A spirometer set-up with an analogue to digital converter to a computer chain which allows the use of the merit function of the flow-volume curve for the discrimination between healthy persons and those who have a mechanical pulmonary function disorder, and the exact area under the flow-volume curve of lung mechanics to follow the progression of said lung disorder.

1. Field of the Invention
The invention relates to spirometers that are electrically connected to a computer through an analogue to digital converter. From the digital values every 10 milliseconds collected software calculates all the successive flow and volume values of a breathing exercise and graphically presents conventional mechanical lung functions and the related flow-volume curve, while it more particularly permutes the parameters that determine the shape of the flow-volume curve. To compute comprehensive new lung indices the figure-of-merit function of the maximum expiratory flow-volume curve, subsequently called the merit function, is developed to make quantitation of both the area under and the shape of that curve feasible. The calculated exact maximum expiratory flow-volume area under that curve, subsequently called the FV area, portrays the amount of oxygen that a person can collect. Indices developed from coefficients and exponents of the merit or the flow-volume's essential mathematical function make the hitherto impossible quantisation of the shape of the flow-volume curve workable.
Evaluation of old mechanical lung indices up to now used in pulmonary diagnostics, was complicated and not exact. Their values also differentiate poorly between distinctive lung function disorders and between lung patients and healthy people. The for the invention designed comprehensive mechanical lung indices open complete new perspectives in lung diagnostics.
2. Description of the Related Art Including Information Disclosed Under 374 CRF 1.97 and 1.98
Conventionally, in epidemiological research of lung diseases and diagnostic evaluation of patients, the forced expiratory flow-volume curve obtained by a forced breathing manoeuvre is widely used. Related lung indices, representing single points on that curve, may show flow limitation, the curve shape was visually used in the decision making process. The older lung indices do not take into account that the whole FV area represents the labor the thorax and lungs are able to achieve.
Conventional lung indices, like the forced vital capacity (FVC), the one second volume (FEV1), the FEV1/FVC ratio, the maximum mid expiratory flow rate (MMEFR), the peak flow rate (PEF or MEFR) and the average flow between two fixed volume percentages (FEF25-75%VC etc.) take into consideration only one or two points on the flow-volume curve.
They require complex pulmonary diagnostic systems, as presented by Dunning et al U.S. Pat. No. 4,296,756 and Snow et al U.S. Pat. No. 4,796,639. These diagnostic systems use several parameters and still do not differentiate successfully. The discriminant analysis of lung indices does not make a significant difference between those with severe symptoms and the relative healthy people. Only when we take the whole area under the flow-volume curve into account do these separation of the distribution curves becomes complete, as shown in the compilation of the Irian Jaya survey (see document 3).
Vermaak and others (see publication 1), used the area of a triangle in the flow-volume curve. The triangle is situated between the origin, the point of maximum volume and the point of maximum flow. To get an estimate of the area under the flow-volume curve the triangle was multiplied with an experimentally found average coefficient. The calculation of this area, however, did not use all the estimable points on the curves. The incorporation of an experimentally average coefficient, makes the calculation conditional to gender and anthropological differences, and neglect individual or disease related alterations. An area was also used for the mean transit time (MTT) because the area under a volume-time curve divided by the volume expired, gives the mean time it takes to expire. Some improvement in the discriminant analysis with conventional mechanical lung indices emerges. Calculating different areas of the curve (FIG. 7), namely after point zero, the point of reflection, and the one-second time point, gives the mean transit time of different parts of the volume-time curve (MTTN, MTTF, MTT1 respectively). The calculation gives an average time, depends only partially on the shape of the curve and gives no indication of the labor carried out to supply oxygen.
It is therefore an object of the present invention to provide the means to calculate the area under the flow-volume curve, by utilising all the digital values collected from the individual under investigation. The result is the maximum expiratory flow-volume area (MEFVA) in squares liters per second (l.sup.2 /sec). It is an exact measurement of a person's oxygen supply capacity, and is independent of the shape of the curve. It takes into account all estimable points on the curve, sampled every one hundredth of a second.
It is further an objective of the present invention, to qualify the shape of the flow-volume curve, which depend on its merit function; the function that measures the agreement between the data and the model with a particular choice of parameters.
With the merit function developed by the inventor we can model the data. However, collection of data never occurs without measurement errors. Calculations, therefore, can not be carried out with mathematical precision but have to be tested for their goodness-of-fit. As the merit function turned out to be nonlinear, we used the Levenberg-Marquardt iterative minimisation method, as described in publication 2 from Cambridge University Press 1989. The numerical calculation makes it possible to calculate the two coefficients and four exponents of the function.
The final chi-square of the numerical calculations (with this kind of function) must be lower than the number of equations minus the number of parameters (six). A chi-square, just above the norm, can still be acceptable, if the curve from the calculated formula as shown in the graphical presentation covers or fits the measured flow-volume curve. When measurement errors are not normally distributed, and inequalities are inappropriately high, but the curves cover nicely, we can still use the results. So far the parameters of the merit function have nor been used as a diagnostic tool to quantitate the shape of the flow-volume curves.
The inventor used a dry spirometer with a hinge pivoting through a vertical line, further on called the spirometer with a vertical hinge. The spirometer electronically samples digital values every hundredth of a second. The digital values are stored in an array, and represent changes in volume during the breathing exercise. The software calculates a calibration factor from the digital values before, and after, injection of two liters of air into the spirometer. Temperature and altitude readings are incorporated into the data. Flow and volume values are estimated, from this data, using a calibration factor and a body-temperature pressure-saturated (BTPS) correction factor, selected from a data base.
It would be possible to connect a `Portable Flow-Type Spirometer With Improved Accuracy` as disclosed by Hankinson et al. U.S. Pat. No. 5,277,196, instead of the dry spirometer used. Such a flow-type spirometer was not used in conjunction with the invention. It though would have made the outfit smaller but was not available by the time of the survey (1998-92). The Hankinson is more accurate than the earlier hot-wire flow-type spirometric systems that showed nonlinearity and a sensor drift.
The volume-type spirometer used in the survey maintains linearity by the arcing movements of the moving panel point being referred to a potentiometer. There is no zero drift because bellow movements begin at a start block. Hankinson claims that the updated flow-type spirometer is also linear and has no zero-drift. Consequently the systems are compatible, except for the volume which will need to be calculated from the flow values. Mobility and hardness of the flow-volume device as disclosed by Kraemer and others in U.S. Pat. No. 5,357,975, however, works at the expense of manually iterated measurements to shape a flow-volume curve. The shape, which is so important in diagnostics, deteriorates into a triangle without any guarantee that the area reflects the oxygen supply capacity.
The invention which uses a merit function of a flow-volume curve can be used, in epidemiological surveys as well as for clinical and doctor practices, and no remote controls, like in the Dunning' Remote Pulmonary Function Tester, are required. It also opens the way to supermarked self-control as done with blood pressure and cholesterol level monitors. The MEFVA gives a good qualitative prognosis of the momentary oxygen supply capacity and shows its change over time. The undimentional values from the coefficient proportionality index (CFI) and exponent proportionality indices (HPI-1 and 2), as described later, have a sharp boundary. This makes lung diagnostics much like a blood sugar level estimate in diabetes. For an explanation refer `Detailed Description of the Invention` under section h.
For clinical use in diagnosis of lung disorders and evaluation of treatment, other functions, like diffusing capacity, residual volume, resistance, alveolar volume and blood gasses, can be better judged when the supply side is defined accurately. In improved bronchial provocation tests as invented by Cloutier (U.S. Pat. No. 5,320,108) for occupational asthma, or in bronchial reactivity studies, in the clinic and by population studies (Woolcock in publication 3), the MEFVA would be of great help.
The vertical hinge of the spirometer manufactured to collect data for the investigation, obliterates the gravitational pull on the bellow in the direction of the volume extension. Garbe (U.S. Pat. No. 4,296,758) and Shipley (U.S. Pat. No. 2,999,495) have a horizontal hinge. Shipley in FIG. 4 clearly shows the influence of gravidity. The bellows, or clocks, of the volume-type spirometer as used by McKenzie (U.S. Pat. No. 642,149) moving up and down, Woldring (U.S. Pat. No. 3,889,672) and Kitrilakis (U.S. Pat. No. 3,889,660) moving sidewards around a horizontal spindle, are all subjected to gravity, which hampers their volume extension. Jones (U.S. Pat. No. 3,533,398) moving sidewards does not has the gravitational pull but needs a lot of valves to direct and thus hamper the air stream. Choksi (U.S. Pat. No. 4,635,647) used a collapsible bellow and could measure only a desired range of airflow. Valdespino et al. (U.S. Pat. No. 4,736,750) used a bellow to proceed from airflow into volume measurements but could only estimate the values FVC, FEV1 and FEV1/FVC.
Holden (U.S. Pat. No. 3,420,225) used two hinges with horizontal spindles to operate under the influence of acceleration forces going toward and being in outer space, the changes in volume measured with a potentiometer. It is obvious that the invention could not have been made with the data from a lung survey in stone age times in the Highlands of Irian Jaya with advise from several universities and without funding using equipment for outer space. Potentiometer movements of the in space used Holden invention, however, are not linear as the bellows move along an arc and do not behave as a triangle (see Description of the Preferred Embodiments). Not to mention yet the hampering friction of the bellows so near to the hinge.
Linearity and independence from gravidity are important preconditions because breathing, limited or not, is a continuous movement, and the Marquardt method can only calculate a continuous function, because it depends on six partial derivatives.
A revolving valve connecting a subject or calibrator to the spirometer or to the spirometer and ambient air also contributes to a smooth, continuous registration of the breathing movement, as no moving valves hamper the airflow like in the McKenzie version. Beaston (U.S. Pat. No. 5,004,013) made a Dripless Coupling Device and Beiter (U.S. Pat. No. 4,931,044) a Blood Collection Valve for fluids. They, however, connect one channel only and would not give the possibility to connect a spirometer to the ambient air while the subject or calibrator are still connected. This is necessary to readjust the start point, to release false pressures and to refresh the interior of the bellows. The Beason valve instead retains the fluid which is already in the apparatus. Pressure release could be done by opening the mouth peace or disconnect the calibrator, but is often not practised in every day life.
Pawelzik et al. (U.S. Pat. No. 5,190,077) made a Switchover Valve and Johnson (U.S. Pat. No. 4,470,429) a three-way valve for fluids that would put the airflow of a breathing manoeuvre into turmoil because of the sharp angles and obstruction of the rotary valves. A four-way valve of this type with the requirements of an 1.5 inch input pipe diameter for a breathing manoeuvre would not match when the spirometer was connected with one of the valves. Only the long large openings like 19 in FIG. 3 make an easy going airflow possible. Eng. E. Vanuytven from Intersoft Electronics, who invented the "MacFactory.TM." for use with the Macintosh computer, was so kind to write me the MacScoop software program in FORTH, to interface "MacFactory.TM." to collect the data.

