Compositions for dyeing keratin fibers comprise (a) at least one keratin dyeing compound selected from aromatic systems which comprise at least one boronic acid or boronic ester moiety and which are capable of forming upon oxidation a nucleophile or an electrophile, (b) at least one additional keratin dyeing compound selected from the group consisting of auxiliary developers and auxiliary couplers, and (c) a cosmetically suitable medium. Methods for oxidatively dyeing keratin fibers comprise the steps of applying such compositions in the presence of an oxidizing agent and rinsing the hair. A hair coloring product in kit form comprises a first separately packaged container comprising a composition as described above and a second separately packaged container comprising an oxidizing agent.

The most extensively used method currently employed to dye keratin fibers, such as hair, is by an oxidative process that utilizes one or more oxidative dye compounds in combination with one or more oxidizing agents.
Commonly, a peroxy oxidizing agent is used in combination with one or more developers or couplers, which are generally small molecules capable of diffusing into hair. A wide variety of oxidants may be used to generate the reactive developer species. Generally, a peroxide material, such as hydrogen peroxide, activates the developers so that they react with the couplers to form larger sized compounds in the hair shaft to give a variety of shades and colors.
A wide variety of developers and couplers have been employed in such oxidative hair coloring systems and compositions. However, there still exists a need for additional keratin dyeing compounds which can act as developers and/or couplers and which can safely provide color benefits.
Hydrogen peroxide-mediated transformation of arylboronic acids or arylboronic esters to phenols has been investigated to develop highly selective and sensitive probes for hydrogen peroxide, which is one of the major reactive oxygen species ("ROS") in living cells. The kinetics of the reaction between hydrogen peroxide and phenylboronic acid was investigated by Henry G. Kuivila et al., J. Am. Chem. Soc. 1957, 79, 5659, who proposed the following mechanism:

Additionally, the transformation of boronic acids and boronic esters to the corresponding alcohols by the use of Oxone™ in aqueous acetone buffered with sodium bicarbonate has been described by Kevin S. Webb et al., Tetrahedron Letters, 1995, 36, 5117.
More recently, the syntheses and biological applications of fluorescent probes for hydrogen peroxide have been reported by Michelle C. Y. Chang et al., J. Am Chem. Soc., 2004, 126, 15392 and 2005, 127, 16652. These peroxysensors utilize a boronate-hydrogen peroxide reaction to provide high selectivity for detecting hydrogen peroxide in aqueous solution. The boronate compound is non-fluorescent and displays no absorption in the visible region. The addition of hydrogen peroxide triggers immediate increase in fluorescence and growth of visible wavelength absorption bands characteristic fluorescein and red-fluorescent resorufin, as shown in the following mechanisms, respectively:

The aforementioned references, however, do not disclose the use of such boronic acid and boronic ester compounds in compositions for oxidatively dyeing keratin fibers.
It has now been discovered that certain aromatic systems comprising at least one boronic acid or boronic ester moiety are capable of imparting commercially desirable colors to keratin fibers, such as hair. Such boronic acid or boronic ester compounds are capable of providing dyeing results comparable, in terms of color and intensity, to those achieved by using known oxidative dye compounds. Accordingly, there exists a need for keratin fiber dyeing compositions which comprise aromatic systems comprising at least one boronic acid or boronic ester moiety.

Compositions for oxidatively dyeing keratin fibers and methods for using such compositions


The present disclosure discloses a suspension insulator and a suspension insulator group. The suspension insulator comprises a silicone rubber umbrella string and a fiber-reinforced resin-based composite rod, wherein the silicone rubber umbrella string is arranged on the fiber-reinforced resin-based composite rod. Since the umbrella string is made of silicone rubber and is arranged on the fiber-reinforced resin-based composite rod, as compared with porcelain suspension insulator or glass suspension insulator, it has a low density and a light weight, and may reduce the load of the tower and is convenient to install and remove. The suspension insulator provided by the present disclosure is especially applicable to the field of power transmission.

Power grids have developed rapidly around the world with the development of economy. There has been an increasing demand for various components used in the power grids, and insulators are among the rest. Insulators are used to support transmission lines, and may ensure sufficient insulation between the transmission lines and the crossarm and the tower. In operation, the insulators should be capable of withstanding the vertical load and the horizontal tension of the transmission lines. The insulators are also exposed to the sun and rain, and are subject to the change of weather and corrosion of chemicals. Therefore, the insulators are required to have both excellent electrical performances and sufficient mechanical strength. The quality of insulators is critical to the safe operation of the transmission lines.
Insulators can be classified by structure as supporting insulator, suspension insulator, anti-pollution insulator and bushing insulator. Commonly used in overhead lines are pin insulator, shackle insulator, suspension insulator, porcelain crossarm, rod insulator, strain insulator, etc. Electrical faults of insulators include flashover and breakdown. Flashover occurs in the surface of the insulator, with visible burn marks but normally without damaging the insulation; breakdown occurs in the interior of the insulator by discharging through the porcelain between an insulator cap and an insulator pin, possibly damaging the insulation but without any marks in the appearance, and also possibly destroying the insulator completely due to an electric arc. For breakdown, the insulator pin should be examined for the discharging mark and the burn mark.
Currently, disk-type multi-piece suspension insulators are often used, as shown in FIG. 1. FIG. 2 illustrates one single piece of FIG. 1. As shown in FIG. 2, the single piece comprises a socket 1, an umbrella 11 and a head 9. A plurality of (e.g., n in FIG. 1) single-pieces are connected in series to form the structure in FIG. 1. Conventional suspension insulators are made of porcelain or glass, and especially, porcelain insulators have existed for more than 100 years. However, porcelain or glass has a high density, which imposes a heavy load to the tower.

Suspension insulator and suspension insulator group

Zibo Taiguang Electric Power Equipment Factory


A method, system, and computer program product for mitigating adjacent track erasures in hard disks, includes: determining input/output (I/O) characteristics for a plurality of blocks on a hard disk; assigning the plurality of blocks to a plurality of categories of I/O characteristics by the processor; and clustering content of the blocks assigned to the same category in one or more continuous tracks on the hard disk. Each block is assigned to one category. Blocks with similar I/O characteristics are clustered on one or more continuous tracks. By performing this clustering, blocks with a high number of I/O operations are grouped and stored on fewer tracks than if they were scattered across numerous tracks. This reduces the number of tracks experiencing a high number of I/O operations, and in turn, the amount of refreshing of adjacent tracks is reduced.

Secure deletion of data on non-volatile magnetic data storage, such as a hard disk, is an act of securely purging the data such that there are no residuals of the data on the hard disk. Regulations exist which mandate the need for secure deletion according to various standards, such as that published by the U.S. Department of Defense. A hard disk drive includes one or more hard disks clamped to a rotating spindle and at least one head for reading or writing data on the disk. Storage on a hard disk is divided into "blocks", which are in turn grouped into "tracks". A disk head uses magnetism to read or write data onto the tracks. Secure deletion involves the overwriting of blocks on a track by the disk head numerous times, depending on the standard being applied. Thus, secure deletion involves multiple input/output (I/O) operations on the same blocks of a track.
As a track on the hard disk is written, adjacent tracks may be overwritten by the magnetic field generated in the disk head, and data recorded in the adjacent tracks may be erased or corrupted as a result. This phenomenon is called adjacent track erasure (ATE) or adjacent track interference (ATI) and are aggravated by the multiple overwrites required by secure deletion.
In one approach to counter ATE or ATI, when a track has been overwritten a certain number of times, the adjacent tracks are read and rewritten, hence refreshing the data on the adjacent tracks. However, the I/O operations required in the refreshing of the adjacent tracks impose a performance penalty on the hard disk drive. With the aggravation of the ATE and ATI phenomenon due to secure deletion requirements, the need to refresh adjacent tracks become more frequent, imposing an even high performance penalty on the hard disk drive.

Method and system for mitigating adjacent track erasure in hard disk drives

International Business Machines Corporation


A method for detecting a relevant region in the surroundings of an ego vehicle, in which a situation exists which is relevant to the driving and/or safety of the ego vehicle, from measurement data of a sensor which observes at least a portion of the surroundings, the measurement data being discretized into pixels or voxels and/or are suitably represented in some other way, the existence of the relevant situation being dependent on the presence of at least one characteristic object in the surroundings, and the resolution of the pixels, voxels and/or the other representation being insufficient for directly detecting the characteristic object, the measurement data being analyzed for the presence of a grouping of objects which contains the characteristic object, the resolution of the pixels, voxels and/or the other representation being sufficient for detecting the grouping. A region in which the grouping is detected is classified as a relevant region.

Depending on the situation, driving a vehicle in traffic requires the acquisition of information from areas surrounding the vehicle, which are located at greatly varying distances from the vehicle. When turning right, for example, it is necessary to look over the shoulder in order to check whether there is another road user wishing to travel straight ahead who is located immediately to the right next to the host vehicle, in the "blind spot" of the mirrors. In fast-moving traffic on expressways or on rural roads, on the other hand, it is necessary to look very far ahead so as to be able to react in good time to any driving-relevant situations. For instance, at a speed of 200 km/h, the stopping distance according to the rule of thumb is more than 450 m. A tail end of a traffic jam for example must be detected at this distance in order to avoid a collision.
An attentive human driver may look both at close range and into the distance using one and the same pair of eyes as sensors. Technological sensors used for this purpose are typically specialized for particular distance ranges. For instance, European Patent No. EP 2 084 045 B1 describes combining multiple sensors which have different detection ranges and bridging the intermediate ranges by using a transfer algorithm. Further general related art regarding object detection is described in U.S. Patent Application Publication No. US 2016/371 549 A1 and in German Patent Application No. DE 10 2015 205 135 A1.

Detecting driving-relevant situations at a larger distance


An audio system (e.g., of an artificial reality headset) determines a position of the headset relative to a position of a head of a user wearing the headset. The determination is based in part on an image of a portion of the head from a tracking camera (e.g., eye tracking and/or face tracking) on the headset. The audio system adjusts an acoustic parameter based in part on the determined position of the headset. The audio system performs an action that uses the adjusted acoustic parameter.

