Disclosed are methods and apparatus for electrographic development which utilize a rotating magnetic core, a toner shell disposed around the rotating magnetic core, and developer compositions disposed on the toner shell which include a hard magnetic material, such as a strontium ferrite. The shell in embodiments has an outer surface with a surface roughness Ra of less than 32 microinches. The methods and apparatus do not require special manufacturing steps to place surface roughness or irregularities on the shell, and, thus, can provide the same or better image quality with relatively less complex manufacturing steps and at reduced cost.

This invention relates to electrography and more particularly it relates to electrographic methods and apparatus using developer compositions comprised of hard magnetic carrier particles for development of electrostatic charge images.
In electrography, an electrostatic charge image is formed on a dielectric surface, typically the surface of the photoconductive recording element. Development of this image is typically achieved by moving it into proximity with a developer composition comprising a mixture of pigmented resinous material, known as toner, and magnetically attractable particles, known as carrier. For a two-component developer comprising a mixture of toner particles and carrier particles, the carrier particles serve as sites against which the non-magnetic toner particles can impinge and thereby acquire a triboelectric charge opposite to that of the electrostatic image, when using a charged area development configuration. When the electrostatic image is in proximity with the developer mixture, the toner particles are stripped from the carrier particles to which they had formerly adhered (via triboelectric forces) by the relatively strong electrostatic forces associated with the charge image. In this manner, the toner particles are deposited on the electrostatic image to render it visible. Both contact toning and non-contact toning are known in the art. The present invention can be used with either contact toning or with non-contact toning, and, hereinafter, the term xe2x80x9ccontactxe2x80x9d, or its equivalent forms, is used for convenience to describe the developer being in proximity to and in developing relationship with the electrostatic image so that development of the image with toner occurs. Therefore, it should be understood that the scope of the present invention is not limited to contact toning. Discharged area development is also known to the art, and the invention is equally applicable to both charged area development and to discharged area development.
It is generally known to apply developer compositions of the above type to electrostatic images by means of a magnetic applicator comprising a cylindrical sleeve of non-magnetic material having a magnetic core positioned within. The core usually comprises a plurality of parallel magnetic strips which are arranged around the core surface to present alternating north and south oriented magnetic fields. These fields project radially, through the sleeve, and serve to attract the developer composition to the sleeve outer surface to form what is commonly referred to in the art as a xe2x80x9cbrushxe2x80x9d or xe2x80x9cnapxe2x80x9d. Either or both of the cylindrical sleeve and the magnetic core are rotated with respect to each other to cause the developer to advance from a supply sump to a position in proximity to the electrostatic image to be developed. After development, the toner depleted carrier particles are returned to the sump for toner replenishment.
Conventionally, carrier particles made of soft magnetic materials have been employed to carry and deliver the toner particles to the electrostatic image. U.S. Pat. Nos. 4,546,060, 4,473,029 and 5,376,492, the teachings of which are incorporated herein by reference in their entirety, teach the use of hard magnetic materials as carrier particles and also apparatus for the development of electrostatic images utilizing such hard magnetic carrier particles. These patents require that the carrier particles comprise a hard magnetic material exhibiting a coercivity of at least 300 Oersteds when magnetically saturated and an induced magnetic moment of at least 20 EMU/gm when in an applied magnetic field of 1000 Oersteds. The terms xe2x80x9chardxe2x80x9d and xe2x80x9csoftxe2x80x9d when referring to magnetic materials have the generally accepted meaning as indicated on page 18 of Introduction To Magnetic Materials by B. D. Cullity published by Addison-Wesley Publishing Company, 1972.
The hard magnetic carrier materials represent a great advance over the use of soft magnetic carrier materials in that the speed of development is remarkably increased with good image development. Speeds as high as four times the maximum speed utilized in the use of soft magnetic carrier particles have been demonstrated.
In the methods taught by the foregoing patents, a developer comprising carrier particles of a hard magnetic material is moved in the direction of the electrostatic image to be developed by high speed rotation of the multi-pole magnetic core within the sleeve, with the developer being disposed on the outer surface of the sleeve. Rapid pole transitions on the sleeve are mechanically resisted by the carrier because of its high coercivity. Chains of carrier particles comprising the nap of the carrier (with toner particles disposed on the surface of the carrier particles), rapidly xe2x80x9cflipxe2x80x9d on the sleeve in order to align themselves with the magnetic field reversals imposed by the rotating magnetic core, and as a result, move with the toner on the sleeve through the development zone in actual contact with, or in proximity and developing relationship to, the electrostatic image on a photoconductor. As mentioned previously, this interaction of the developer with the charge image is referred to as xe2x80x9ccontactxe2x80x9d or xe2x80x9ccontactingxe2x80x9d hereinafter for purposes of convenience. Further, the sleeve may also be rotated to increase the velocity of the developer. See also, U.S. Pat. No. 4,531,832, the teachings of which are also incorporated herein in their entirety, for further discussion concerning such a process.
The rapid pole transitions, for example as many as 467 per second at the sleeve surface when the magnetic core is rotated at a speed of 2000 rpm, create a highly energetic and vigorous movement of developer as it moves through the development zone. This vigorous action constantly recirculates the developer to the sleeve surface and then back to the outside of the nap to provide toner for development. This flipping action also results in a continuous feed of fresh toner particles to the image. As described in the above-described patents, this method provides high density, high quality images at relatively high development speeds.
Various materials have been used to treat the surfaces of the toner component of the developer composition to enhance toner performance in an electrographic process. In recent years, polymers with lower melting points, particularly polyester based resins, have been used as a toner resin since they complement the high speed printing equipment and systems recently developed by the printer/copier industry. Also, various other toner addenda, such as low molecular weight polyethylene and polypropylene waxes, have been used to modify the toner resin and improve performance. Incorporating the foregoing materials into the toner can adversely impact the powder flow properties of the developer composition and eventually image quality, and, therefore, the use of silica and/or other metal oxides as a surface treatment for toner to promote flowability has become increasingly important. Also, silica and other metal oxides have been used to reduce adhesion of the toner particles to the dielectric surface bearing the toned electrostatic image, which reduced adhesion can result in better transfer of the toned image to a receiver for the same, such as a paper sheet.
Such uses of surface treated toner are mentioned, for example, in U.S. Pat. No. 5,286,917, which discloses the use of silica in connection with a one-component developer to increase fluidity of the toner. Silica and other surface treatment agents are said to be used for the same or similar reasons in U.S. Pat. Nos. 5,729,805; 4,982,689; and 4,377,332.
A problem associated with the development systems disclosed in the foregoing patents concerns their use of a stationary, i.e., non-rotating, magnetic core and a developer which includes a soft magnetic carrier and surface-treated toner. For example, these patents disclose that the desired low force of adhesion, low coefficient of friction property, associated with the surface treatment also requires a roughened toning applicator, i.e., sleeve, so that the developer can be transported uniformly into close proximity to the photoconductor and develop an image. U.S. Pat. No. 5,729,805 describes, for example, that a particular type of surface roughness must be present, i.e., they teach that surface roughness Ra must be greater than or equal to 0.2 xcexcm and less than or equal to 5.0 xcexcm with an average spacing between the surface irregularities of from 10 to 80 xcexcm. U.S. Pat. No. 4,982,689 also teaches that the surface of a toning applicator or sleeve is roughened in such a manner so as to allow the developer to be uniformly applied regardless of whether the developer composition is a one component, two-component, magnetic, non-magnetic, insulating, or dielectric developer. The patentees in U.S. Pat. No. 4,982,689 disclose a particular manufacturing process for the toning applicator so as to obtain a desired surface roughness on the sleeve.
As mentioned above, the foregoing patents teach that elaborate roughening steps must be used in the manufacture of toning sleeves in order to impart a desired surface roughness which is said to be required for the methods and apparatus disclosed in the patents. Such roughening steps add greatly to the complexity of the manufacturing process for such apparatus, as well as the cost to manufacture the development system.
As can be seen, it would be desirable to develop improved methods for using developer compositions comprised of surface-treated toners in an electrographic process in order to simplify and reduce the cost of electrographic systems, particularly the complexity and costs associated with steps used to manufacture toning systems.
The foregoing objects and advantages are obtained in one aspect, by a method for development of an electrostatic image utilizing a rotating magnetic core applicator and a developer composition comprised of a hard magnetic material. The method comprises contacting an electrostatic image with at least one magnetic brush comprising:
(a) a rotating magnetic core of a pre-selected magnetic field strength;
(b) an outer nonmagnetic shell disposed about the rotating magnetic core; and
(c) an electrographic developer composition disposed on an outer surface of the shell and in contact with the image, the developer composition comprising a mixture of charged toner particles and oppositely charged carrier particles comprised of a hard magnetic material, the toner particles having dispersed on the outer surfaces thereof at least one surface-treatment agent.
In another aspect, the invention relates to a method for developing an electrostatic image comprising contacting the image with at least one magnetic brush comprising:
(a) a rotating magnetic core of a pre-selected magnetic field strength;
(b) an outer nonmagnetic shell having a smooth outer surface thereon with a surface roughness of roughness Ra of less than about 32 microinches; and
(c) an electrographic developer composition disposed on the smooth outer surface of the shell and in contact with the image, the developer composition comprising a mixture of charged toner particles and oppositely charged carrier particles comprised of a hard magnetic material, the toner particles having dispersed on the outer surfaces thereof at least one surface-treatment agent.