Area and shape of the flow-volume curve in lung diagnostics


Apparatus and method for quantifying the oil and water fractions of a multi-phase flow stream and their respective flow rates. The hydrocarbon fractions are determined based on information gathered on their respective refractive indices when exposed to particular wavelengths of light.

1. Field of the Invention
This invention relates to an apparatus and method for analyzing oil and water fractions in multi-phase fluid flow. This invention further and more particularly relates to determining the various hydrocarbon fractions in a fluid flow.
2. Background Art
In many situations the monitoring of a changing fluid flow in real time is desired in addition to determining the type of oil being produced without using a computer-intensive technique.
Also, it is necessary to analyze three-phase flow for the relative amounts of water, oil, and gas contained therein, and for distinguishing between the hydrocarbons and water.
It is desirable to make measurements without having to recalibrate each time a measurement is taken. Different material properties require recalibration of currently used equipment. This invention addresses this problem.


The invention features a catheter and methods for delivering drug to tissue at a desired location of the wall of a body lumen. The catheter is constructed for insertion in a body lumen and has a catheter shaft and an expandable portion mounted on the catheter shaft. The expandable portion is expandable to a controlled pressure to fill the cross-section of the body lumen and press against the wall of the body lumen. In one embodiment, at least a portion of the exterior surface of the expandable portion is defined by a coating of a tenaciously adhered swellable hydrogel polymer. Incorporated in the hydrogel polymer is an aqueous solution of a preselected drug to be delivered to the tissue or plaque. The hydrogel polymer and drug are selected to allow rapid release of a desired dosage of the drug from the hydrogel polymer coating during compression of the hydrogel polymer coating against the wall of the lumen when the expandable portion is expanded. In other embodiments the polymer is released from the expandable portion in response to pressure, to coat the wall of the body lumen.

Systemic administration of drugs treats the organism as a whole, even though the disease may be localized, such as occlusion of a duct or vessel. Localization of a drug poses special problems in cases involving the walls of ducts and vessels, since, by nature, these organs serve as transport systems.
Arthrosclerotic disease, for example, causes localized occlusion of the blood vessels resulting from the build-up of plaque. As the deposits increase in size, they reduce the diameter of the arteries and impede blood circulation. Angioplasty, which involves the insertion of catheters, such as balloon catheters, through the occluded region of the blood vessel in order to expand it, has been used to treat arthrosclerosis.
The aftermath of angioplasty in many cases is problematic, due to restenosis, or closing of the vessel, that can occur from causes including mechanical abrasion and the proliferation of smooth muscle cells stimulated by the angioplasty treatment. Restenosis may also occur as a result of clot formation following angioplasty, due to injury to the vessel wall which triggers the natural clot-forming reactions of the blood.

Drug delivery system making use of a hydrogel polymer coating


Methods for rapidly determining earthquake parameters of an earthquake include inputting a seismogram of the earthquake, searching concurrently in pre-established historical seismogram database and theoretical seismogram database by use of an approximate nearest neighbor search method, to find a set of seismograms similar to the input seismogram according to a preset similarity condition, and determining from the set of similar seismograms one or more seismograms matched with the input seismogram, and determining the earthquake parameters from the matched seismograms. With the present invention, it is possible to search in millions of seismograms and determine parameters for an earthquake in a few second, and thus realize rapid and even real-time estimation of earthquake parameters.

An earthquake refers to a sudden movement of the earth's interior caused by the release of stress accumulated along geologic faults or by volcanic activity. The earthquake may includes various quakes of the earth's interior, such as microseismic events caused by industrial activities, dynamite explosions used in petroleum and natural gas exploration, small or large natural earthquakes, and nuclear explosions.
When an earthquake takes place, its waves are recorded by seismic stations (more specific, earthquake recording instruments), we want to infer and report its location, magnitude, and source focal mechanism as fast as possible. Current state-of-the-art technology in this area can detect an earthquake's location shortly after the occurrence of the earthquake using P- and/or S-wave travel time information, but the source focal mechanism has to be analyzed and becomes available in hours or days after the earthquake. Current technology for locating earthquakes and reporting earthquake magnitude also often requires a certain level of expertise to infer and ensure estimation accuracy. In the case of magnitude 9.1 earthquake occurring on Dec. 26, 2004 off the west coast of Northern Sumatra, it was not reported timely because of holidays. As a result, warning of tsunami was not issued timely, which led to severe damages and injuries. Reporting focal mechanism of an earthquake in real time is important. For example, Bouchon, M., Karabulut, H., Aktar, M., Ozalaybey, S., Schmittbuhl, J., and Bouin, M-P. (2011). Extended nucleation of the 1999 Mw 7.6 Izmit Earthquake, Sciences 331, 877-88 analyzed the extended nucleation of the 1999 Mw 7.6 Izmit earthquake and found a sequence of foreshocks whose focal mechanisms indicating similar fault slips before accelerating to dynamic rupture. Obtaining foreshock focal mechanisms in real time may help to develop early warning system or even predict earthquakes. However, deriving earthquake focal mechanism requires efforts such as waveform modeling and inversions, which are usually performed in the following hours or days after earthquakes, and it often requires advanced modeling and computational efforts.
A method for rapid determination of source parameters of an earthquake is desired.

Method and system of determining earthquake parameters, earthquake search engine

University of Science and Technology of China


A self-supporting multifunctional film is provided based on natural poly-phenols such as tannic acid. The self-supporting film composition of the invention contains a tannic acid derivative in which 12% to 24% of hydroxyl groups in tannic acid are bonded via urethane bonds that are formed by way of reactions with cyanate groups. Preferably, the film composition further includes a precursor polymer and 45 to 65% by mass of tannic acid and 55 to 35% by mass of the precursor polymer. Preferably, the precursor polymer has a second linear hydrocarbon compound urethane-bonded to both ends of a first linear hydrocarbon compound, and more preferably a diisocyanate group having an oligoethyene glycol as a spacer. Preferably, the ratio of the urethane bonds contained in the precursor polymer to the hydroxyl groups contained in the tannic acid is (12:88) to (24:76) inclusive in terms of molar ratio.

Tannin is a general term for astringent plant ingredients which are widely found in the plant kingdom and yield polyhydric phenols (polyphenols) by way of hydrolysis, and generally broken down into two lines having fundamentally different chemical structures: hydrolysable tannin and condensed tannin.
However, tannin has limited applications because of being hardly soluble in organic solvents. As well known in the art, this may be solved by substituting at least some of hydroxyl groups contained in the tannin molecules with alkyl ethers or alkyl esters to obtain water-insoluble tannic acid derivatives (see Patent Publication 1).
The Applicant has already come up with a coating material containing tannic acid derivatives (see Patent Publication 2). Tannic acid is found to have significant effects well suited for the food industry, the sporting goods industry and so on wherein antibacterial activity, sterilizing activity, bactericidal activity and so on are required.

Film composition containing a tannic acid derivative and process for producing said film composition

NATIONAL INSTITUTE FOR MATERIALS SCIENCE


The present invention concerns the use of at least one compound A comprising at least one —SH or —S—, M+group, at least one —C-G-C— chain, in which G represents an atom from column 16 of the periodic table, not comprising a carboxy group —C(═O)—OH or —C(═O)—O—, and of a molar mass of between 90 g·mol-1 and 1000 g·mol-1, as an additive in a formulation inhibiting corrosion in metals used in the oil industry, and more generally in any kind of industry involving the drilling of ores or fossil compounds, such as gas or oil, in order to improve both the anti-corrosion performance and the storage stability of same. The invention also concerns said corrosion-inhibiting formulations comprising at least one compound A.

The present invention relates to formulations which inhibition the corrosion of metals used in the oil and gas industry and more specifically in any type of industry for the drilling, completion, stimulation and production of ores or fossil compounds, such as gas, oil, asphalt and others.
Such corrosion-inhibiting formulations are already widely known and the most effective of them generally comprise one or more sulfur-based derivatives, in particular chosen from mercapto alcohols and mercapto acids. Thus, the applications WO 1998/041673, WO 2013/034846 and WO 2013/038100 describe corrosion-inhibiting formulations where the addition of sulfur-based derivatives, for example thioglycolic acid, makes it possible to enhance the performance of said inhibiting formulations. The application WO 2001/012878 A1 describes the use of mercapto alcohol with the same aim of improving the performance of corrosion-inhibiting formulations.
However, it has been observed that the corrosion-inhibiting formulations comprising one or more sulfur-based derivatives, such as those defined above and in particular thioglycolic acid, are not very stable on storage and have a tendency to develop nauseating and undesired odors.
These nauseating odors are probably due to the decomposition of the sulfur-based derivatives and, without being committed by the theory, it is believed today that the sulfur-based derivatives defined above, such as, for example, thioglycolic acid, the mercapto alcohol and others, probably decompose in part to give hydrogen sulfide (H2S) at the storage temperature. The higher the storage temperature, the greater the decomposition of the sulfur-based derivatives, in particular when thioglycolic acid is concerned.
This decomposition phenomenon presents industrial health problems and thus renders these corrosion-inhibiting formulations difficult to use, due to the unpleasant odors which they release, indeed even odors which are dangerous to the users. This is because hydrogen sulfide is toxic, even at very low concentrations in air. Another problem related to the use of some of the sulfur compounds described above is their very high toxicity which makes them extremely dangerous to handle during the manufacture of said corrosion-inhibiting formulations.
The gas and oil industry already uses certain compounds, referred to as H2S scavengers, where they are mainly employed by injection into gas, crude oil or water or aqueous fluid pipes, in order to scavenge (trap, or also neutralize) the acidic entities present in said pipes.
These acidic entities, which are often corrosive, are mainly due to the presence of moisture and of "sour" gases, such as, for example, hydrogen sulfide (H2S) and carbon dioxide (CO2) in the presence of H2S.
In this field, it is today commonly established to classify H2S scavengers into two major families, regenerative scavengers and non-regenerative scavengers.
Mention may be made, among "regenerative" H2S scavengers, for example, of alkanolamines, such as monoethanolamine, diethanolamine or also methylethanolamine.
Mention may be made, among "non-regenerative" H2S scavengers, for example, of triazines and their derivatives, oxidizing agents, such as chlorine dioxide, hypochlorites (for example bleach) or hydrogen peroxide, transition metal salts (such as iron, cobalt, nickel, chromium, copper, zinc or manganese salts, and the like) or aldehydes, such as formaldehyde and glyoxal.
It might thus be envisaged to use such H2S scavengers in order to trap the sulfides resulting from the decomposition of the sulfur-based derivatives present in corrosion-inhibiting compositions. However, the majority of the regenerative scavengers and non-regenerative scavengers suffer from many drawbacks which render them not very suitable for use in corrosion-inhibiting formulations.
Thus, amine-based derivatives, in particular alkanolamines, are not efficient enough in removing the H2S resulting from the decomposition of thioglycolic acid. Oxidizing agents, such as chlorine dioxide, bleach or aqueous hydrogen peroxide solution, are difficult to use because of their corrosiveness, which conflicts with the desired aim.
In addition, the formation of insoluble solids with some of these H2S scavengers and thioglycolic acid in anticorrosion formulations renders these formulations unsuitable for use, since any risk of blocking and clogging of the injection tubes and pipes must be avoided at all costs. Furthermore, aldehydes, such as formaldehyde and glyoxal, are toxic and it is sought to minimize, indeed even avoid, their use.
Furthermore, while these H2S scavengers are generally effective in trapping the hydrogen sulfide present in gas, crude oil or water or aqueous fluid pipes, in order to scavenge (trap, or also neutralize) the acidic entities present in said pipes, it is not established that these H2S scavengers might be effective in stabilizing corrosion-inhibiting formulations and preventing their decomposition in order to avoid the release of H2S.
Moreover, the addition of such an H2S scavenger to corrosion-inhibiting formulations would correspond to an additional stage during the preparation of such formulations and would thus result in an increase in the manufacturing and sales costs of these formulations.
There consequently remains a need for formulations which are effective from the viewpoint of the inhibition of corrosion, comprising at least one sulfur-based compound which makes it possible to enhance the performance of said inhibiting formulations, which are not or only slightly toxic and/or harmful, which are stable on storage and which are easy and economically possible to prepare.
Thus, one objective of the present invention is to make available anti-corrosion formulations comprising at least one sulfur-based derivative and which are stable on storage, that is to say which do not generate or which generate little in the way of unpleasant odors over time. Another objective of the present invention is to make available stable anti-corrosion formulations which are particularly suitable and effective for the prevention and treatment of corrosion in the field of oil or gas extraction and the extraction of ores in general.
Another objective of the invention is to make available stable anti-corrosion formulations which are suitable and effective for the prevention and treatment of corrosion in the field of oil or gas extraction and the extraction of ores, said formulations being non-toxic or not very toxic, that is to say comprising no or very little in the way of compounds which might prove to be toxic, harmful and/or environmentally unfriendly, or not decomposing to give toxic, harmful and/or environmental unfriendly compounds during storage of said formulations over time.