Augmented reality glasses often are mounted on a frame, and effectiveness of the glasses is dependent on their position and orientation on a head. Techniques such as visual inertial odometry can be used to track the device-centric, world-locked position and orientation for glasses. However, it is generally difficult to assess the position and orientation of glasses relative to a wearer's head. Moreover, there is a person-to-person and fit-to-fit variation of glasses to heads of different users. This can result in reduced sensor performance on the glasses as well as inconsistent audio performance (e.g., caused by movement of the glasses on the head of the wearer).

Adjusting acoustic parameters based on headset position


A double-walled pipe with integrated heating capability for an aircraft or spacecraft includes a pipe body rigidly formed from plastic in one piece with an inner wall, with an outer wall and with a plurality of wall supports, the wall supports connecting the inner wall to the outer wall, the inner wall and the outer wall defining an intermediate space. The double-walled pipe further includes an electrically conductive coating surrounding the inner wall within the intermediate space and configured to heat up under application of an electric current such that heat is transferred to the inner wall.

The present invention pertains to a double-walled pipe with integrated heating capability for an aircraft or spacecraft and a method for manufacturing a double-walled pipe of this type.
Although applicable to various pipe systems for any kind of aircraft or spacecraft or the like, the present invention and the problem on which it is based will be explained in greater detail with reference to water pipes of commercial aircraft. In principle, however, the present invention may also be utilized in other pipe systems that are configured for transportation of various fluids like oil, fuel, water or the like. Further, the present invention may be used in various parts of aircraft, like, for example, aircrafts floors, wings, cargo bays, etc., in particular, in the context of ice protection applications.
In contemporary commercial aircraft a plurality of water pipes are used for applications like waste water transportation, cargo drainage, or humidifier piping. These pipes are often formed from stainless steel or titanium and are connected by welded elbows and T-pieces or similar elements. However, the temperature of the air around aircraft may drop significantly below the freezing point during operation in high altitudes. In order to prevent water pipes from freezing during flight, water conduits are typically heated and/or drained of any fluid. Heating may, for example, be provided by a linear tape heater. In this case, a linear electrical heating tape may be attached to one side of the pipes. In addition, the heater and/or the pipes may be surrounded by electrical and/or thermal insulation means. In order to transfer heat from a heater to the pipe walls more efficiently, a heating layer may be provided that fully surrounds the outer surface of the pipes. In this case, the entire pipe surface may be heated and power consumption may be reduced.
Document DE 10 2010 010 929 A1 discloses, for example, a self-heating water conduit segment made from metal with an integrated heating device. The heating device is a semiconductor heating device comprising an inner conductor being surrounded by a semiconductor layer, which in turn is surrounded by an outer conductor. The inner conductor hereby serves as an inner pipe for water transportation.
Document DE 20 2005 004 602 U1 discloses a heated flexible plastic hose that includes an extruded inner plastic sleeve surrounded by a layer of a conductive polymer with a positive temperature coefficient (PTC) for heating of the inner sleeve. The conductive layer itself is surrounded by an outer plastic sleeve that is sprayed on the conductive layer.
In general, any weight reduction per pipe can have significant impact on aircraft load and, in consequence, fuel consumption. In addition, it is desirable to provide a means of heating that is as uniform and efficient as possible with minimal installation and/or production effort. 3D printing provides extraordinary design freedom and hence it is widely used for manufacturing with multiple applications in engineering, construction, industrial design, automotive industries, and aerospace industries. Amongst various advantages, it offers the possibility to manufacture complex hollow rigid structures in one piece that are much more cumbersome to produce with conventional manufacturing methods. Conventional methods often do not allow to produce hollow objects in an integral way at all, but require to assemble these from a number of individual subcomponents.

Double-walled pipe with integrated heating capability for an aircraft or spacecraft


Polymeric adhesive comprising a homogeneous mixture of at least three constituents: (a) at least one thermoplastic halogenated hydrocarbon polymer, (b) at least one copolymer of monoethylenic monomers which carry an alkyl carboxylate functional group and (c) at least one alpha-olefin polymer modified by the incorporation of at least one functional group chosen from a carboxyl, an acid anhydride, a hydroxyl and an epoxide. Process for the preparation of this polymeric adhesive and use of this polymeric adhesive in the preparation of structures with multiple polymeric layers.

