A system for displaying an image includes a plurality of pixels each having a first organic light-emitting device (OLED), a second OLED and a third OLED. The pixel includes a first electrode layer, a first organic light-emitting layer, a second organic light-emitting layer, a second electrode layer and a color filter. The first organic light-emitting layer is disposed on the first electrode layer and within the first OLED and the second OLED. The second organic light-emitting layer is disposed on the first electrode layer and within the second OLED and the third OLED so that the first and second organic light-emitting layers overlap within the second OLED. The second electrode layer is disposed on the first organic light-emitting layer and the second organic light-emitting layer. The color filter is disposed within the second OLED.

1. Field of Invention
The invention relates to a system for displaying an image, and, in particular, to an image displaying system having organic light-emitting devices.
2. Related Art
An organic light-emitting device (OLED) has the advantages of self-emissive property, high luminance, high contrast, light weight, thin profile, low power-consumption and fast response speed. Due to these desirable qualities, it is becoming ever more widely used in various image displaying systems.
The OLED mainly includes a cathode, an electron transporting layer, an organic light-emitting layer, a hole transporting layer and an anode. The organic light-emitting layer is disposed between the electron transporting layer and the hole transporting layer. The cathode provides electrons to be injected into the electron transporting layer. The anode provides holes to be injected into the hole transporting layer. The electrons and the holes are respectively ejected from the electron transporting layer and the hole transporting layer and are recombined in the organic light-emitting layer so that the organic light-emitting layer emits light. Moreover, the OLED often serves as a pixel or a sub-pixel of the image displaying system.
Referring to FIG. 1a, a conventional image displaying system has a plurality of OLEDs, and three OLEDs may constitute a full-color pixel. A pixel 1 includes three OLEDs 11 to 13, and each of the OLED 11 to 13 has a transparent electrode layer 14, a red light organic light-emitting layer 15r, a blue light organic light-emitting layer 15b, a green light organic light-emitting layer 15g and a cathode reflective layer 16. The transparent electrode layer 14 has three transparent electrodes 141 to 143 respectively pertaining to the OLEDs 11 to 13. In addition, the red light organic light-emitting layer 15r, the blue light organic light-emitting layer 15b and the green light organic light-emitting layer 15g are sequentially disposed on the transparent electrodes 141 to 143, and the cathode reflective layer 16 is disposed on the organic light-emitting layers 15r, 15g and 15g. In addition, in order to increase the lighting efficiency, each of the OLEDs 11 to 13 may further include a hole transporting layer 17 disposed between the transparent electrode layer 14 and the red light organic light-emitting layer 15r, and an electron transporting layer 18 disposed between the green light organic light-emitting layer 15g and the cathode reflective layer 16. Herein, the red light organic light-emitting layer 15r may emit red light, the blue light organic light-emitting layer 15b may emit blue light, the green light organic light-emitting layer 15g may emit green light. The red light, the blue light and the green light are mixed to form white light.
In addition, the OLED 11 further has a red light filter 111 disposed opposite to the transparent electrode 141. The OLED 12 further has a blue light filter 121 disposed opposite to the transparent electrode 142. The OLED 13 further has a green light filter 131 disposed opposite to the transparent electrode 143. Thus, the white light is filtered to form the red light, the blue light and the green light such that the full-color displaying effect can be achieved.
When the OLEDs 11 to 13 are being manufactured, the red light organic light-emitting layer 15r, the blue light organic light-emitting layer 15b and the green light organic light-emitting layer 15g are sequentially deposited on the transparent electrode layer 14. When the red light organic light-emitting layer 15r, the blue light organic light-emitting layer 15b and the green light organic light-emitting layer 15g are disposed on the transparent electrodes 141 to 143, only one metal mask is used in the evaporating procedure. This is very advantageous to the manufacture of the OLEDs 11 to 13 because the yields of the OLEDs 11 to 13 may be influenced if the precision of the metal mask is not very highly controlled and the metal mask cannot be aligned very precisely. However, because each of the OLEDs 11 to 13 needs one filter for filtering, three manufacturing processes have to be performed to form three filters with different colors. Thus, the manufacturing processes are complicated, and the light intensity of each of the OLEDs 11 to 13 is absorbed by the corresponding filter so that the lighting efficiency of the OLED is decreased. In addition, if the light intensity has to be increased, the currents flowing through the OLEDs 11 to 13 have to be increased, thereby shortening the lifetime of each OLED.
Another pixel 1′, as shown in FIG. 1b, is different from the pixel 1 because the pixel 1′ only has a red light organic light-emitting layer 15r′ and a blue light organic light-emitting layer 15b′. The red light emitted from the red light organic light-emitting layer 15r′ and the blue light emitted from the blue light organic light-emitting layer 15b′ are mixed to form the white light, and the red light filter 111, the blue light filter 121 and the green light filter 131 are utilized to filter the white light into the red light, the blue light and the green light respectively so as to achieve the full-color displaying effect. Herein, the distributions of the lighting wavelengths of the red light organic light-emitting layer 15r′ and the blue light organic light-emitting layer 15b′ are respectively wider than those of the red light organic light-emitting layer 15r and the blue light organic light-emitting layer 15b of the pixel 1 so that the good light mixing effect can be achieved. As mentioned hereinabove, this pixel 1′ also has to be manufactured using three manufacturing processes to form the filters with various colors. So, the manufacturing processes are also complicated, the lighting intensity of each OLED is partially absorbed by the filter, the lighting efficiency of each OLED is likewise reduced, and the lifetime of each OLED is shortened.
As shown in FIG. 2, still another conventional pixel 2 includes three OLEDs 21 to 23 each having a transparent electrode layer 24. The transparent electrode layer 24 has three transparent electrodes 241 to 243 respectively pertaining to the OLEDs 21 to 23. In addition, the OLED 21 has a red light organic light-emitting layer 25r disposed on the transparent electrode 241. The OLED 22 has a blue light organic light-emitting layer 25b disposed on the transparent electrode 242. The OLED 23 has a green light organic light-emitting layer 25g disposed on the transparent electrode 243. In addition, the OLEDs 21 to 23 further have a cathode reflective layer 26 disposed on the red light organic light-emitting layer 25r, the blue light organic light-emitting layer 25b and the green light organic light-emitting layer 25g.
The OLEDs 21 to 23 may respectively output the red light, the blue light and the green light so as to achieve the full-color displaying effect. Because no filter is needed in the OLEDs 21 to 23, the lighting efficiency of each of the OLEDs 21 to 23 may be ensured. However, because the organic light-emitting layers 25r, 25b and 25g are respectively disposed on the transparent electrodes 241 to 243, three metal masks in precise alignment with one another have to be utilized in the evaporating procedure. This is very difficult in the manufacturing processes for high-resolution panel because the yields of the OLEDs 21 to 23 are restricted by the precision and alignment of the metal masks. In addition, the opening of each metal mask is smaller than that of the metal mask used to form the pixel 1 so that the precision has to be higher and the yields of the OLEDs 21 to 23 are thus reduced.
Thus, it is an important subject of the invention to provide an image displaying system having OLEDs, which are manufactured using the reduced number of metal masks, and the reduced number of color filters. Also, the opening of the metal mask is enlarged in order to enhance the yield and the efficiency of each OLED. Thus, the lighting efficiency of the OLED may be enhanced, and the lifetime thereof can be lengthened.


A method of preparation of gypsum wallboard, as well as a core composition suitable for use therein, are disclosed. The core composition includes a slurry of calcium sulfate hemihydrate (stucco), water, and calcium aluminum lignosulfonate and/or aluminum lignosulfonate.