The present invention is based in part on a finding that the performance of a toning station utilizing at least one magnetic brush comprised of a rotating magnetic core, a toning sleeve, and developer composition comprised of a hard magnetic carrier is relatively insensitive to the surface finish of the toning sleeve. Therefore, no special manufacturing steps to place a special surface finish on the toning shell are required to uniformly apply the developer composition and obtain good image quality.
The invention is described in greater detail hereinafter.
The present invention relates to the use of the above-described magnetic brush development system in developing electrostatic images. For example, an embodiment of the invention involves developing an electrostatic image member bearing an electrostatic image pattern by moving the image member through a development zone. A developer composition is also transported through the development zone in developing relation with the charge pattern of the moving imaging member by use of a magnetic brush system comprising an alternating-pole rotating magnetic core of a pre-selected magnetic field strength which is disposed within an outer non-magnetic shell, which shell can also be rotating or stationary. The direction and speed of the core and optionally the shell rotations are controlled such that the developer composition flows through the development zone in a direction co-current with the image member movement. An electrographic dry developer composition is used.
The dry developer composition comprises a toner resin and a hard magnetic carrier. The carrier is preferably a hard magnetic particulate material exhibiting a coercivity of at least about 300 gauss when magnetically saturated and also exhibits an induced magnetic moment of at least about 20 EMU/gm when in an externally applied field of 1,000 gauss. The carrier particles have a sufficient opposite charge and magnetic moment to prevent the carrier particle from transferring to the electrostatic image. The various methods described in U.S. Pat. Nos. 4,473,029 and 4,546,060 can be used in the present invention using the magnetic toner of the present invention in the manners described herein, and these patents are incorporated in their entirety by reference herein.
The electrostatic image so developed can be formed by a number of methods such as by imagewise photodecay of a photoreceptor or imagewise application of a charge pattern on the surface of a dielectric recording element. When photoreceptors are used, such as in high-speed electrophotographic copy devices, the use of half-tone screening to modify an electrostatic image is particularly desirable; the combination of screening with development in accordance with the method of the present invention producing high-quality images exhibiting high Dmax and excellent tonal range. Representative screening methods include those employing photoreceptors with integral half-tone screen, such as those described in U.S. Pat. No. 4,385,823, incorporated in its entirety by reference herein.
Developers in the development system of the present invention are preferably capable of delivering toner to a charged image at high rates and hence are particularly suited to high-volume electrophotographic printing applications and copying applications.
After development, the resulting toned electrostatic image is transferred to a receiver, such as paper, and fixed, i.e., fused thereto, according to known methods.
In more detail, the present invention, in part, relates to a development system. The development system contains a supply of dry developer mixture which includes magnetic toner and hard magnetic carrier particles.
A non-magnetic, cylindrical sleeve, i.e., shell, which can be a stationary shell or a rotating shell, is used for transporting the developer mixture from the supply to the development zone. In embodiments, the sleeve has a smooth surface finish. By xe2x80x9csmoothxe2x80x9d, it is meant a surface roughness Ra of less than 32 microinches or 0.8 microns (which can be attained by conventional grinding methods), and more preferably, less than 12 microinches or 0.3 microns (which may be attained by chrome plating and buffing methods known to the metal fabrication art). Toning shell surfaces with roughness as low as 2 to 6 microinches, or 0.05 to 0.15 microns, such as are obtained by chrome plating and buffing, can also be used. Surface roughness Ra can be determined by profilometry well known to the art.
A magnetic core which includes a plurality of magnetic pole portions is arranged around the core periphery in alternating magnetic polarity relation, which core is disposed within the shell and is rotatable on an axis within the non-magnetic, cylindrical shell. Furthermore, means for rotating the core and optionally the shell are present in order to deliver the developer mixture to the development zone wherein the toner of the developer is transferred to the electrostatic image.
The set up of the development system is preferably a digital printer, such as a Heidelberg DigiMaster(trademark) 9110 printer using a development station comprising a magnetic brush comprising a non-magnetic, cylindrical shell, a magnetic core, and means for rotating the core and optionally the shell as described, for instance, in detail in U.S. Pat. Nos. 4,473,029 and 4,546,060, both incorporated in their entirety herein by reference. The development systems described in these patents can be adapted for use in the present invention. In more detail, the development systems described in these patents preferably use hard magnetic carrier particles. For instance, the hard magnetic carrier particles can exhibit a coercivity of at least about 300 gauss when magnetically saturated and also exhibit an induced magnetic moment of at least about 20 EMU/gm when in an externally applied field of 1,000 gauss.
As previously pointed out in connection with U.S. Pat. Nos. 4,546,060 and 4,473,029, incorporated herein by reference, the patents generally disclose the use of hard magnetic materials as carrier particles. Useful hard magnetic materials include ferrites and gamma ferric oxide. Preferably, the carrier particles are composed of ferrites, which are compounds of magnetic oxides containing iron as a major metallic component. For example, useful compounds include ferric oxide, Fe2O3, formed with basic metallic oxides such as those having the general formula MFeO2 or MFe2O4 wherein M represents a mono- or di-valent metal and the iron is in the oxidation state of +3. Preferred ferrites are those containing barium and/or strontium, such as BaFe12O19, SrFe12O19, and the magnetic ferrites having the formula MO.6 Fe2O3, wherein M is barium, strontium, or lead as disclosed in U.S. Pat. No, 3,716,630, the teachings of which are incorporated in their entirety by reference herein.
The preparation of magnetic ferrites generally and hard, hexagonal crystal structure ferrites (Ba, Sr or Pb) in particular, are well documented in the literature. Any suitable method of making the ferrite particles may be employed, such as the methods disclosed in U.S. Pat. Nos. 3,716,630, 4,623,603 and 4,042,518, the teachings of which are incorporated herein by reference in their entirety; European Patent Application No. 0 086 445; xe2x80x9cSpray Dryingxe2x80x9d by K. Masters published by Leonard Hill Books London, pages 502-509 and xe2x80x9cFerromagnetic Materialsxe2x80x9d, Volume 3 edited by E. P. Wohlfarth and published by North-Holland Publishing Company, Amsterdam, N.Y., Oxford, pages 315 et seq, the teachings of which are also incorporated herein by reference. For example, if the ferrite to be prepared is a hard magnetic strontium ferrite, then from about 8 to 12 parts SrCO3 and 85 to 90 parts of Fe2O3 are mixed with a dispersant polymer, gum arabic, and water as a solvent to form a slurry. The solvent is removed by spray drying the slurry and the resultant green beads are fired at from about 1100xc2x0 C. to about 1300xc2x0 C. to form the desired hard magnetic ferrite material described above. The ferrite material is then deagglomerated and/or milled to reduce the particle size to that generally required of carrier particles, that is, less than 100 xcexcm and preferably from about 3 to 65 xcexcm, and the resulting carrier particles are then permanently magnetized by subjecting them to an applied magnetic field of sufficient strength to magnetically saturate the particles as described herein.
The coercivity of a magnetic material, as mentioned above, refers to the minimum external magnetic force necessary to reduce the induced magnetic moment from the remanance value to zero while it is held stationary in the external field, and after the material has been magnetically saturated, i.e., the material has been permanently magnetized. A variety of apparatus and methods for the measurement of coercivity of the present carrier particles can be employed. For the present invention, a Lakeshore Model 7300 Vibrating Sample Magnetometer, available from Lakeshore Cryotronics of Westerville, Ohio, is used to measure the coercivity of powder particle samples. The magnetic ferrite powder is mixed with a nonmagnetic polymer powder (90 percent magnetic powder; 10 percent polymer by weight). The mixture is placed in a capillary tube, heated above the melting point of the polymer, and then allowed to cool to room temperature. The filled capillary tube is then placed in the sample holder of the magnetometer and a magnetic hysteresis loop of external field (in Oersteds) versus induced magnetism (in EMU/gm) is plotted. During this measurement, the sample is exposed to an external field of 0 to xc2x18000 Oersteds.
The carrier particles may be coated to properly charge the toner particles of the developer. This can be done by forming a dry mixture of the ferrite material with a small amount of powdered resin, e.g., from about 0.05 to about 3.0 weight percent resin based on total weight of the ferrite material and resin, and then heating the mixture to fuse the resin. Such a low concentration of resin will form a thin or discontinuous layer of resin on the ferrite particles.
Various resin materials can be employed as a coating on the hard magnetic carrier particles. Examples include those described in U.S. Pat. Nos. 3,795,617; 3,795,618, and 4,076,857, the teachings of which are incorporated herein by reference in their entirety. The choice of resin will depend upon its triboelectric relationship with the intended toner. For use with toners which are desired to be positively charged, preferred resins for the carrier coating include fluorocarbon polymers such as poly(tetrafluoroethylene), poly(vinylidene fluoride) and poly(vinylidene fluoride-co-tetrafluoroethylene) For use with toners which are desired to be negatively charged, preferred resins for the carrier include silicone resins, acrylic resins, as well as mixtures of resins, such as a mixture of poly(vinylidene fluoride) and polymethylmethacrylate. Various polymers suitable for such coatings are also described in U.S. Pat. No. 5,512,403, the teachings of which are incorporated herein by reference in their entirety.
The magnetic carrier particles can be binder-less carriers or composite carriers.
The first of these carriers comprises a binder-free, magnetic particulate hard magnetic ferrite material exhibiting the requisite coercivity and induced magnetic moment as previously described. This type of carrier is preferred.