The present invention relates to a polymeric adhesive and to structures with multiple polymeric layers comprising a layer (A) made of thermoplastic halogenated hydrocarbon polymer bonded to a layer (C) made of thermoplastic non-halogenated polymer incompatible with (A) via a layer (B) based on a polymeric adhesive. The invention also relates to processes for the preparation of this adhesive and of these structures. The invention additionally relates to the use of this adhesive in the preparation of these structures and to the use of these structures in the manufacture of pipes, tubes, films, sheets, panels and hollow bodies.
Thermoplastic halogenated hydrocarbon polymers and more particularly thermoplastic fluorinated hydrocarbon polymers are polymers which exhibit an array of advantageous properties and in particular impermeability to liquids and gases, high chemical inertia and excellent behaviour towards ageing. For this reason, they have multiple applications in highly diverse fields and in particular in the transportation and storage of liquids and gases and in protection against corrosion. Nevertheless, they exhibit the disadvantage of being relatively expensive, with the risk of their outlets being restricted.
An appropriate means for reducing the cost of shaped articles made of this type of polymer consists in using these polymers in the form of structures with multiple polymeric layers (films, sheets, panels, pipes, hollow bodies, and the like) in which they are used in combination with other polymers, which furthermore contribute their own properties and advantages, such as, for example, mechanical strength, aptitude for sealing, resistance to scratching, and the like. However, thermoplastic halogenated hydrocarbon polymers and more particularly thermoplastic fluorinated hydrocarbon polymers are known to be materials which cannot easily be made to adhere to other polymers.
To solve this problem, numerous solutions have been provided and in particular to insert a layer of adhesive between the halogenated polymer and the incompatible polymer, in order to provide an adhesive bond between these two polymers.
This type of solution has been disclosed in particular in Patent Applications EP-A1-112,406, EP-A1-124,931 and EP-A1-484,053.
Thus, Patent Application EP-A1-112,406 relates to a multilayer hollow container composed of an internal layer made of thermoplastic fluorocarbon-comprising resin bonded to an external layer made of polyolefin via a layer made of a mixture of resins comprising a polyolefin grafted with an unsaturated glycidyl compound and a polyolefin.
Likewise, Patent Application EP-A1-124,931 discloses multiple-layer thermoplastic structures comprising a layer made of vinyl or vinylidene fluoride polymer bonded to a layer made of alpha-olefin polymer with the joint involvement of a vinyl acetate polymer and of a copolymer of ethylene and of vinyl acetate.
Patent Application EP-A1-484,053 mentions a process for the preparation of a 3-layer laminate composed of a layer of an olefinic polymer to which a layer of fluorinated resin is made to adhere by melting with the aid of an adhesive polymer which consists of a polymerization product of an olefinic polymer with a monomer comprising an alkyl (meth)acrylate and/or an unsaturated monomer comprising fluorine.
These types of adhesive layers provided as solutions in these specific cases do not, however, comprise a mixture of the two polymers which are to be made to adhere and for this reason exhibit adhesive properties which might be improved.
Provision has also been made to make a halogenated polymer, in this instance a fluorinated polymer, adhere to an incompatible polymer via two distinct layers of adhesive.
Thus, Patent EP-B1-206,689 relates to a laminate comprising at least two distinct layers of adhesive in contact, composed of a fluorinated hydrocarbon polymer modified by a carboxyl, acid anhydride, hydroxyl or epoxide group and of an alpha-olefin polymer modified by a carboxyl, acid anhydride, hydroxyl or epoxide group different from the preceding group. These two distinct layers of adhesive can be placed on a substrate layer prepared from a material chosen from various polymers, including poly(vinylidene fluoride), polyethylene and nylon. Thus, a 4-layer laminate is mentioned comprising a PVDF layer bonded to a PE layer via two distinct layers of adhesive. This multilayer structure exhibits the disadvantage of being composed of two layers of adhesive and thus a total of 4 layers, which presents technical problems during the industrial coextrusion, which can be more easily envisaged technically if it is limited to 3 layers, thus with a single layer of adhesive.
Due to their lower cost and to the technical considerations with regard to manufacture described above, structures having a single layer of adhesive are preferred to those comprising more than one layer of adhesive.
The problem which remains is therefore that of providing an adhesive which can satisfactorily bond to a layer of thermoplastic halogenated hydrocarbon polymer, on one side, and to a layer of incompatible thermoplastic polymer, on the other side, for the purpose of forming structures with multiple polymeric layers comprising only a single layer of adhesive.
In order to overcome the abovementioned disadvantage, the object of the present invention is to provide a homogeneous polymeric adhesive which comprises a mixture of the two polymers to be made to adhere and which thus makes it possible to provide good adhesion between a thermoplastic halogenated hydrocarbon polymer and an incompatible thermoplastic polymer.
Another subject-matter of the invention is, a process for the preparation of this adhesive and the use of this adhesive in the preparation of structures with multiple polymeric layers.
Another object of the invention is to provide structures with multiple polymeric layers comprising a layer (A) made of thermoplastic halogenated hydrocarbon polymer bonded to a layer (C) made of incompatible thermoplastic nonhalogenated polymer via a single layer (B) based on a homogeneous polymeric adhesive which makes it possible for these structures to combine good adhesion with good barrier properties and with a not excessively high cost, to be easily coextruded industrially and not to exhibit, for this reason, the abovementioned disadvantage.
Another subject-matter of the invention is a process for the preparation of these structures with multiple polymeric layers and the use of these structures with multiple polymeric layers in the manufacture of pipes, tubes, films, sheets, panels and hollow bodies.
The invention first of all relates to a polymeric adhesive which is particularly suitable for providing good adhesion between a thermoplastic halogenated hydrocarbon polymer and an incompatible thermoplastic polymer.
To this end, the invention relates to a polymeric adhesive which comprises a homogeneous mixture of at least three components: (a) at least one thermoplastic halogenated hydrocarbon polymer, (b) at least one copolymer of monoethylenic monomers which carry an alkyl carboxylate functional group and (c) at least one alpha-olefin polymer modified by the incorporation of at least one functional group chosen from a carboxyl, an acid anhydride, a hydroxyl and an epoxide.
The term xe2x80x9cthermoplastic halogenated hydrocarbon polymerxe2x80x9d is understood to denote homopolymers and copolymers obtained from monoethylenic monomers comprising at least two carbon atoms and at least one halogen atom chosen from fluorine and chlorine. It is also understood to denote mixtures of homopolymers and of copolymers. Mention may in particular be made, as examples of thermoplastic halogenated hydrocarbon polymer which can be used in the present invention, of homopolymers and copolymers of vinylidene fluoride, of vinyl fluoride, of trifluoroethylene, of chlorotrifluoroethylene, of tetrafluoroethylene, of hexafluoropropylene, of vinyl chloride and of vinylidene chloride, as well as copolymers of one of these monomers with another nonhalogenated monoethylenic monomer, such as ethylene, vinyl acetate and acrylic or methacrylic monomers.
The thermoplastic halogenated hydrocarbon polymer (a) is preferably a thermoplastic fluorinated hydrocarbon polymer. In a most preferred way, the thermoplastic halogenated hydrocarbon polymer (a) is a vinylidene fluoride polymer.
The term xe2x80x9cthermoplastic fluorinated hydrocarbon polymerxe2x80x9d is understood to denote homopolymers and copolymers obtained from monoethylenic monomers comprising at least two carbon atoms and at least one fluorine atom. The monoethylenic monomers can additionally comprise one or more chlorine atoms in addition to the fluorine atoms. The term is also understood to denote mixtures of homopolymers and of copolymers. Mention may in particular be made, as examples of thermoplastic fluorinated hydrocarbon polymer which can be used in the present invention, of homopolymers and copolymers of vinylidene fluoride, of vinyl fluoride, of trifluoroethylene, of chlorotrifluoroethylene, of tetrafluoroethylene and hexafluoropropylene, as well as copolymers of one of these monomers with another nonhalogenated monoethylenic monomer, such as ethylene, vinyl acetate and acrylic or methacrylic monomers. Vinylidene fluoride polymers are preferred.
The term xe2x80x9cvinylidene fluoride polymerxe2x80x9d is understood to denote, for the purposes of the present invention, any polymer comprising at least approximately 75% by weight of monomer units derived from vinylidene fluoride. Vinylidene fluoride polymers which may be suitable for producing structures with multiple polymeric layers according to the invention therefore comprise both vinylidene fluoride homopolymers and copolymers of vinylidene fluoride comprising monomer units derived from one or more ethylenically unsaturated comonomers which are advantageously fluorinated, as well as mixtures of these polymers. Mention may be made, by way of example of fluorinated comonomers which can be used, of vinyl fluoride, trifluoroethylene, chlorotrifluoroethylene, tetrafluoroethylene and hexafluoropropylene.
The copolymer of monoethylenic monomers which carry an alkyl carboxylate functional group (b) which can be used for the purposes of the present invention is a copolymer of at least two monoethylenic monomers which carry an alkyl carboxylate functional group.
Preference is given, among monoethylenic monomers carrying an alkyl carboxylate functional group which can be used for the implementation of the present invention, to alkyl carboxylates which can be obtained by the reaction of a monoethylenic carboxylic acid comprising a total of at least 3 carbon atoms, preferably at least 5 carbon atoms, alternatively at least 8 carbon atoms, with an alcohol chosen from linear or branched alcohols comprising at least 1 carbon atom and at most 20 carbon atoms, such as, for example, methanol, ethanol, isopropanol, n-butanol, isobutanol, t-butanol, hexanol, n-octanol, 2-ethylhexanol, decanol, isodecanol, lauryl alcohol, hexadecanol and octadecanol, but also glycidol, cyclohexanol and benzyl alcohol. Among these alcohols, those comprising from 1 to 10 carbon atoms are preferred. Methanol and glycidol are very particularly preferred. Methyl and glycidyl acrylates and methacrylates are the preferred monoethylenic monomers carrying an alkyl carboxylate functional group. Methyl and glycidyl methacrylates are very particularly preferred.
Preference is given, among monoethylenic monomers carrying an alkyl carboxylate functional group which can be used for the implementation of the present invention, to alkyl carboxylates which can be obtained by the reaction of a monoethylenic carboxylic acid comprising a total of at most 8 carbon atoms, preferably at most 5 carbon atoms, alternatively at most 3 carbon atoms, with an alcohol chosen from linear or branched alcohols comprising at least 1 carbon atom and at most 20 carbon atoms, such as, for example, methanol, ethanol, isopropanol, n-butanol, isobutanol, t-butanol, hexanol, n-octanol, 2-ethylhexanol, decanol, isodecanol, lauryl alcohol, hexadecanol and octadecanol, but also glycidol, cyclohexanol and benzyl alcohol. Among these alcohols, those comprising from 1 to 10 carbon atoms are preferred. Methanol and glycidol are very particularly preferred. Methyl and glycidyl acrylates and methacrylates are the preferred monoethylenic monomers carrying an alkyl carboxylate functional group. Methyl and glycidyl methacrylates are very particularly preferred.
The copolymer (b) is preferably a copolymer of two monoethylenic monomers which carry an alkyl carboxylate functional group, it being possible for each of them to be obtained by the reaction of a monoethylenic monomer carrying a carboxylic acid functional group comprising a total of 3 to 8 carbon atoms with a linear or branched alcohol comprising from 1 to 20 carbon atoms.