1. Field of the Invention
The present invention relates generally to gypsum containing materials, and is also directed to improved methods for producing gypsum board and related materials.
2. Description of Related Technology
Today one of the most common manners of constructing walls and barriers includes the use of inorganic wallboard panels or sheets, such as gypsum wallboard, sometimes referred to as "wallboard," "drywall," or "plasterboard." Wallboard can be formulated for interior, exterior, and wet area (such as bathroom) applications. The use of wallboard, as opposed to conventional wet plaster methods, is often desirable because the installation of wallboard can be less costly and faster than installation of conventional plaster walls.
Walls and ceilings made with gypsum wallboard panels are conventionally constructed by securing, e.g., with nails or screws, the wallboard panels to structural members, for example vertically and horizontally oriented pieces of steel or wood such as "studs." Because wallboard is typically supplied in standard-sized sheets or panels, when forming a wall from the sheets or panels, there will generally be a number of joints between adjacent sheets. In most wallboard construction, these joints are filled and coated with wallboard tape and an adhesive material called joint compound so that the wall will have a monolithic finish similar to that obtained with conventional wet plaster methods. Various joint compounds are described in U.S. Pat. No. 5,653,797, assigned to the assignee of the present application, the disclosure of which is hereby incorporated herein by reference.
Generally, wallboard is conventionally produced by enclosing a core containing an aqueous slurry of calcium sulfate hemihydrate (e.g., calcined gypsum) between two large sheets of board cover paper. Gypsum wallboard is typically manufactured commercially by processes that are capable of operation under continuous high speed conditions, wherein the aqueous slurry of calcined gypsum and other ingredients are continuously deposited to form a core between two continuously-supplied moving sheets of cover paper. Various types of cover paper are known in the art.
The calcined gypsum forming the core between the two cover sheets is then allowed to set (react with water from the aqueous slurry). The continuously-produced board may then be cut into panels of a desired length (for example, eight feet). The formed board contains an excess of water because more water is required for working properties during gypsum slurry preparation than is necessary for hydration of the gypsum. The boards are then passed through a drying kiln in which excess water is removed and the gypsum is brought to a final dry state. After the core has set and is dried, the sandwich becomes a strong, rigid, fire-resistant building material called gypsum drywall.
Other methods for the production of gypsum wallboard are described, for example, in the Kirk-Othmer Encyclopedia of Chemical Technology, Vol. 21, pages 621-24 (Second Edition 1970) and Vol. 4, pages 618-19 (Fourth Edition 1992), the disclosures of which are hereby incorporated herein by reference.
A major ingredient of the gypsum wallboard core is calcium sulfate hemihydrate, commonly referred to as "stucco" or "Plaster of Paris." Stucco is commonly manufactured by drying, grinding, and calcining natural gypsum rock. The drying step of stucco manufacture includes passing crude gypsum rock through a rotary kiln to remove any free moisture accumulated in the rock from rain or snow, for example. The dried rock is then passed through a roller mill (a type of pulverizer), wherein the rock is ground to a desired fineness. The dried, ground gypsum can be referred to as "land plaster."
The calcination step is performed by heating the ground gypsum rock, and is described by the following chemical equation: EQU CaSO.sub.4.2H.sub.2 O+heat-->CaSO.sub.4.11/2H.sub.2 O+.1/2H.sub.2 O.
This chemical equation shows that calcium sulfate dihydrate plus heat yields calcium sulfate hemihydrate (stucco) plus water vapor. This process is conducted in a "calciner," of which there are several types known in the art. Various methods of producing calcium sulfate hemihydrate are known in the art.
Uncalcined calcium sulfate (the land plaster) is the "stable" form of gypsum. However, calcined gypsum, or stucco, has the valuable property of being chemically reactive with water, and will "set" rather quickly when the two are mixed together. This setting reaction is a reversal of the above-described chemical reaction performed during the calcination step. The reaction proceeds according to the following equation: EQU CaSO.sub.4.1/2H.sub.2 O+11/2H.sub.2 O-->CaSO.sub.4.2H.sub.2 O+heat.
In this reaction, the calcium sulfate hemihydrate is rehydrated to its dihydrate state over a fairly short period of time. The actual time required for this setting reaction is generally dependent upon the type of calciner employed and the type of gypsum rock that is used, and can be controlled within certain limits by the use of additives such as accelerators and retarders.
In the hydration reaction, hemihydrate gypsum is mixed with water until a suspension is formed that is fluid and workable. The hemihydrate gypsum dissolves until it forms a saturated solution. This saturated solution of hemihydrate is supersaturated with respect to dihydrate gypsum, and so the latter crystallizes out of the solution at suitable nucleation sites. Finally, as the dihydrate gypsum precipitates, the solution is no longer saturated with hemihydrate gypsum, so the hemihydrate gypsum continues to dissolve. Thus the process continues to consume the hemihydrate gypsum. The reaction can be followed by measuring the heat evolved. Initially there is very little reaction and no rise in temperature. This time is referred to as the induction period. As the amount of dihydrate gypsum increases, the mass thickness increases and the material hardens (sets).
In order to facilitate the above reaction and/or provide beneficial properties to the final product, various additives may also be included in the core slurry. For example, starch, set accelerators and/or set retarders, preservatives, and fiberglass may be included.
As described above, the setting reaction for gypsum involves the reaction of calcium sulfate hemihydrate with water to form calcium sulfate dihydrate. The theoretical (stoichiometric) water content of the slurry required for the reaction of calcium sulfate hemihydrate is about 18.7 weight percent. However, a large amount of water is generally required to provide sufficient fluidity of the calcined gypsum slurry in order to obtain proper flow of the gypsum slurry in the manufacturing process. The amount of water required to provide proper fluidity depends upon various factors, such as the type of stucco, particle size distribution, the various phases of gypsum in the stucco, source, and the levels of above-described additives conventionally used in minor amounts.
Alpha-type stucco generally requires water usage of about 34 to about 45 cubic centimeters per 100 grams of calcined gypsum in order to form a readily pourable and flowable gypsum slurry. Beta-type stucco, on the other hand, typically has a water requirement of about 65 to about 75 cubic centimeters per 100 grams of calcined gypsum.
"Water reducing" additives may be included in order to improve the fluidity of the above-described gypsum slurry, while allowing use of reduced levels of water. Reduction in water usage brings reduced costs in the form of reduced water and energy demands, as less water will have to be removed during the drying step(s). Reduction of water usage also provides environmental benefits.
Various commercially-available fluidity-enhancing and/or water-reducing agents are known in the art for various applications. Typically the dispersing agent used in gypsum board manufacturing processes are calcium lignosulfonate, ammonium lignosulfonate, sodium lignosulfonate, and naphthalene sulfonate. Calcium lignosulfonate, sodium lignosulfonate, and ammonium lignosulfonate are believed to provide the ability to use reduced water levels, but they have the severe disadvantage of inhibiting the set of gypsum in the hydration reaction discussed above. Sodium lignosulfonate provides a weak paper-to-core interface in wallboard products. Ammonium lignosulfonate also has an objectionable odor due to the release of ammonia gas during the manufacturing process. The use of naphthalene sulfonate is limited, for example, due to its high cost. The use of condensation products of naphthalene sulfonic acid and formaldehyde is also known. See also U.S. Pat. No. 4,184,887, the disclosure of which is hereby incorporated herein by reference.
The use of the following additives in one or more applications is also known: anionic dispersing agents (such as alkylaryl sulfonates and lignin sulfonates) and higher molecular weight anionic condensation products (such as melamine formaldehyde modified with sulfite, as well as naphthalene sulfonate).
Water reducing agents are described in "The Gypsum Industry and Flue Gas Desulfurization (FGD) Gypsum Utilization: A Utility Guide," New York State Electric & Gas Corp. and ORTECH, pp. 3-38 (1994), the disclosure of which is hereby incorporated herein by reference.
The use of water reducing agents in another art, i.e., concrete, is described, for example, in "Water Reducing Chemical Admixtures," V. Dodson, Concrete Admixtures, Chapter 3, pp. 39-71 (1990), the disclosure of which is hereby incorporated herein by reference.
It would therefore be advantageous to provide a gypsum wallboard manufacturing process using a fluidity-enhancing additive that does not produce the set retarding effect suffered by some known manufacturing processes. Such wallboard also should be able to be manufactured through the use of conventional high-speed manufacturing apparatus, and not suffer from high cost or other negative side-effects such as detriment to long-term product performance.

Gypsum wallboard, and method of making same


A method and preparation for the stimulation of tear secretion in a subject in need of such treatment is disclosed. The method comprises administering to the ocular surfaces of the subject a purinergic receptor agonist such as uridine 5'-triphosphate UTP!, dinucleotides, cytidine 5'-triphosphate CTP!, adenosine 5'-triphosphate ATP!, or their therapeutically useful analogs and derivatives, in an amount effective to stimulate tear fluid secretion. Pharmaceutical formulations and methods of making the same are also disclosed. Methods of administering the same would include: topical administration via a liquid, gel, cream, or as part of a contact lens or selective release membrane; or systemic administration via nasal drops or spray, inhalation by nebulizer or other device, oral form (liquid or pill), injectable, intra-operative instillation or suppository form.

There are many situations where it is therapeutically desirable to increase the amount of tear fluid produced by the eye. Dry eye disease is the general term for indications produced by abnormalities of the precorneal tear film characterized by a decrease in tear production or an increase in tear film evaporation, together with the ocular surface disease that results. Approximately 38 million Americans are affected with some type of dry eye disorder. Among the indications that are referred to by the general term "dry eye disease" are: keratoconjunctivitis sicca (KCS), age-related dry eye, Stevens-Johnson syndrome, Sjogren's syndrome, ocular cicatrical pemphigoid, blepharitis, corneal injury, infection, Riley-Day syndrome, congenital alacrima, nutritional disorders or deficiencies (including vitamins), pharmacologic side effects, eye stress and glandular and tissue destruction, environmental exposure to smog, smoke, excessively dry air, airborne particulates, autoimmune and other immunodeficient disorders, and comatose patients rendered unable to blink. The present invention may also be useful as a wash or irrigation solution in conscious individuals, during surgery or to maintain comatose patients or those who cannot blink due to neuromuscular blockade or loss of the eyelids.
A healthy precorneal tear film has several important functions: 1) to protect the cornea from dessication; 2) to aid in the immune response to infections; 3) to enhance oxygen permeation into the cornea; 4) to allow gliding movement of the eyeball and eyelids; and 5) to help maintain the ocular pressure through osmosis. There are two structures responsible for maintaining the properties of the tear film--the lacrimal glands and the conjunctiva (the mucous membrane which surrounds part of the eyeball and inner eyelids). These structures maintain the tear film via regulation of water and electrolyte transport and via mucin release by goblet cells.
The progression of dry eye disease is characterized by four main "milestones". The first milestone is a decrease in tear production. In rabbit models, this decrease in tear production has been shown to correlate with an increase in tear osmolarity. The second milestone is a loss of mucous-containing conjunctival goblet cells. This decrease in goblet cell density becomes evident several weeks after the onset of decreased tear production. The third milestone in the progression of dry eye disease occurs about 1 year later when desquamation of the corneal epithelium is observed. The fourth and last milestone of the disease is a destabilization of the cornea-tear interface (J. Gilbard, CLAO Journal 22(2), 141-45 (1996)).
Currently, the pharmaceutical treatment of dry eye disease is mostly limited to administration of artificial tears (saline solution) to temporarily rehydrate the eyes. However, relief is short-lived and frequent dosing is necessary. In addition, artificial tears often have contra-indications and incompatibility with soft contact lenses (M. Lemp, Cornea 9(1), S48-S50 (1990)). The use of phosphodiesterase inhibitors, such as 3-isobutyl--1--methylxanthine (IBMX) to stimulate tear secretion is disclosed in U.S. Pat. No. 4,753,945 (applicant intends this and all other patent references to be incorporated herein). The effectiveness of these phosphodiesterase inhibitors is currently being investigated (J. Gilbard, et al., Arch. Ophthal. 112, 1614-16 (1994) and 109, 672-76 (1991); idem, Inv. Ophthal. Vis. Sci. 31, 1381-88 (1990)). Stimulation of tear secretion by topical application of melanocyte stimulating hormones is described in U.S. Pat. No. 4,868,154.
Thus, as a result of the ineffectiveness and inconvenience of current therapies, medical researchers have sought to develop alternatives for the treatment of dry eye disorders. It has been shown that uridine 5'-triphosphate (UTP) and adenine 5'-triphosphate (ATP) are potent agonists of P2Y.sub.2 purinergic receptors found on the surface of human airway epithelium. Activation of these P2Y.sub.2 purinergic receptors induces chloride and water secretion, helping hydrate the airway surface secretions. Use of UTP and ATP for the purpose of treating pulmonary disorders characterized by the retention of lung mucus secretions is described in U.S. Pat. No. 5,292,498. Because of the demonstrated ability of UTP to increase hydration of airway epithelial secretions, applicants were motivated to investigate whether UTP and other P2Y.sub.2 and P2Y.sub.4 purinergic receptor agonists could also stimulate hydration of ocular epithelia. It had previously been shown that P2 type purinergic receptors in rat and mouse lacrimal acinar cells responded to extracellular ATP by increasing intracellular calcium (I. Sasaki, et al., Febs Lett. 264, 130-34 (1990); idem, J Physiol. 447, 103-18 (1992); P. Vincent, J Physiol. 449, 313-31 (1992); J. Gromada, et al., Eur. J Physiol. 429, 578 (1995)). Additionally, the same mucin types observed in the human trachea have been observed in the eye (T. Inatomi, et al., Inv. Ophthal. Vis. Sci. 37, 1684 (1996)).
Applicant has discovered that tear secretion can be stimulated from lacrimal accessory tissues via P2Y.sub.2 and/or P2Y.sub.4 purinergic receptor-mediated mechanisms similar to those which hydrate airway epithelia. UTP and other purinergic receptor agonists, administered topically or systemically, provide a novel method of treating dry eye disorders.

