Disclosed are compositions, methods, and kits for treating conditions including; ameliorating side effects associated with compounds such as lipase inhibitors; gastrointestinal distress; fecal urgency; obesity; hyperlipidemia; diarrhea; reducing levels of toxic substances; reducing blood cholesterol levels; inducing satiety; effecting weight loss; effecting weight control; and treating, delaying onset and/or preventing Type II diabetes. One embodiment includes compositions for administration to an animal for stiffening lipophilic substances in the gastrointestinal tract. Such stiffening agents have a complete melting point of about 33° C. or greater. Kits comprising the composition are also included. Methods of stiffening lipophilic substances present in the gastrointestinal tract of an animal are also provided. The methods comprise administering a composition comprising a safe and effective amount of a stiffening agent to an animal. The methods also comprise administering a composition comprising a safe and effective amount of a stiffening agent and a safe and effective amount of a lipase inhibitor to an animal.

A significant portion of the American population is considered to be obese, with an even larger portion of this population considered to be overweight. Obesity is also considered to be a growing problem in other industrialized countries and in developing countries where large numbers of people have become accustomed to Western-influenced high-caloric diets. It has been estimated that obesity contributes to 50% of chronic diseases in Western societies and is responsible for approximately 70% of preventable deaths in the United States. Health care costs associated with obesity are substantial. As a result, the development of compositions to effect weight loss is the subject of significant commercial interest.
Approaches to weight control include appetite suppressants, reduced-caloric diets, exercise regimens, inhibition of dietary nutrient absorption (for example, lipids), surgical procedures and the like. A variety of compositions for weight control have been developed. Desired characteristics for such products include the lack of undesirable side effects, high efficacy, convenient dosage regimens, and low cost. Drugs developed to treat obesity may have undesirable side effects, may be available only under medical supervision, and may be relatively expensive. Other products such as those with high fiber content may require inconveniently large doses to be effective.
One method of inhibiting the absorption of dietary lipids is by inhibiting digestion and/or metabolism of these lipids via administration of a suitable non-absorbable material to bind or sequester the lipids. For example, U.S. Pat. No. 4,223,023, Furda, issued Sep. 16, 1980, describes the ingestion of chitosan to bind fatty acids and prevent their utilization. Similarly, U.S. Pat. No. 5,453,282, Kanauchi et al., issued Sep. 26, 1995, describes dietary lipid absorption-inhibiting agents comprising a mixture of chitosan and ascorbic acid or a salt thereof. However, the efficacy of chitosan in increasing fat excretion is relatively low, requiring impracticably large doses to be effective as a dietary weight-control supplement. (See, for example, Lengsfeld et al., Obesity Research, Vol. 7, Suppl. 1, November 1999). Certain fat-imbibing polymer particles are described in U.S. Pat. No. 4,432,968 Page et al., issued Feb. 21, 1984. Fat-binding polymers are also described in WO 99/34787, Mandeville et al., published Jul. 15, 1999. Similarly, U.S. Pat. No. 3,980,968, Ingleman et al., issued Sep. 14, 1976, describes certain solid network (i.e., crosslinked) polymers containing amino groups for binding bile acids. Solid crosslinked polyurethane polymers which form a gel in the presence of water and which are capable of binding cholesterol and lipids have been described as in U.S. Pat. No. 4,340,699, Grouiller, issued Jul. 20, 1982.
Another approach to inhibiting the digestion and/or metabolism of dietary lipids is to utilize compounds that inhibit the activity of certain enzymes necessary for digestion of lipids. Polymers which inhibit the action of pancreatic lipase are described in U.S. Pat. No. 3,923,976, Fields and Johnson, issued Dec. 2, 1975 and U.S. Pat. No. 4,211,765, Johnson and Fields, issued Jul. 8, 1980. However, the efficacy of these materials in inhibiting lipid digestion is also low, as measured by fat excretion.
Other lipase inhibitors can reduce the digestion of fat and oil, thereby causing the elimination of unabsorbed fat and oil through the feces. Examples of lipase inhibitors include tetrahydrolipstatin (orlistat; XENICAL®) described in U.S. Pat. No. 4,598,089, Hadvary et al., issued Jul. 1, 1986; lipase inhibitors including 2-amino-4H-3,1-benzoxazin-4-one and its derivatives described in WO 0040247 published Jul. 13, 2000; 2-oxy-4H-3,1-benzoxazin-4-ones and its derivatives described in WO 0040569, published Jul. 13, 2000; 2-thio-4H-3,1-benzoxazin-4-one and its derivatives described in WO 0153278, published Jul. 26, 2001; teasaponin described in Han et al., Int. J. Obes. Relat. Metab. Disord., Vol. 25, pp. 1459-1464, 2001; long-chain alpha-keto amides described in Chiou et al., Lipids, Vol. 36, pp. 535-542, 2001; extract of Nomame Herba described in Yamamoto et al., Int. J. Obes. Relat. Metab. Disord., Vol. 24, pp. 758-764, 2000; chiral alkylphosphonates described in Cavalier et al., Chem. Phys. Lipids, Vol. 100, pp. 3-31, 1999; chiral isomers of beta-lactone described in Tomoda et al., Biochem. Biophys. Res. Commun., Vol. 265, pp. 536-540, 1999; and Pluronic L-101 described in Comai et al., Int. J. Obes., Vol. 4, pp. 33-42, 1980.
However, anal leakage of undigested oil is an adverse side effect often observed in subjects treated with sufficiently large doses of lipase inhibitors to be effective in the treatment of obesity. Several approaches have been described to ameliorate this side effect. Combining a lipase inhibitor with substantial amounts of water-insoluble crude fiber to increase the inhibition of fat absorption is described in U.S. Pat. No. 5,447,953, Isler et al., issued Sep. 5, 1995. Combining a lipase inhibitor with certain poorly digestible, poorly fermentable hydrophilic, hydrocolloidal food grade thickeners, or emulsifiers to reduce anal leakage is described in WO 00/09122, Hug et al., published Feb. 24, 2000. Similarly, combining a lipase inhibitor with chitosan or a derivative or salt thereof to reduce anal leakage is described in U.S. Pat. No. 6,030,953, Bailly et al., issued Feb. 29, 2000. However, at convenient dosage levels, the efficacy of such materials in eliminating anal leakage is relatively low, as evidenced by significant levels of oily fur greasing in rodents.
As described above, the use of effective doses of agents that inhibit certain enzymes necessary for the digestion and absorption of fats and oils can lead to significant undesirable symptoms. Known materials that sequester or bind dietary lipids typically have low efficacy, requiring inconveniently large doses to be effective in the prevention or treatment of obesity, or in ameliorating the side effects associated with certain drugs, laxatives and fat-substitutes.
Accordingly, it would be desirable to develop a composition useful for treatments such as weight control that: (1) is suitable for ingestion; (2) has minimal undesirable side effects; (3) has high efficacy; (4) has convenient dosage regimens; and (5) is broadly applicable to various lipids, lipid substitutes, and other lipophilic substances.