In a most preferred way, the copolymer (b) is a copolymer of two monoethylenic monomers which carry an alkyl carboxylate functional group, it being possible for each of them to be obtained by the reaction of a monoethylenic monomer carrying a carboxylic acid functional group comprising a total of 3 to 5 carbon atoms with a linear or branched alcohol comprising from 1 to 10 carbon atoms.
The very particularly preferred copolymer (b) is a copolymer of methyl methacrylate and of glycidyl methacrylate.
The copolymer (b) used for the purposes of the present invention can comprise at least from 5 to 95% by weight, with respect to the total weight of the monomers, of the first monoethylenic monomer carrying a carboxylate functional group and at least from 95 to 5% by weight, with respect to the total weight of the monomers, of the second monoethylenic monomer carrying a carboxylate functional group.
The copolymer (b) preferably comprises approximately 50% by weight, with respect to the total weight of the monomers, of each of the monoethylenic monomers carrying an alkyl carboxylate functional group.
The copolymer (b) used for the purposes of the present invention can also comprise amounts of less than or equal to 5% by weight, with respect to the total weight of the monomers, of other monomers which are copolymerizable with the monoethylenic monomers carrying a carboxylate functional group. Mention may be made, by way of examples, of acrylic acid and methacrylic acid.
The modified alpha-olefin polymer (c) which can be used for the purposes of the present invention is a polymer which can be prepared from a homopolymer or from a copolymer of an alpha-olefin. Preferred examples of alpha-olefin polymers comprise polyethylene, polypropylene, an ethylene/propylene copolymer, an ethylene/1-butene copolymer, an ethylene/4-methyl-1-pentene copolymer, a propylene/1-butene copolymer, poly(1-butene) and copolymers of the abovementioned alpha-olefins with minor amounts of diolefins or of unsaturated carboxylic acid esters, such as an ethylene/butadiene copolymer, a propylene/butadiene copolymer, an ethylene/vinyl acetate copolymer and an ethylene/ethyl acrylate copolymer.
In order to prepare a modified alpha-olefin polymer, at least one functional group chosen from a carboxyl, an acid anhydride, hydroxyl and an epoxide can be incorporated in one of the alpha-olefin polymers defined above or in a composition of these polymers. The functional group can be introduced into the alpha-olefin polymer by a series of methods, such as a method in which a polymerizable monomer carrying the functional group is incorporated in the alpha-olefin polymer by statistical or block copolymerization or by grafting, a method in which the reactive group of the alpha-olefin polymer reacts with a compound carrying the functional group or a group which can form the functional group by reaction, and a method in which the alpha-olefin polymer is modified by oxidation, hydrolysis or any other appropriate method. The first and the third methods are preferred because they make it possible to easily introduce, and in a controlled amount, the functional group into the alpha-olefin polymer. Copolymerization by grafting is particularly preferred for two reasons: a low amount of functional group is sufficient to improve the adhesion and the modified polymer does not undergo an excessively great deterioration in its physical properties.
Examples of monomers carrying a carboxyl or acid anhydride group are acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, citraconic acid, maleic anhydride, itaconic anhydride, crotonic anhydride and citraconic anhydride. Acrylic acid and maleic anhydride are preferred with the aim of improving the adhesion. Maleic anhydride is very particularly preferred.
A hydroxyl group can be introduced by hydrolysis of a copolymer of a vinyl ester, such as vinyl acetate or vinyl propionate, or by copolymerization of an unsaturated alcohol, such as a dihydric alcohol, with an acrylic or methacrylic acid ester.
Examples of monomers carrying a hydroxyl group are 2-hydroxyethyl acrylate and methacrylate, 2-hydroxypropyl acrylate and methacrylate, 2-hydroxybutyl acrylate and methacrylate, N-(methylol)acrylamide and N(methylol)methacrylamide, 2-propyn-1-ol and hydroxy vinyl ethers.
Examples of monomers carrying an epoxide group are glycidyl acrylate, glycidyl methacrylate, glycidyl ethylacrylate, mono- and diglycidyl itaconate, mono- and diglycidyl maleate, mono- and diglycidyl allylsuccinate, allyl glycidyl ether, 2-methylallyl glycidyl ether, p-glycidylstyrene, 3,4-epoxy-1-butene, 3,4-epoxy-3-methyl-1-butene and vinylcyclohexene monoxide.
The modified alpha-olefin polymer (c) which is very particularly preferred is polyethylene grafted with maleic anhydride.
The modified alpha-olefin polymer can comprise at least 0.1% by weight of functional group. The modified alpha-olefin polymer can comprise at least 0.5%, at least 1%, at least 10%, at least 20% or at least 30% by weight of functional group.
The modified alpha-olefin polymer can alternatively comprise at most 30% by weight of functional group. The modified alpha-olefin polymer can comprise at most 20%, at most 10%, at most 1%, at most 0.5% or at most 0.1% by weight of functional group.
For the purpose of obtaining good peel strengths, it is preferable for the modified alpha-olefin polymer to comprise at least 0.1% by weight of functional group. The modified alpha-olefin polymer preferably comprises at least 0.5% by weight of functional group. In a very particularly preferred way, the modified alpha-olefin polymer comprises at least 1% by weight of functional group.
For the purpose of obtaining an improved aptitude for moulding and improved physical properties (such as, for example, a good balance between impact strength and stiffness), it is preferable for the modified alpha-olefin polymer to comprise at most 30% by weight of functional group. The modified alpha-olefin polymer preferably comprises at most 20% by weight of functional group. In a very particularly preferred way, the modified alpha-olefin polymer comprises at most 10% by weight of functional group.
The thermoplastic halogenated hydrocarbon polymer (a) is present in the homogeneous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at least 20%, of at least 25%, of at least 30%, of at least 72%, of at least 77% or of at least 80%.
The thermoplastic halogenated hydrocarbon polymer (a) is alternatively present in the homogeneous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at most 80%, of at most 77%, of at most 72%, of at most 30%, of at most 25% or of at most 20%.
The thermoplastic halogenated hydrocarbon polymer (a) is preferably present in the homogeneous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at least 25%. In a very particularly preferred way, the thermoplastic halogenated hydrocarbon polymer (a) is present in the homogeneous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at least 30%.
The thermoplastic halogenated hydrocarbon polymer (a) is preferably present in the homogeneous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at most 77%. In a very particularly preferred way, the thermoplastic halogenated hydrocarbon polymer (a) is present in the homogeneous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at most 72%.
The copolymer of monoethylenic monomers which carry an alkyl carboxylate functional group (b) is present in the homogeneous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at least 36%, of at least 5%, of at least 7%, of at least 30%, of at least 35% or of at least 40%.
The copolymer of monoethylenic monomers which carry an alkyl carboxylate functional group (b) is alternatively present in the homogeneous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at most 40%, of at most 35%, of at most 30%, of at most 7%, of at most 5% or of at most 3%.
The copolymer of monoethylenic monomers which carry an alkyl carboxylate functional group (b) is preferably present in the homogeneous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at least 5%. In a very particularly preferred way, the copolymer of monoethylenic monomers which carry an alkyl carboxylate functional group (b) is present in the homogenous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at least 7%.
The copolymer of monoethylenic monomers which carry an alkyl carboxylate functional group (b) is preferably present in the homogeneous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at most 35%. In a very particularly preferred way, the copolymer of monoethylenic monomers which carry an alkyl carboxylate functional group (b) is present in the homogeneous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at most 30%.
The alpha-olefin polymer modified by the incorporation of at least one functional group chosen from a carboxyl, an acid anhydride, a hydroxyl and an epoxide (c) is present in the homogeneous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at least 15%, of at least 17%, of at least 20%, of at least 45%, of at least 50% or of at least 55%.
The alpha-olefin polymer modified by the incorporation of at least one functional group chosen from a carboxyl, an acid anhydride, a hydroxyl and an epoxide (c) is alternatively present in the homogeneous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at most 55%, of at most 50%, of at most 45%, of at most 20%, of at most 17% or of at most 15%.
The alpha-olefin polymer modified by the incorporation of at least one functional group chosen from a carboxyl, an acid anhydride, a hydroxyl and an epoxide (c) is preferably present in the homogeneous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at least 17%. In a very particularly preferred way, the alpha-olefin polymer modified by the incorporation of at least one functional group chosen from a carboxyl, an acid anhydride, a hydroxyl and an epoxide (c) is present in the homogeneous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at least 20%.
The alpha-olefin polymer modified by the incorporation of at least one functional group chosen from a carboxyl, an acid anhydride, a hydroxyl and an epoxide (c) is preferably present in the homogeneous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at most 50%. In a very particularly preferred way, the alpha-olefin polymer modified by the incorporation of at least one functional group chosen from a carboxyl, an acid anhydride, a hydroxyl and an epoxide (c) is present in the homogeneous mixture constituting the polymeric adhesive of the present invention, for a total weight of 100%, in an amount of at most 45%.
The present invention also relates to a process for the preparation of the polymeric adhesive.
The process for the preparation of the polymeric adhesive can be carried out by homogeneous mixing of at least three constituents: (a) at least one thermoplastic halogenated hydrocarbon polymer, (b) at least one copolymer of monoethylenic monomers which carry an alkyl carboxylate functional group and (c) at least one alpha-olefin polymer modified by the incorporation of at least one functional group chosen from a carboxyl, an acid anhydride, a hydroxyl and an epoxide.
The homogeneous mixing of the constituents (a), (b) and (c) of the polymeric adhesive can be carried out according to any known mixing technique, the ingredients being in the solid state or in the molten state. In order to ensure the homogeneity of the mixing and good dispersion of the constituents in the polymeric adhesive, kneading is generally carried out in the temperature region corresponding to the viscoelastic state of the polymers.
The kneading can be carried out by any means known for this purpose. Thus, it is possible to operate without distinction in kneaders of the external type or of internal type. Kneaders of the internal type are preferred and more particularly extruders, which constitute a specific class of internal kneaders. Kneading can be carried out under the usual conditions well known to a person skilled in the art.
It is possible, without distinction, to mix the three constituents together or first to mix two of them, followed by mixing with the third.
The kneading temperature is not critical and is conditioned by the nature and the decomposition temperatures of the ingredients. The operation is generally carried out at temperatures not exceeding 250xc2x0 C. (220xc2x0 C. for polyamides).
The duration of the kneading is chosen by taking into account the nature of the constituent polymers of the mixture and the temperature applied. The duration of the kneading can be at least 5 seconds, at least 10 seconds, at least 15 seconds, at least 10 minutes, at least 15 minutes or at least 20 minutes.