Method of treating dry eye disease with uridine triphosphates and related compounds


An E Bliss compartmented container comprising an erected E divider blank about which a Bliss body blank has been erected with its endwalls adhesively laminated to endwall panels of the E divider. The E blank comprises a rectangular piece of corrugated fiberboard material having a pair of divider panels, a pair of sidewall panels, a pair of endwall panels and, if desired, a pair of corner post flanges, all symmetrically arrayed about a longitudinal center line. The divider panels comprise the end-most pair of all of the panels of the blank which is completely severed through from end to end along the longitudinal center line, except for a spaced apart pair of intact crush score areas interconnecting the pair of divider panels as a hinge. The body blank comprises a substantially rectangular piece of material having a central bottom panel with integral opposite endwall panels and a pair of sidewall flaps.

The present invention relates to the manufacture of paperboard containers and, more particularly, compartmented shipping and display containers. It is known in the prior art to make a display or shipping container by first making a regular slotted container (RSC) or a half slotted container (HSC), loading the container with the product (e.g., bottles), and thereafter inserting into the thus preformed tray container a generally E shaped divider strip. The blank of which the E divider is formed is of a width the same as the height of the RSC or HSC container and has an overall length equal to the sum of the container walls to be doubled and the two panels comprising the divider partition. The E blank thus comprises a long spindly piece which creates shipping problems for the corrugator and handling problems for the box maker. The E blank is typically first folded into the E configuration and then manually or machine inserted into the preformed RSC or HSC container.
An E blank and a companion body blank are assembled to make a compartmented container for either a display container or a shipping container. The E blank comprises a rectangular piece of corrugated fiberboard material having, symmetrically arrayed about a longitudinal center line, a pair of divider panels, a pair of sidewall panels, a pair of endwall panels and, if desired, a pair of corner post flanges. The divider panels comprise an end-most pair of all the panels of the blank. The E blank is completely severed through from end to end along the longitudinal center line, except for a spaced apart pair of intact crush score areas inter-connecting the pair of divider panels as a hinge.
The body blank comprises a substantially rectangular piece of corrugated material having a central bottom panel with integral opposite end wall panels. In the case of a display container, the bottom wall panel has a pair of opposite side wall flaps, one of which comprises a marginal window flap. In this case, the end wall panels are each flanked by marginal corner flaps on opposite sides, one of which is is formed with a joggled portion to cover a notch of a corner post flange of the companion end wall of the E divider, the flange being thus configured to provide a recess for one end of the window flap. In the case of a shipping container, the opposite side marginal flaps of the bottom panel are similar, as are the marginal corner post flaps of the end wall panels.
In the assembly of a display container of the invention, the flat E blank is advanced in a horizontal plane to a first station wherein the divider panels are restrained horizontally while the side wall panels, end wall panels and corner post flaps or flanges are turned downward 90 degrees. The blank is next advanced to a position over a split mandrel into which the divider panels are next folded together. Folding of the divider panels effects rotation of the side wall panels, end wall panels and marginal flaps into a horizontal position while those flaps are being restrained within a common vertical plane. Thereafter, the end wall panels and corner post flaps are progressively folded about the mandrel.
In the case of a shipper box, the pair of divider panels carry another pair of side wall panels while the manner of the formation of the box is substantially similar to that of the display container.
During the folding assembly process, adhesive is applied to produce a laminated pair of divider panels as a result of their folding. Adhesive is also applied to all areas of the body blank except the floor panels such that the resulting structure comprises adhesively laminated together vertical members on all four sides.


An electronic device having a memory, a display, control apparatus and a data processor. When the data processor executes a program stored in the memory of the electronic device, the electronic device receives an image containing a person, the image further containing a face component, the face component containing the face of the person; displays the image on the display; locates the face component within the image; emphasizes the face component; receives image annotation information concerning the face component; and saves the image annotation information to the memory of the electronic device. The image annotation information may take the form of contact information for use in a contact database. A method uses the face component to locate other images in the database that also contain the person, and adds the annotation information to those images.

Wireless telephones that incorporate cameras are extremely popular. The ability to capture images with a camera, and to save them to a memory of a wireless telephone incorporating the camera, presents not only new opportunities for using the images to perform certain functions within the context of the wireless telephone, but also new challenges, as users are confronted with the necessity to organize the images.
Perhaps the most common use of cameras associated with wireless telephones is to take pictures of family members; friends; business colleagues; business acquaintances; etc., especially since wireless telephones are networking devices and are used to perform networking functions. Accordingly, many photographs likely to be found in the memories of wireless telephones will contain images of people. As memories of wireless telephones increase in capacity, ever increasing numbers of images will be stored in wireless telephones. As a result, those skilled in the art seek methods and apparatus that facilitate organization of images. In particular, those skilled in the art especially desire methods and apparatus that draw upon or enhance existing functionality to perform image organization operations.
In addition, those skilled in the art also recognize that photographs in conventional wireless telephones serve merely a keepsake or memento function. For example, a person viewing photographs stored in a wireless telephone cannot use the photographs to initiate a communication operation. Those skilled in the art seek methods and apparatus that use photographs in some way to improve the functionality of telephones, and perhaps, to provide a more natural interface for managing communication operations that operates as a supplement to existing text-based contact databases. Such functionality would be particularly helpful to those who meet many people in their business activities. Having access to "functional" photographs could assist such users in following up contacts after a busy trade show, for example, when names in a contact list may not be enough to stir a memory.
As a result, those skilled in the art are particularly concerned with finding new methods and apparatus that use the human component of images to assist in performing communication operations and image organization functions in, for example, a wireless telephone. For example, those skilled in the art are concerned with finding some way to use the human component of images to improve the functionality of contact databases often incorporated in wireless telephones, and possibly to supplement contact databases. In addition, those skilled in the art are more generally concerned with using the human component to improve image organization functionality in wireless telephones containing cameras and other image capture devices.

Apparatus, method and computer program product for using images in contact lists maintained in electronic devices


A method and system for controlling computer operation time is provided for counting how long the time for using the computer lasts. The steps of the time counting method are as following. First step is counting an operation time period for using the computer at the computer powered on; second step is determining the operation time period equal to a predetermined operating-time limit; third step is controlling the computer into an interrupted operating state when the operation time period is equal to the predetermined operating-time limit, wherein an interrupted time period for the computer stayed in the interrupted operating state is counted; fourth step is determining the interrupted time period equal to a predetermined suspension time; and fifth step is controlling the computer back to a normal operating state when the interrupted time period is equal to the predetermined suspension time, wherein the operation time period is re-counted.

1. Field of the Invention
The present invention relates to a management of a computer operation and in particular to a method and system for controlling an operation time of a computer.
2. Description of Prior Art
The computer technology is developed increasingly so that computers are extremely common in office, classroom, and house. However, if a user lasts a long time for using the computer, for example, looking at monitor for a long time, operating mouse and keyboard repetitively or seating on the chair for a long time, the tendon and the sinew, the bone or the nerve of the eyes, the cervical vertebra, the lumbar vertebra and the wrist are easily got hurt. RSI (repetitive stress injuries) and CTS (carpal tunnel syndrome) are caused due to the improper computer use.
For preventing from the above injuries, ergonomics are now applied to the design of many elements of everyday life. However, the ergonomic environment for using the computer results in a longer time of computer use, the user works at computer keyboards without taking regular rest breaks. Doctors suggest that after working at the computer for one to two hours, the user have to rest for five to ten minutes so as to relieve the pressure on the human body and eyes.
From now on, the computer system is applied for a function of screensaver program so that the monitor is controlled to display a video after using for a certain time period. The lifetime of the monitor is increased because of reducing the use time of the monitor. Moreover, an issued patent, U.S. Pat. No. 6,579,209 disclosed a method for controlling a monitor to display a video of relieving body or eyes in a predetermined time. The user can follow the video to move body parts so as to reduce the pressure on the body. However the user can interrupt the display of the video on his demand, the effect of the mechanism is limited.
Therefore, in view of solving the computer-relative injures of children and people working at the computer, the inventor proposes the present invention to interrupt the operation of the computer to overcome the above problems based on his expert experience and deliberate research. The present invention can be employed widely on the computer in home, school and the public place.