The second is heterogeneous and comprises a composite of a binder (also referred to as a matrix) and a magnetic material exhibiting the requisite coercivity and induced magnetic moment. The hard magnetic ferrite material as previously described herein is dispersed as discrete smaller particles throughout the binder. However, binders employed as known to those in the art can be highly resistive in nature, such as in the case of a polymeric binder, such as vinyl resins like polystyrene, polyester resins, nylon resins, and polyolefin resins as described in U.S. Pat. No 5,256,513.
The individual bits of the magnetic ferrite material in the binder should preferably be of a relatively uniform size and sufficiently smaller in diameter than the composite carrier particle to be produced. Typically, the average diameter of the magnetic material should be no more than about 20 percent of the average diameter of the carrier particle. Advantageously, a much lower ratio of average diameter of magnetic component to carrier can be used. Excellent results are obtained with magnetic powders of the order of 5 xcexcm down to 0.05 xcexcm average diameter. Even finer powders can be used when the degree of subdivision does not produce unwanted modifications in the magnetic properties and the amount and character of the selected binder produce satisfactory strength, together with other desirable mechanical and electrical properties in the resulting carrier particle.
The concentration of the magnetic material in the composite carrier can vary widely. Proportions of finely divided magnetic material, from about 20 percent by weight to about 90 percent by weight, of composite carrier can be used as long as the resistivity of the particles is that representative of the ferrite particles as described above.
The induced moment of composite carriers in a 1000 Oersteds applied field is dependent on the concentration of magnetic material in the particle. It will be appreciated, therefore, that the induced moment of the magnetic material should be sufficiently greater than about 20 EMU/gm to compensate for the effect upon such induced moment from dilution of the magnetic material in the binder. For example, one might find that, for a concentration of about 50 weight percent magnetic material in the composite particles, the 1000 Oersteds induced magnetic moment of the magnetic material should be at least about 40 EMU/gm to achieve the minimum level of 20 EMU/gm for the composite particles.
The binder material used with the finely divided magnetic material is selected to provide the required mechanical and electrical properties. It should (1) adhere well to the magnetic material, (2) facilitate formation of strong, smooth-surfaced particles and (3) preferably possess sufficient difference in triboelectric properties from the toner particles with which it will be used to insure the proper polarity and magnitude of electrostatic charge between the toner and carrier when the two are mixed.
The matrix can be organic, or inorganic, such as a matrix composed of glass, metal, silicone resin or the like. Preferably, an organic material is used such as a natural or synthetic polymeric resin or a mixture of such resins having appropriate mechanical properties. Appropriate monomers (which can be used to prepare resins for this use) include, for example, vinyl monomers such as alkyl acrylates and methacrylates, styrene and substituted styrenes, and basic monomers such as vinyl pyridines. Copolymers prepared with these and other vinyl monomers such as acidic monomers, e.g., acrylic or methacrylic acid, can be used. Such copolymers can advantageously contain small amounts of polyfunctional monomers such as divinylbenzene, glycol dimethacrylate, triallyl citrate and the like. Condensation polymers such as polyesters, polyamides or polycarbonates can also be employed.
Preparation of composite carrier particles according to this invention may involve the application of heat to soften thermoplastic material or to harden thermosetting material; evaporative drying to remove liquid vehicle; the use of pressure, or of heat and pressure, in molding, casting, extruding, or the like and in cutting or shearing to shape the carrier particles; grinding, e.g., in a ball mill to reduce carrier material to appropriate particle size; and sifting operations to classify the particles.
According to one preparation technique, the powdered magnetic material is dispersed in a solution of the binder resin. The solvent may then be evaporated and the resulting solid mass subdivided by grinding and screening to produce carrier particles of appropriate size. According to another technique, emulsion or suspension polymerization is used to produce uniform carrier particles of excellent smoothness and useful life.
The size of the magnetic carrier particles useful in the present invention can vary widely, and preferably have an average particle size of less than 100 microns, and more preferably have an average carrier particle size of from about 5 to about 45 microns as may be determined by a Coulter Counter device well-known in the art.
A preferred developer composition is formed by mixing the carrier particles with toner particles in a suitable concentration. Within developers of the invention, high concentrations of toner can be employed. Accordingly, the present developer preferably contains from about 70 to 99 weight percent carrier and about 30 to 1 weight percent toner based on the total weight of the developer; most preferably, such concentration is from about 75 to 99 weight percent carrier and from about 25 to 1 weight percent toner.
At least one surface-treatment agent is employed for the toner in the developer composition according to the invention, and as mentioned above many such surface treatment agents are known and can be employed in connection with the present invention. Such agents can include silica, which may be surface treated itself to render the silica surface hydrophobic in nature, such as those commercially available from Degussa, like R-972, or from Wacker, like H2000. Preferably, the silica is hydrophobized by surface treatment with dichlorodimethylsilane, silicone oil, or hexamethyldisilazane, and has a particle size (prior to hydrophobizing treatment) of at least about 50 m2/g, and more preferably from about 100 to 410 m2/g. as determined by BET analysis. Other surface-treatment agents include, but are not limited to, other inorganic oxide particulates, such as titania, alumina, zirconia, and other metal oxides; and also polymer beads preferably less than 1 xcexcm in diameter (more preferably about 0.1 xcexcm) (where diameter is in terms of volume average diameter), such as acrylic polymers, silicone-based polymers, styrenic polymers, fluoropolymers, copolymers thereof, and mixtures thereof. Mixtures of the foregoing agents are also contemplated.
The amount of the surface treatment agent that can be employed on the toner particles according to the present invention can vary, depending on the particular toner property that is to be modified, but generally the surface treatment agent is used in an amount of from about 0.05 to about 5.0 wt %, based on total weight of the toner employed. More typically, the amount is preferably from about 0.1 to 2 wt %, and more preferably from about 0.15 to about 1.5 wt % based on total weight of the toner.
The foregoing surface treatment agents can be applied to the surfaces of toner particles by conventional surface treatment techniques such as, but not limited to, conventional mixing techniques, such as tumbling the toner particles in the presence of the surface treatment agent. Preferably, the surface treatment agent is distributed on the surface of the toner particles. The surface treatment agent is attracted to the surface of the toner particles and as such can be attached by electrostatic forces or physical means or both. With mixing, preferably uniform mixing is preferred and achieved by such mixers as a high energy Henschel-type mixer sufficient to keep the surface treatment agent from agglomerating or to at least minimize agglomeration. Furthermore, when the surface treatment agent is mixed with the toner particles in order to achieve distribution on the surface of the toner particles, the mixture can be sieved to remove any agglomerated surface treatment agent. Other means to separate agglomerated particles can also be used for purposes of the present invention.
The remaining components of the toner particles, as well as the hard magnetic carrier particles, can be any conventional ingredient. The toner particles can include one or more toner resins that can be optionally colored by one or more colorants by compounding the resin(s) with at least one colorant and any other ingredients. Although coloring is optional, normally a colorant is included and can be any of the materials mentioned in Colour Index , Volumes I and II, Second Edition, incorporated herein by reference. Carbon black can be used in toner particles. The amount of colorant can vary over a wide range, for instance, from about 3 to about 20 weight percent of the polymer and combinations of colorants may be used.
The toner resin itself can be selected from a wide variety of materials including both natural and synthetic resins and modified natural resins as disclosed, for example, in U.S. Pat. Nos. 4,076,857; 3,938,992; 3,941,898; 5,057,392; 5,089,547; 5,102,765; 5,112,715; 5,147,747; and 5,780,195, all incorporated herein by reference. Suitable resins include the crosslinked polymers disclosed in U.S. Pat. Nos. 3,938,992 and 3,941,898, particularly crosslinked or noncrosslinked copolymers of styrene or lower alkyl styrenes with acrylic monomers such as alkyl acrylates or methacrylates. Also useful are condensation polymers such as polyesters. Numerous polymers suitable for use as toner resins are disclosed in U.S. Pat. No. 4,833,060, the teachings of which are also incorporated by reference herein.
The toner can also include a charge control agent as known in the art and any conventional charge control agent can be used. Preferably, the charge control agent for negatively charging toners are metal salts of 3,5 ditertbutyl salicylic acid, and for positively charging toners, quaternary ammonium salts, such as TP 415 from Hodogaya. Specific examples include, but are not limited to, Orient Bontron E-84 and Hodogaya T-77 (an organo-iron chelate).
Waxes may also be incorporated into the toner employed in connection with the present invention. Examples of such waxes include, but are not limited to, polyolefin waxes, such as low molecular weight polyethylene, polypropylene, copolymers thereof and mixtures thereof.
The toner is typically prepared by admixing the resin, colorant, and other desired addenda, which admixture can be heated and milled to disperse the colorant and other addenda in the resin. The heated mass is then cooled, crushed into lumps, and finely ground. The resulting toner particles can range in diameter from about 0.5 to about 25 xcexcm with an average size of from about 1 to about 16 xcexcm, preferably from about 4 to about 12 xcexcm. Preferably, the average particle size ratio of carrier to toner particles lies within the range from about 15:1 to about 1:1. However, carrier-to-toner average particle size ratios of as high as 50:1 are useful. The shape of the toner particles obtained by the foregoing method are irregular and varied in size, but the toner can be any shape, regular or irregular, for use in the invention. Spherically shaped particles can be obtained by spray-drying a solution of the toner resin mixture in a solvent. Alternatively, spherical particles can be prepared by the polymer bead swelling techniques, such as those described in European Patent No. 3905 published Sep. 5, 1979, well as by suspension polymerization, such as by the method disclosed in U.S. Pat. No. 4,833,060, also incorporated in its entirety by reference herein.
The invention is further illustrated by the following non-limiting examples.
In the following examples, all parts and percentages are by weight and temperatures are in degrees Celsius (xc2x0C.), unless otherwise indicated.