Compositions, methods, and kits useful for the alleviation of gastrointestinal effects


An intersection communications system includes a vehicle intersection traffic movement indicator; a traffic movement surface indicator positioned behind an edge of the vehicle traffic intersection; a pedestrian lane surface indicator; one or more traffic direction surface indicators positioned within the vehicle traffic intersection; and a communications server configured to transmit a first signal to a first traffic movement surface indicator when a first monitored event occurs, transmit a second signal to a first right-turn traffic direction surface indicator directing the first vehicle to turn right from a first street to a second street when a second monitored event occurs, transmit a third signal to a second left-turn traffic direction surface indicator directing the first vehicle to turn left from the first street to the second street when a third monitored event occurs, and transmit a fourth signal to the pedestrian lane surface indicator when a fourth monitored event occurs.

A vehicle traffic intersection involves multi-directional flow of numerous vehicles, as well as numerous pedestrians in urban and suburban areas. A driver's attention is required to focus on many activities simultaneously, ranging from the current state of a traffic signal, vehicles turning into the driver's path, vehicles changing lanes into the driver's path, and pedestrians attempting to cross a street in front of the driver's path.
Traffic signs, signals, and pavement markings attempt to provide safe and smooth vehicle travel through a vehicle traffic intersection. However, many traffic accidents still occur at vehicle traffic intersections. Some of the pavement markings are difficult to see until the driver is very close to the markings. Pavement markings also become faded with time. In addition, pavement markings can be difficult to see during low visibility times, such as periods of rain, snow, and fog, as well as nighttime periods.
The "background" description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description which may not otherwise qualify as conventional at the time of filing, are neither expressly nor impliedly admitted as conventional against the present disclosure.