Method and system for controlling an operation time of a computer


A no skill, automatic play blackjack game and apparatus enables fully automated play of a blackjack machine with no skill required and the player enabled to wager one or more of three player hands against the dealer hand and/or on a dealer hand against one or more of three player hands. All play is automatic with ability to exercise choices in any hit, stand, double down or split decisions.

1. Field of the Invention
The present technology relates to the field of gaming, particular playing card games, particularly blackjack gaming technology, and most limitedly with respect to automated play of blackjack gaming technology with multiple player hands.
2. Background of the Art
Blackjack, also known as Twenty-One, is a card game that has been played for many decades by recreational players and gamblers. Blackjack is a mainstay at casinos all over the United States and the world.
Generally, at casinos, blackjack is played according to a set of standardized rules. These standardized rules include rules regarding the play of the cards and rules regarding how the players may place wagers.
In recent years, video blackjack has become popular. Video blackjack (also referred to as electronic blackjack) is played on stand-alone gaming devices or on client devices, such as computers or the like, which communicate with servers over a network, such as the Internet.
Typically, video blackjack is played by individuals against the house (also referred to as the "dealer). The dealing of the cards from virtual decks and shoes is controlled by one or more computers. Certain known video blackjack games permit a player to play several hands simultaneously against a dealer hand. Such games permit the player to obtain a greater number of game outcomes per duration of time played, and at the same time, typically enables the video blackjack provider to increase profits due to the increased number of outcomes.
However, these prior art games do not take full advantage of the increased game speed and number of outcomes possible using electronic means, such as the Internet or gaming machines. Accordingly, there is a need for systems and methods for playing an improved electronic multi-hand blackjack game. The following patents describe technology intended to provide better multi-play blackjack games.
U.S. Pat. No. 8,408,983 (Dunaevsky) discloses a method and gaming device for playing an electronic multi-hand blackjack game. The game includes: a) dealing a player hand of two face-up cards; b) dealing two or more dealer hands such that each dealer hand is dealt from a corresponding shoe made up on at least one deck of cards, where each dealer hand includes one identical face-up card and one face-down card; c) completing the player hand according to input received from the player; d) completing each of the dealer hands according to conventional rules of blackjack, such that the cards in each dealer hand are drawn from the corresponding shoe and no two dealer hands are drawn from the same shoe; and e) determining a number of game results by comparing the player hand against each of the dealer hands using conventional rules of blackjack.
U.S. Pat. Nos. 6,969,316 and 6,726,427 (Jarvis) disclose a method of playing a Blackjack or Twenty-One game that will enable a player to play single or multiple hands and/or wagers against single or multiple dealer hands in a rapid and substantially automatic fashion. In addition, the player can pre-select the point value at which to "stand," "split," "double," "surrender," and/or "take insurance," when playing single or multiple hands. The pre-selected strategy can then be duplicated across all player hands being played. The player can also select to "auto-play" one or more hands according to a preset strategy at which to "stand," "split," "double," "surrender," and/or "take insurance," when playing single or multiple hands. The preselected strategy can then be duplicated across all player hands being played. The player can also select to "auto-play" one or more hands according to a preset strategy.
U.S. Pat. No. 6,311,978 (Moody) discloses a game of Twenty-One in which the player has the opportunity to play his first two cards multiple times. The player makes two or more wagers at the beginning of the hand. The player is dealt two cards which may be dealt two cards to each player, or one card to each player and one community card common to all players or two community cards common to each player. The player uses the first two cards as his first hand with his first wager and plays these two cards as he would in the conventional manner of play of Twenty-One. The player may Double Down, split pairs, take Insurance and/or Surrender. After the player has completed the play of his first hand, he uses his original two cards again as the first two cards of his second hand with his second wager. Again, the player plays his second hand as he would in the conventional manner of play of Twenty-One. If the player has made three or more wagers, the player repeats the play of each hand again using his first two cards with each additional wager. Once the player has completed the play of his hands, the dealer plays out his hand as he would in the conventional manner of play of Twenty-One. Each of the player's hands are compared to the dealer's hand and winning wagers are paid and losing wagers are collected.
U.S. Pat. No. 5,823,873 (Moody) discloses a method that involves a card game in which at least two rows of cards, and preferably three rows, are dealt to a player. The player makes a wager for each row of cards. One row of five cards are dealt all face up. The player selects none, one or more of the face up cards from the first row as cards to be held. The cards that are held are duplicated from the first row into all of the other rows. Replacement cards for the non-selected cards are dealt into the first row. Additional cards are also dealt to all of the other rows so that each row is a five card hand. The poker hand ranking of each five card hand by row is determined. The player is then paid for any winning poker hands based on a pay table and the amount of the player's wager.


A system and method improves linearly-polarized microstrip patch antenna performance and fabrication through the incorporation of a pin fin ground plane and an integral antenna feed assembly. In one embodiment, a patch antenna system includes an antenna area with a patch antenna that provides radio communications. A heat dissipation member is coupled to the antenna area and includes a plurality of pins that provide for both the dissipation of heat from the antenna area and a ground plane for the antenna area. An antenna feed line is further coupled with the antenna patch for providing an electrical connection from the antenna patch to other electronic circuitries, such as a wireless device that may be mechanically coupled to the heat dissipation member. Heat generated during the operation of the wireless device is directed to ambient air by way of the heat dissipation member.

The present invention relates generally to patch antennas, and more particularly to the utilization of a pin fin ground plane structure for a linearly-polarized patch antenna.
Patch antennas are planar antennas used in wireless links and other microwave applications. A conventional linearly-polarized, single-band patch antenna consists of a dielectric substrate with a ground plane on the back-side of the dielectric substrate. On the front-side of the dielectric substrate is a square or rectangular conductive area also known as a "patch", which gives patch antenna its name. Typically a coaxial cable acts as a feed line to and from the "patch" for transmitting or receiving signals. In addition, the length of the patch in the direction of the feed is typically slightly less than half a wavelength of the operating frequency.
The ease of patch antenna fabrication on a flat substrate is a main selling point of the patch antenna. Though patch antennas have low gain as compared to large dish/parabolic type antennas, they can be arranged in an array to achieve higher gains. A commercial patch antenna, when opened up, typically involves an array of different shaped patches. For linearly-polarized radiation, the simplest patch element is a rectangle.
However, there are certain deficiencies with respect to a conventional patch antenna design. The resonant length of a conventional patch antenna is directly proportional to the intrinsic speed of light in the dielectric substrate over a flat ground plane, which is typically a published value for the substrate material. The radiating structure is a half wave resonating structure. An electric field exists between the patch and the ground plane. Since the field is not fully enclosed near its edges, fringing fields, which in turn is a source of radiation, are generated. Other factors also influence the resonant frequency of the patch antenna. These factors include: ground plane size, dielectric substrate thickness, metal (copper) thickness, and patch width (impedance). The width of the patch is chosen to provide a suitable radiation resistance and operational bandwidth.
Desirable in the art of linearly-polarized microstrip patch antenna, are improved patch antenna designs that provide for smaller size, lower weight, and decreased fabrication and assembly costs while maintaining conventional patch antenna performance.

Pin fin ground plane for a patch antenna


A system and method for mounting fishing reels on a mounting surface. The system employs a base member having retaining walls and detent members. The base member is mounted on the mounting surface. Tangs on the reel are held by the detent members against the retaining walls to hold the reel in place. A stop member is formed on an inner surface of one of the retaining walls to reduce the likelihood that the reel will become inadvertently dislodged. The base member is designed to be injection molded as a single part.

Fishing reels are often designed for a specific style of fishing or type of fishing line or rod. Fisherman will thus often purchase a number of fishing reels so that the appropriate reel may be used in a given situation.
Additionally, fishing reels are normally detachable from rods, and the rods are often stored in tubes. So even if one reel and one rod are owned, the fisherman may want to remove the reel from the rod when the assembly is not in use so that the rod and reel may be stored separately.
In these and other cases, the fisherman is faced with the problem of storing fishing reels that are not in use.
Fishing reels are fairly delicate devices and often quite expensive. Care must be taken when storing fishing reels to ensure that they are not damaged. And in some cases the fisherman would like to avoid even scratching the finish on a fishing reel for aesthetic purposes or to avoid possible corrosion.
Thus, while it is possible simply to store fishing reels in a tackle box or the like, many fisherman would like to avoid this approach and thereby avoid damaging the reel.


A CPU 411 divides image data GD into a plurality of areas (pixel data groups), analyzes the data in image data area units, and determines the color value and dispersion value of the image data areas. When the determined color value is within a flesh toned color area and the dispersion value is at or below a reference dispersion value, the CPU 411 determines the target image data area to be a flesh area. The CPU 411 carries out a smoothing process on the image data area determined to be a flesh area.