Electrographic methods using hard magnetic carrier particles


A lighting panel having a polished major surface and a shaped major surface opposite the first major surface. The shaped major surface has a plurality of longitudinally extending grooves shaped to define, with the first major surface and sides, a plurality of light guides extending from the light receiving end. The light guides have polished hill portions for internally reflecting light striking the polished hill portions and transmitting light along the guides and the grooves having roughened valley portions for causing a portion of the light transmitted along the guides to project outwardly from the major surfaces with the light emitted from the roughened valley portions of the grooves having a uniform distribution across the panel.

There are many applications where it is necessary to provide a large area light source. An example is the illumination of liquid crystal displays such as are found in watches, clocks, cellular telephones, pagers, etc., so that they can be easily read in low ambient light environments. At present, such displays are illuminated with one or more miniature lamps which radiate light. In such displays, the light non-uniformly illuminates the display, making portions of the display dimmer and harder to read than others.


A dental implant system utilizes a threaded implant which is cylindrical in form and has a large number of longitudinal channels so it can be (i) screwed into place in a bore hole in the patient's bone, (ii) pushed into place or (iii) first pushed into place and then turned to anchor it in bone ridges formed when it is pushed into place. Also an implant is given a conical shape it can be used for supporting artificial teeth in a residual ridge crest of a patient by drilling a smaller than normal cylindrical hole in the crest and carefully inserting the conical implant so that the bone is spread and makes additional contact with the implant.

Screw-type implants are now well-known. U.S. Pat. No. 3,499,222 of L. I. Linkow et al. discloses screw-type implants which may be buried in the alveolar ridge crest bone of a patient in an edentulous region. The implant has a threaded lower portion which may be screwed into an opening created in the bone after the tissue has been displaced. A coronal portion protrudes above the bone and is used to support an artificial dental appliance, e.g., an artificial tooth or bridge.
In more recent years, submergible implants have been created in which the threaded portions of the implants can be completely embedded in the bone. They may then be covered with tissue and allowed to remain in place while new bone grows around the implant and through vent holes within the implant. Once it is firmly anchored in new bone, the tissue is reopened and an abutment or upper post portion is screwed into the implant portion and is used to mount the artificial dental device. Submergible implants of this type are disclosed in U.S. Pat. No. 4,713,004 of Linkow et al.
It is advantageous, when installing an implant portion in the patient's jawbone, for the implant to self-tap into the bore hole created in the patient's jawbone because this causes the implant to be better anchored in the bone. As shown in U.S. Pat. No. 4,713,004 of Linkow et al, such an implant may include a cylindrical body with an exterior threaded region that contains a longitudinal channel through a portion of the outer parts of the threads. The channel is wider toward its bottom. One side of the channel is at a right angle to the implant circumference so as to create a cutting edge that creates a self-tapping capability for the implant when it is threaded into a bore or opening in the patient's bone. The channel guides bone chips, created during the threading of the implant, toward the base of the bore in the bone. The bone chips created during the self-tapping operation promote faster bone growth due to their autogenous nature.
The majority of submergible dental implants sold today have an external hexagonal head ("hex-head") which projects from the outer end and is used to couple the implant to an insertion device, e.g. a wrench. This projecting hex-head is also used in attaching the implant to an abutment or post having a matching hex-shaped cavity that receives the projection. Such projecting heads and cavities may be referred to as "coupling surfaces."
Certain areas of the jawbone, such as the thin ("bucco-lingual") residual ridges located primarily in the maxilla, are too thin to allow drilling with a cylindrical drill of The preferred size range in order to create the bore hole. This, in turn, leads to the use of narrower implants. However, due to the decreased surface area of bone contact and their small diameter, these narrower implants are much more likely to fail.


[Problem] To avoid the occurrence of a “DTX-ACK” error or “DTX-NACK” error when a terminal has failed to receive uplink control information. [Solution] A base station (20) of a wireless communication system wherein packet retransmission control is performed by means of a hybrid automatic repeat request (HARQ) is equipped with: a physical uplink shared channel (PUSCH) reception processing unit (104) that, when the transmission timing of HARQ information from a terminal (10) coincides with the transmission timing of a PUSCH transmitted from the terminal (10), receives the HARQ information from the PUSCH and performs a cyclic redundancy check (CRC) on a packet included in the PUSCH; and an HARQ information check unit (105) that performs HARQ-based confirmation of reception at the terminal (10) by receiving the HARQ information checked by the PUSCH reception processing unit (104) and the CRC result.