Intersection communication systems and methods


An incremental integrator integrates a signal from a previous time to the present time to obtain an average value for the signal. An input signal is applied to an analog integration circuit which performs a continuous integration of the input signal. A time delay circuit delays the output of the integration circuit for a time period equal to that of a sampling clock. The output of the delay circuit as well as the output of the integration circuit are applied to a differential amplifier. A sampling circuit samples the output of the differential amplifier so as to give a value equal to the integral for a period equal to the delay circuit period at the time the signal was sampled.

The present invention relates generally to electronic integrator circuits, and more specifically to an incremental integrate and dump circuit.
Electronic integrator circuits are devices which produce an electronic output signal which is proportional to the integral of the input signals that they receive. Such devices have digital applications in analog-to-digital converters. In such applications, the integrator circuit approximates the mathematical process of integration.
It is often desired to integrate a signal from a previous time, (t-T). to the present time, t, in order to get an average value for the time period, (t-T). This previously has been done by using an integrate and dump circuit. An integrate and dump circuit generally consists of the charging of a capacitor through a resistor end of the period then discharging or dumping the charge on the capacitor to start the next period.
The prior art integrators, as described above, are simple, but require dump circuits to discharge the capacitor after each cycle of use. High speed electronic applications can require the use of integrators over very short periods ranging from 10 to 1,000 nanoseconds. In such applications, it is very difficult to dump the charge on the capacitor of the integrator
The task of providing a high speed incremental integrator is alleviated, to some extent, by the systems disclosed in the following U.S. Patents, the disclosures of which are incorporated herein by reference:
U.S. Pat. No. 4,030,038 issued to Daniel et al.;
U.S. Pat. No. 3,767,899 issued to L. Barter;
U.S. Pat. No. 3,906,214 issued to R. Hess;
U.S. Pat. No. 4,020,363 issued to S. Numata et al; and
U.S. Pat. No. 4,278,943 issued to E. Basuda et al.
All of the above-cited disclose integration circuits. Of particular note is the system of U.S. Pat. No. 4,030,038 which discloses an integrator circuit having several periodic dumping integrators all sharing the same analog-to-digital converter. U.S. Pat. No. 3,767,899 discloses a digital integrator for evaluating operator selected portions of analog chart traces. U.S. Pat. No. 3,906,214 discloses a signal retaining integrator having the capability of maintaining a reference voltage required for precision integration.
While the systems disclosed in the above-cited references are instructive, the need remains to provide an incremental integrator circuit which outputs a time-averaged value of an analog signal over short intervals without requiring a dump circuit to discharge the integrator. The present invention is intended to satisfy that need.

The United States of America as represented by the Secretary of the Air Force


A multi-functional shading device includes a first shading arrangement including a top traverse supporter adapted for affixing to a top beam of a ceiling, a first shading arrangement downwardly extended from the top traverse supporter including a base member and a first operating means for selectively lifting up the base member towards the traverse supporter and unlifting the base member to drop downwardly away from the traverse supporter, a second shading arrangement including a base stabilizer, a translucent fabric, which is folded in a Z-shaped manner, downwardly extended from the base member to the base stabilizer, a second operating means for folding and unfolding the translucent fabric, and a pair of windproof arms disposed on two sides of shading arrangements for restricting shading device from swaying back and forth. Therefore, the first and second shading arrangements having different light intensity blooding abilities are adapted for selectively blocking lights passing through from one side to another side of the shading arrangements respectively.

1. Field of Invention
The present invention relates to window curtains, and more particularly to a multi-functional shading device which is adapted for selectively shading the intensity of sunlight.
2. Description of Related Arts
Curtains and the like such as drapes and portieres are commonly used for sheltering window, separating spaces, and etc since they are easy to open and close, and aesthetically appealing. Most of the curtains comprise a traverse supporter adapted to be affixed to a ceiling, a slider track mounted on a bottom of the traverse supporter, and a plurality of slates horizontally and suspendedly mounted by hanging strings respectively in such a manner by operating a pulley system, the slats are slid in a vertical movable manner, or individually rotated at the same time.
However, the curtain has several drawbacks. When the curtain is opened, the house will be exposed directly to an excessive amount of sunlight which not only can heat up interior air of the house but also unpleased people's eye. On the other hand, when the curtain is fully closed, sunlight will be definitely blocked. So, people in the house, with no options, have to turn on the light lamp to brighten up the house. Furthermore, people has not privacy at all since when the curtain is fully opened, the inside scenery of the house is easily viewed from outside so that people may either close the curtain for privacy and security or open the curtain to enjoy the sunlight.
Therefore, draperies, an alternative method for blocking the sunlight, have been used for translucent window curtain. The drapery, usually made of lightweight woven, could provide decorative effects and satisfied privacy for people because the drapery is semi-transparent that people from outside can not view the interior scenery through the translucent window. Moreover, the drapery can partially block the sunlight so as to soften the sunlight.
However, the above mentioned blinding devices, such as curtains and drapery, are not adapted to be used under a strong windy circumstance. Since there are no wind-proof functions embodied, the strong wind would cause curtains and draperies sway back and forth with an annoying noise. Even worse, the swaying blinding devices sometimes would hit the objects positioned close to the window. Especially, drapery is soft and lightweight, so the wind can easily blow it to sway creating undesirable light effects and even an embarrassing "flying" drapery.