1. Field of the Invention
The present invention relates to a technique that specifies flesh areas contained in an image, and a technique that implements a smoothing process on image data corresponding to flesh areas.
2. Description of the Related Art
As the resolution of digital still cameras grows ever higher, so too do pigmentation spots, age spots, and blemishes become more conspicuous in the flesh areas of images that are produced. After a photograph has been taken, a process for adjusting picture quality can be readily implemented on the digital image data produced by digital still cameras. Practical use is now being made of techniques for reducing or eliminating parts where faithfully reproducing pigmentation spots, age spots, and blemishes in the flesh areas of an image would be undesirable.
Specifically, flesh areas in the image can be specified, and a smoothing process can be implemented on image data corresponding to the flesh areas to reduce or eliminate such spots and the like in the flesh areas.
However, a problem in conventional techniques or specifying flesh areas is the low accuracy in identifying flesh areas because such flesh areas are determined based on the presence of parts forming the face, such as the eyes and mouth, or the shape of the areas. Low accuracy in identifying flesh areas results in the smoothing process being carried out on areas that do not represent flesh, and thus in lower image reproduction accuracy, that is, lower picture quality. An example of a resulting problem is that a flesh toned sweater could be identified as a flesh area, and the coarse texture of the sweater could be eliminated.


A portable, foldable surfacing module is disclosed for use by road vehicles as a road surface over previously impassable terrain. The surfacing module employs hinged sections that are rotatable through 360 degrees relative to each other and are foldable upon each other in accordian fashion for convenient storage, transport, deployment and retrieval.

1. Field of the Invention
The invention relates to portable, folding road surfaces primarily employed in military applications.
2. Discussion of the Prior Art
U.S. Pat. No. 4,488,833 to Perry et al. shows the use of hinged multi-hollow sections which may be laid from an accordian position. The individual planks, however, are not pivotable through 360 degrees relative to each other since each plank is folded into its accordian storage position in a single, preset direction of rotation.
Similarly, U.S. Pat. Nos. 4,277,201 to Abell and 3,284,819 to Nissen also show portable roadbeds which lack the 360 degree rotation characteristic.
Finally, U.S. Pat. No. 4,460,291 to Lamendour shows a flexible, portable roadbed wherein a significant degree of rotational flexibility exists between the respective components. However, 360 degree rotation is obviously not possible due to the configuration of the individual members. Further, the top and bottom surfaces of the members are not identical and therefore the roadbed has a specific top and bottom.


A method of manufacturing hard pelleted activated carbon is disclosed in which pellets are first formed by agglomeration in a pin mixer followed by pelleting the plasticized acid char (without the use of additional binders), and then activating the carbon pellets to yield a product with high density and activity.

1. Field of the Invention
The present invention relates to activated carbon and methods for preparing same. Particularly, this invention relates to the preparation of gasoline adsorptive activated carbons and their use in emission control canisters for gasoline powered vehicles. More particularly, this invention relates to activated carbon derived from lignocellulosic material prepared by chemical activation, agglomeration, and shaping of the agglomerated carbon.
2. Description of the Prior Art L. Activated carbon is a microcrystalline, nongraphitic form of carbon which has been processed to increase internal porosity. Activated carbons are characterized by a large specific surface area typically in the range of 500-2500 m.sup.2 /g, which permits its industrial use in the purification of liquids and gases by the adsorption of gases and vapors from gases and of dissolved or dispersed substances from liquids. Commercial grades of activated carbon are designated as either gas-phase or liquid-phase adsorbents. Liquid-phase carbons generally may be powdered, granular, or shaped; gas-phase, vapor-adsorbent carbons are hard granules or hard, relatively dust-free shaped pellets. The present invention relates to shaped (pelleted), gas-phase vapor-adsorbent active carbons.
Generally, the larger the surface area of the activated carbon, the greater its adsorption capacity. The available surface area of activated carbon is dependent on its pore volume. Since the surface area per unit volume decreases as individual pore size increases, large surface area generally is maximized by maximizing the number of pores of very small dimensions and/or minimizing the number of pores of very large dimensions. Pore sizes are defined herein as micropores (pore width <1.8 nm), mesopores (pore width =1.8-50 nm), and macropores (pore width<50 nm). Mesopores may be further divided between small mesopores (pore width =1.8-5 nm) and large mesopores (pore width=<5-50 nm).
The liquid adsorptive capacity of the activated carbon relies primarily on large mesopores and macropores. As noted above, high macropore content normally is detrimental to the activated carbon's density characteristics, particularly if the activated carbon is derived from a lignocellulosic material. Microporosity, which may contribute to density, is detrimental to the liquid adsorbent effectiveness of the activated carbon, on a carbon volume basis.
The vapor adsorptive capacity of the activated carbon, on the other hand, relies primarily on micropores and small mesopores; whereas, the macropores reduce the density and can be detrimental to the vapor adsorbent effectiveness of the activated carbon, on a carbon volume basis. The adsorption capacity and rate of adsorption depend to a large extent upon the internal surface area and pore size distribution. Conventional chemically activated llanocellulose-based carbons generally exhibit macroporosity (macropore volume) of greater than 20% of the carbon particle total volume. Gas-phase activated carbon macroporosity of less than 20% of the carbon particle volume would be desirable. Likewise, a high percentage of mesoporosity (i.e., above 50% of total particle volume), particularly small mesoporosity, is desirable.
Due to environmental concerns and regulatory mandates, one of the largest single applications for gas-phase carbon is in gasoline vapor emission control canisters on automobiles. Evaporative emissions vented from both fuel tank and carburetor are captured by activated carbon.
Fuel vapors, vented when the fuel tank or carburetor is heated, are captured in canisters generally containing from 0.5 to 2 liters of activated carbon. Regeneration of the carbon is accomplished by using intake manifold vacuum to draw air through the canister. The air carries desorbed vapor into the engine where it is burned during normal operation. An evaporative emission control carbon should have suitable hardness, a high vapor working capacity, and a high saturation capacity. The working capacity of a carbon for gasoline vapor is determined by the adsorption-desorption capacity differential, by the volume of purge air which flows through the carbon canister, and by the extent to which irreversibly adsorbed, high molecular weight gasoline components accumulate on the carbon.
The ability to prepare an activated carbon of a higher density, higher hardness, and smaller median pore size from a material of a lower density, lower hardness, and large median pore size is taught in U.S. Pat. No. 4,677,086. An active granular wood-based carbon is ground to a fine powder, mixed with water and a bentonite clay binder, extruded to form cylindrical pellets, oven dried, and heat treated at 1,000.degree. F. The uniform pellet form provides consistent particle size and a regular pellet shape which minimizes pressure drop in gas phase applications.
Also, U.S. Pat. No. 5,039,651 teaches densification of activated carbon product from cellulose materials including coconut shells, wood chips, and sawdust by pressing after initially heating to a relatively low temperature, followed by extrusion and calcination.
U.S. Pat. No. 5,206,207 discloses activated carbons of high activity and relatively high density suitable for solvent and vapor capture and recovery prepared by chemically activating carbonaceous material fragments (i.e., "discrete particles"), heat plasticizing the particles to begin transition to thermoset, densifying the particles by mechanical shaping (in a spheronizer), further heating the shaped particles to thermoset, and still further heating the thermoset shaped particles to 425.degree. -650.degree. C. Unfortunately, the spheronizing equipment limitations related to such process restrict capacity to below commercial production levels.
A more commercially feasible process of making activated carbons of high activity and relatively high density suitable for solvent and vapor capture and recovery is disclosed in co-pending (parent) U.S. patent application Ser. No. 07/929,166 which provides a chemical activation and agglomeration process for producing high activity gas-phase activated carbons without sacrificing density. While this process provides particles of fairly uniform size and shape, improvement in consistency of these characteristics is the primary object of the invention.

Method of preparation of gasoline vapor adsorptive activated carbon


A trigger actuated aerosol spray cleaning device has a cleaning head that swivel or be locked in different preset discrete angular positions relative to the device. The cleaning head pivotally mounts onto a swivel part of a coupler at and end of the device. In one position, a sliding swivel lock permits rotation of the swivel and in a locking position it prevents relative rotation by engaging one of several slots in the swivel. The slots are located so that the cleaning head can be centered (perpendicular) relative to the device or held at an oblique angle as may be desired for cleaning corners or other tight spaces.

A variety of cleaning devices have been developed which permit a cleaning head to be adjustably attached to a handle so that the head can pivot and/or swivel at the end of the handle during use. It is desirable for the pivot or swivel action to be temporarily or optionally suspending if not wanted, for example when vigorously scrubbing a soiled area. It is also desirable at times for the cleaning head to be fixed in an angular position relative to the handle (be it perpendicular or at an oblique angle), for example as when cleaning a tight space or corner or perhaps when cleaning a window or other nearby upright surface. It is also desirable that the consumer be able to quickly select a desired position and easily lock the head in the selected position. Releasing the head so that it is free to swivel should also be simple and intuitive. Additionally, it is desirable that the assembly provide a secure connection between the head and the handle in a simple motion with minimal requirement for the consumer to bend down to achieve the connection. Furthermore, it is desirable for the head to be removably attached to the handle to facilitate quick changing of the head when desired.
U.S. Pat. No. 2,802,230 discloses an articulating mop in which the mop head can swivel in a circular motion about the handle and in which the handle can pivot up and down relative to the mop head. The pivoting connection of this device allows for only about 90 degrees of pivoting and requires the consumer to twist the handle to rotate the head. Also, the disclosed mechanism does not provide for locking the head in either a perpendicular or oblique angular position. Furthermore, the head cannot be readily removed or interchanged with other types of heads.
U.S. Pat. No. 3,360,286 discloses another articulating mop head. Here, both the pivot and swivel action of a universal joint are controlled by nut and fastener connections. By loosening one or both of these connections the mop head can pivot and/or swivel with varied degrees of rigidity depending upon the looseness of the connections. Tightening each connection can prevent either or both of the articulating movements. This device has several shortcomings as well, for example, tools or a strong hand may be necessary to adjust the head and there are no preset centering or angular positions for the head to be moved into quickly. And again, the head is not readily removable or interchangeable.
U.S. Pat. No. 6,301,740 discloses a disposable brush having an extension handle. This device is not designed to articulate during use, however, it does provide for adjustment of the angular position of the head relative to the handle. Loosening a thumb screw loosens the engagement of one or more projecting ribs with surfaces of the handle to allow the head to be rotated. Once adjusted the thumb screw is retightened to hold the head in the new position. The ribs help prevent unintended rotation of the head during use, however, like they do not provide for quick re-positioning of the head in one or more discrete angular positions.
U.S. Pat. No. 6,551,001 discloses another type of mop cleaning device with an articulating head mounted via a universal joint type and having an aerosol can which sprays cleaning liquid in front of the cleaning head as the mop is used. It has a snap together assembly that is simple and intuitive, however, the connection is designed to be more permanent in nature once the connection is achieved and it does not provide for pre-set angular adjustments of the mop head.
Additional techniques for adjustably connecting cleaning heads to handles are disclosed in U.S. Pat. Nos. 3,713,744 and 5,926,896. The disclosures of these patents, and all other publications referred to herein, are hereby incorporated by reference as if fully set forth herein.
A need thus still exists for improved articulating connections of a cleaning head to a handle.