Regarding physical channels for use in an LTE (Long Term Evolution) method, as one of methods for a mobile communication system, the following five physical channels are defined as physical downlink channels for transmission from a base station to a terminal. Specifically, the five physical downlink channels are constituted by a PBCH (Physical Broadcast CHannel), a PDCCH (Physical Downlink Control CHannel), a PCFICH (Physical Control Format Indicator CHannel), a PDSCH (Physical Downlink Shared CHannel), and a PHICH (Physical Hybrid-arq (automatic repeat request) Indicator CHannel).
A PBCH is a channel for transmitting broadcast information. A PDCCH is a channel for transmitting information for decoding downlink packet data. A PCFICH is a channel for transmitting information for decoding a PDCCH. A PDSCH is a channel for transmitting downlink packet data. A PHICH is a channel for transmitting a CRC (Cyclic Redundancy Check) check result with respect to a PUSCH (Physical Uplink Shared CHannel) to be described later.
Further, in the LTE method, the following three physical channels are defined as physical uplink channels for transmission from a terminal to a base station. Specifically, the three physical uplink channels are constituted by a PRACH (Physical Random Access CHannel), a PUCCH (Physical Uplink Control CHannel), and a PUSCH.
A PRACH is a channel for transmission in order to perform electric power control while synchronizing with an uplink. A PUCCH is a channel for transmitting HARQ information to be described later, or a CQI (Channel Quality Indicator), a PMI (Precoding Matrix Indicator), or an RI (Rank Indicator) indicating a receiving quality. HARQ information is information for notifying a decoding status of a PDSCH as ACK (ACKnowledment)/NACK (Negative ACKnowledment)/DTX (Discontinuous Transmission). A PUSCH is a channel for transmitting uplink packet data, in addition to information included in a PUCCH. Note that one of a PUCCH and a PUSCH is transmitted depending on presence or absence of uplink packet data.
In the LTE method, an operation performed when a terminal receives a signal from a base station is as follows. First of all, a terminal receives a PBCH transmitted from a base station, and then receives a PCFICH. Subsequently, the terminal confirms the number of OFDM (Orthogonal Frequency Division Multiplex) symbols in which a PDCCH is mapped on the basis of a CFI (Control Format Indicator) value detected from a PCFICH, and detects whether or not a PDCCH for the own device is present. Then, when the terminal detects presence of a PDCCH for the own device, the terminal starts receiving a PDSCH by detected downlink control information.
Further, in the LTE method, an operation performed when a terminal transmits a signal to a base station is as follows. When a terminal does not detect presence of a PDCCH for the own device, which is transmitted from a base station, the terminal transmits a PUCCH. On the other hand, when the terminal detects presence of a PDCCH for the own device, the terminal starts transmitting a PUSCH by detected uplink control information. Further, in this case, the base station performs a CRC (Cyclic Redundancy Check) check with respect to the received PUSCH, and transmits the check result to the terminal by a PHICH. The terminal performs uplink packet data re-transmission control on the basis of a CRC check result with respect to a PHICH from the base station.
In the LTE method, a DRX function is employed for the purpose of electric power saving of a terminal. The DRX function is a function of causing a terminal to sleep in a specific state and to stop monitoring a PDCCH for reducing electric power consumption of the terminal. Specifically, it is assumed that a terminal does not receive a PDCCH in an OnDuration section when the terminal is Active, because there is no data to be transmitted or received. In this case, a terminal having a DRX function decodes a PDCCH transmitted from a base station for scheduling only in a next OnDuration section. A section in which a terminal does not decode a PDCCH is referred to as a "DRX section." On the other hand, when a terminal receives a PDCCH in an Active section, the terminal is allowed to activate a DRX Inactivity Timer (extend an Active section), and to continue data communication.
It is assumed that a terminal fails to receive a PDCCH due to a wireless error or the like, despite that a base station has transmitted the PDCCH to the terminal. In this case, when an Active section is extended only in the base station, wireless resources may be useless even when the base station continues scheduling and transmits a PDCCH, because the terminal is in a DRX section.
Various prior arts are proposed relating to the present invention.
For instance, PTL 1 describes packet re-transmission control by an HARQ. In a communication system disclosed in PTL 1, packet missing accompanied by a DTX to ACK error is detected without affecting an existing communication device. In this example, a DTX to ACK error is that a transmission-side communication device erroneously recognizes a DTX, specifically, absence of a re-transmission request from a receiving-side communication device as an ACK. A DTX to ACK error mainly occurs due to a decoding failure of a control channel in a receiving-side communication device.
The communication system disclosed in PTL 1 is constituted by a transmission-side communication device which transmits packets respectively added with sequence numbers and different from one another, and a receiving-side communication device which receives the packets. The receiving-side communication device includes a receiving unit and a determination unit. The receiving unit receives packets with use of a plurality of processes. The determination unit detects missing of reception of any one of the packets in the receiving unit on the basis of the sequence numbers. In this case, the determination unit determines whether or not the one packet is missing accompanied by a DTX to ACK error in the transmission-side communication device, on the basis of a use status of each process.
Further, PTL 2 discloses a technique capable of limiting a probability of a DTX to ACK error to an allowable level. A base station disclosed in PTL 2 includes an interface and a processor. The interface is configured to receive information included in acknowledgement/negative acknowledgement (ACK/NACK) resources in an uplink control channel, and relating to a generated bundled ACK/NACK value and relating to the number of downlink grants detected in a receiving bandwidth of a user device. The processor is configured to execute ACK/NACK/DTX (discontinuous transmission) detection on the basis of the received information, and to determine whether or not the detected ACK/NACK state reflects a proper ACK/NACK on the basis of the ACK/NACK/DTX detection.
PTL 3 discloses a re-transmission control method and a receiving-side device capable of minimizing packet missing when a transmission-side device erroneously detects delivery acknowledgement information transmitted via an HARQ feedback physical channel. The transmission-side device disclosed in PTL 3 includes an MAC multiplexing unit, an MAC header adding unit, and a shared physical control channel receiving unit. The receiving-side device includes a shared physical control channel transmitting unit.
The MAC header adding unit generates a protocol data unit (packet) to be transmitted on a transport channel, which is multiplexed in a shared physical data channel by adding an MAC header and an error-correcting code (such as a CRC) to user data transmitted from the MAC multiplexing unit. The shared physical control channel receiving unit receives delivery acknowledgement information such as an ACK/NACK via a shared physical control channel (HARQ feedback physical channel), and notifies an associated HARQ process of the information. The shared physical control channel receiving unit judges that the device is in a DTX state when the device does not receive delivery acknowledgement information with respect to each packet within a predetermined period of time. The shared physical control channel transmitting unit transmits delivery acknowledgement information (ACK/NACK) notified from each HARQ process via the shared physical control channel (HARQ feedback physical channel).
PTL 4 discloses a base station device and a communication control method capable of appropriately performing a scheduling process and an HARQ process in an LTE downlink and in an LTE uplink. The base station device disclosed in PTL 4 includes a baseband signal processing unit. The baseband signal processing unit includes a layer 1 processing unit.
The layer 1 processing unit performs demodulation and decoding of a CQI or delivery acknowledgement information to be mapped in an uplink control channel transmitted by an uplink. The layer 1 processing unit performs, in the subframe, a process of receiving delivery acknowledgement information or a CQI mapped in a physical uplink control channel (PUCCH) located on both sides of a system band, when delivery acknowledgement information or a CQI relating to a mobile station which does not receive user data is received in an uplink. Then, the layer 1 processing unit notifies an MAC processing unit of the delivery acknowledgement information or a receiving result of a CQI.
The delivery acknowledgement information described above is one of an ACK, a NACK, and a DTX. The DTX means that "a mobile station actually did not deliver delivery acknowledgement information." When the delivery acknowledgement information is determined to be a 'DTX', the base station device re-transmits a downlink shared channel. Note that the scheduling process designates a process of sorting out mobile stations which receive user data with use of a shared channel in a downlink of the subframe.
PTL 5 discloses a terminal device and a re-transmission control method capable of improving characteristics of a response signal (an ACK/NACK signal, or "A/N") having poor transmission characteristics. A base station disclosed in PTL 5 includes a data transmission control unit, a modulation unit, a PUCCH extraction unit, and a re-transmission control signal generation unit.
When the data transmission control unit receives a NACK or a DTX with respect to downlink data transmitted from the re-transmission control signal generation unit with use of a certain downlink unit band, the data transmission control unit outputs holding data associated with the downlink unit band to the modulation unit. When the data transmission control unit receives an ACK with respect to a downlink transmitted from the re-transmission control signal generation unit with use of a certain downlink unit band, the data transmission control unit deletes holding data associated with the downlink unit band.
The PUCCH extraction unit extracts, from a PUCCH signal included in a receiving signal, a signal in a PUCCH region associated with a bundled ACK/NACK resource, which is notified to a terminal in advance. Further, the PUCCH extraction unit extracts, from a PUCCH signal included in a receiving signal, an A/N resource associated with a CCE (Control Channel Element) occupied by a DPCCH used in transmitting downlink allocation control information (DCI), and a plurality of PUCCH regions associated with a plurality of A/N resources notified to a terminal in advance.

Base station, reception confirmation method, and storage medium wherein program is stored


A foaming composition is provided comprising a particulate ingredient having a plurality of internal voids containing entrapped supercritical fluid having a critical temperature of at least about 10° C. Additionally, a method is provided for preparing such a foaming composition. A supercritical fluid having a critical temperature of at least about 10° C. is contacted with a particulate ingredient having a glass transition temperature above ambient temperature at a temperature above the glass transition temperature of the particulate ingredient, wherein the particulate ingredient comprises a plurality of internal voids. The particulate ingredient is held at the temperature above the glass transition temperature of the particulate ingredient for a period of time effective to allow transfer of the supercritical fluid into the plurality of internal voids of the particulate ingredient. Subsequently, the temperature is reduced to below the glass transition temperature of the particulate ingredient, thereby entrapping at least a portion of the supercritical fluid in the plurality of internal voids of the particulate ingredient.