Anti-corrosion formulations with storage stability


An electrically programmable memory including: an array of a plurality of memory cells arranged accordingly to a NAND architecture, said memory cells grouped into a plurality of memory blocks and each memory block including a plurality of memory pages; means for receiving an address corresponding to a respective memory block; selecting means for selecting the addressed memory block; and means for detecting a failure of the addressed memory block, wherein the means for detecting a failure includes: a plurality of registers, each register corresponding to a respective memory block and storing an indication of the failure of the respective memory block; and means for reading the register corresponding to the addressed memory block in response to the receiving of the address, and wherein the programmable memory further includes at least one redundant memory block of memory cells including a plurality of redundant memory pages, the selecting means selecting the at least one redundant memory block in place of the addressed memory block in response to the reading of the indication of the failure.

Non-volatile memories are commonly used in several applications when the data stored in the memory need to be preserved even in absence of power supply. Within the class of non-volatile memories, electrically programmable (and erasable) memories, such as flash memories, have become very popular in applications in which the data to be stored are not immutable (as it might be case of, e.g., a consolidated code for a microprocessor), being instead necessary from time to time to store new data, or to update the data already stored. Examples of such applications include memory cards of the type used for example in digital cameras.
Typically, the memory includes an arrangement of memory cells, disposed for example in rows and columns, so as to form a matrix. Depending on the way the memory cells in the matrix are interconnected, a so-called NAND architecture for the flash memories can be identified. Roughly speaking, in a NAND architecture, groups of memory cells of a same matrix column are serially interconnected so as to form respective strings, which strings are then connected in parallel to each other to a same bit line. NAND flash memories are compact (a low number of contacts in the matrix are required), and they are suited for applications such as file storage.
In the NAND architecture, the memory space is ideally partitioned into a plurality of memory pages, each page corresponding to a group of memory cells that, in operation, are read or written simultaneously, i.e. in parallel to each other. The number of memory cells in each group determines the size (i.e., the number of bits) of the memory page. Nowadays, memory pages of 512 Bytes are rather typical, but larger memory pages are also encountered, for example of 2 KBytes.
The memory space is further logically partitioned into a plurality of memory blocks or sectors, each memory block including a plurality of memory pages that, in operation, are erased simultaneously.
Before shipping, each NAND memory undergoes a testing phase in which some invalid memory blocks, i.e. containing invalid data bits not repairable, can be found. The invalid memory blocks (in jargon, referred to as "bad" blocks) are "marked" before utilization by programming a number of memory cells inside each bad block with a predetermined string of bits.
In addition, during the lifetime of the NAND memories (typically, of about ten years), a percentage of the initially valid memory blocks can become invalid after having endured cycles of erase or write operations (typically, the manufactures guarantee that at most 2% of the total number of the memory blocks may become bad during the expected lifetime).
Because the bad blocks are randomly scattered throughout the NAND memories, it is often necessary to map them so that they are not used, i.e. not addressed in either read or program.
In solutions known in the art, an external device that performs operations on the NAND memory, such as a microprocessor or a microcontroller, preliminarily scans the NAND memory for locating the bad blocks. The external device creates, stores, and manages a mapping, in terms of the memory addresses, of the NAND memory particularly of the bad blocks, using for example an additional non-volatile memory external to the NAND memory. Typically, the external memory is a Content Addressable Memory, and before any operation, the external device compares the memory address to be provided to the NAND memory with the mapping stored in the CAM; then, the external device discards and substitutes invalid memory addresses.
As a consequence, the managing of the operations to be performed on the NAND memory is greatly complicated, mainly because the managing of the bad blocks internal to the NAND memory is not transparent to the external user.
Furthermore, it has to be considered that finding bad blocks in a NAND memory implies an inevitable reduction of its storage capability, which contrasts with the increasing request for memories with greater and greater sizes.


A wheel guard system may include a wheel guard located on an upper portion of a tire; and a deflector to be folded to enter into and to be built in the wheel guard. The deflector may be unfolded to get out of the wheel guard and form tire alignment for shielding a whole tire width. In particular, the deflector is provided with a speed rib rotated by a motor, and the motor may fold or unfold the speed rib in a rotation direction of the motor.

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Recently, demand for improved fuel economy of a vehicle to cope with exhaust gas regulations that are gradually strengthened has been more intensified, and as countermeasures for this, attempts to improve aerodynamic characteristics (e.g., vehicle drag) of the vehicle have been regarded as more important.
Through this, technology to further heighten the fuel economy improvement rate has been strengthened through improvement of a vehicle underbody design in addition to a streamlined external design. This is because the resistance of the underbody and wheel/tire portion holds about 45% of the resistance of an upper part of a vehicle on the assumption that the whole vehicle drag is set to 100%.
As an example, an underbody aerodynamic improvement device includes a basic normal device, such as bumper rib, air dam, or wheel deflector, as an aerodynamic item for seeking flow improvement of the underbody and tire portion, and has been further developed as an active device capable of performing size adjustment as an aerodynamic item for solving restrictions of the normal body.
In particular, a size adjustment type underbody aerodynamic improvement device can change its shape to suit road conditions, and thus it is possible to heighten application of ground clearance specifications of the vehicle and to prevent interference problems that may occur on the bumper rib, air dam, or wheel deflector during driving on a speed bump or an uneven road.
Accordingly, since the underbody aerodynamic improvement device is applied to the vehicle as the normal device or the active device, the fuel efficiency can be improved by reducing the resistance of the underbody and wheel/tire portion which accounts for about 45% of the whole vehicle drag.
However, we have discovered that although the active device of the underbody aerodynamic improvement device has the advantages of providing size variations as compared with the size fixing type normal device, the size change of the active device is limited to in a vertical direction (i.e., ground clearance adjustment direction or vehicle height direction).
In addition, we have found that the vertical adjustment type active device has the drawbacks in that it is difficult to sufficiently secure the tire alignment with respect to a bumper having an enlarged side-surface curvature in bumper design (i.e., bumper side curvature), and such insufficient tire alignment undermines the aerodynamic effect for the underbody and wheel/tire portion.

Rotary shielding type wheel guard system and vehicle applying the same


Disclosed is a method and circuit for generating an average binary code from at least two input binary codes. The circuit may be employed in an integrated circuit having first and second circuits for generating binary codes am-1:0 and bm-1:0, respectively. In one embodiment, the circuit asynchronously generates a binary code cm-1:0 representing an average of the binary codes am-1:0 and bm-1:0 generated by the first and second circuits, respectively.

Integrated circuits including microprocessors often contain sub-circuits that generate multibit binary codes for controlling other sub-circuits within the integrated circuit. Often times, these integrated circuits require the averaging of two or more of the multibit binary codes, the result of which is used to control another sub-circuit. Typically, an adder sub-circuit and a divider sub-circuit operating together perform the function of averaging binary codes.
FIG. 1 illustrates relevant components of an integrated circuit 10 in block diagram form. Integrated circuit 10 includes sub-circuits 12-20. More particularly integrated circuit 10 includes first and second code generation sub-circuits 12 and 14, having outputs coupled to a pair of inputs of average code generation sub-circuit 16. Lastly integrated circuit 10 includes a sub-circuit 20 having an input which is coupled to the output of average code generation sub-circuit 16. For purposes of explanation, the term coupled circuits means that two circuits or sub-circuits that are directly or indirectly coupled together. For example, first code generation sub-circuit 12 is coupled to sub-circuit 20 although coupled via average code generation sub-circuit 16.
Average code generation sub-circuit 16 operates upon binary codes am-1:0 and bm-1:0. More particularly, average code generation circuit generates an average binary code cm-1:0 which represents the average of binary codes am-1:0 and bm-1:0. Average code generation sub-circuit 16 is a synchronous circuit and operates as a function of a clock signal (CLK) received thereby. In other words, average code generation sub-circuit 16 generates binary code cm-1:0 upon a falling or rising edge of the clock signal CLK. It is noted that first and second code generation circuits 12 and 14 are also shown to be synchronous sub-circuits. Average binary code cm-1:0 is provided to sub-circuit 20 which in turn performs some function in response to receiving cm-1:0.
FIG. 2 illustrates, in block diagram form, the relevant components of average code generation sub-circuit 16 of FIG. 1. More particularly, average code generation sub-circuit shown 16 in FIG. 2 includes an adder sub-circuit 22 coupled to a divider sub-circuit 24. The adder and divider sub-circuits 22 and 24, respectively, are shown as synchronous circuits in that they operate as a function of the clock signal CLK provided thereto. Adder sub-circuit 22 receives binary codes am-1:0 and bm-1:0 from first and second code generations sub-circuits 12 and 14, respectively. In response, adder sub-circuit 22 generates c′m-1:0 which represents an addition of binary codes am-1:0 and bm-1:0. Divider sub-circuit 24 operates to divide c′m-1:0 by two to generate average binary code cm-1:0.
One goal in integrated circuit design is to reduce the total substrate area occupied by the integrated circuit. Unfortunately, the adder and divider sub-circuits 22 and 24 may occupy a substantial area of the substrate upon which integrated circuit 10 is formed. Another goal in integrated circuit design is to reduce the complexity of sub-circuits. The adder and divider sub-circuits 22 and 24 are generally complex (i.e., they consist of a large number of interconnected gates) and require substantial design effort to implement and verify. Still yet another goal in integrated circuit design is to increase the speed at which the integrated circuit or sub-circuits thereof operate. Adder and divider circuits 22 and 24 are synchronous. A certain amount of time delay exists between generation of the average binary code cm-1:0 from the input binary codes am-1:0 and bm-1:0. This time delay is dependent upon the frequency of the clock signal CLK provided to adder and divider sub-circuits 22 and 24.