Cleaning device with preset lockable swivel head


A prosthesis system consisting of an endoprosthesis with a shank which is to be introduced into the medullary canal of a bone, and of a rasp (20) which is similar in shape to the shank and is used to prepare a cavity for receiving the shank. Along much of its length, the rasp has an untoothed profile part (25) which, instead of excavating the spongy bone substance, compacts the latter and thus ensures a secure fit of the prosthesis. In the area corresponding to the untoothed area of the rasp (20), the prosthesis shank preferably has a rib which cuts like a wedge into the compacted spongy substance.

Endoprostheses are generally connected to the ends of long bones by anchoring a shank of the prosthesis in the cavity of the long bone. If this is to be done without using cement, then, in order to achieve sufficient anchoring stability, there must be substantial correspondence in shape between the prosthesis shank and the bone cavity intended to receive it. For this purpose, a rasp is used whose configuration corresponds with that of the prosthesis shank. After the epiphysis of the bone has been opened, and, if appropriate, after drilling through the epiphyseal spongy substance into the medullary canal of the diaphysis, the rasp is pushed into the bone to the position which the prosthesis shank is intended subsequently to assume. In doing so, the spongy bone is loosened by the rasp action of the instrument and for the most part removed from the bone.
U.S. Pat. No. 4,671,275 discloses a rasp which has an approximately rectangular cross section and is toothed only at the corners. Between these there are smooth, concave surfaces which do not exert any cutting or tearing action, but merely displace the bone material with which they make contact. This avoids the need to pack bone material around the prosthesis shank. The object of the invention is to make available a prosthesis system which consists of prosthesis and rasp and which permits an especially secure fit of the prosthesis shank in the bone. This is achieved by the features of claim 1 and preferably those of the dependent claims.
The invention is based on the observation that the increased strength of that area of the bone cavity generated by the untoothed profile part of the rasp improves the security of the prosthesis fit all the more the closer this area cooperates with the surface of the prosthesis shank. According to the invention, the shank therefore has at least one longitudinal rib arranged in that part of the prosthesis shank corresponding to the untoothed profile part of the rasp. Although it is advantageous for this rib to extend along the entire length of the shank, this is not absolutely essential, as long as a large part of the shank length is involved, preferably greater than one third, particularly preferably greater than two thirds, of the shank length.
The invention recognizes that a particularly secure prosthesis fit is obtained if the abovementioned longitudinal rib of the shank is absent in the profile of the rasp, at least over much of the length of the latter. In this case, the bone cavity created by the rasp in order to receive the shank has no groove at the location where the rib of the shank is situated. Instead, this groove is created only by the shank rib itself. As the shank is being introduced, it cuts like a wedge into the bone material. In this way, a bed is created in the bone cavity for receiving the prosthesis shank, in which bed the prosthesis shank, by virtue of its cross sectional shape, compresses the spongy substance at least in some areas and achieves optimum bone contact, preferably over greater than 70%, more preferably over greater than 80% of the shank surface.
The effect achieved according to the invention is further increased if the untoothed profile part of the rasp is dimensioned smaller than the corresponding part of the shank, with the result that, after implantation of the prosthesis shank, the surface of the bone cavity surrounds the latter with prestressing.
The invention is of particular importance for anchoring of a hip prosthesis which is to be implanted without cement. If the shank of the hip prosthesis is curved in approximation to Shenton""s line, the untoothed profile part should be arranged on the ventral and/or dorsal aspect of the rasp, preferably on both aspects, while the rasp is toothed at least on the medial aspect. In this way, the surface of the bone cavity can be adapted very precisely to the surface shape of the shank in the medial area. First, this is important because the bone surface is fairly irregular there. Second, a relatively close approximation of the shank surface to the hard cortical bone is desired here. Thus, the remaining spongy layer, where the cortical bone has not been reached directly, is already comparatively compact and gives little play for compaction of the spongy bone substance, so that, in areas where pressure is too great, there is a risk of the cortical bone bursting if one were to rely solely on displacement of the spongy substance. For this reason, the toothing on the medial aspect of the rasp should be provided at least in the proximal area thereof. That means a section of about 4 to 7 cm in length on the medial aspect of the shank, measured from the upper end of the shank. The lateral aspect of the rasp is also expediently toothed, at least in the proximal section thereof.
By contrast, it is expedient if the distal section of the rasp is designed without sharp transverse edges on the medial and lateral aspects. This is because it is intended to fulfil a guide function, upon insertion of the rasp into the bone, by means of sliding along the inner surface of the cortical bone, primarily in the diaphyseal area, the aim of this being to avoid unnecessary damage to said cortical bone.
The untoothed areas on the ventral and/or dorsal aspects of the rasp preferably extend along the entire length of the rasp. Both aspects can be provided with the abovementioned longitudinal rib, which likewise is preferably arranged running along essentially the entire length of the shank. It is particularly advantageous if this rib is formed by a pair of grooves enclosing it on both sides, by which means a large contact surface is created for the intimate contact between the prosthesis shank and the compacted bone material. If this rib is absent in the rasp profile, only the groove cross sections are formed thereon, their bottom surfaces being connected essentially directly to each other. This creates, on the ventral and dorsal aspects of the rasp, extensive surfaces which are expediently spaced apart from each other by a distance which increases in a wedge shape from the direction of the distal end, in order to gradually compact the bone material along which the rasp slides as it is being pushed into the bone.
The concept of the invention can be summarized by stating that a prosthesis system consisting of prosthesis and rasp is made available which, in order to create the cavity for receiving the prosthesis, does not require prior excavation of bone material, but instead leaves the bone material in situ, and with which, by means of marked differences in shape between rasp and prosthesis shank, the spongy bone substance is compressed, upon insertion of the prosthesis shank, in such a way that an exercise-stable and secure fit of the prosthesis is achieved with high vital form closure to the bone.


Provided are a shift register unit and driving method thereof, a gate driver and a display device, the circuit configuration of the shift register unit can be simplified by disposing, in the shift register unit, the signal input unit for outputting the first level signal or the second level signal to the first terminal of the latch unit under the control of the input signal and the reset signal, the latch unit for latching the signal input from the signal input unit and outputting the latched processed signal to the pull-down unit, the pull-down unit for outputting the first level signal or the second level signal to the signal output unit under the control of the latched processed signal, and the signal output unit for receiving and inverting the signal output from the pull-down signal to generate an output signal and outputting a signal being opposite to the output signal, which is helpful for achieving the narrow bezel of the display panel.

A shift register unit used in a conventional low temperature poly-silicon technology adopts D flip-flops constituted by an inverter, a NAND gate and a transmission gate, and usually comprises two D flip-flops. An output signal is latched by the D flip-flops, and the transmission and shift of the signal is controlled by a clock signal.
For a typical existing shift register, it is mainly constituted by two D flip-flops, and its operation principle is as follows: when a first D flip-flop is switched on by a clock pulse of the clock signal, the level signal input from a previous stage of unit enters into the first D flip-flop, but the level signal cannot enter into a second D flip-flop since the transmission gate at the front end of the second D flip-flop is switched off at this time; when a next clock pulse of the clock signal comes, the first D flip-flop is switched off and latches its input signal (that is, the level signal), the second D flip-flop is switched on at this time, and the input signal enters into the second D flip-flop and is output by the second D flip-flop. Thereby, the shift operation of the level signal from a previous stage of unit to an adjacent next stage of unit can be achieved.
Since the implementation of the D flip-flop includes two transmission gates, an inverter and a NAND gate, and a conventional shift register requires two D flip-flops, the conventional shift register unit has the disadvantages that a lot of gate circuits are used, the circuit configuration is too complex, a large layout space is required, all of which is not helpful for achieving a narrow bezel of a display panel, although the conventional shift register unit is classic.

Shift register unit and driving method thereof, gate driver and display device

CHENGDU BOE OPTOELECTRONICS TECHNOLOGY CO., LTD.


A method and an apparatus for detecting, locating, and quantifying contamination in a fluid flow system like a pipe or duct. This characterization technique uses a conservative and one or more interactive tracers that are injected into the fluid flow system and then monitored at another location in the system. Detection, location, and quantification are accomplished by analysis of the characteristic features of measured curves of tracer concentration.