A number of conventionally prepared food items, for example, cappuccino, milk shakes, and certain soups, desirably include froth or foam. In order to accommodate an increasing demand for the convenience of consumer prepared instant food alternatives, manufactures have developed a variety of instant food products which give consumers the food products they desire from a convenient instant food product having the same or similar characteristics as conventionally prepared food items. One challenge for manufacturers is how to produce an instant food product having a desirable froth or foam.
One technique used to manufacture an instant food product with foam is through the use of powdered foaming compositions that produce foam upon reconstitution in a liquid. Foaming powder compositions have been used to impart froth or foamed texture to a wide variety of foods and beverages. For example, foaming compositions have been used to impart froth or foamed texture to instant cappuccino and other coffee mixes, instant refreshing beverage mixes, instant soup mixes, instant milkshake mixes, instant dessert toppings, instant sauces, hot or cold cereals, and the like, when combined with water, milk, or other suitable liquid.
Some examples of gas-injected foaming creamers which can be used to impart foam or froth are disclosed in U.S. Pat. No. 4,438,147 and in EP 0 458 310. More recently, U.S. Pat. No. 6,129,943 discloses a foaming creamer produced by combining a gasified carbohydrate with protein and lipid. Using this technology, it was possible to eliminate gas injection of the liquid creamer composition prior to spray drying.
EP 0 813 815 B1 discloses a foaming creamer composition which is either a gas-injected foaming creamer or a creamer containing chemical carbonation ingredients which contains in excess of 20% protein by weight. The powder described has, as essential ingredients, protein, lipid and filler material, the filler especially being a water-soluble carbohydrate. The high content of protein is needed to obtain a whipped cream-like, tight foam having spoonability.
Another foaming composition is described in U.S. Pat. No. 6,713,113 which discloses a powdered soluble foaming ingredient comprising a matrix containing carbohydrate, protein, and entrapped pressurized gas. However, powdered ingredients containing both carbohydrate and protein are susceptible to nonoxidative browning reactions that can adversely affect the appearance, flavor, and shelf life of packaged food products. These complex chemical reactions occur between proteins and carbohydrates, especially reducing sugars, to form polymeric pigments that can severely discolor and diminish the flavor quality of food products. U.S. Patent App. Publication Nos. 2006/0040033 and 2006/0040034 describe non-carbohydrate foaming compositions and non-protein foaming compositions, respectively, which provide resistance to undesirable browning and impaired flavor quality.
Disadvantages of existing foaming compositions and the manufacturing methods thereof include the relatively long processing times required to introduce the gas into the structure of the foaming composition and the high raw material costs resulting from wasted gas and other materials. Thus, there remains a need for foaming compositions for use in instant food and beverage products that exhibit desirable foaming characteristics upon reconstitution and that may be prepared by methods that desirably reduce processing times and raw material costs. The present invention provides these and other benefits, as will be apparent from the following description of embodiments of the present invention.

Foaming compositions and methods of making the same


A semiconductor device is disclosed. One aspect provides a semiconductor device that includes a semiconductor chip including a first face and a second face opposite the first face, an encapsulant including inorganic particles encapsulating the semiconductor chip, a first metal layer attached to the first face of the semiconductor chip, a second metal layer attached the second face of the semiconductor chip, and electrically conducting material configured to connect the first metal layer with the second metal layer.

Market demands for smaller and more functional electronic devices have driven the development of semiconductor devices, including semiconductor packages, and entire systems disposed on a chip. In general, semiconductor packages include at least one semiconductor chip covered with a plastic or epoxy encapsulation material. Some electronic devices are employed in high temperature applications, for example, automotive applications, and operate in demanding environments.
Thermal cycling of the semiconductor package has the potential to separate the semiconductor chip from the encapsulation material, due in part to these components having different thermal coefficients of expansion. The separation at the interface of the semiconductor chip and the encapsulation material provides an opening for the ingress of moisture. The moisture ingress undesirably corrodes electrical connections on the chip and has the potential to warp or otherwise affect the dimensions of the chip.
For these and other reasons there is a need for the present invention.


An improved temperature regulated wall ventilator comprising a housing defining an air flow passageway therethrough, a plurality of louvers mounted in side by side relation in the housing passageway for pivotal movement about their longitudinal axes to open and close the air flow passageway, and temperature responsive helical spring control means located in the air flow passageway on an inner end portion of a stub shaft mounted on the housing. One end of the helical spring is attached to one of the louvers, and the other end of the spring is operatively attached to the stub shaft to prevent its relative rotation with respect thereto. The stub shaft is mounted in an opening of the housing wall, and, prior to installation of the ventilator in a wall opening, the stub shaft may be partially retracted from the housing wall and rotated to cause compression or contraction of the spring about its longitudinal axis, thereby varying the pressure of the spring on the louvers to establish a desired temperature at which the louvers are opened or closed.

It is well known to provide ventilation to enclosed spaces of buildings, such as crawl spaces and basements, by the use of ventilators located in openings of the foundation walls. Such ventilators are generally provided with adjustable closure means, such as shutters or louvers, to control the flow of air to and from the enclosed space, depending on temperature, weather conditions or seasonal changes. Generally such foundation wall ventilators are secured in the wall opening during construction of the foundation wall by cement, mortar, or other fastening materials.
It is also known to provide temperature responsive control of the closure shutters or louvers of such ventilators by the use of bimetallic temperature responsive springs which may be operatively connected between the fixed housing of the ventilator and the movable shutters in such a way that expansion or contraction of the springs due to temperature changes causes pivotal movement of the shutters from open to closed positions in the air flow passageway through the ventilator housing. Typical of such devices are disclosed in the following patents:
______________________________________ French 1,377,998 U.S. 3,068,776 U.S. 2,187,767 U.S. 3,195,441 U.S. 2,241,108 U.S. 3,368,756 U.S. 2,551,965 U.S. 3,436,016 U.S. 3,027,090 U.S. 3,528,606 ______________________________________
Above-mentioned U.S. Pat. No. 3,436,016 particularly discloses a temperature responsive foundation ventilator construction having bimetallic spring operatively connected between a fixed shaft and movable shutters to provide for controlled movement thereof in response to predetermined temperature changes in the air passing through the shutter.
Although many such temperature responsive spring controlled louvered ventilators are known in the field of the art, there is an ever present need to provide a temperature-responsive, automatically controlled wall ventilator which can be more easily or economically manufactured to provide improved reliability of performance in use.

Temperature regulated wall ventilator construction


A communication system comprising a network and an information multiplexing device for transmitting information cells from one of its accesses to another access. The multiplexing device includes a plurality of access terminals for transmitting information signals to a destination at a predetermined rate, at least one connecting terminal for one of the access terminals, a plurality of service circuits having queue elements for storing data and a common data line interconnecting the data outputs of the service circuits with the connecting terminal.

A requirement posed on this type of device is that the rate of information signals to be carried does not exceed the rate the user has reserved in the network and for which he pays. If this rate is disregarded, the network to which the device is connected will become "a policing network" and will reject the excessive cells and the link will be disturbed much to the user's annoyance. This mechanism is known under the name of Usage Parameter Control UPC. This policing function is described in Martin de Prycker, Asynchronous Transfer Mode (England: Ellis Horwood Limited, 1991, 219-226.
A communication system of the type mentioned in the opening paragraph of this Application is known from the article: "DISTRIBUTED MERGER FOR ATM" by R. Rocha et at., published in International Conference on INTEGRATED BROADBAND SERVICES AND NETWORKS, dated Oct. 15-18, 1990.
This known communication system has the drawback that no measure is taken as regards said requirement.
The present invention proposes a communication system of the type mentioned hereinbefore which satisfies this requirement.

ATM information system and multiplexer for assigning and controlling access time


An electric vehicle includes an electric motor, an inverter that supplies electric power to the electric motor, a radiator that cools a coolant, a coolant passage that is configured to circulate the coolant through the electric motor, the inverter and the radiator, a plurality of liquid leakage detection sensors (flow sensors) provided in the coolant passage, a plurality of valves provide in the coolant passage, and a controller. The controller is configured to close valves provided at two locations, between which a portion where leakage of the coolant is detected by the liquid leakage detection sensors is located.

1. Field of the Invention
The invention relates to an electric vehicle having a traction electric motor, such as a pure electric vehicle, a hybrid vehicle, or a fuel cell vehicle.
2. Description of Related Art
An electric vehicle includes a traction electric motor, and an inverter that converts direct-current power of a battery into alternating-current power that is suitable to drive the electric motor. Since the inverter handles large current in order to drive the electric motor, the inverter produces a large amount of heat. That is, the electric vehicle has at least two heat-producing sources that include an electric motor and an inverter. Each heat-producing source is provided with a cooling apparatus in order to restrain temperature rise of the heat-producing source.
Typically, liquid (water, long life coolant (LLC) or oil, for example) is used as a coolant. If the coolant leaks, the cooling capability significantly declines. A technology that detects leakage of a coolant is proposed in Japanese Patent Application Publication No. 2008-309134 (JP 2008-309134 A). Furthermore, a technology that lessens the amount of leakage of a coolant caused when the coolant passage is damaged is proposed in Japanese Patent Application Publication No. 2010-276035 (JP 2010-276035 A).


A video game combines finger swiping to hurl a projectile at a target, with strategic elements arising from various combinations of player and target characteristics. User actions such as a direction of finger swipe against a touchscreen, a speed of finger swipe against the touchscreen, and/or a length of finger swipe against the touchscreen, may determine the trajectory and/or force of the projectile. The player may dynamically select specific roles from a plurality of cards available in a deck, with the particular role determining game parameters such as offensive effectiveness and defensive strength. The game may incorporate one or more strategic concepts such as the ability to combine roles, the evolution of roles over time, and the selective enlistment of allies.