The present invention is directed to the modification of reserve polysaccharides in plants. Specifically, it has been found that host plants can be successfully transformed with a nucleic acid sequence capable of expressing a chimeric reserve polysaccharide modification enzyme gene sequence which will synthesize novel reserve polysaccharides in plants or convert the transformed plant's endogenous starch reserves to novel starch degradation products.

In the animal kingdom, nonvascular plants, fungi, yeast and bacteria, the primary reserve polysaccharide is glycogen. Glycogen is a D-glucose polysaccharide containing linear molecules with .alpha.-1,4 glycosyl linkages and is branched via .alpha.-1,6 glycosyl linkages. Although glycogen is analogous to starch from a linkage comparison, glycogen exhibits a different chain length and degree of polymerization. In bacteria, for example, the .alpha.-1,6 glycosyl linkages constitute only approximately 10% of the total linkages, indicating that the majority of the glycogen polymer resides as linear glucose units.
In vascular plants, reserve polysaccharides are stored in roots, tubers and seeds in the form of starch. Starch, a complex polymer of D-glucose, consists of a mixture of linear chain (amylose) and branched chain (amylopectin) glucans. Starches isolated from different plants are found to have distinct proportions of amylose. Typically, amylose comprises from about 10-25% of plant starch, the remainder being the branched polymer amylopectin. Amylopectin contains low molecular weight chains and high molecular weight chains, with the low molecular weight chains ranging from 5-30 glucose units and the high molecular weight chains from 30-100 or more. The ratio of amylose/amylopectin and the distribution of low molecular weight to high molecular weight chains in the amylopectin fraction are known to affect the properties, such as thermal stabilization, retrogradation, and viscosity, and therefore the utility of starch. The highest published low m.w./high m.w. chain ratios (on a weight basis) in amylopectin are 3.9/1 for waxy corn starch, which has unique properties. Additionally, duwx, which has slightly more branch points than waxy, also has further unique properties.
In addition, starches from different plants or plant parts often have different properties. For example, potato starch has different properties than other starches, some of which may be due to the presence of phosphate groups. In some plant species, mutants have been identified which have altered contents of amylose and amylopectin. Mutations that affect the activity of starch-branching enzyme in peas, for example, result in seeds having less starch and a lower proportion of amylopectin. Also, mutations in the waxy locus of maize, which encodes a starch granule bound starch synthase, result in plants which produce amylopectin exclusively. Similarly, a potato mutant has been identified whose starch is amylose-free (Hovenkamp-Hermelink et al. Theor. Appl. Genet. (1987) 75:217-221). It has been found that varying the degree of starch branching can confer desirable physical properties; other changes in the characteristics of native starch could result in the production of polymers with new applications.
Cyclodextrins are the products of enzymatic starch degradation by a class of amylases termed cyclodextrin glycosyltransferase (CGT) enzymes. The family of cyclodextrins contains three major and several minor cyclic oligosaccharides which are composed of a number of homogenous cyclic .alpha.-1,4-linked glucopyranose units. The cyclodextrin having six glucopyranose units is termed .alpha.-cyclodextrin (also know as Schardinger's .alpha.-dextrin, cyclomaltohexaose, cyclohexaglucan, cyclohexaamylose, .alpha.-CD, ACD and C6A). The seven unit cyclodextrin is termed .beta.-cyclodextrin (also known as Schardinger's .beta.-dextrin, cyclomaltoheptaose, cycloheptaglucan, .beta.-CD, BCD and C7A). The eight unit cyclodextrin is termed .gamma.-cyclodextrin (also known as Schardinger's .gamma.-dextrin, cyclomaltooctaose, cyclooctaglucan, cyclooctaamylose, .gamma.-CD, GCD and C8A).
The cyclic nature of cyclodextrins allows them to function as clathrates (inclusion complexes) in which a guest molecule is enclosed in the hydrophobic cavity of the cyclodextrin host without resort to primary valence forces. Thus, the components are bound as a consequence of geometric factors, and the presence of one component does not significantly affect the structure of the other component. Complexing a hydrophobic compound with cyclodextrin increases the stability and solubility of the hydrophobic compound. Applications of this phenomena have been found in many fields including pharmaceuticals, foods cosmetics and pesticides.
In pharmaceutical applications, complexing a drug with cyclodextrins for oral delivery can have many advantages. Among the benefits are the transformation of liquids into solids which can be formed into tablets, stabilization of drugs against volatilization and oxidation, reduction of bad taste or smell, improvement in the rate of dissolution of poorly soluble drugs and increases in blood levels of poorly water soluble drugs (Pitha, in Controlled Drug Delivery, Bruck, ed. Vol. 1, p. 125, (1983) CRC Press). From the limited research done on parenteral administration of cyclodextrin-complexed drugs, some of the same advantages found for oral delivery can also be observed. The undesirable side effects of drugs can be reduced with complexation with cyclodextrins. Such side affects include gastric irritation from oral delivery, local irritation and hemorrhagic areas from intramuscular injection, and local irritation from eye-drops (Szejtli, J., Cyclodextrin Technology, Kluwer Academic Publications, Boston (1988), pp. 186-306).
The addition of cyclodextrins to food products or cosmetics can also have many effects. In spices, food flavoring or perfume fragrances, cyclodextrins protect against oxidation, volatility, and degradation by heat or light (Hashimoto, H., "Application of Cyclodextrins to Food, Toiletries and Other Products in Japan," in Proceedings of the Fourth International Symposium of Cyclodextrins, O. Huber and J. Szejtli, eds. (1988) pp. 533-543). Cyclodextrins can also eliminate or reduce undesirable smells or tastes, and modify food or cosmetic textures.
Complexing pesticides with cyclodextrins can increase the bioavailability of poorly wettable or slightly soluble substances, and transform volatile liquids or sublimable solids into stable solid powders (Szejtli, J. (1988) supra at pp. 335-364; U.S. Pat. No. 4,923,853). Pesticides which are sensitive to light, heat or oxygen degradation can be stabilized by complexing with cyclodextrins.
Currently, production of cyclodextrins begins with the cultivation of an appropriate microorganism, e.g., Bacillus macerans, and separation, purification and concentration of the amylase enzyme. The enzyme is then used to convert a starch substrate to a mixture of cyclic and acyclic dextrins. Subsequent separation and purification of cyclodextrins is then required. The bacterial strain from which the enzyme is isolated and the length of time the starch conversion is allowed to progress determines the predominant form of cyclodextrin produced. Manufactures of .alpha.-cyclodextrins attempt to manipulate the reaction to preferentially make the specific cyclodextrin, however, the process is not easily controlled, and a mixture of cyclodextrins is obtained. At the present time .beta.-cyclodextrin is the most widely commercialized form of cyclodextrin because the .beta.-form is much cheaper to produce than the .alpha.- or .gamma.-cyclodextrins.
In 1987, the U.S. market for cyclodextrins was predicted to reach $50 million per year within 2 years; that figure would double if the U.S. Food and Drug Administration approved the use of cyclodextrins in food (Seltzer, R., Chem. Eng. News, (May 1987) pp. 24-25). The world market is estimated to be twice the U.S. figure (Szejtli, J. (1988) supra at p. viii). The potential U.S. market for cyclodextrins has been predicted to reach as high as $245 million per year (Anon., Bioproc. Technol., Nov. 1987). There is potentially a large market waiting to be tapped if the cost of cyclodextrins could be lowered through alternative production methods.
With the development of genetic engineering techniques, it is now possible to transfer genes from a variety of organism into the genome of a large number of different plant species. This process is preferable to plant breeding techniques whereby genes can only be transferred from one plant in a species to another plant in the same or a closely related species. It would thus be desirable to develop plant varieties through genetic engineering, which have increased capacity for starch synthesis, altered amylose/amylopectin ratios, altered distribution of low to high molecular weight chains in the amylopectin fraction and also starches with novel molecular weight characteristics. In this manner, useful starches with a variety of viscosity or texture differences may be obtained.
In addition, recognizing the disadvantages of bacterial-derived CGT-mediated cyclodextrin production, it is considered desirable to produce cyclodextrins where CGT is the expression product of a recombinant gene transferred into a plant host. In this method, generically known as molecular farming, plants are transformed with a structural gene of interest and the product extracted and purified from a harvested field of the transgenic plants. For example, human serum albumin has been produced in transgenic tobacco and potato (Sijmons, P. C. et al., Bio/Technology (1990) 8:217-221).
Extending the idea of molecular farming to cyclodextrins provides a means to lower production costs. One particularly desirable host plant for such transformation is potato because of the large amount of starch production in potato tubers. A typical tuber contains approximately 16% of its fresh weight as starch (Burton, W. G., The Potato (1966) 3rd Edition, Longman Scientific and Technical Publications, England, p. 361). Transformation of potato plants with the bacterial CGT structural gene linked to a tuber-specific promoter and a leader directing the enzyme, for example, to the amyloplast, provides a means to produce large quantities of cyclodextrins in tubers.
To this end, nucleic acid sequences which encode glycogen biosynthetic or degradative enzymes are desirable for study and manipulation of the starch biosynthetic pathway. In particular, these enzymes may be expressed in plant cells using plant genetic engineering techniques and targeted to a plastid where starch synthesis occurs. It was therefore considered desirable to apply recombinant deoxyribonucleic acid (rDNA) and related technologies to provide for modified reserve polysaccharides in transgenic plants.
Proceeding from the seminal work of Cohen & Boyer, U.S. Pat. No. 4,237,224, rDNA technology has become available to provide novel DNA sequences and to produce heterologous proteins in transformed cell cultures. In general, the joining of DNA from different organisms relies on the excision of DNA sequences using restriction endonucleases. These enzymes are used to cut donor DNA at very specific locations, resulting in gene fragments which contain the DNA sequences of interest. Alternatively, structural genes coding for desired peptides and regulatory control sequences of interest can now be produced synthetically to form such DNA fragments.
These DNA fragments usually contain short single-stranded tails at each end, termed "sticky-ends". These sticky-ended fragments can then be ligated to complementary fragments in expression vehicles which have been prepared, e.g., by digestion with the same restriction endonucleases. Having created an expression vector which contains the structural gene of interest in proper orientation with the control elements, one can use this vector to transform host cells and express the desired gene product with the cellular machinery available. Recombinant DNA technology provides the opportunity for modifying plants to allow the expression of desirable enzymes in planta.
However, while the general methods are easy to summarize, the construction of an expression vector containing a desired structural gene is a difficult process and the successful expression of the desired gene product in significant amounts while retaining its biological activity is not readily predictable. Frequently, bacterial-derived gene products are not biologically active when expressed in plant systems.
To successfully modify plants using rDNA, one must usually modify the naturally occurring plant cell in a manner in which the cell can be used to generate a plant which retains the modification. Even in successful cases, it is often essential that the modification be subject to regulation. That is, it is desirable that the particular gene be regulated as to the differentiation of the cells and maturation of the plant tissue. In the case of glycogen synthase, ADP-glucose pyrophosphorylase and/or cyclodextrin glycosyltransferase, it is also important that the modification be performed at a site where the product will be directed to contact the reserve polysaccharide regions of the modified plant. Thus, genetic engineering of plants with rDNA presents substantially increased degrees of difficulty.
In addition, the need to regenerate plants from the modified cells greatly extends the period of time before one can establish the utility of the genetic construct. It is also important to establish that the particular constructs will be useful in a variety of different plant species. Furthermore, one may wish to localize the expression of the particular construct in specific sites and it is desirable that the genetically modified plant retain the modification through a number of generations.
Relevant Literature
The structural genes encoding the E. coli glycogen biosynthetic enzymes have been cloned (Okita, et al. (1981) J. Biol. Chem. 256:6944-6952) and their nucleic acid sequences determined (Preiss, J. (1984) Ann. Rev. Microbiol. 38:419-458; Kumar et al. (1986) J. Biol. Chem. 261:16256-16259). Genes encoding mammalian glycogen synthases have also been cloned and their nucleic acid sequences determined (Browner, et al. Proc. Nat. Acad. Sci. (1989) 86:1443-1447; Bai, et al., J. Biol Chem. (1990) 265:7843-7848).