The duration of the kneading can alternatively be at most 20 minutes, at most 15 minutes, at most 10 minutes, at most 15 seconds, at most 10 seconds or at most 5 seconds.
The duration of the kneading is preferably at least 10 seconds. In a most preferred way, the duration of the kneading is at least 15 seconds.
The duration of the kneading is preferably at most 15 minutes. In a most preferred way, the duration of the kneading is at most 10 minutes.
The present invention also relates to the use of the polymeric adhesive according to the invention in the preparation of structures with multiple polymeric layers.
When it is used in structures with multiple polymeric layers according to the invention, this polymeric adhesive constitutes the layer denoted xe2x80x9clayer (B)xe2x80x9d.
Additional constituents in minor amounts can be incorporated in the mixture constituting the layer (B) based on a polymeric adhesive. Mention may be made, by way of examples, of fluorinated elastomers (such as the fluorinated rubber DAI-EL(copyright) G 801), acrylic elastomers (such as methyl methacrylate/butadiene copolymers) and ethylene/propylene, ethylene/1-butene, propylene/1-butene and butadiene/styrene copolymers. The total amount of the additional constituent or constituents advantageously does not exceed 5% by weight with respect to the total weight of the layer (B).
The invention also relates to structures with multiple polymeric layers comprising a layer (A) based on thermoplastic halogenated hydrocarbon polymer bonded to a layer (C) based on thermoplastic nonhalogenated polymer incompatible with (A) via a layer (B) based on a polymeric adhesive as defined above.
The term xe2x80x9cstructures with multiple polymeric layers comprising a layer (A) based on thermoplastic halogenated hydrocarbon polymer bonded to a layer (C) based on thermoplastic nonhalogenated polymer incompatible with (A)xe2x80x9d is understood to denote multilayer structures comprising at least one layer (A) based on thermoplastic halogenated hydrocarbon polymer bonded to at least one layer (C) based on thermoplastic nonhalogenated polymer incompatible with (A). The structures with multiple polymeric layers according to the invention can therefore comprise one or more layers (A) based on thermoplastic halogenated hydrocarbon polymer bonded to one or more layers (C) based on thermoplastic nonhalogenated polymer incompatible with (A), it being possible for these layers themselves to be bonded to layers of other polymers, of metal and/or of fabric.
The structures with multiple polymeric layers according to the invention preferably comprise a layer (A) based on thermoplastic fluorinated hydrocarbon polymer. In a most preferred way, they comprise a layer (A) based on vinylidene fluoride polymer.
The thermoplastic halogenated hydrocarbon polymer constituting the layer (A) can be identical to or different from the thermoplastic halogenated hydrocarbon polymer (a) which is one of the constituents of the layer (B). Use is advantageously made, as constituent of the layer (A), of a thermoplastic halogenated hydrocarbon polymer of the same nature as the thermoplastic halogenated hydrocarbon polymer (A) which is one of the constituents of the layer (B).
Other polymers compatible with the thermoplastic halogenated hydrocarbon polymer constituting the layer (A) can also be mixed with the latter. An example of such a mixture is a vinylidene fluoride polymer and poly(methyl methacrylate) composition.
The structures with multiple polymeric layers according to the invention comprise a layer (C) based on thermoplastic nonhalogenated hydrocarbon polymer incompatible with (A).
Mention may be made, among thermoplastic nonhalogenated hydrocarbon polymers incompatible with (A), by way of example, of styrene polymers, polycarbonates, polyurethanes, grafted styrene/acrylonitrile/acrylic elastomer copolymers, acrylonitrile/butadiene/styrene copolymers, polyolefins and polyamides, as well as mixtures of these polymers. Polyolefins and polyamides are preferred.
The structures with multiple polymeric layers according to the invention preferably comprise a layer (C) based on thermoplastic nonfluorinated hydrocarbon polymer incompatible with (A).
Mention may be made, among thermoplastic nonfluorinated polymers incompatible with (A).
Mention may be made, among thermoplastic nonfluorinated polymers incompatible with (A), by way of examples, of chlorinated vinyl polymers, styrene polymers, polycarbonates, polyurethanes, grafted styrene/acrylonitrile/acrylic elastomer copolymers, acrylonitrile/butadiene/styrene copolymers, polyolefins and polyamides, and mixtures of these polymers. Polyolefins and polyamides are preferred.
Among polyolefins, the preferred thermoplastic nonhalogenated polymer is polyethylene. In a most preferred way, the thermoplastic nonhalogenated polymer is high density polyethylene.
Among polyamides, the preferred thermoplastic nonhalogenated polymer is polyamide-12.
The term xe2x80x9cpolyolefinsxe2x80x9d is understood to denote homopolymers and copolymers of alpha-olefins, such as ethylene, propylene, butene, hexene, octene and decene. Preferred examples of homopolymers and copolymers of alpha-olefins comprise polyethylene, polypropylene, an ethylene/propylene copolymer, an ethylene/1-butene copolymer, an ethylene/4-methyl-1-pentene copolymer, a propylene/1-butene copolymer, poly(1-butene) and copolymers of the abovementioned alpha-olefins with minor amounts of diolefins or of unsaturated carboxylic acid esters, such as an ethylene/butadiene copolymer, a propylene-butadiene copolymer, an ethylene/vinyl acetate copolymer and an ethylene/ethyl acrylate copolymer. Mention may also be made of thermoplastic rubbers and elastomers based on alpha-olefins (such as, for example, the thermoplastic rubbers of Santoprene(copyright) trade mark). The preferred polyolefin is polyethylene. Mention may be made, as polyethylene, of low density polyethylene, linear low density polyethylene, medium density polyethylene, high density polyethylene or ultra high density polyethylene. Among these polyethylenes, high density polyethylene is particularly preferred.
The term xe2x80x9cpolyamidesxe2x80x9d is understood to denote polymers having polyamide sequences which can be obtained, for example, from caprolactam, from hexamethylenediamine and from adipic acid, from hexamethylenediamine and from sebacic acid, from undecanoic acid and from dodecalactam. Mention may be made, for example, of polyamide-6, polyamide-6,6, polyamide-6,10, polyamide-11 and polyamide-12. Polyamide-12 is preferred among these polyamides.
The structures with multiple polymeric layers according to the invention comprise a layer (B) based on a polymeric adhesive as defined above.
It is understood that each of the constituent polymers of the structures with multiple polymeric layers according to the invention can comprise the conventional additives used during the manufacture or during the processing of this polymer, such as, for example, lubricants, plasticizers, heat stabilizers, light stabilizers, particulate or fibrous fillers, pigments, flame retardants, and the like, provided that these additives do not interfere with the subject-matters of the present invention.
The invention also relates to the process for the preparation of the structures with multiple polymeric layers.
Any conventional technique for assembling polymeric layers can be resorted to in preparing the structures with multiple polymeric layers according to the invention. Mention may be made, by way of example of such techniques, of thermal bonding with the involvement of a solution of the layer (B) based on a polymeric adhesive in a solvent or a mixture of solvents. Other conventional and appropriate techniques for assembling polymeric layers in order to produce the structures with multiple polymeric layers according to the invention are those in which the constituent polymers are processed at a temperature at least equal to their softening temperature. Mention may be made, by way of examples, of hot lamination (hot pressing of preformed polymeric layers, for example, by extrusion), coextrusion, coextrusion-laminating, coextrusion-blow moulding and coextrusion-moulding.
The choice of one or other of these assembling techniques is made according to the use for which the structures with multiple polymeric layers are intended. For example, tubes, pipes, films, sheets and panels are preferably assembled by coextrusion.
Thus, the process for the preparation of structures with multiple polymeric layers is preferably carried out by coextrusion of a layer (A) based on thermoplastic halogenated hydrocarbon polymer and of a layer (C) based on thermoplastic nonhalogenated polymer incompatible with (A), with which layers is coextruded, as an intermediate acting as binder, a layer (B) based on a polymeric adhesive according to the invention.
The thickness of the constituent polymeric layers of the structures with multiple polymeric layers according to the invention and the overall thickness of the said structures are not critical and depend, of course, on the use for which they are intended. The overall thickness of the said structures preferably does not exceed 2 mm.
The thickness of the layer (A) can be at least 100 xcexcm, at least 200 xcexcm or at least 600 xcexcm. The thickness of the layer (B) can be at least 30 xcexcm, at least 100 xcexcm or at least 400 xcexcm. The thickness of the layer (C) can be at least 100 xcexcm, at least 500 xcexcm or at least 800 xcexcm.
The thickness of the layer (A) can alternatively be at most 600 xcexcm, at most 200 xcexcm or at most 100 xcexcm. The thickness of the layer (B) can be at most 400 mm, at most 100 xcexcm or at least 30 xcexcm. The thickness of the layer (C) can be at most 800 xcexcm, at most 500 xcexcm or at most 100 xcexcm.
Preferably, the thickness of the layer (A) is approximately 200 xcexcm. Preferably, the thickness of the layer (B) is approximately 100 xcexcm. Preferably, the thickness of the layer (C) is approximately 500 xcexcm.
The invention also relates to the use of the structures with multiple polymeric layers according to the invention in the manufacture of pipes, tubes, films, sheets, panels and hollow bodies.
The structures with multiple polymeric layers according to the invention can advantageously be used in fields of application requiring good impermeability to liquids and to gases, in combination with high chemical inertia. It is possible to indicate, by way of non-limiting practical examples of uses of structures with multiple polymeric layers according to the invention, tubes intended for the transportation of fuel, of corrosive products or of ultra pure water; pipes which carry gas; films intended for protecting body parts of automobile vehicles from corrosion; composite films, sheets and panels for applications in the field of construction and of agriculture; packing bottles; liquid storage tanks and petrol tanks.
The invention additionally relates to a method which makes it possible to make a layer (A) based on thermoplastic halogenated hydrocarbon polymer adhere to a layer (C) based on thermoplastic nonhalogenated polymer incompatible with (A).
The structures with multiple polymeric layers of the present invention have a good peel strength and combine the advantages of a thermoplastic halogenated hydrocarbon polymer with the properties inherent to the thermoplastic nonhalogenated polymer to which it is bonded.
The examples which follow are intended to illustrate the present invention without, however, limiting the scope thereof.
In all the examples, the peel strength was measured on an Instron Corporation device, after leaving the extruded structures to stand for 7 days, by the following method: the level of adhesion between the PVDF layer and the HDPE or PA layer is measured by carrying out the peel test on 8xc3x976 mm pipes at a rate of 25 mm/min, the result being expressed in N/cm.
The chemical resistance of the structures with multiple polymeric layers was measured after immersion in CTF 2 fuel (mixture of 46.25% of isooctane, of 46.25% of toluene, of 2.5% of ethanol and 5% of methanol) at 60xc2x0 C. for 7, 15 and 30 days. The change in the dimensional characteristics was monitored (for Examples 2, 3 and 4), as well as the resistance to peeling of the structures, both impregnated with fuel and after desorption for 42 hours (for Examples 2 and 3).
The mechanical strength of the structures with multiple polymeric layers was evaluated by the Hoop Stress test, which is a test of resistance to straightforward forward rupture at 60xc2x0 C. under an N2 pressure (for Examples 2, 3 and 4).