A screen printing machine includes a supporting member, a printing mechanism, and a spraying mechanism. The supporting member includes a supporting surface, a number of cavities defined in the supporting surface to receive a number of substrates, and a number of screens detachably covering the plurality of cavities. The printing mechanism includes a guide plate located above the screens, a sliding device slidably connected to the guide plate, a roller rotatably connected to the sliding device, and a squeegee. The sliding device is configured to drive the roller to roll across and the squeegee to slide across the screens. The spraying mechanism is located at one side of the supporting member for dispensing printing material onto the press roller.

1. Technical Field
The present disclosure relates to a screen printing machine for printing images on a number of substrates.
2. Description of Related Art
Screen printing is a method of printing images on substrates using a screen with a number of mesh openings. Some mesh openings of the screen are filled with impermeable substance, and the remaining mesh openings form a stenciled pattern. The ink is forced through the empty mesh openings by a squeegee, thereby forming an image corresponding to the stenciled pattern onto the substrate. Although conventional screen printing machines satisfy basic requirements, a new type of screen printing machine is still needed.


A user interface system, including a user device. The user device includes a processor, a display that interacts with the processor to display a user interface including a site content and a first interactive object. The processor is operative to expand the first interactive object and transform the first interactive object to a content object displayed on the display, when a user touches and holds the first interactive object for a predetermined period of time. The processor is also operative to terminate, contract, and transform the content object for the display to display a second interactive object, the second interactive object having a secondary content trigger, upon the user releasing the holding of the first interactive object after the predetermined period of time.

Link-based advertising is used to generate interest and traffic to websites and other similar platforms. Generally, a banner ad is displayed on a page/app that is being experienced by a user. The banner ad includes graphics/information intended to entice the user to select the ad, generally by clicking/touching the banner itself, which then opens a website/app associated with the banner ad for further engagement.
Various types of advertising exist online, including but not limited to: pop up ads, banner ads, native ads, bumper ads, video ads, expandable ads, and interstitial ads. These ads allow for third parties to provide content through websites and applications that are used/visited by users, generally in an effort to entice those users to interact with the third party's own website or application. When selected these ads generally open a new page/application, sometimes taking the user away from their originally desired content and sometimes leaving the original page open but inactive.
Examples of references related to the present disclosure are listed below: U.S. Pat. Nos. 7,647,609; and 8,666,818; and US Patent Application Nos.: 20100223094; 20110288913; 20180185240; 20150193951; and 20120235938.
The related disclosures suffer from a number of disadvantages, including but not limited to failing to provide choice, being susceptible to bot traffic inflating ad analytics, failing to collect data related to attention by users, being limited in freedom, failing to collect accurate information related to user interaction, not providing valuable metrics, not easily tailored for legal compliance, failing to create a secondary economy, not allowing for choice of the user after initial presentation of information, and requiring too much commitment from users on link selection.
What is needed is a system and/or method that solves one or more of the problems described herein and/or one or more problems that may come to the attention of one skilled in the art upon becoming familiar with this specification.

Touch and hold system and method to activate and control mobile content


Apparatus for an improved method for drilling earthen boreholes with a fluid powered rotary motor mounted on the downhole end of a non-rotating, fluid conducting drill string has a fluid powered, axially reciprocating hammer coupled to the motor by means of a rotary coupling having freedom for axial movement, so that the hammer will be rotated by the motor and the motor will be axially isolated from the reciprocating hammer as both are powered by fluid conducted from the surface through the drill string.