An optical system including a light-guide optical element (LOE) with a first set of mutually-parallel, partially-reflecting surfaces and a second set of mutually-parallel, partially-reflecting surfaces at a different orientation from the first set. Both sets of partially-reflecting surfaces are located between a set of mutually-parallel major external surfaces. Image illumination introduced at a coupling-in location propagates along the LOE, is redirected by the first set of partially-reflecting surfaces towards the second set of partially-reflecting surfaces, where it is coupled out towards the eye of the user. The first set of partially-reflecting surfaces are implemented as partial surfaces located where needed for filling an eye-motion box with the required image. Additionally, or alternatively, spacing of the first set of partially-reflecting surfaces is varied across a first region of the LOE. Additional features relate to relative orientations of the projector and partially reflecting surfaces to improve compactness and achieve various adjustments.

The present invention relates to optical systems and, in particular, it concerns an optical system including a light-guide optical element (LOE) for achieving optical aperture expansion.
Many near-eye display systems include a transparent light-guide optical element (LOE) or "waveguide" placed before the eye of the user, which conveys an image within the LOE by internal reflection and then couples out the image by a suitable output coupling mechanism towards the eye of the user. The output coupling mechanism may be based on embedded partial reflectors or "facets", or may employ a diffractive pattern. The description below will refer primarily to a facet-based coupling-out arrangement, but it should be appreciated that various features of the invention are also applicable to diffractive arrangements.

Optical systems including light-guide optical elements with two-dimensional expansion


Fluorinated naphthalene derivatives of the formula (I)