Polymeric adhesive and structures with multiple polymeric layers, their process of preparation and their use

Abstract: Structures with multiple polymeric layers comprising a layer (A) based on thermoplastic halogenated hydrocarbon polymer bonded to a layer (C) based on thermoplastic nonhalogenated polymer incompatible with (A) via a layer (B) based on this polymeric adhesive. Process for the preparation of these structures with multiple polymeric layers and use of these structures with multiple polymeric layers in the preparation of pipes, tubes, films, sheets, panels or hollow bodies which can be used in particular in the automobile field.


A method for automatically optimizing computer disks is disclosed which utilizes recorded file usage to determine this optimum location of files on the disk. Each file on the disk is assigned a priority, depending upon its characteristics and frequency of usage. The files on the disk are then reordered on the basis of their priorities (for instance, active files are grouped together in low-numbered sections and volatile files are grouped with free space), thereby minimizing seek time of disk access. The method can be done in the background and optimization can occur on a daily basis.

A computer disk (or simply disk) is a data storage and retrieval device typically comprised of one or more circular recording surfaces connected by a common spindle that spins at high speeds. The data is accessed (i.e., either read or written) by a series of read-write heads, one head per recording surface. All read-write heads are attached to a single moving arm assembly, known as a boom, that moves in and out.
Each recording surface is divided into concentric zones called tracks. The length of each track is divided into a number of segments called sectors. Before a sector can be accessed, the sector must rotate until it is immediately adjacent to its read-write head. The set of tracks adjacent to all the read-write heads at a given instant in time is known as a cylinder.
To access a particular sector, the boom must be moved to the correct cylinder and then the sector must rotate until it is immediately adjacent to its read-write head. The time required to move the boom from one cylinder to another is known as seek time. The time required for a sector to move from its current position to a position immediately adjacent to its read-write head is called latency time.
Seek times are an order of magnitude greater than latency times. Thus, it is desirable to reduce the number of seeks and, when a seek is necessary, to move the boom across as few cylinders as possible.
Sectors are usually numbered, starting with number zero, from the first track on the first cylinder, moving from track to track in a single cylinder, and then moving from cylinder to cylinder. This numbering scheme positions sectors with consecutive numbers on the same cylinder or on an adjacent cylinder.
The operating system of a computer is responsible for allocating sectors to files and maintaining a table, commonly known as the directory, which contains a list of the files that are stored on the disk. The directory also relates which sectors are allocated to each file and which sectors are currently unallocated. The directory is typically stored on the disk in sectors reserved by the operating system for that purpose.
The number of sectors allocated to a file depends on the sector size and the size of the file. Most computer operating systems indiscriminately allocate sectors to a file wherever they are available. In addition, a nonconsecutive allocation scheme is usually used which allows files to become fragmented. Because files tend to grow or shrink over time, the amount of fragmentation can become severe.
To reduce the number and magnitude of seeks, it is desirable to have all sectors of a file stored in consecutively numbered sectors, and it is also desirable to have the files which represent the majority of disk accesses stored consecutively.
Numerous computer programs have been written whose purpose is to monitor and record file usage. In common use, these programs collect data on the number of accesses to each file and the changes in each file's size.
More numerous are computer programs that have been written to increase disk performance by copying files to a different and preferred set of sectors. These programs are referred to as disk optimizers. The simplest disk optimizers merely copy fragmented files to consecutive sectors. The problem with this approach is that as each file is copied, it trades 2 or more blocks of consecutive sectors for 1 block of consecutive sectors. This accelerates the fragmentation of the unallocated sectors and increases the likelihood of new files being fragmented.
More advanced disk optimizers completely reorder a disk by copying files to consecutive sectors, starting with the lowest numbered sector not occupied by the directory, such that no file is fragmented and no sectors are left unallocated between files. This results in all unallocated sectors having consecutive numbers and decreases the rate of future file fragmentation, since new files can easily be allocated to consecutive sectors.
While those advanced disk optimizers are able to eliminate the increased seek times that result from file fragmentation, they do not decrease the seek time required to move the boom from the sectors of one file to the sectors of another file. It is desirable that the files which represent the majority of disk accesses be grouped into neighboring sectors to reduce or eliminate the seek time required to access them.
Further, existing disk optimizers require the computer user to run the disk optimizer program and then start the optimization process. With today's computers, especially personal computers, being used by computer novices, this places an added burden on the user to remember to run the disk optimizer program on a regular basis.

Optimizing a magnetic disk by allocating files by the frequency a file is accessed/updated or by designating a file to a fixed location on a disk


A water closet has a flush tank which reduces the head of flush water presented to a downwardly converging bowl which receives waste to be discharged through an outlet to a siphon trap, the bowl having a rim which causes the flush water to be presented to the trap in a vortex fashion. The trap is U-shaped and includes an upleg and downleg, the upleg having a converging-diverging cross-section to cause the dischrge to be pushed quickly from the bowl into the downleg, which becomes filled and creates a siphon. As waste travels down the downleg it passes through an expansion chamber which imparts a swirling movement to the waste and is again restricted at the outlet, which prevents air from entering the trapway and breaking the siphon.

The present invention generally relates to a water closet and more particularly to a flush water arrangement to minimize the amount of water expended during the flushing operation.
A water closet typically includes a flush tank, a bowl, and a siphon trap to discharge waste from the bowl and prevent gases and waste water from flowing back into the bowl. Efficient water closet performance is a balance between that volume of falling water needed to fill the bowl, either directly from the tank or indirectly from a flush rim which encircles the bowl, and the rate of flow of flush water into the trap required to start and maintain a vacuum in the siphon trap during the flush operation.
Residential homes and buildings are typically equipped with only a single water supply system providing only potable water, irrespective of the uses intended thereof by the resident. Water conservation is now important, especially in the various sunbelt states, and unnecessary consumption of potable water from water closet usage represents an area where water conservation can be achieved. For example, while a typical U.S. water closet consumes about 3.0 gallons of flush water, a conventional European water closet is more water efficient and only uses about 1.5 gallons of water in a thrust-type flushing action. However, this thrust-type action lacks a swirling action which is necessary to clean the interior sidewalls of the bowl. A desirable water closet would efficiently utilize the lower amount of water without sacrificing the benefits gained by thrust and swirling action imparted by the flush water.
One approach to save water is to make the water closet smaller and equip the closet with restrictors to limit the flush water from the tank and thereby render the flushing water more effective. While use of a separate device constitutes a step in the right direction, it would be desirable to have a self-contained water closet which reduces the amount of water required per flush by making the flushing operation more efficient.
A slow discharge of waste has a further unexpected disadvantage. As the discharge leaves the closet it must travel a significant distance to reach the community sanitary system. If the sewage pipes are too great in diameter, the waste will not fill the pipe and tend to form on the pipe wall, resulting in clogged lines. A faster discharge will obviate this situation by acting to scrub the pipe walls.
Accordingly, an object of the invention is provision of a water closet which efficiently uses a substantially reduced head of flush water that cleans the bowl without appreciably affecting the flushing action of the water being discharged and without raising the average head under which this smaller amount of flushing water is delivered.
In accordance with this invention there is provided a water closet including a frusto-pyramidal flush tank expanding vertically downwardly, a downwardly converging bowl including a top flushing rim section receiving flush water from the tank and a lower outlet opening for discharging waste material from the bowl, a conduit for supplying fresh flush water from the tank to the bowl, and a trapway connecting the lower outlet of the bowl to the discharge opening, the bottom part of the bowl and trapway forming a water trap for the sealing function. The trapway forms a continuous passageway described by a specially configured inverted "U" which includes an upleg portion which extends vertically upward from an orifice that defines a contracting expanding nozzle where connected to the bowl outlet, a transition portion which defines the free water level in the main part of the bowl, and a downleg portion which snakes vertically downward from the transition to a discharge opening whereby to pass the waste from the closet. The rim section rapidly supplies fresh flush water to the bowl in a vortex motion to center the waste for entrance into the trapway. The orifice adjacent the bowl outlet communicates waste from the water trap and increases the velocity of the effluent from the bowl. Thereafter, the upleg passage expands in cross-section to receive all waste discharged from the bowl. The transition portion is reduced in cross-section to rapidly become filled and create a siphon in the downleg. As the waste material travels down the downleg the passage expands to form an expansion chamber and then contracts to form an orifice adjacent the discharge opening, the chamber cooperating with the downleg to impart a swirling movement in the waste flow to prevent entry of air into the downleg orifice which could break the siphon action.
Advantageously, the upleg portion allows the waste to be accelerated from the bowl ahead of the flush water with the flush water head rapidly emptying into the bowl to provide the acceleration. Provision of an expansion chamber adjacent the inlet and outlet, respectively, surprisingly allows the siphon action to initiate sooner and not be disturbed during the flushing. This results in substantially less flush water being required for a like flush.
Slow flush water input develops less siphon action in the trap resulting in the waste in the bowl water trap tending to rise to the top of the free surface of the water in the bowl and be the last to be discharged from the bowl. Advantageously, the downwardly converging bowl with the slotted water feed rim rapidly imparts a swirling action to scrub the bowl wall and center the waste for discharge, and the area increase in the upleg, adjacent the transition portion of the closet, defines an expansion chamber that assists in rapid movement of waste material to fill the downleg and start the siphon. The expansion chamber in the downleg adjacent the discharge opening imparts a swirling movement to the waste to prevent turbulence in the flush water, thereby inhibiting air which could break the siphon from entering the downleg.
Other advantages and features will become apparent from the following specification taken in connection with the accompanying drawings.


A die (100) is provided with: a cavity which can contain a molten resin; a micro-structure (102) provided on a molding transfer surface (101) forming the cavity such that the fine structure protrudes to the cavity side from the molding transfer surface (101); and a anti-shrinkage convex section (103) protruding higher than the micro-structure (102) to the cavity side from one surface. A molten resin is applied to the die (100) and the surface of the die is relatively removed in the order of the micro-structure (102) and the anti-shrinkage convex section (103) from a resin substrate (001) formed by solidifying the resin.

Devices referred to as microanalysis chips or μTAS (Micro Total Analysis Systems) have been put to practical use, in which using a microfabrication technology, micro-channels and circuits are formed on a silicon or glass substrate, and thereby chemical reaction, separation, or analysis is carried out in a micro-space by introducing a liquid sample such as a nucleic acid, protein, or blood into such micro-channels. It is conceivable that these micro-channel chips have such advantages that the used amount of a sample or a reagent or the discharge amount of waste liquid is reduced, and small-foot print, portable, and inexpensive systems are realized.
Micro-channel chips are manufactured in such a manner that 2 members in which at least one member thereof has been subjected to microfabrication are bonded together. Conventionally, for micro-channel chips, glass substrates have been used and various microfabrication methods have been proposed. However, such glass substrates are unsuitable for mass production and exhibit extremely high cost. Therefore, the development of resin micro-channel chips, which are inexpensive and disposable, has been desired.
As a method for manufacturing a resin micro-channel chip, a method for joining a resin substrate in which a channel groove is formed and a resin substrate to cover a channel groove is available. To join resin substrates together, listed are a welding method to join resin substrates by heating using a heating plate, hot air, a heating roll, ultrasound, vibration, or a laser, a joining method to join resin substrates using an adhesive or a solvent a joining method utilizing adhesion properties of resin substrates themselves; and a substrate joining method via surface treatment such as plasma treatment for resin substrates (for example, refer to Patent Document 1).
FIG. 10 is a schematic cross-sectional view in which a resin substrate has been formed by pouring a resin into a conventional micro-channel chip molding die. When a resin substrate is joined, as shown in FIG. 10, a melted resin is poured into a micro-channel chip molding die 100 (the portion expressed by oblique lines) and then cooled to mold a resin substrate 001 (the filled-in portion) having a channel groove. The micro-channel chip molding die 100 has a micro-structure 102 to carry out transfer to a surface 101 for transferring a channel groove to a resin substrate (hereinafter referred to as a "molding transfer surface 101"). Then, the micro-channel chip molding die 100 transfers a micro-structure 102 provided for its own molding transfer surface 101 to a poured resin to mold a micro-channel 002 as shown in FIG. 11. FIG. 11 is a schematic cross-sectional view showing the time of mold release molding (releasing a resin substrate from a die) after a resin has been poured into a conventional micro-channel chip molding die.
However, as described in Patent Document 1, in molding in which a micro-channel chip molding die 100 having a micro-structure on the molding transfer surface is used, due to the effect of molding shrinkage with cooling of a resin substrate 001 itself and the runner section being a section to pour a resin into a die, the resin in the edge portion of the micro-structure is raised or broken during releasing. Thereby, as shown in FIG. 11, there occurs a phenomenon in which deformation 003 is generated in part of a resin substrate 001 having been removed from a die 100 in the order of submicron—about 5 μm. In this molded resin substrate 001, for joining as described above, the joining surface (the portion where 2 resin substrates are bonded) in which a micro-channel 002 is formed is required to exhibit high flatness. Namely, when the flatness of the joining surface is degraded due to deformation occurrence as described above, it may be difficult to join resin substrates 001 or to form a micro-channel 002.