The present invention relates to video games and methods and systems therefor.
Video games are popular pastime activities. In the past, video games were played on arcade machines, televisions, and computers. More and more video games are being played on portable devices, such as mobile phones and tablets. The video games that are played on portable or mobile devices are sometimes referred to as "mobile video games." The portable devices (or mobile devices) typically include a touch sensitive display area (or touchscreen) whereon players can view videos and input commands. Many mobile video games enable players to play the games by inputting commands on the touchscreen. Video games that involve the hurling of a projectile at a target by inputting commands on a touchscreen are known. Examples of such games are ANGRY BIRDS and PAPER TOSS. Such games are typically simple in nature, with success depending upon mastery of a relatively few, low-level tactical skills and concepts.
With few opportunities available for the exercise of more complex tactical thinking, however, users may quickly tire of such conventional target games. Accordingly, there is a need in the art for a target games calling for the exercise of strategic judgment by the player.

Target game incorporating strategy elements


An adjustable table is described having three support structures arranged symmetrically around the perimeter of the table. Each support structure is supported on a base by means of a two dimensional joint, such as a leaf spring, having an axis of rotation tangential to a circle centered at a central point of the table. Each support structure supports the table by means of a three dimensional joint such as a ball in socket joint. Each support structure includes a threaded spindle and a rotatable threaded bolt for adjusting the separation between the table and the base.

The present invention relates to an adjustable table which is tiltably positioned by adjusting elements over a fixed base, and particularly to an adjustable table for use with precision measuring devices.
It is a known practice from West German DE-AS No. 2,515,828, to support an adjustable table of the above-mentioned type by means of three spheres arranged to bear on a fixed base in a conical depression, a prismatic groove and a plane surface, respectively. By adjusting the last two spheres, which lie on oblique prisms of the adjustable table, the table can be swung in two vertical planes perpendicular to one another about the sphere arranged in the conical depression. This arrangement presents the disadvantage that the three support points differ in rigidity, that thermal expansion can cause decentering of the table, and that the point contacts between the balls and the prismatic groove and the plane surface are susceptible to wear and deformation.
When three spheres are mounted on the fixed base and are positioned in three prisms running radially with respect to the center of the adjustable table, substantially no decentering of the table results from temperature changes, but in this case friction at the resting points must be overcome. This friction may generate forces in the table which can affect its levelness. Furthermore, wear occurs at the point contacts between the spheres and the prisms, and this wear is increased when the table is adjusted by a grinding of the spheres into the prism surfaces, so that the spheres are no longer freely shiftable in the prisms and for that reason a statically determined rest position is no longer provided.
In West German DE-AS No. 2,248,535 there is described an adjustable table that includes three plates lying one upon another, which are slidable in the horizontal plane by means of spheres placed in prismatic guides via adjusting elements, and in the vertical plane are tiltably borne by means of further spheres which bear on plane surfaces and on slopes. This arrangement is also subject to wear at the point contacts between the spheres and the plane surfaces and the prisms.
From West German DE-OS No. 2,543,564 one learns of a table that is tiltably supported on a rigid intermediate body by means of obliquely disposed bearing elements, wherein the intermediate body is horizontally shiftable by means of roller bodies with respect to a base. In West German DE-OS No. 1,772,599 there is shown an adjusting arrangement having a row of plates disposed one over another. In each case two plate surfaces lying opposite one another are designed for straight-line flat horizontal displacement and, in each case, two oppositely lying surfaces are provided with a construction for swinging about a horizontal axis. These two arrangements present the disadvantage that the adjustable surface is decentered by the swinging movement, so that a subsequent centering must be performed.


An optical multi-layer structure for a flat panel display device is provided. The optical multi-layer structure includes a first optical layer, a second optical layer, a surface strengthening layer, and an adhesive layer. The first optical layer converts a light into a first polarized light. The second optical layer is disposed on the first optical layer and converts the first polarized light into a second polarized light. The surface strengthening layer is disposed on the second optical layer. The adhesive layer is disposed between the second optical layer and the surface strengthening layer, and is in direct contact with the second optical layer and the surface strengthening layer. A flat panel display device having the optical multi-layer structure is also disclosed.

1. Field of the Invention
The present invention relates to an optical multi-layer structure, and in particular relates to an optical multi-layer structure having improved surface hardness and a flat panel display (FPD) having the optical multi-layer structure.
2. Description of the Related Art
Due to being thin and light weight, and having low power consumption, flat panel display devices such as liquid crystal display devices have solved problems found in cathode ray tube (CRT) display technologies and are widely used in electronic devices, for example laptops, personal digital assistants (PDA), electronic books, projectors, and mobile phones.
In the current market, flat panel display devices are typically two-dimensional (2D) flat panel display devices. With the development of new display technologies, three-dimensional (3D) flat panel display devices have also emerged. Referring to FIG. 1, a cross section of a conventional flat panel display 10 is illustrated. The flat panel display 10 comprises a backlight module 12 and a display structure 16 disposed above the backlight module 12. The display structure 16 may be a liquid display structure or an organic light-emitting display structure. Further, the display structure 16 typically has polarizing films 14 and 18 adhered to its back side and front side, respectively, to convert a light 12a from the backlight module 12 into a linear polarized light. When applying the flat panel display 10 in a stereoscopic or three-dimensional display, a user viewing the display has to wear a viewing device (for example, shutter glasses) to make sure that the user's right eye and left eye can perceive correct images, respectively. Further, an optical film 20 is additionally adhered onto the polarizing film 18 on the front side of the display structure 16 to convert the linear polarized light into a circular polarized light. However, the optical film 20 does not have sufficient surface hardness (i.e. having a pencil hardness lower than 1 H), and as a result, the polarizing film of the three-dimensional flat panel display devices does not satisfy surface hardness requirements (i.e. the pencil hardness being equal to or greater than 3 H).
Thus, an optical multi-layer structure for flat panel display devices that improves or solves the problems described above is needed.

Display device and optical multi-layer structure for display device


Highly dispersed lithium titanate crystal structures having a thickness of few atomic layers level and the two-dimensional surface in a plate form are supported on carbon nanofiber (CNF). The lithium titanate crystal structure precursors and CNF that supports these are prepared by a mechanochemical reaction that applies sheer stress and centrifugal force to a reactant in a rotating reactor. The mass ratio between the lithium titanate crystal structure and carbon nanofiber is preferably between 75:25 and 85:15. The carbon nanofiber preferably has an external diameter of 10-30 nm and an external specific surface area of 150-350 cm2/g. This composite is mixed with a binder and then molded to obtain an electrode, and this electrode is employed for an electrochemical element.

A carbon material etc. that stores and releases lithium is currently used as the electrode for lithium batteries, but there is a risk of decomposition of the electrolytic solution since the negative electrode potential is lower than the reductive decomposition potential of the electrolytic solution. Accordingly, as described in Patent Documents 1 or 2, the use of lithium titanate having lower negative electrode potential than the reductive decomposition potential of the electrolytic solution is being investigated, but lithium titanate has a problem of low output property. Accordingly, attempts are being made to improve output property by an electrode in which lithium titanate is made into nanoparticles and supported on carbon.
Patent Document 1: Japanese Patent Application Laid-open No. 2007-160151
Patent Document 2: Japanese Patent Application Laid-open No. 2008-270795
The inventions described in these Patent Documents are methods for applying sheer stress and centrifugal force to a reactant in a rotating reactor to allow promotion of chemical reaction (generally referred to as mechanochemical reaction), thereby yielding dispersed lithium titanate supported on carbon. In this case, for example, titanium alkoxide and lithium acetate which are the starting materials of lithium titanate, a carbon such as carbon nanotube or carbon black, and acetic acid etc. are used as reactants.
Although the electrodes that use carbon supporting lithium titanate crystal structures described in these Patent Documents exert superior output property, there are recent demands to further improve the output property and to improve the electric conductivity in this type of electrode.

Lithium titanate crystal structure, composite of lithium titanate crystal structure and carbon, method of production thereof, and electrode and electrochemical element employing said composite


A backlighted display system includes a liquid crystal display, a flat light guide behind the display, and light emitting diodes (LED's). The light guide is a molded slab of clear polycarbonate material with two planes depressed into its rear surface. Four segmented bordering surfaces are approximately arcuate in shape. The depressed planes, the segmented bordering surfaces, and the rear surface are coated with a reflective white paint. LED holders are integrally molded with the light guide. A central portion of the front surface is optionally textured. The display system provides thin construction with even light distribution across the width of the display, low power consumption, and good outdoor visibility at dusk or dawn.