This application was filed pursuant to 35 U.S.C. 371 from international application no. PCT/EP98/06938, filed Mar. 11, 1998, which in turn claims priority to German Application Nos. 197 48 432.8, 197 48 440.9, 197 48 438.7 and 19748 435.2, all filed Nov. 3, 1997.
In addition to nematic and cholesteric liquid crystals, chiral tilted smectic (ferroelectric) liquid crystals have also been used recently in commercial display devices.
Clark and Lagerwall have been able to show that the use of ferroelectric liquid crystals (FLCs) in very thin cells results in opto-electrical switching or display elements which have response times which are faster by a factor of up to 1000 compared with conventional TN (xe2x80x9ctwisted nematicxe2x80x9d) cells (see, for example, EP-A 0 032 362). On the basis of this and other favorable properties, for example the possibility of bistable switching and the fact that the viewing angle is virtually independent of the contrast, FLCs are fundamentally highly suitable for areas of application such as computer displays.
The use of FLCs in electro-optical or fully optical components requires either compounds which form tilted or orthogonal smectic phases and are themselves optically active, or the induction of ferroelectric smectic phases by doping compounds which, although forming such smectic phases, are not themselves optically active, with optically active compounds. The desired phase should be stable over the broadest possible temperature range.
In order to achieve good contrast in electro-optical components, a uniform planar alignment of the liquid crystals is necessary. Good alignment in the SA and SC phase can be achieved, for example, if the phase sequence of the liquid-crystal mixture is, with decreasing temperature:
isotropicxe2x86x92N*xe2x86x92SAxe2x86x92S*C
The prerequisite is that the pitch of the helix in the N* phase is very large (greater than 10 xcexcm) or, even better, is fully compensated (see, for example, T. Matsumoto et al, Proc. of the 6th Int. Display Research Conf., Japan Display, Sep. 30-Oct. 2, 1986, Tokyo, Japan, pp. 468-470; M. Murakami et al., ibid. pp. 344-347). This is achieved by mixing the chiral liquid-crystal mixture having, for example, a left-handed helix in the N* phase with one or more optically active dopants which induce a right-handed helix, in such amounts that the helix is compensated.
Use of Clark and Lagerwall""s SSFLCD (surface-stabilized ferroelectric liquid-crystal display) effect for uniform, planar alignment furthermore requires that the pitch in the smectic C* phase is significantly greater than the thickness of the display element (Mol. Cryst. Liq. Cryst. 1983, 94, 213 and 1984, 114, 151).
The optical response time xcfx84 [xcexcs] of ferroelectric liquid-crystal systems, which should be as short as possible, depends on the rotational viscosity of the system xcex3 [mPas], the spontaneous polarization Ps [nC/cm2] and the electric field strength E [V/m], in accordance with the equation   τ  ∼      γ                  P        s            ·      E
Since the field strength E is determined by the electrode separation in the electro-optical component and by the applied voltage, the ferroelectric display medium must have low viscosity and high spontaneous polarization in order to achieve a short response time.
Finally, in addition to thermal, chemical and photochemical stability, a low optical anisotropy xcex94n and a low positive or preferably negative dielectric anisotropy xcex94xcex5 are required (see, for example, S. T. Lagerwall et al., xe2x80x9cFerroelectric Liquid Crystals for Displaysxe2x80x9d, SID Symposium, October Meeting 1985, San Diego, Calif., USA).
The totality of these requirements can only be achieved by means of mixtures of a plurality of components. The base (or matrix) used preferably comprises compounds which if possible themselves already have the desired phase sequence Ixe2x86x92Nxe2x86x92SAxe2x86x92SC. Further components of the mixture are frequently added in order to lower the melting point and to broaden the SC and usually also the N phase, to induce optical activity, for pitch compensation and to match the optical and dielectric anisotropies; however, the rotational viscosity, for example, should if possible not be increased.
Ferroelectric liquid-crystal displays can also be operated by utilizing the DHF (distorted helix formation) effect or the PSFLCD effect (pitch-stabilized ferroelectric liquid-crystal display, also known as SBF=short pitch bistable ferroelectric effect). The DHF effect has been described by B. I. Ostrovski in Advances in Liquid Crystal Research and Applications, Oxford/Budapest, 1980, 469 ff., and the PSFLCD effect is described in DE-A 39 20 625 and EP-A 0 405 346. In contrast to the SSFLCD effect, utilization of these effects requires a liquid-crystalline material having a short SC pitch.
3,4-Difluorotetralin derivatives for use in liquid-crystal mixtures are disclosed, for example, in DE-A 19522145. Tetrafluorotetralin derivatives for use in liquid-crystal mixtures are disclosed, for example, in DE-A 19522152. Trifluoronaphthalene derivatives for use in liquid-crystal mixtures are disclosed, for example, in DE-A 19522195. Difluoronaphthalene derivatives for use in liquid-crystal mixtures are disclosed, for example, in DE-A 19522167.
However, since the development, in particular of ferroelectric liquid-crystal mixtures, can in no way be regarded as complete, the manufacturers of displays are interested in a very wide variety of components for mixtures. Another reason for this is that only the interaction of the liquid-crystalline mixtures with the individual components of the display device or of the cells (for example the alignment layer) allows conclusions to be drawn on the quality of the liquid-crystalline mixtures too.
The object of the present invention was therefore to provide novel compounds which, in liquid-crystalline mixtures, are suitable for improving the property profile of these mixtures.
Surprisingly, it has been found that fluorinated naphthalene derivatives of the formula (I) are particularly suitable for use in liquid-crystal mixtures. These are, in particular, 6,7difluoro-1,2,3,4-tetrahydronaphthalene derivatives, 1,1,6,7-tetrafluoro-1,2,3,4-tetrahydronaphthalene derivatives, 1,6,7-trifluoronaphthalene derivatives and 2,3-difluoronaphthalene derivatives of the formula (I).
6,7-Difluoro-3,4-dihydro-2H-naphthalen-1-one is disclosed, for example, in Synth. Commun. 1991, 21, 981-7, but there is no mention therein of this molecule or its derivatives being suitable as part of a component of liquid-crystal mixtures.
The invention therefore relates to fluorinated naphthalene derivatives of the formula (I)
R1(xe2x80x94A1xe2x80x94M1)a(xe2x80x94A2xe2x80x94M2)bxe2x80x94Bxe2x80x94(xe2x80x94M3xe2x80x94A3)cxe2x80x94(M4xe2x80x94A4)dxe2x80x94R2xe2x80x83xe2x80x83(I)
where the symbols and indices are defined as follows:
group B is
xe2x80x83having the meaning
R1 and R2 are identical or different and are
a) hydrogen, xe2x80x94OCF3, xe2x80x94CF3, xe2x80x94CN, xe2x80x94F, xe2x80x94Cl, xe2x80x94OCHF2, xe2x80x94OCH2F, xe2x80x94CHF2 or xe2x80x94CH2F
b) a straight-chain or branched alkyl radical (with or without an asymmetrical carbon atom) having 1 to 20 carbon atoms, where
b1) one or more non-adjacent and non-terminal xe2x80x94CH2xe2x80x94 groups may be replaced by xe2x80x94Oxe2x80x94, xe2x80x94Sxe2x80x94, xe2x80x94COxe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94COxe2x80x94, xe2x80x94Oxe2x80x94COxe2x80x94Oxe2x80x94 or xe2x80x94Si(CH3)2xe2x80x94, and/or
b2) one or more xe2x80x94CH2xe2x80x94 groups may be replaced by xe2x80x94CHxe2x95x90CHxe2x80x94, xe2x80x94Cxe2x89xa1Cxe2x80x94, cyclopropane-1,2-diyl, 1,4-phenylene, 1,4-cyclohexylene or 1,3-cyclopentylene, and/or
b3) one or more H atoms may be replaced by F and/or Cl, and/or
b4) the terminal xe2x80x94CH3 group may be replaced by one of the following chiral groups (optically active or racemic):
with the proviso that at most one of the radicals R1 and R2 is hydrogen, xe2x80x94OCF3, xe2x80x94CF3, xe2x80x94CN, xe2x80x94F, xe2x80x94Cl, xe2x80x94OCHF2, xe2x80x94OCH2F, xe2x80x94CHF2 or xe2x80x94CH2F;
R3, R4, R5, R6 and R7 are identical or different and are
a) hydrogen
b) a straight-chain or branched alkyl radical (with or without an asymmetrical carbon atom) having 1 to 16 carbon atoms, where
b1) one or more non-adjacent and non-terminal xe2x80x94CH2xe2x80x94 groups may be replaced by xe2x80x94Oxe2x80x94, and/or
b2) one or two xe2x80x94CH2xe2x80x94 groups may be replaced by xe2x80x94CHxe2x95x90CHxe2x80x94,
c) R4 and R5 together may alternatively be xe2x80x94(CH2)4xe2x80x94 or xe2x80x94(CH2)5xe2x80x94 if they are bonded to an oxirane, dioxolane, tetrahydrofuran, tetrahydropyran, butyrolactone or valerolactone system;
M1, M2, M3 and M4 are identical or different and are xe2x80x94COxe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94COxe2x80x94, xe2x80x94COxe2x80x94Sxe2x80x94, xe2x80x94Sxe2x80x94COxe2x80x94, xe2x80x94CSxe2x80x94Oxe2x80x94, xe2x80x94CSxe2x80x94Sxe2x80x94, xe2x80x94Oxe2x80x94CSxe2x80x94, xe2x80x94Sxe2x80x94CSxe2x80x94, xe2x80x94CH2Oxe2x80x94, xe2x80x94Oxe2x80x94CH2xe2x80x94, xe2x80x94CH2xe2x80x94Sxe2x80x94, xe2x80x94Sxe2x80x94CH2xe2x80x94, xe2x80x94CHxe2x95x90CHxe2x80x94, xe2x80x94Cxe2x89xa1Cxe2x80x94, xe2x80x94CH2xe2x80x94CH2xe2x80x94COxe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94COxe2x80x94CH2xe2x80x94CH2xe2x80x94 or a single bond;
A1, A2, A3 and A4 are identical or different and are 1,4-phenylene, in which one or more H atoms may be replaced by F, Cl and/or CN, pyrazine-2,5-diyl, in which one or two H atoms may be replaced by F, Cl and/or CN, pyridazine-3,6-diyl, in which one or two H atoms may be replaced by F, Cl and/or CN, pyridine-2,5-diyl, in which one or more H atoms may be replaced by F, Cl and/or CN, pyrimidine-2,5-diyl, in which one or two H atoms may be replaced by F, Cl and/or CN, 1,4-cyclohexylene, in which one or two H atoms may be replaced by CN and/or CH3 and/or F, 1,3,4-thiadiazole-2,5-diyl, 1,3-dioxane-2,5-diyl, 1,3-dithiane-2,5-diyl, 1,3-thiazole-2,4-diyl, in which one H atom may be replaced by F, Cl and/or CN, 1,3-thiazole-2,5-diyl, in which one H atom may be replaced by F, Cl and/or CN, thiophene-2,4-diyl, in which one H atom may be replaced by F, Cl and/or CN, thiophene-2,5-diyl, in which one or two H atoms may be replaced by F, Cl and/or CN, naphthalene-2,6-diyl, in which one or more H atoms may be replaced by F, Cl and/or CN, or 1-alkyl-1-silacyclohexane-1,4-diyl;
a, b, c and d are 0 or 1; with the proviso that the compound of the formula (I) does not contain more than four, preferably at least two, five- or multi-membered ring systems.
The provision of compounds of the formula (I) very generally considerably broadens the range of liquid-crystalline substances which are suitable, from various applicational points of view, for the preparation of liquid-crystalline mixtures.
In this connection, the compounds of the formula (I) have a broad range of applications. Depending on the choice of substituents, they can be used as base materials of which liquid-crystalline phases are predominantly composed; however it is also possible to add compounds of the formula (I) to liquid-crystalline base materials from other classes of compound in order, for example, to modify the dielectric and/or optical anisotropy of a dielectric of this type and/or to optimize its threshold voltage and/or its viscosity.
The compounds of the formula (I) are particularly suitable, even when added in small amounts, for influencing the dielectric anisotropy (xcex94xcex5) toward more highly negative values.
The compounds of the formula (I) according to the invention are particularly suitable for use in nematic and smectic liquid-crystal mixtures, in the case of nematic mixtures in particular for active matrix displays (AM-LCDs) (see, for example, C. Prince, Seminar Lecture Notes, Volume I, p. M-3/3-M-22, SID International Symposium 1997, B. B. Bahadur, Liquid Crystal Applications and Uses, Vol. 1, p. 410, World Scientific Publishing, 1990, E. Lxc3xcder, Recent Progress of AM LCD""s, Proceedings of the 15th International Display Research Conference, 1995, p. 9-12) and in-plane switching displays (IPS-LCDs), in the case of smectic liquid-crystal mixtures for ECB displays (electrically controlled birefringence), for electroclinic displays and chiral tilted smectic (ferroelectric) displays. The compounds of the formula (I) according to the invention are particularly suitable for use in FLC mixtures for ferroelectric switching and/or display devices which are operated in inverse mode.
The symbols and indices in the formula (I) preferably have the following meanings:
R1 and R2 are preferably identical or different and are
a) hydrogen,
b) a straight-chain or branched alkyl radical (with or without an asymmetrical carbon atom) having 1 to 18 carbon atoms, where
b1) one or more non-adjacent and non-terminal xe2x80x94CH2xe2x80x94 groups may be replaced by xe2x80x94Oxe2x80x94, xe2x80x94COxe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94COxe2x80x94, xe2x80x94Oxe2x80x94COxe2x80x94Oxe2x80x94or xe2x80x94Si(CH3)2xe2x80x94, and/or
b2) one xe2x80x94CH2xe2x80x94 group may be replaced by cyclopropane-1,2-diyl, 1,4-phenylene or trans-1,4-cyclohexylene, and/or
b3) one or more H atoms may be replaced by F, and/or
b4) the terminal CH3 group may be replaced by one of the following chiral groups (optically active or racemic):
with the proviso that at most one of the radicals R1 and R2 is hydrogen.
R1 and R2 are particularly preferably identical or different and are
a) hydrogen,
b) a straight-chain or branched alkyl radical (with or without an asymmetrical carbon atom) having 1 to 16 carbon atoms, where
b1) one or two non-adjacent and non-terminal xe2x80x94CH2xe2x80x94 groups may be replaced by xe2x80x94Oxe2x80x94, xe2x80x94COxe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94COxe2x80x94, xe2x80x94Oxe2x80x94COxe2x80x94Oxe2x80x94or xe2x80x94Si(CH3)2xe2x80x94, and/or
b2) one xe2x80x94CH2xe2x80x94 group may be replaced by 1,4-phenylene or trans-1,4-cyclohexylene, and/or
b3) one or more H atoms may be replaced by F, and/or
b4) the terminal CH3 group may be replaced by one of the following chiral groups (optically active or racemic):
with the proviso that at most one of the radicals R1 and R2 is hydrogen.
R3, R4, R5, R6 and R7 are preferably identical or different and are
a) hydrogen
b) a straight-chain or branched alkyl radical (with or without an asymmetrical carbon atom) having 1 to 14 carbon atoms, where
b1) one or two non-adjacent and non-terminal xe2x80x94CH2xe2x80x94 groups may be replaced by xe2x80x94Oxe2x80x94, and/or
b2) one xe2x80x94CH2xe2x80x94 group may be replaced by xe2x80x94CHxe2x95x90CHxe2x80x94,
c) R4 and R5 together may alternatively be xe2x80x94(CH2)4xe2x80x94 or xe2x80x94(CH2)5xe2x80x94 if they are bonded to an oxirane, dioxolane, tetrahydrofuran, tetrahydropyran, butyrolactone or valerolactone system.
R3, R4, R5, R6 and R7 are particularly preferably identical or different and are
a) hydrogen
b) a straight-chain or branched alkyl radical (with or without an asymmetrical carbon atom) having 1 to 14 carbon atoms, where
b1) one non-terminal xe2x80x94CH2xe2x80x94 group may be replaced by xe2x80x94Oxe2x80x94,
c) R4 and R5 together may alternatively be xe2x80x94(CH2)4xe2x80x94 or xe2x80x94(CH2)5xe2x80x94 if they are bonded to an oxirane, dioxolane, tetrahydrofuran, tetrahydropyran, butyrolactone or valerolactone system.
M1, M2, M3 and M4 are preferably identical or different and are xe2x80x94COxe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94COxe2x80x94, xe2x80x94CH2xe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94CH2xe2x80x94, xe2x80x94CHxe2x95x90CHxe2x80x94, xe2x80x94Cxe2x89xa1Cxe2x80x94, xe2x80x94CH2xe2x80x94CH2xe2x80x94COxe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94COxe2x80x94CH2xe2x80x94CH2xe2x80x94 or a single bond.
M1, M2, M3 and M4 are particularly preferably identical or different and are xe2x80x94COxe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94COxe2x80x94, xe2x80x94CH2xe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94CH2xe2x80x94 or a single bond.
A1, A2, A3 and A4 are preferably identical or different and are 1,4-phenylene, in which one or two H atoms may be replaced by F and/or CN, pyridine-2,5-diyl, in which one or two H atoms may be replaced by F and/or CN, pyrimidine-2,5-diyl, in which one or two H atoms may be replaced by F, trans-1,4-cyclohexylene, in which one or two H atoms may be replaced by CN and/or CH3 and/or F, 1,3,4-thiadiazole-2,5-diyl, 1,3-dioxane-2,5-diyl, 1,3-thiazole-2,4-diyl, in which one H atom may be replaced by F and/or CN, 1,3-thiazole-2,5-diyl, in which one H atom may be replaced by F and/or CN, and thiophene-2,5-diyl, in which one or two H atoms may be replaced by F and/or CN.
A1, A2, A3 and A4 are particularly preferably identical or different and are 1,4-phenylene, in which one or two H atoms may be replaced by F, pyridine-2,5-diyl, in which one H atom may be replaced by F, pyrimidine-2,5-diyl, and trans-1,4-cyclohexylene, in which one or two H atoms may be replaced by CN and/or CH3 and/or F.
Very particularly preferred for 6,7-difluoro-1,2,3,4-tetrahydronaphthalene derivatives are the following compounds of the formulae (Ia) to (It):
in which R8and R9 are identical or different and are a straight-chain or branched alkyl chain having 1 to 19 carbon atoms, in which one or two hydrogen atoms may be replaced by F, and R10 and R11 are identical or different and are a straight-chain or branched alkyl or alkoxy chain having 1 to 20 or 1 to 19 carbon atoms respectively, in which one or two hydrogen atoms may be replaced by F.
Very particularly preferred for 1,1,6,7-tetrafluoro-1,2,3,4-tetrahydronaphthalene derivatives are the following compounds of the formulae (Ia) to (It):
in which R8 and R9 are identical or different and are a straight-chain or branched alkyl chain having 1 to 19 carbon atoms, in which one or two hydrogen atoms may be replaced by F, and R10 and R11 are identical or different and are a straight-chain or branched alkyl or alkoxy chain having 1 to 20 or 1 to 19 carbon atoms respectively, in which one or two hydrogen atoms may be replaced by F.
Very particularly preferred for 1,6,7-trifluoronaphthalene derivatives are the following compounds of the formulae (Ia) to (It):