Method for manufacturing micro-channel, die for molding micro-channel chip, and micro-channel chip


An impedance blocking filter circuit is used in telecommunication systems for interconnecting between incoming telephone lines carrying Digital Subscriber Line (DSL) signals and a customer""s terminal equipment in order to block impedances above a desired frequency. The impedance blocking filter circuit includes a low pass filter circuit having at least one capacitive pole providing component. The impedance blocking filter circuit also includes a tank circuit coupled in series with the at least one capacitive pole providing component to provide impedance matching for the customer""s terminal equipment.

The present invention relates generally to telecommunication systems. More particularly, the present invention relates to impedance blocking filter circuits used in telecommunication systems for interconnecting between incoming telephone lines from a telephone company""s central office and subscriber or customer telephone equipment.
Frequently, subscribers or customers of telephone service also have, in addition to one or more telephone handsets, a personal computer which requires telephone line access to the Internet or other computer networks. As is known in the art, a computer user can in some instances receive DSL (an acronym for Digital Subscriber Line) signals from the Internet over the same telephone lines via an Internet Server Provider (ISP). In order to increase the speed of downloading of information from the Internet, a DSL network interface is typically purchased and installed between the incoming telephone lines and the user""s computer. However, since one or more of the telephone subscriber""s terminal equipment devices (such as telephone sets, facsimile machines and/or answering devices) may also be connected to the same incoming telephone lines via internal house wiring, DSL interference problems may be caused by the terminal equipment. This can significantly limit or reduce the data rate of the DSL signals.
Telecommunication industry standards, such as described in ANSI""s (American National Standard Institute) draft document T1E1.4/2001-007R, generally require the use of impedance blocking circuits between DSL lines from a phone company and a subscriber""s terminal equipment (telephone handsets, fax machines, etc). Impedance blocking filter circuits for such use are known. For example, U.S. Pat. Nos. 6,181,777 and 6,212,259, each to F. Kiko and entitled IMPEDENCE BLOCKING FILTER CIRCUIT, teach circuits which can be used for this purpose. However, some impedance matching circuits designed for this purpose are fairly complex. As a result, some of these circuits are more expensive to produce than is desired. Further, some of these impedance matching circuits are relatively difficult to adjust for use with different telephone systems having different impedance matching and other requirements.
Accordingly, it would be desirable to provide an impedance matching or blocking filter circuit, for connection between a DSL line and a customer""s telephone terminal equipment, which is inexpensive to manufacture and easily adaptable to different telephone systems.
An impedance blocking filter circuit is used in telecommunication systems for interconnecting between incoming telephone lines carrying Digital Subscriber Line (DSL) signals and a customer""s terminal equipment in order to block impedances above a desired frequency. The impedance blocking filter circuit includes a low pass filter circuit having at least one capacitive pole providing component. The impedance blocking filter circuit also includes a tank circuit coupled in series with the at least one capacitive pole providing component to provide impedance matching for the customer""s terminal equipment.

Impedance blocking filter circuit for digital subscriber line communication systems


Disclosed are methods for reducing the degree of underetching and particulate contamination occurring during dry non-isotropic etching of a polycide layer on the surface of a silicon wafer maintained in a wafer holder wherein the backside of the holder is cooled with a stream of helium gas. Specifically, in the disclosed methods, dry non-isotropic etching of the polycide layer is conducted either in the absence of backside cooling or the helium gas flow utilized in backside cooling is maintained at a pressure of no more than 3 torr.

1. Field of the Invention
This invention is directed to methods for reducing the degree of underetching and particulate contamination occurring during dry non-isotropic etching of a polycide layer on the surface of a silicon wafer maintained in a wafer holder wherein the backside of the holder is cooled with a stream of helium gas. Specifically, in the methods of this invention, dry non-isotropic etching of the polycide layer is conducted either in the absence of backside cooling or the helium gas flow utilized in backside cooling is maintained at a pressure of no more than 3 torr.
2. State of the Art
The formation of non-isotropic patterns (i.e., essentially vertical etch profiles) on the surface of silicon wafers is essential when the thickness of the film being etched is comparable to the minimum pattern dimensions of the to-be-formed features. For example, in very large scale integration (VLSI) devices, many of the films have thickness on the order of about 0.5 to 1 microns (.mu.m) whereas the to-be-formed patterns are on the order of about 1 to 2 .mu.m. Accordingly, undercutting which accompanies typical isotropic etching methods (e.g., wet etching) becomes intolerable at these dimensions. See, for example, Wolf, "Silicon Processing for the VLSI Era", Vol. 1, Chapter 16 ("Dry Etching for VLSI Fabrication"), Lattice Press, Sunset Beach, Calif. (1986).
In view of the above, dry non-isotropic etching procedures have been developed to transfer such patterns onto silicon wafers including, by way of example, reactive ion etching, reactive ion beam etching, electron beam etching, plasma etching, and the like. Common to such dry non-isotropic etching procedures is the use of a reaction chamber wherein the silicon wafer to be etched is placed in a wafer holder. In addition to holding the wafer, the wafer holder is also used to maintain a constant wafer temperature which, among other factors, is important to ensure constant etch rates on the wafer. Typically, the wafer is maintained between 20.degree. and 60.degree. C. during dry non-isotopic etching and, if the wafer temperature is uneven over its surface, then areas of the wafer which are at higher temperatures will tend to etch faster then areas of the wafer maintained at lower temperatures. In turn, uneven etch rates can provide for undesirable uneven patterning which can reduce the degree of non-isotropic etching.
Suitable wafer holders include electrodes (which can impart a low level of heat to the wafer to maintain constant wafer surface temperatures), inert materials (which can act as a heat sink during non-isotropic etching to maintain constant wafer surface temperatures), and the like. In general, a stream of helium gas is permitted to flow to the backside of the wafer holder (the surface of the holder opposite the wafer) to further ensure constant wafer temperature which procedure is referred to as "backside cooling". Typically, in backside cooling, the flow of helium gas is set to maintain a pressure of about 10-14 tort on the backside of the wafer holder.
Notwithstanding the advantages of dry non-isotropic etching, serious problems with underetching and particulate formation are encountered when such etching is employed to remove polycides from the wafer surface. Specifically, refractory metal polycides (e.g., tungsten silicide (WSi.sub.2), molybdenum silicide (MoSi.sub.2), and the like) are employed at numerous sites of the to-be-formed circuits elements including, by way of example, metal interconnect technology, Si-gate technology, and the like, because such silicides have lower resistance, i.e., sheet resistance, as compared to polysilicon. In turn, lower sheet resistance permits the semiconductor device to be operated under faster real time conditions thereby enhancing the operating speed of the device.
In forming a layer of refractory metal polycide on the surface of such circuit elements, a layer of refractory metal or refractory metal silicide is first deposited over the entire surface of the wafer. When a refractory metal is deposited, the metal is then converted to a metal silicide by conventional methods such as thermal annealing. In either case, a layer of resist is then patterned over the surface of the wafer so as to define the to-be-formed circuit elements containing a surface of metal silicide. Next, the wafer surface is subjected to dry non-isotropic etching so as to remove the metal silicide in all areas except under the resist. Upon removal of the resist layer, a surface layer of metal silicide is found only at the desired circuit features.
It has been found, however, that the dry non-isotropic etching of the metal silicide layer on the surface of a silicon wafer utilizing backside cooling results in underetching of the wafer coupled with gross residues across the wafer surface. Both phenomena are severely deleterious to the effectiveness of the etch process as well as the wafer produced thereby. Specifically, underetching of the wafer surface and particulate contamination on the surface of the wafer can alter the functionality of the to-be-formed circuit elements.

Reduction of polycide residues through helium backside pressure control during dry etching


A coordinate measuring device includes a carrier that can be rotated automatically about two axes and that can be directed toward a measuring aid. The following are arranged on the carrier so as to be able to move together: an optical distance measuring device for measuring the distance to the measuring aid; an infrared light source for emitting an infrared target beam, which is visible as an infrared target point when reflected on the measuring aid; a fine target detection unit for determining a fine position of the infrared target point on a first position detection sensor, wherein the fine target detection unit and the distance measuring device have a common exit lens system; a second light source, the light of which is visible as a second target point when reflected on the measuring aid; a rough target detection unit for determining a rough position of the second target point on a second position detection sensor.

