorinated compounds of an element M selected from Si, Ti, Zr, B, Al, Ge, V, Pb and Sn and (ii) an organic compound having a Si—H group. The invention also relates to compositions comprising (i) a fluorinated compound comprising one or more silyl groups and (ii) an auxiliary compound selected from the group consisting of organic compounds having a Si—H group.

Retroreflective articles have the ability to return a substantial portion of incident light in the direction from which the light originated. This unique ability has lead to the widespread use of retroreflective articles on clothing worn by highway construction and maintenance workers and fire-fighters. The retroreflective articles displayed on their clothing typically are in the form of retroreflective stripes. The retroreflective stripes typically comprise a layer of microspheres such as glass beads. The retroreflective articles improve the wearers' safety by highlighting their presence.
Several basic types of microsphere-containing retroreflective materials are known. On the one hand, so-called embedded or encapsulated lens type sheetings are known in which the microspheres are covered by a transparent resin layer, i.e., they are fully buried and not exposed to air. The second type of reflective sheeting having microspheres is the so-called open-bead or open-lens material in which the microspheres are partially exposed to air, i.e., they are not completely buried in a binder layer. A third type of microsphere sheeting is similar to the second type, with the exception that a polymeric cover film is heat-sealed intermittently over the microsphere-bearing surface of the reflective sheet. The microspheres in the enclosed lens sheeting are exposed to air (beneath the polymeric cover film), but are not exposed to the elements such as rainfall and are not considered to be open-bead sheeting.
A particular disadvantage of the open-bead reflective sheeting is its reduced reflectivity under rainfall conditions. Moreover, the reflectivity of the sheeting often diminishes after several launderings.
JP 08-309929 discloses treating the exposed glass bead of an open-bead type reflective sheet with a combination of a fluorochemical compound and a silane coupling agent. As the fluorochemical compound, there is taught a perfluoroalkyl acrylic acid ester. Also, it is recommended to additionally use a melamine resin or an isocyanate crosslinking agent so as to further improve the durability of the treatment.
EP 1,262,802 provides a reflective sheet that comprises a reflective element and that comprises microspheres partially exposed at a major surface of the reflective sheet. The reflective sheet has further been treated with a fluorinated silane compound that has a fluorinated group and a silane group having one or more hydrolyzable groups.
While some of the known surface treatments may be capable of providing acceptable levels of initial repellent properties, a loss of repellency is often encountered due to repeated launderings. Further, it would be desirable to improve the reflective properties of the open-bead reflective sheet material under rainfall conditions.
Accordingly, it is desirable to provide a coating composition capable of providing a high durable water repellent coating on a retroreflective sheet. In particular, it is desirable to provide a durable coating wherein the initial reflective and repellent properties are substantially maintained, even under repeated launderings. It will typically also be desired that the treatment composition has good storage stability, minimal environmental disadvantages and can be conveniently manufactured at minimal costs.

Composition of an oligomeric fluorosilane and surface treatment of retroreflective sheet