in which R8 and R9 are identical or different and are a straight-chain or branched alkyl chain having 1 to 19 carbon atoms, in which one or two hydrogen atoms may be replaced by F, and R10 and R11 are identical or different and are a straight-chain or branched alkyl or alkoxy chain having 1 to 20 or 1 to 19 carbon atoms respectively, in which one or two hydrogen atoms may be replaced by F.
Very particularly preferred for 2,3-difluoronaphthalene derivatives are the following compounds of the formulae (Ia) to (It):
in which R8 and R9 are identical or different and are a straight-chain or branched alkyl chain having 1 to 19 carbon atoms, in which one or two hydrogen atoms may be replaced by F, and R10 and R11 are identical or different and are a straight-chain or branched alkyl or alkoxy chain having 1 to 20 or 1 to 19 carbon atoms respectively, in which one or two hydrogen atoms may be replaced by F.
The compounds according to the invention are prepared by methods known per se from the literature, as described in the standard works on organic synthesis, for example Houben-Weyl, Methoden der Organischen Chemie [Methods of Organic Chemistry], Georg-Thieme-Verlag, Stuttgart.
The preparation is carried out under reaction conditions which are known and suitable for said reactions. Use can also be made here of variants which are known per se, but are not mentioned here in great detail.
If desired, the starting materials can also be formed in situ by not isolating them from the reaction mixture, but instead immediately converting them further into compounds of the formula (I).
The following schemes show by way of example synthetic routes for the synthesis of 6,7-difluoro-3,4-dihydro-2H-naphthalen-1-one derivatives and further to compounds of the formula (I), although other processes are feasible and possible.
Scheme 1
a) analogously to: Rec. Chem. Prog. 1968, 28, 99
b) analogously to: Chem. Ber. 1992, 1865
c) analogously to: Liquid Crystals 1996, 21, 279
d) analogously to: Chem. Ber. 1992, 1865
Scheme 2
e) analogously to: Org. Prep. Proc. Int. 1980, 12, 13
f) analogously to: J. Org. Chem. 1975, 40, 574
Scheme 3
g) analogously to: J. Chem. Soc. 1976, 98, 8114
h) analogously to: J. Org. Chem. 1975, 40, 574
i) analogously to: J. Chem. Soc. 1954, 3569
Scheme 4
k) analogously to: Org. Prep. Proc. Int. 1980, 12, 13
m) analogously to: J. Chem. Soc. 1954, 3569
Scheme 5
n) analogously to: J. Chem. Soc. 1976, 98, 8114
o) analogously to: DE-A 44 15 881
p) analogously to: J. Chem. Soc. 1954, 3569
Scheme 6
q) analogously to: Liq. Cryst. 1997, 23, 69
r) analogously to: Liq. Cryst. 1997, 23, 69
s) analogously to: J. Chem. Soc. 1954, 3569
The Rx is identical to the group R1(xe2x80x94A1xe2x80x94M 1)a(xe2x80x94A2xe2x80x94M2)bxe2x80x94 or a suitable, optionally protected precursor thereof which can be converted into this group in later steps by methods known per se which are familiar to the person skilled in the art. The Ry is identical to the group (xe2x80x94M3xe2x80x94A3)c(xe2x80x94M4xe2x80x94A4)dxe2x80x94R2 or a suitable, optionally protected precursor thereof which can be converted into this group in later steps by methods known per se which are familiar to the person skilled in the art. The preparation is carried out under reaction conditions which are known and suitable for said reactions. Use may also be made here of variants which are known per se, but are not mentioned here in greater detail.
For example, reference may be made to DE-A 23 44 732, 24 50 088, 24 29 093, 25 02 94, 26 36 684, 27 01 591 and 27 52 975 for compounds containing 1,4-cyclohexylene and 1,4-phenylene groups; DE-A 26 41 724 for compounds containing pyrimidine-2,5-diyl groups; DE-A 40 26 223 and EP-A 03 91 203 for compounds containing pyrdine-2,5-diyl groups; DE-A 32 31 462 for compounds containing pyridazine-3,6-diyl groups; EP-A 309 514 for compounds containing 1,3,4-thiadiazole-2,5-diyl groups; WO-A 92/16500 for naphthalene-2,6-diyl groups; K. Seto et al., Journal of the Chemical Society, Chemical Communications 1988, 56, for dioxoborinane-2,5-diyl groups.
The preparation of disubstituted pyridines, disubstituted pyrazines, disubstituted pyrimidines and disubstituted pyridazines is also given, for example, in the corresponding volumes in the series xe2x80x9cThe Chemistry of Heterocyclic Compoundsxe2x80x9d by A. Weissberger and E. C. Taylor (Editors). Dioxane derivatives are advantageously prepared by reaction of a corresponding aldehyde (or a reactive derivative thereof) with a corresponding 1,3-diol (or a reactive derivative thereof), preferably in the presence of an inert solvent, such as benzene or toluene, and/or in the presence of a catalyst, for example a strong acid, such as sulfuric acid, benzenesulfonic acid or p-toluenesulfonic acid, at temperatures from about 20xc2x0 C. to about 150xc2x0 C., preferably from 80xc2x0 C. to 120xc2x0 C. Primarily suitable reactive derivatives of the starting materials are acetals.
Some of said aldehydes and 1,3-diols and reactive derivatives thereof are known and some can be prepared without difficulty by standard methods of organic chemistry from compounds known from the literature. For example, the aldehydes are obtainable by oxidation of corresponding alcohols or by reduction of nitrites or corresponding carboxylic acids or derivatives thereof, and the diols are obtainable by reduction of corresponding diesters.
Compounds in which an aromatic ring is substituted by at least one F atom can also be obtained from the corresponding diazonium salts by replacement of the diazonium group with a fluorine atom, for example by the methods of Balz and Schiemann.
As far as the linking of ring systems to one another is concerned, reference may be made, for example to the following:
N. Miyaura, T. Yanagai and A. Suzuki in Synthetic Communications 11 (1981), 513-519, DE-C 39 30 663, M. J. Sharp, W. Cheng, V. Snieckus in Tetrahedron Letters 28 (1987) 5093; G. W. Gray in J. Chem. Soc. Perkin Trans II 1989, 2041 and Mol. Cryst. Liq. Cryst. 172 (1989) 165, 204 (1991) 43 and 91; EP-A 0 449 015; WO-A 89/12039; WO-A 89/03821; EP-A 0 354 434 and EP-A 0 694 530 for the direct linking of aromatics and heteroaromatics; DE-A 32 01 721 for compounds containing xe2x80x94CH2CH2xe2x80x94 bridges, and Koji Seto et al. in Liquid Crystals 8 (1990) 861-870, for compounds containing xe2x80x94Cxe2x89xa1Cxe2x80x94 bridging members.
Esters of the formula (I) can also be obtained by esterification of corresponding carboxylic acids (or reactive derivatives thereof) using alcohols or phenols (or reactive derivatives thereof, by the DCC method (DCC=dicyclohexylcarbodiimide) or analogously to DE-A 44 27 198. The corresponding carboxylic acids and alcohols or phenols are known and can be prepared analogously to known processes.
Particularly suitable reactive derivatives of said carboxylic acids are the acid halides, especially the chlorides and bromides, furthermore the anhydrides, for example also mixed anhydrides, azides or esters, in particular alkyl esters having 1-4 carbon atoms in the alkyl group.
Particularly suitable reactive derivatives of said alcohols and phenols are the corresponding metal alkoxides or phenoxides, preferably of an alkali metal, such as sodium or potassium.
The esterification is advantageously carried out in the presence of an inert solvent. Particularly suitable solvents are ethers, such as diethyl ether, di-n-butyl ether, THF, dioxane or anisole, ketones, such as acetone, butanone or cyclohexanone, amides, such as DMF or hexamethylphosphoric triamide, hydrocarbons, such as benzene, toluene or xylene, halogenated hydrocarbons, such as tetrachloromethane, dichloromethane or tetrachloroethylene, and sulfoxides, such as dimethyl sulfoxide or sulfolane.
Ethers of the formula (I) are obtainable by etherification of corresponding hydroxyl compounds, preferably corresponding phenols, where the hydroxyl compound is advantageously first converted into a corresponding metal derivative, for example into the corresponding alkali metal alkoxide or alkali metal phenoxide by treatment with NaH, NaNH2, NaOH, KOH, Na2CO3 or K2CO3. This alkali metal compound can then be reacted with the corresponding alkyl halide, alkyl sulfonate or dialkyl sulfate, advantageously in an inert solvent, such as acetone, 1,2-dimethoxyethane, DMF or dimethyl sulfoxide, or alternatively with an excess of aqueous or aqueous-alcoholic NaOH or KOH, at temperatures from about 20xc2x0 to 100xc2x0 C.
Regarding the synthesis of specific radicals R1 and R2 reference may additionally be made, for example, to
EP-A 0 355 008 for compounds having silicon-containing side chains,
EP-A 0 292 954 for optically active compounds containing an oxirane ester unit,
EP-A 0 263 437 for optically active compounds containing an oxirane ether unit,
EP-A 0 361 272 for optically active compounds containing a dioxolane ester unit,
EP-A 0 351 746 for optically active compounds containing a dioxolane ether unit,
U.S. Pat. No. 5,051,506 for optically active compounds containing a 2,3-difluoroalkoxy unit,
U.S. Pat. No. 4,798,680 for optically active compounds containing a 2-fluoroalkoxy unit,
U.S. Pat. No. 4,855,429 for optically active compounds an xcex1-chlorocarboxyl unit,
EP-A 0 552 658 for compounds containing cyclohexylpropionyl radicals, and
EP-A 0 318 423 for compounds containing cyclopropyl groups in the side chain.
The invention also relates to the use of compounds of the formula (I) in liquid-crystal mixtures, preferably smectic and nematic mixtures, particularly preferably ferroelectric mixtures.
Particular preference is given to the use in ferroelectric liquid-crystal mixtures operated in inverse mode.
The invention furthermore relates to liquid-crystal mixtures, preferably smectic and nematic mixtures, particularly preferably ferroelectric and antiferroelectric mixtures, especially ferroelectric mixtures, comprising one or more compounds of the formula (I).
The smectic or nematic liquid-crystal mixtures according to the invention are preferably suitable for use in electro-optical displays, in the case of nematic mixtures particularly for xe2x80x9cactive matrix displaysxe2x80x9d and xe2x80x9cin-plane switching displaysxe2x80x9d (IPS-LCDs), in the case of smectic liquid-crystal mixtures for ECB (electrically controlled birefringence) displays, for electroclinic displays and chiral tilted smectic (ferroelectric and antiferroelectric) displays.
The liquid-crystal mixtures according to the invention generally comprise from 2 to 35 components, preferably from 2 to 25 components, particularly preferably from 2 to 20 components.
They generally comprise from 0.01 to 80% by weight, preferably from 0.1 to 60% by weight, particularly preferably from 0.1 to 30% by weight, of one or more, preferably 1 to 10, particularly preferably 1 to 5, very particularly preferably 1 to 3, of the compounds of the formula (I) according to the invention.
Further components of liquid-crystal mixtures comprising compounds of the formula (I) according to the invention are preferably selected from known compounds having smectic and/or nematic and/or cholesteric phases. These include, for example:
derivatives of phenylpyrimidine, as described, for example, in WO-A-86/06401 and U.S. Pat. No. 4,874,542,
meta-substituted aromatic compounds having a six-membered ring, as described, for example, in EP-A 0 578 054,
silicon compounds, as described, for example, in EP-A 0 355 008,
mesogenic compounds having only one side chain, as described, for example, in EP-A 0 541 081,
hydroquinone derivatives, as described, for example, in EP-A 0 603 786,
phenylbenzoates, as described, for example, in P. Keller, Ferroelectrics 58 (1984), 3, and J. W. Goodby et al., Liquid Crystals and Ordered Fluids, Vol. 4, New York, 1984, and
thiadiazoles, as described, for example, in EP-A 0 309 514.
Examples of suitable chiral, non-racemic dopants are the following:
optically active phenylbenzoates, as described, for example, in P. Keller, Ferroelectrics 58 (1984), 3, and J. W. Goodby et al., Liquid Crystals and Ordered Fluids, Vol. 4, New York, 1984,
optically active oxirane ethers, as described, for example, in EP-A 0 263 437 and WO-A 93/13093,
optically active oxirane esters, as described, for example, in EP-A 0 292 954,
optically active dioxolane ethers, as described, for example, in EP-A 0 351 746,
optically active dioxolane esters, as described, for example, in EP-A 0 361 272,
optically active tetrahydrofuran-2-carboxylic esters, as described, for example, in EP-A 0 355 561, and
optically active 2-fluoroalkyl ethers, as described, for example, in EP-A 0 237 007, EP-A 428 720 and U.S. Pat. No. 5,051,506.
Suitable further mixture components are listed, in particular, in international patent application PCT/EP 96103154, which is expressly incorporated herein by way of reference.
Preferred further components of FLC mixtures employed in inverse mode are the following:
phenanthrene derivatives of the formula (II)
fluoropyridines of the formula (III)
difluorophenylene derivatives of the formula (IV)
meta-substituted aromatic compounds of the formula (V)
4-cyanocyclohexyls of the formula (VI)
1,3,4-thiadiazoles of the formula (VII)
where the symbols and indices have the following meanings:
X1 and X2 are identical or different and are, independently of one another, CH, CF or N;
Y is F, CF3 or R;
R and Rxe2x80x2 are identical or different and are, independently of one another, as defined for R1 and R2 in the formula (I);
A and M are identical or different and are, independently of one another, as defined in the formula (I), and
a, b, c and d are identical or different and are, independently of one another, 0 or 1, with the proviso that the compounds can contain not more than four ring systems and, with the exception of the formula (II), must contain at least two ring systems.
The mixtures can in turn be used in electro-optical or fully optical elements, for example display elements, switching elements, light modulators, elements for image processing and/or signal processing or generally in the area of nonlinear optics.
The mixtures are furthermore suitable for field treatment, i.e. for operation in the quasi-bookshelf geometry (QBG) (see, for example, H. Rieger et al., SID 91 Digest (Anaheim), 1991, 396).
The ferroelectric mixtures according to the invention are particularly suitable for operation in so-called inverse or xcfx84V(min) mode (see, for example, J. C. Jones, M. J. Towler, J. R. Hughes, Displays 1993, 14, No. 2, 86-93; M. Koden, Ferroelectrics 1996, 179, 121-129).
Liquid-crystalline mixtures comprising compounds of the general formula (I) are particularly suitable for use in electro-optical switching and display devices (displays). These displays are usually constructed in such a way that a liquid-crystal layer is enclosed on both sides by layers which are usually, in this sequence starting from the LC layer, at least one alignment layer, electrodes and a limiting plate (for example of glass). In addition, they can contain spacers, adhesive frames, polarizers and, for color displays, thin color-filter layers. Other possible components are antireflection, passivation, compensation and barrier layers and electric non-linear elements, such as thin-film transistors (TFTs) and metal-insulator-metal (MIM) elements. The structure of liquid-crystal displays has already been described in detail in relevant monographs (see, for example, E. Kaneko, xe2x80x9cLiquid Crystal TV Displays: Principles and Applications of Liquid Crystal Displaysxe2x80x9d, KTK Scientific Publishers, 1987).
The invention therefore furthermore relates to a switching and/or display device, preferably a smectic or nematic switching and/or display device, in particular a ferroelectric switching and/or display device, containing a liquid-crystal mixture comprising one or more compounds of the formula (I).
In devices which contain a nematic liquid-crystal mixture, active matrix displays and in-plane switching displays (IPS-LCDs) are preferred.
In devices which contain a smectic liquid-crystal mixture, ECB (electrically controlled birefringence) displays, electroclinic displays and chiral tilted smectic (ferroelectric or antiferroelectric) displays are preferred.
Such displays can be used, for example, as computer displays or in smart cards.
A ferroelectric switching and/or display device according to the invention is preferably operated in normal or inverse mode.
Ferroelectric switching and/or display devices operated by multiplex addressing can be operated, inter alia, in two different modes, so-called normal mode or so-called inverse mode (xcfx84V(min) mode). The difference between the two is in the addressing scheme and in the different requirements made of the dielectric tensor of the FLC material, i.e. of the FLC mixture. An overview is given, for example, by J. C. Jones et al. in Displays 1993, 14, No. 2, 86-93, referred to below as xe2x80x9cJonesxe2x80x9d, and in M. Koden in Ferroelectrics 1996, 179, 121-129, and the literature cited therein.
The switching characteristics of an FLC device can generally be represented by a diagram in which the driving voltage (V) is plotted on the horizontal axis and the width of the addressing pulses (xcfx84, time) is plotted on the vertical axis (se Jones, FIGS. 4, 8, 10 and 11).
A switching curve is determined experimentally and divides the V,xcfx84 area into a switching region and a non-switching region. The pulse width usually shortens when the voltage is increased. This behavior characterizes so-called normal mode (see, for example, Jones, FIG. 4).
In suitable materials, however, the Vxcfx84 curve has a minimum (at voltage V(min)), as shown in Jones in FIGS. 8, 10 and 11. This minimum arises from superposition of dielectric and ferroelectric twist. FLC devices are operated in inverse mode if the sum of the row and column driving voltages in the operating temperature range is greater than the minimum on the Vxcfx84 curve, i.e. V(row)+V(column) greater than V(min).
In the present application, various documents are cited, for example in order to illustrate the technical background. All these documents are expressly incorporated herein by way of reference.
The invention is explained in greater detail by the following examples without a limitation being intended thereby.
In the present application, various documents are cited, for example in order to illustrate the technical background to the invention. All these documents are expressly incorporated herein by way of reference.