1. Field of the Invention
A method and an apparatus for characterizing contaminants of interest in a fluid flow system like a pipe, duct, or channel using interactive tracers. Various types of interactive tracers may be used, including reactive and partitioning tracer gases and liquids. The method works on fluid flow systems using gaseous tracers in which the liquid contents have been removed or are partially removed. The method will also work for fluid flow systems that filled or partially filled with a liquid. The tracers are selected to detect, locate, and measure the concentration of specific contaminants of interest. These contaminants may accumulate as a liquid, film, residue, or particulate build-up on the walls of the system, in low elevation points, or at appurtenances and geometric constrictions or flow constrictions. This method has application for characterizing contamination in pipe and ducts that once contained chlorinated solvents, petroleum products, radioactive materials, heavy metals or other types of hazardous substances and hazardous waste. This invention has immediate application for decontamination and deactivation (D&D) activities at the U.S. Department of Energy's (DOE's) nuclear sites, such as the Hanford Site, and various industrial and petroleum facilities. This invention also determines when the decontamination operations have been successfully completed.
2. Brief Description of Prior Art
Within the U.S. Department of Energy (DOE) inventory, there are several thousand miles of piping and ductwork from facilities throughout the United States that are ready for deactivation and decommissioning (D&D). A similar problem exists in industrial and chemical/petroleum facilities that are taken out of service for closure or for maintenance and cleaning. These piping systems have been used to move various types of contaminated fluids (liquids and gases) from one area to another within a facility. The ductwork moved air within the facilities through ventilation systems. Over the course of the operation of these facilities, these passageways have become contaminated with the residual hazardous and radioactive materials that they transported. Chorinated solvents such as trichlorethylene (TCE) and carbon tetrachloride (CCl4) which were used as degreasers at many industrial complexes both within the DOE and the Department of Defense (DOD) facilities, are an examples. Many of the piping systems or large sections of piping are inaccessible and external inspection techniques that require access to the outside wall of the pipe cannot be used. Many of the pipes are buried underground, or are located beneath the floor of a building or beneath paved areas. Because direct access to the external pipe wall is not frequently possible, methods that involve internal inspection of the pipe need to be used. These methods generally require that any liquid in the pipe be removed before the inspection method can be applied.
A common measurement approach for determining whether or not a pipe of duct is contaminated is to use a camera to inspect the inside of the pipe. For short sections of pipe, a small camera is inserted into the pipe on a cable. For example, in U.S. Pat. No. 6,359,645, Sivacoe describes a method of inspecting a pipe, by pushing a video camera through the pipe on a cable. In U.S. Pat. No. 5,939,679, Olsson describes an electromechanical system for inspecting the inside of pipes over distances of several hundred feet for defects and obstructions using a push-cable that mechanically and electrically connects a video camera head to a push reel and video circuit. In addition to cable-inspection systems, a "pig" can be inserted into the pipe to inspect the pipe wall for integrity over the entire length of the pipe. In U.S. Pat. No. 6,243,657, Tuck, et. al., describes a pipe wall inspection system using a pig having an inertial measurement unit and a magnetic sensing system for finding wall anomalies.
A camera and other pipe inspection sensors can be mounted on a robotic vehicle, which is inserted into the pipe and allowed to move down the pipe. For example, in U.S. Pat. No. 6,427,602, Hovis, et. al., describes a crawler for inspection of the integrity of 3- to 4-in. diameter piping, where the crawler can carry sensors or a camera to perform the inspection. This approach is acceptable for larger diameter piping, but for small piping, the robotic vehicle may be too large to be used or not be able to move past bends and constrictions in the pipe. The robotic vehicle can be instrumented with a camera, chemical sensors, and sample collectors. Where access to the pipe is possible, the pipe is sometimes cut and analyzed for contamination in the laboratory.
In general, most methods of finding contamination require the insertion of a physical device into the pipe such as a cable, crawler, or pig. There are many nondestructive pipe inspection techniques, some of which are added to these physical delivery systems, and some of which propagate down the pipe. Most of these methods and apparatuses involve the use of nondestructive testing techniques such as eddy current, ultrasonic, and magnetic flux sensing technologies and all of these technologies involve assessing the integrity of the wall of the pipe, not finding contamination in the pipe.
As DOE begins decontaminating and decommissioning of their facilities, innovative methods to determine the type and level of contamination that is present in the pipe and ductwork are needed for cost-effective and safe D&D operations. DOE has been seeking methods that improve the cost, efficiency, effectiveness and safety of these activities. Non-invasive or minimally invasive methods are sought.
The method of the present invention uses tracers to characterize the contamination in the pipe, where at least one of the tracers does not interact with the contaminant of interest in the pipe, and one or more tracer do. Tracers have been used for characterizing subsurface contamination between monitoring wells such as Dense Non-Aqueous Phase Liquids (DNAPLs), Non-Aqueous Phase Liquids (NAPLs), and Light Non-Aqueous Phase Liquids (LNAPL's) such as unleaded gasoline and diesel. Such methods have been used in both the saturated zone using the natural groundwater flow at the tracer carrier fluid or in the vadose zone using an established air flow field as the tracer carrier. In U.S. Pat. No. 6,321,595, Pope, et. al., teaches a method of characterization of organic contaminants in subsurface formations such as nonaqueous phase liquids by injecting partitioning and non-partitioning tracers at one well point and measuring the arrival times of these tracers at another well point. This subsurface tracer approach has also been used to detect releases of a hazardous liquids from underground and aboveground storage tanks. While none of these approaches have been used to identify the presence of contamination inside a pipe or a duct, these methods have identified a variety of partitioning tracers that can be used in the method of the present invention for characterizing contamination in fluid flow systems such as pipe and ducts, which in many instances is the source of the subsurface contamination.
Various tracer methods have also been used for detecting and locating a hole in a tank or a pipe, but none of these methods are used to find contamination in the tank or pipe.
There are a number of important advantages of the method of the present invention over the physical delivery systems currently used for characterizing contamination in pipe and ductwork. The first advantage of the proposed invention is that the same procedure will work on pipes (or ducts) of any size and nearly any length. Tracers are just as easily injected into a small diameter pipe (e.g., 0.5 in.) as they are into larger diameter pipe (e.g., 12 in.). Other remote pipe inspection equipment, which transport cameras by crawlers into a pipe, require pipe diameters of 4 in. or larger for entry and operation. Many of the pipelines within building systems are on the order of 0.5 to 2.0 inches, making inspection using cameras nearly impossible.
The second advantage of the proposed invention is that the injected tracers can easily navigate pipe (or duct) bends and other pipe irregularities with ease compared to remotely operated inspection equipment. Tight bends and changes in diameter are not a problem for the tracer gases, yet represent major hurdles for other characterization techniques. Gas tracers also inspect the entire surface of the pipe, including any crevices or nooks that may be difficult to inspect using video approaches. This will result in a more complete and thorough inspection of the pipe (or duct).
The third advantage of the proposed invention is that there are no moving parts or equipment that has to enter the pipe. For pipes or ducts that may contain explosive vapors or contaminants that could ignite, the partitioning tracer technique offers a characterization approach that remains safe. In addition, since no mechanical equipment enters the pipe, this eliminates the possibility of equipment malfunction or getting "stuck" and "plugging" the pipe (or duct).
The fourth advantage is that equipment contamination and de-contamination is avoided. This has both safety and cost implications. Because no equipment enters the pipe, there is no equipment that must be decontaminated when it exits the pipes. This reduces the amount of investigation-derived wastes that need to be disposed of properly.
The fifth advantage of the proposed invention is that it can be operated more cost effectively and more safely than other techniques without sacrificing performance. In fact, the performance of the proposed invention should be better than the more conventional methods.
In addition to being a very advantageous approach for the end users, the proposed invention can also be used in a variety of detection and measurement scenarios. The most common scenario is to characterize a pipeline or duct system to determine if the pipeline has any residual contamination that must be removed before the pipe or duct can be decommissioned or released. The proposed invention can also be used before and after a decontamination event to validate the amount of contamination that has been removed from the pipeline by a particular decontamination technology. Finally, the proposed invention can also be used to routinely monitor pipelines and ductwork to monitor any residual buildup of contaminants that could reduce efficiency of the pipeline.
The method described is motivated by the D&D need. As a consequence, it is described in terms of gaseous tracers, because in most D&D activities, all of the liquid contents of the pipe are removed before any attempt to clean the pipe is done. Cleaning is typically done by flushing the pipe with water or some other cleaning chemical. The liquid used to flush the pipe is removed before any attempt to determine if any residual contamination exists. With properly selected interactive tracers, the method of the present invention can be applied using either gaseous or liquid tracers.

This patent is subject to a terminal disclaimer.

Method to detect and characterize contaminants in pipes and ducts with interactive tracers


A RC power semiconductor is provided which comprises a plurality of diode cells and a plurality of GCT cells. Each GCT cell comprises a first cathode layer with at least three cathode layer regions, which are separated from each other by a base layer. In orthogonal projection onto a plane parallel to the first main side each one of the cathode layer regions is strip-shaped and a width (w, w′), wherein the diode cells alternate with the GCT cells in a lateral direction in at least a mixed part, wherein in each GCT cell, the width (w′) of each one of the two outer cathode layer regions next to a diode cell neighboring to that GCT cell is less than the width (w) of any intermediate cathode layer region between the two outer cathode layer regions in that GCT cell.