1. Field of the Invention
The invention relates to a coordinate measurement apparatus and to a method for operating a coordinate measurement apparatus, according to the preamble of the respective independent patent claims.
2. Description of Related Art
Coordinate measurement apparatus, often called laser trackers, are applied for the measurement of the position moving target points. The term laser trackers is to be understood as devices which comprise at least one distance meter operating with a focused laser beam (indicated as measurement beam in the following description). For example, the direction of the measurement beam is set to the target point with the help of a mirror rotatable about two axes, and is detected with angle sensors assigned to the rotation axes. The target point to be measured is provided with a retroreflector (in particular cube-corner prism or arrangement of three mirrors which are perpendicular to one another), wherein the retroreflector reflects the measurement beam of the laser tracker which is incident thereon, back to this laser tracker. Thereby, the reflected measurement beam runs coaxially to the emitted measurement beam if the measurement beam is incident on the reflector in an exactly centric manner, and offset parallel thereto, if the measurement beam is not centrically incident on the reflector. One concludes an absolute distance between the laser tracker and the target point and/or a change of this distance from a comparison of the emitted and reflected laser light, depending on the embodiment of the tracker (absolute distance meter or interferometer). The position of the reflector or of the target point relative to the tracker is computed from the angles detected by the angle sensors and from the distance detected by the distance meter.
A part of the reflected measurement beam is usually guided onto a PSD (position sensitive device). One may deduce the parallel shifting of the reflected measurement beam relative to the emitted measurement beam from the position, in which the reflected measurement beam is incident on the light-sensitive surface of the PSD. The measurement data which is determined by way of this defines the parallel offset of the reflected measurement beam and is used for a control of the measurement beam direction, in a manner such that the measurement beam follows the target point (tracking), when this moves. This means that by way of a suitable change of the measurement beam direction or of the alignment of the mirror aligning the measurement beam, one ensures that the parallel offset between the emitted and the reflected measurement beam is reduced or remains as small as possible.
Various arrangements of optical distance meters and picture detection sensors are described in WO 2007/079600 A1. In one arrangement (FIG. 4), an overview camera (104), a position-sensitive diode (109) operating in the visible spectral range and a zoom camera (106) are all coupled into the measurement light path of a distance measurement device (200, 300). The position-sensitive diode (109) must operate in the visible range, in order to be able to also use a precise measurement light beam of a He-Ne laser of an interferometer. A reflector illumination (110) is arranged outside the measurement light path and operates in the visible range in a manner matched to the overview camera, for detecting reflected targets. The overview camera must operate in the visible range, in order to be able to produce pictures of a good quality, in particular colour pictures.
U.S. Pat. No. 6,504,602 B1 describes a theolodite with a distance measurement apparatus. An automatic target recognition uses radiated light in the visible range or in the near infrared range.
EP 2 071 283 A2 describes the use of two separate cameras with wide and narrow viewing angles, in each case with their own light source coupled into the camera optical system. The cameras are arranged separately from one another, one of which with the viewing axis collinear to a distance meter, and operate with visible light. A target recognition is accomplished in each case by way of switching the respective light source on/off and a subsequent difference formation from the respective pictures.

This patent is subject to a terminal disclaimer.


Controlling the reductive capacity of an aqueous alkaline slurry (23) in a wet scrubber makes it possible to accurately control the mercury emission from the scrubber to a desired value. One method of controlling the reductive capacity of the slurry is to measure the reduction-oxidation potential (“redox potential”) of the aqueous alkaline slurry (23) and to add or remove substances that affect the redox potential and thus the reductive capacity of the slurry. In wet scrubbers in which limestone is used for absorption of acid gases and where a gypsum slurry is circulated, it has been found to be an attractive solution to control the amount of oxidation air blown into the scrubber in order to control the redox potential and thereby the mercury emissions.

(1) Field
The disclosed subject matter generally relates to controlling an amount of mercury discharged to an environment incident to the combustion of a fuel source containing mercury or mercury compounds, and more particularly to controlling the mercury discharge in a combustion flue gas which is subjected to a wet scrubbing operation.
(2) Description of the Related Art
Combustion of fuel sources such as coal produces a waste gas, referred to as "flue gas" that is to be emitted into an environment, such as the atmosphere. The fuel sources typically contain sulfur and sulfur compounds which are converted in the combustion process to gaseous species, including sulfur oxides, which then exist as such in the resulting flue gas. The fuel sources typically also contain elemental mercury or mercury compounds which are converted in the combustion process to, and exist in the flue gas as, gaseous elemental mercury or gaseous ionic mercury species.
Accordingly, flue gas contains particles, noxious substances and other impurities that are considered to be environmental contaminants. Prior to being emitted into the atmosphere via a smoke stack ("stack"), the flue gas undergoes a cleansing or purification process. In coal combustion, one aspect of this purification process is normally a desulfurization system, such as a wet scrubbing operation known as a wet flue gas desulfurization (WFGD) system.
Sulfur oxides are removed from flue gas using a WFGD system by introducing an aqueous alkaline slurry to a scrubber tower of the WFGD system. The aqueous alkaline slurry typically includes a basic material that will interact with contaminants to remove them from the flue gas. Examples of basic materials that are useful in the aqueous alkaline slurry include, but are not limited to: lime, limestone, magnesium, calcium sulfate, and the like, and combinations thereof.
Recently, there has been an increased focus on the removal of mercury. Presently, there are various methods for removing mercury from flue gas. Those methods include, but are not limited to: addition of oxidizing agents in a boiler upstream of the flue gas emission control system and then removing it with scrubbers; addition of reactants to bind mercury and remove it from the flue gas; and utilization of particular coal or fuel that minimizes the amount of mercury released when the coal or fuel is burned.
It has been shown that a number of generally known methods of mercury removal are effective to produce mercury salts, which can be dissolved and removed by the aqueous alkaline slurry used in the wet scrubbing operation. Some of these methods include the addition of halogen or halogen compounds, such as bromine, to the coal or to the flue gas upstream of the wet scrubbing operation, to provide oxidation of elemental mercury to ionic mercury and formation of mercury salts, which are then dissolved in the aqueous alkaline slurry incident to the sulfur oxide removal processes. However, the removal of mercury in the aqueous alkaline slurry of a wet scrubber has proven to be difficult to control and it is not easily predicted when designing a flue gas cleaning system with respect to mercury removal. The desired emission guarantee levels are often as low as 1 mg/Nm3 of mercury, which corresponds to a very high mercury removal efficiency in the wet scrubber.

Method of mercury removal in a wet flue gas desulfurization system


A particle discharge apparatus includes cylindrical particle discharge unit(s) having toner dispensing outlet(s) provided at upper portion(s) on one side of particle discharge unit(s), and particle discharge outlet(s) provided at lower portion(s) on the other side of particle discharge unit(s); and conveyor screw(s), provided at the interior of particle discharge unit(s), having rotatable shaft(s) and helical conveyor vane(s) secured to rotatable shaft(s). The conveyor vane(s) is/are divided into first vane segment(s) and second vane segment(s); and wherein there is/are vaneless region(s), where no portion of conveyor vane(s) is present, between first vane segment(s) and second vane segment(s).

This application claims priority under 35 USC 119(a) to Patent Application No. 2004-76709 filed in Japan on 17 Mar. 2004, the content of which is hereby incorporated herein by reference in its entirety.
I. Field of Technology
The present invention relates to a particle discharge apparatus which discharges particles; more particularly, the present invention pertains to a particle discharge apparatus capable of being used with toner cartridge(s) or the like supplying developer (toner) to development apparatus(es) in copier(s) and/or other such electrophotographic image forming apparatus(es), and also pertains to an image forming apparatus employing such particle discharge apparatus(es).
II. Related Art and Other Considerations
Conventional image forming apparatuses employ finely toner particles as a developer. Toner cartridges removably installed on development apparatuses are used to supply such toner to internal development apparatuses.
As shown in FIG. 5, such a toner cartridge might be equipped with a cylindrical toner particle discharge unit 102 arranged horizontally, by way of toner dispensing outlet 101a, beneath cartridge main body 101, which contains the toner. Toner particle discharge unit 102 is provided with toner particle discharge outlet 103 at the bottom circumferential surface thereof. Furthermore, provided at toner dispensing outlet 101a is toner supply roller 101b, which, when driven, serves to quantitatively supply toner from the interior of cartridge main body 101 to toner particle discharge unit 102. Roller 101b is formed from sponge or the like which, when toner supply roller 101b is stopped, presses against toner dispensing outlet 101a so as to prevent toner from pouring out from toner particle discharge outlet 103.
Provided at the interior of toner particle discharge unit 102 is conveyor screw 105. Conveyor screw 105 comprises rotatable shaft 106, and conveyor vane 107 which is secured to this rotatable shaft 106 and which is formed in helically continuous fashion. Furthermore, mounted on toner particle discharge unit 102 so as to cover the outside circumferential surface thereof is cylindrical shutter cap 110. This shutter cap 110 is disposed so as to permit sliding axially relative to toner particle discharge unit 102. Moreover, when shutter cap 110 is made to overcome an elastic force from thrust spring 120 which is fitted onto the outside of toner particle discharge unit 102 and is made to slide in one direction X1, causing opening 111 formed in shutter cap 110 to line up with the toner particle discharge outlet 103 and open toner particle discharge outlet 103, toner can be supplied to the interior of a development apparatus, not shown, which is arranged beneath toner particle discharge unit 102.
With a toner cartridge constructed in such fashion, when there is no longer any toner present within the cartridge main body, the toner cartridge is removed from the development apparatus main body and filled with toner, following which it is again loaded into the development apparatus main body. In such case, to prevent leakage from toner particle discharge outlet 103 of toner remaining within the cartridge main body when the toner cartridge is removed from the development apparatus main body, the restoring force from thrust spring 120 causes shutter cap 110 to slide in the other direction X2 so as to close toner particle discharge outlet 103 (see, e.g., Japanese Patent Application Publication Kokai No. 2000-98722).
However, with conventional toner cartridges such as have been described above, as there will be toner which collects and remains present all the way along conveyor vane 107 when conveyor vane 107 of conveyor screw 105 (provided within toner particle discharge unit 101) is not being driven in rotational fashion. Air trapped within the toner can problematically the internal pressure of the toner which has collected thereat to increase at such time. This internal pressure causes the toner which has collected thereat to pour out in extruded fashion from toner particle discharge outlet 103.
An object of the present technology is to provide a particle discharge apparatus employing stratagem(s) to reduce internal pressure(s) within particle discharge unit(s) when conveyor vane(s) is/are not driven in rotational fashion, so as to make it possible to definitively prevent toner which has collected thereat from pouring out therefrom, and to provide an image forming apparatus employing such particle discharge apparatus(es).

Particle discharge apparatus and image forming apparatus