Fluorinated naphthalene derivatives and their use in liquid crystal mixtures

Abstract: where

Abstract: B is

Abstract: xe2x80x83having the meaning

Abstract: R1(xe2x80x94A1xe2x80x94M1)a(xe2x80x94A2xe2x80x94M2) and (xe2x80x94M3xe2x80x94A3)(M4xe2x80x94A4)R2 are mesogenic radicals, are suitable as components of liquid-crystal mixtures, in particular ferroelectric liquid-crystal mixtures.

Aventis Reseach and Technologies GmbH and Co. KG


An organic light emitting diode (OLED) display device with improved hole injection efficiency is presented, along with a method of making the display device. A thin film transistor (TFT) is formed on an insulating substrate. A pixel electrode is electrically connected to the TFT, and a hydrophilic wall is formed between the pixel electrode and an adjacent pixel electrode. A hole injecting layer and a first organic light emitting layer covering the pixel electrode and the hydrophilic wall and formed. Then, a second organic light emitting layer and a third organic light emitting layer are formed to partly cover the first organic light emitting layer.

1. Field of the Invention
The present invention relates to a display device and a method of making the display device.
2. Description of the Related Art
OLED (organic light emitting diode) is a type of flat panel display that has recently become popular. Some reasons for the increase in its popularity include advantages such as low-voltage driving, light weight, slim shape, wide angular field and quick response. OLED is classified into passive matrix and active matrix types depending on the driving method that is used. The passive matrix OLED is simple to manufacture but its power consumption rapidly increases with the display size and resolution. Therefore, the passive matrix OLED is mainly employed in small-display applications.
Unlike the passive matrix OLED, the active matrix OLED is complicated to manufacture. However, it is useful in big screen and high resolution applications.
In the active matrix OLED, a TFT is connected to each of a plurality of pixel areas. Each pixel area separately controls an organic light emitting layer that emits light. A pixel electrode is disposed in each pixel area and each pixel electrode is electrically separated from the adjacent pixel electrode so that each pixel electrode is driven separately. Further, a nonconductive wall is formed between adjacent pixel areas to prevent the pixel electrodes from short-circuiting and to separate the pixel areas. Between the walls, a hole injecting layer and the organic light emitting layer are sequentially formed on the pixel electrode.
The hole injecting layer, which is usually in an aqueous suspension state, is formed by ink-jetting on the pixel area and subjected to a drying process. However, since the wall is usually made of a polymer such as polyamide, which is hydrophobic, a de-wetting phenomenon occurs around the wall causing the hole injecting layer around the wall becomes thin. Accordingly, hole injecting efficiency decreases in the region around the wall, decreasing the brightness of the OLED device.

Display device with improved hole injection efficiency and method of making the same