This invention relates to the field of display systems and more particularly to backlighted liquid crystal display systems.
Displays which are capable of forming images of characters or patterns may be broadly broken down into two different categories, active and passive. In active displays, such as light emitting diode (LED) displays, the images are composed of individual diodes which emit their own light. Since active displays are typically characterized by high power consumption, the choice for low power applications, such as portable calculators, watches, portable radios, and pocket pagers, is typically the passive display. An example of a passive display is the liquid crystal display (LCD). Rather than emitting their own light, LCD images merely reflect or absorb light, therefore, ambient sun light or room light is normally required to view the display. When the ambient light intensity is not sufficient to illuminate the display, however, an internal supplemental illumination means is typically provided. In a simple supplemental illumination system one or more light sources, typically incadescent lamps, are placed behind or in front of the display. One of the disadvantages of the simple supplemental illumination system is the creation of "hot spots". "Hot spots" are areas of the display where the light intensity is considerably greater than in other areas. "Hot spots" result in poor display readability. To correct the problem of "hot spots" and to more evenly distribute the light coming from the light sources, a light guide may be positioned behind the liquid crystal display.
A prior art light guide is illustrated in FIGS. 1 and 2. The light guide is normally made from a slab of transparent plastic material generally designated as 10 and has an upper surface 12, a lower surface 14, and four bordering surfaces 16, 18, 20 and 22. Light sources 24 and 26 are positioned respectively in notches 28 and 30 which are located at opposite ends of the slab 10. The bottom surface 14 has two planes 32 and 34 depressed into the bottom surface, thereby forming a V-shaped wedge. The top surface 12 has two areas 36 and 38 which are covered with a reflective coating. A reflective coating also covers the bottom surface 14, the depressed planes 32 and 34, and the bordering surfaces 16, 18, 20 and 22 with the exception of notches 28 and 30 which remain transparent.
In operation, light emitted from the light sources 24 and 26 travels the length of the light guide towards the planes 32 and 34, strikes the reflective surface thereon, and is reflected up through the transparent surface 12. The liquid crystal display (not shown) is situated above front surface 12 and the light passing through the front surface 12 also passes through the liquid crystal display, thereby improving display visibility.
Although this prior art light guide more evenly distributes light across the display then the simple supplemental illumination system, it also has several disadvantages, one of which is its thickness. Thinness is extremely important in the design of small watches, pocket calculators, pocket pagers, portable radios and any other device in which small packaging size is paramount. An acceptable design of a 1.8 inch long prior art guide may only be made as thin as 0.070 inches as measured at the thickest point. Any attempt to make the prior art light guide any thinner, creates an unacceptable distribution of light which results in a wide discrepancy between the intensity of the light emitted at one point on the front surface 12 and another point.
The problem is illustrated graphically in FIG. 7, wherein the vertical axis 50 plots the normalized intensity of light emitted from the front surface 12. The horizontal axis 52 plots the position (that the intensity is measured at) along the sectional line 2--2 (FIG. 1). Point 54 on horizontal axis 52 indicates the position of the left-most light source 24, point 56 indicates the position of the right most light source 26, and point 58 is a position equidistant between the two light sources. The graph is normalized, such that the intensity of position 54 and 56 is 1.0 (both sources are assumed to be of equal intensity).
The curve indicated by dotted line 60 represents the graph of a thin prior art light guide showing its distribution of light intensity across the width of the light guide. Specifically, the dip at point 62, being 70% below the intensity at points 64 and 66, is unacceptable to the average viewer. Curve 60, also illustrates another disadvantage associated with thin prior art light guides, the problem of "hot spots". Hot spots are indicated at points 68 and 70 on curve 60 and are characterized graphically as peaks in the curve.
Generally, prior art light guides are characterized by light transmission inefficiency. To compensate for this, incadescent lamps are used as light sources because they emit more intense light than other light sources of equivalent physical size. The use of the higher intensity incadescent lamps, however, requires additional power consumption, a disadvantage in electronic equipment generally, but a particular difficulty in battery operated equipment where power consumption is critical.
Furthermore, when using liquid crystal displays special problems arise when attempting to view the display outdoors at dusk or dawn. At these times, atmospheric conditions cause a shift in the ambient solar light spectrum towards the red. Because of the disportionately greater amount of red light in the atmosphere at these times, it would be advantageous to have a light source that had a spectral output at a wavelength considerably shorter than that of red light. Incadescent bulbs, with their characteristic white light output, are therefore not well suited for dusk or dawn visibility. Filtering an incadescent bulb would not provide a solution, because filtering merely selectively eliminates a large portion of the visible light spectrum, instead of increasing the intensity of light at the desired wavelength.


A receiver circuit relies on sample data techniques to filter input data signals having a frequency less than a preselected maximum and greater than a preselected minimum. The circuit also rejects a single sine wave cycle. If an input pulse greater than a preselected maximum termination pulse width is encountered during data reception, then reception activity is terminated.

1. Field of the Invention
The present invention relates to integrated circuits utilizable for recovering incoming digital data and, in particular, to a receiver squelch circuit that utilizes sample data techniques for pulse-width filtering.
2. Discussion of the Prior Art
The IEEE 802.3 standard for 10BASE-T Ethernet networks specifies a receiver filtering requirement for incoming data signals. According to the standard, the receiver must reject all signals that are not within the 2-15 MHz frequency range as well as all sine waves of single cycle duration. In addition, the receiver must be capable of recognizing the 250 ns Ethernet active-to-idle transition pulse as an End-of-Packet (EOP) symbol, thereby terminating reception.
Conventional bandpass filters are not suitable for 10BASE-T receiver applications because they do not reject single cycle data nor are they sensitive to the EOP pulse. In addition, bandpass filters are not amplitude-sensitive.
Therefore, it is necessary that a new receiver circuit be provided to meet 802.3 10BASE-T Ethernet requirements.
U.S. Pat. No. 5,285,481, referenced above, discloses a receiver circuit that utilizes analog pulse width timer/integrators to filter data signals having a frequency less than a preselected maximum and greater than a preselected minimum. The circuit also rejects a single sine wave cycle. If an input pulse greater than a preselected maximum pulse width, e.g. the 10BASE-T EOP pulse width, is encountered during data reception, then reception activity is terminated.
While the receiver squelch circuit disclosed in the U.S. Pat. No. 5,285,481 provides a simple, yet elegant solution for meeting the 10BASE-T receiver filter requirement, it is a full analog solution, which, although utilizable in CMOS/BiCMOS receivers, would be much simpler to incorporate in such receivers if implemented in CMOS.
It would, therefore, be highly desireable to have available a CMOS implementation that meets the IEEE 802.3 10BASE-T Ethernet receiver filter standard.

Method and apparatus for sample-data receiver squelch


A light transmitting apparatus of the present invention has cylindrical ducts in which the light transmits, the ducts having an internal light reflection effect and a bending portion having an internal light reflection effect, a cross section of the bending portion is elliptical; wherein the bending portion connects the ducts. Accordingly, the present invention can improve the light transmitting efficiency of the bending part of the apparatus for transmitting the light.

1. Field of the Invention
A present invention relates to a light transmitting apparatus having a bending part, which is used in transmitting, natural light artificial light or the like.
2. Description of the Conventional Art
A light transmitting device has been known in which the light is transmitted inside cylindrical duct so that the light is reflected in the inside of the duct. In a light transmitting apparatus, a straight and cylindrical duct is used to transmit the light linearly. However, a bending part is necessary to transmit the light to a predetermined place.
For example, the conventional light transmitting apparatus has cylindrical ducts. 1, 1' and a bending part 10 as shown in FIG. 2A. The cross section of the bending part is shown in FIG. 2D. As shown in FIGS. 2B and 2C, the conventional light transmitting has a duct 1, 1'. The bending part 10 includes a flat reflecting mirror 2 inclined at 45.degree. to obtain a regular reflection effect with respect to the light transmission direction, triangular side reflecting mirrors 3 mounted at both sides of the flat reflecting mirror 2 so as to transmit the light in the perpendicular direction, and coupling members 5, 5' which are respectively connected with the ducts 1, 1' so as to connect the bending part 10 with the ducts 1, 1'. Consequently, the light transmitted in the duct 1 can be introduced into the duct 1' which is perpendicular to the duct 1.
However, the shape of a light distribution of an outgoing light which is transmitted in the duct 1 having the reflection effect depends on the shape of a light distribution of a incoming light, but generally, is axially symmetrical along the light transmission direction. Some part of the axially symmetrical light which is reflected by the center portion of the flat reflecting mirror 2 being set at an angle so as to perform a regular reflection is effectively reflected to a desirable direction as a primary reflected light. However, since the number of reflections of the light reflected by the side flat reflecting mirrors 3 is two or more, the light reflected by the side flat reflecting mirrors 3 cannot be reflected effectively. Such a problem has been an obstruction in light transmission.
In addition, for example, the other conventional light transmitting apparatus has the duct 1, 1' and a bending part 6 having a circular cross section as shown in FIGS. 3A and 3B. The transmitting efficiency of this light transmitting apparatus is better than the former conventional light transmitting apparatus. However, this light transmitting device also has a problem in the transmitting efficiency.