A known power semiconductor device is the integrated gate commutated thyristor (IGCT) which includes one or more gate commutated thyristor (GCT) cells within a single wafer. Each of the GCT cells is made up from a cathode electrode in form of a cathode metallization layer, an n+-doped cathode layer, a p-doped base layer, an n−-doped drift layer, an n-doped buffer layer, a p+-doped anode layer and an anode electrode in form of an anode metallization layer. The GCT cells also include a gate electrode in the form of a gate metallization layer which is in contact with the doped base layer. The gate metallization layer is arranged in a plane which is below the plane in which the cathode electrodes are arranged in order for the gate metallization layer to be separated from the cathode electrodes. The IGCT includes at least one gate contact in the form of an annular metallic region either in the centre of the wafer, at the perimeter of the wafer or somewhere in between. The gate contact region is in direct contact with the gate metallization layer so that the gate contact region and the gate electrodes of all GCT cells are connected electrically and thermally with each other.
Another known power semiconductor device is the reverse conducting integrated commutated thyristor (RC-IGCT) which includes within one single wafer an IGCT part and a single built-in freewheeling diode part. The freewheeling diode part is made of one single diode including a p-doped anode layer and an n+-doped cathode layer, which are separated by the n−-doped drift layer and the n-doped buffer layer. The diode is arranged adjacent to the IGCT part in such a way as to either be in the innermost or outermost region of the wafer. Between the IGCT part and the freewheeling diode part there exists an n−-doped separation region which separates the p-doped base layers of the GCT cells in the IGCT part from the p-doped anode layer of the diode.
In FIGS. 1 and 2 there is shown a power semiconductor device known as the bi-mode gate commutated thyristor (BGCT). FIG. 1 shows the device in top view and FIG. 2 shows the device in cross section taken along line c′-c in FIG. 1. The BGCT is similar to the RC-IGCT and comprises in a single wafer 1 a plurality of gate commutated thyristor (GCT) cells 2 electrically connected in parallel to one another. The GCT cells 2 in the BGCT are identical to the GCT cells found in the RC-IGCT. In the BGCT shown in FIGS. 1 and 2 each of the GCT cells 2 is made up from three cathode electrodes 3 in form of a cathode metallization layer, an n+-doped cathode layer comprising three strip-shaped cathode segments 4, a p-doped base layer 5, an n−-doped drift layer 6, an n-doped buffer layer 7, a p+-doped anode layer 8 and an anode electrode 9 in form of an anode metallization layer. Like in the IGCT, the GCT cells 2 also include a gate electrode 10 in the form of a gate metallization layer which is in contact with the doped base layer 5. The gate metallization layer is arranged in a plane which is below the plane, in which the cathode electrodes 3 are arranged, so that the gate metallization layer is separated from the cathode electrodes 3. The BGCT includes one single gate contact 11 in the form of an annular metallic region in the centre of the wafer 1. The gate contact 11 is in direct contact with the gate metallization layer so that the gate contact 11 and the gate electrodes 10 of all GCT cells 2 are connected electrically and thermally with each other.
In contrast to the RC-IGCT the BGCT comprises not only a single freewheeling diode part with a single diode but a plurality of diode cells 12 distributed between the GCT cells 2. The diode cells 12 are electrically connected in parallel to one another and to the GCT cells 2, albeit with opposing forward direction. Each diode cell includes an anode electrode 17, a p-doped anode layer 13 and an n+-doped cathode layer 14, and a cathode electrode 16, wherein the p-doped anode layer 13 and the n+-doped cathode layer 14 are separated by the n−-doped drift layer 6 and the n-doped buffer layer 7. Neighbouring GCT cells 2 and diode cells 12 are separated by multiple separation regions 15.
FIG. 3 shows a cross section of a modification of the BGCT shown in FIG. 2, in which in the GCT cell 22 cathode segments 4 that lie in the immediate proximity of a diode cell 12 are surrounded by a gate electrode 20 from all sides. In this case the separation region 15 is laterally spaced from the next cathode segment 4 by a greater distance than in the embodiment shown in FIG. 2 as a wider base layer is required to have enough space for the portion of the gate electrode 20 which is arranged between the separation region 15 and the adjacent cathode segment 4, respectively. Elements in FIG. 3 having reference signs already used in FIG. 2 are identical to the corresponding elements of the device shown in FIG. 2.
The BGCT is disclosed in WO 2012/041958 A2 and in the article "The concept of Bi-mode Gate Commutated Thyristor—A new type of reverse conducting IGCT" by U. Vemulapati et al. in Power Semiconductor Devices and ICs (ISPSD), 2012, pp. 29 to 32, for example.
One of the advantages of the distributed diode and IGCT cells in the same wafer in the BGCT design over the standard RC-IGCT design is the better thermal resistance, because due to the distributed diode cells 12 and IGCT cells 2 the heat is distributed more uniformly in the wafer 1. For example when the BGCT is working in IGCT mode the heat can easily spread from the GCT cells 2 into the diode cells 12. Instead, in the standard RC-IGCTs, the temperature spreads much less efficiently into the diode area because it is concentrated in one continuous area. The same phenomenon is observed when the device is operating in the diode mode.
The maximum controllable current (MCC) and the on-state voltage are important parameters in the above described devices. It is desired to achieve the highest possible MCC and the lowest possible on-state voltage to minimize the losses in the device. Further, uniform turn-on and turn-off are most critical to avoid local overheating.

Reverse conducting power semiconductor device


Polyimide resins that are suitable for processing by resin transfer molding (RTM) and resin infusion (RI) methods at reduced processing temperatures are provided. The inventive RTM and RI processable polyimide resins exhibit melting at temperatures of less than about 200° C. and melt viscosities at 200° C. of less than about 3000 centipoise. A process for synthesizing the inventive resins is also provided, as is a fiber-reinforced composite material. The fiber-reinforced composite material employs the inventive polyimide resin as its resin matrix and demonstrates good heat resistance and mechanical properties.

Fiber-reinforced composite materials, which are made up of reinforcing fibers and matrix resins, are lightweight and have excellent mechanical properties. As such, these composite materials have been widely used in a variety of structural and non-structural applications such as aerospace, automotive, infra-structure repair, marine, military, and sporting goods or other consumer products that must have sufficient toughness and impact resistance to endure many years of harsh service.
Various methods or techniques such as prepreg, hand lay-up, filament winding, pull-trusion, RTM and RI, have been used to produce fiber-reinforced composite materials. Of these methods or techniques, the RTM method, in which a preform made up of reinforcing fibers is placed in a mold, a resin poured therein to impregnate the preform, and the impregnated preform cured to produce a molded product, offers the advantage that a large component having a complicated shape can be molded in a short period of time.
Epoxy resins, and to a lesser extent, unsaturated polyester resins, vinyl ester resins, phenol resins, and polyimide resins, have been employed as matrix resins in fiber-reinforced composite materials. The use of composite materials having polyimide resin matrices is increasing, however, where these materials are now recognized as preferred structural materials in aerospace applications, because of their lightweight and load-bearing characteristics and their oxidative stability at elevated temperatures.
Fiber-reinforced composite materials that use polyimide resins as the matrix resin are generally prepared using prepreg methods. Current technologies for making prepreg and composites from polyimides utilize solutions from the poly(amide) acids of these resins. Poly(amide) acid solutions are processed into prepreg with various reinforcing fibers. These poly(amide) acid solutions are of low solids contents and high viscosity. Therefore, the processing of these types of solutions requires overcoming significant problems such as solvent management and good fiber wet out from the high viscosity solutions. The resultant prepreg typically requires residual solvent contents of 20 to 25% by weight (approximately 2–3% water from thermal imidization reaction) for adequate tack and drape. This residual solvent must then be removed during the composite cure cycle. This material is hand-laid into composites which makes working with this type of material very labor intensive and costly.
The drawbacks inherent in prepreg methods have prompted the development of polyimide resins suitable for processing by RTM and RI methods. The developed resins, however, require relatively high processing and cure temperatures of greater than 250° C., which severely limits their industrial utility due to the need for employing specialized high temperature molding equipment.
For example, Jim M. Criss et al., Resin Transfer Molding and Resin Infusion Fabrication of High Temperature Composites, Proceedings of the 46th International SAMPE Symposium, Vol. 46 (2001), discloses two phenylethynyl containing imide oligomers that are processable by RTM and RI methods. The two oligomers, which are designated PETI-RTM and RFI, reportedly display low and stable melt viscosities at temperatures of 250 to 290° C. PETI-RTM is defined as BPDA//25 mole % 3,4′-ODA/75 mole % APB//PEPA, having a Mn=750 g/mole, while PETI-RFI is defined as BPDA//25 mole % 3,4′-ODA/75 mole % APB//PEPA, having a Mn=1250 g/mole. Composites are prepared by RTM using the PETI-RTM and PETI-RFI oligomers and by RI using the PETI-RFI oligomer, at processing temperatures of greater than 250° C. The injection temperature used was in the range of 260 to 288° C., while the cure temperature was 371° C.
U.S. Pat. No. 5,965,687 to Brian J. Jensen discloses mixtures of polymeric materials consisting of branched, star-shaped and linear polyimides, which are synthesized by using a small yet critical amount of a trifunctional monomer (e.g., a slow-reacting triamine such as triamino pyrimidine or melamine), along with the conventional difunctional monomers in the polymerization. These mixtures reportedly have lower melt viscosities than linear polymers at the same molecular weight thereby allowing for processing via RTM or RFI at lower pressures and temperatures with techniques such as autoclave processing. See Col. 2, lines 51 to 55, of U.S. Pat. No. 5,965,687. Processing temperatures of greater than 250° C. are still required, however, thereby limiting the industrial utility of these mixtures.
U.S. Pat. No. 6,124,035 to Connell et al. discloses high temperature transfer molding resins prepared from aromatic diamines containing phenylethynyl groups and various ratios of phthalic anhydride (PA) and 4-phenylethynyl phthalic anhydride (PEPA). These resins reportedly have, among other things, relatively low melting temperatures (˜182° C.), low melt viscosities (<1 poise at ˜270° C.), and excellent melt stabilities (>2 hours at 250˜280° C.). As noted above, however, the relatively high temperatures that are required to process these resins severely limit their industrial utility.
A need therefore exists for a polyimide resin for use as a matrix resin in a fiber-reinforced composite that possesses properties rendering it suitable for processing by RTM and RI methods at reduced processing temperatures.
It is therefore a primary object of the present invention to provide such a resin.
More particularly, it is an object of the present invention to provide polyimide resins that may be processed at reduced processing temperatures, and that exhibit melting at temperatures of less than about 200° C. and melt viscosities at 200° C. of less than about 3000 centipoise.
It is another object of the present invention to provide a process for synthesizing such RTM and RI processable polyimide resins.
It is a further object to provide a fiber-reinforced composite material that employs such a polyimide resin as the matrix resin and that has good heat resistance and mechanical properties.