The present invention relates to a well drilling tool for use on hollow continuous non-rotating drill strings and in particular to a percussion tool powered by pressurized fluids supplied through the hollow drill string in combination with a generic, fluid powered rotary drilling motor.
Downhole rotary fluid powered drilling motors of several types are in use today and others are being developed for application on non-rotating drill strings in oil well servicing and open hole earth borings. Also, there are a number of different types of surface rotated percussion drills in use today mostly in water-well drilling, blast hole drilling and the like, which have proven to be effective, especially where weight forces on the bit are limited. When downhole motors alone are used on continuous coil tubing strings, weight forces on the drill bit are limited. Also in highly deviated or horizontal wells, bit weight is limited and drill bit penetration rates are consequently reduced.
Downhole percussion tools are presently used on surface rotated drill strings, where the extended length of tubing xe2x80x9cwinds-upxe2x80x9d as a spring, under torsional loading. This quick reacting xe2x80x9cwound-upxe2x80x9d torque discourages axial slip in a splined connection, while at the same time, the elasticity and inertia of the long drill stem soften the sharp hammer blows and would otherwise break loose the static spline friction. Thus, a surface rotary drive is never adequately isolated from the axial hammering of a downhole percussion tool.
Presently several types of fluid powered downhole rotary motors are in use and others are being developed for drilling with non-rotating drill strings. Among these are the Moineau progressive cavity type, such as covered by patents U.S. Pat. Nos. 6,241,494 BI and 4,676,725. Experimental and limited usage motors such as the roller rod vane type of patents U.S. Pat. Nos. 5,785,509, 5,833,444, and 5,302,666 BI are other examples of such downhole motors. Yet other examples are the geared vane and geared turbine type of downhole motors described in Martini U.S. Pat. No. 6,520,271. For the purposes of this disclosure, all of these drilling motor types are considered generic as related to the present invention.
Therefore, a first object of the present invention is to provide a percussive tool for use in combination with existing gas powered, rotary drilling motors. A second object of the invention is to provide increased drill penetration rates, particularly with non-rotating drill strings and where bit weight is limited and yet a third object is to achieve effective motor isolation from percussive shock.
The present invention is an automatic fluid powered, reciprocating mass, percussion drilling tool adapted to drive a drill bit forward in sustained repetition when coupled with a generic fluid driven rotary motor so as to enhance the drilling operation in accordance to the afore stated objects. The industry is moving to increased usage of fluid powered downhole motors for bit rotation instead of surface drill string rotation and inasmuch as percussion drilling has proven to be effective, the present invention provides a means for adding the benefits of percussion drilling to such pre-existing drill motors.
The apparatus of the present invention provides for an improved method for drilling earthen boreholes with a fluid powered rotary motor mounted on the downhole end of a non-rotating, fluid conducting drill string. The central shaft of a fluid powered, axially reciprocating hammer is coupled to the motor by means of a rotary coupling having freedom for axial movement, so that the hammer will be rotated by the motor and the motor will be axially isolated from the reciprocating hammer. The percussion hammer comprises a reciprocating mass, in the form of an annular piston operating on the central shaft to impact the drilling bit on its down stroke. The motor is powered by fluid conducted from the surface through the drill string according to the well known practice of prior art. In the present invention however, drilling fluid discharged from the motor is utilized at lower pressure for and controlled by valving ports integral to the central shaft so as to power reciprocation of the piston. Upon discharge from the percussion hammer, the drilling fluid circulates through the bit to flush the borehole and carry the cuttings up the annulus around the the drill string to the well surface.
The present invention eliminates the extended drill string length between the surface motor and the percussion tool, so as to eliminate the quick reacting wound-up forces and axial forces which otherwise conspire to inhibit motor isolation. Thus, the percussive blows reach the splined coupling with a sharpness that overcomes static friction in the splines of a connecting coupling coupling and a heretofore unrealized degree of motor isolation is achieved.
Since the output torque and rotational speed of the generic motors varies with the particular design, operational pressure and other factors, the percussion hammer should be sized, tuned and made suitable for the characteristics of each motor as well as the field application. For example a higher speed lower torque output motor would require a relatively light, higher frequency hammer to bit impact while a higher torque lower speed motor could have a higher hammer to bit impact.

Percussion tool for generic downhole fluid motors


The present invention provides a method of coating a packaging container with a coating composition having crosslinkable polyester-polyurethane polymer with at least two carbamate sites, and a crosslinker. The method includes coating a generally planar substrate with the coating composition, curing and forming a container or a portion of a container. The present invention also provides a coating composition and coated substrates.

Coating solutions and coated materials of various kinds are used in the packaging industry. Some coatings serve to protect the exterior layer while some coatings serve as a barrier protecting the contents from contamination by the package itself. In other instances, the coatings are used as decorations or as advertisements. Each coating presents specific requirements at production in order to meet the demand of its intended use. For example, exterior packaging coatings need to be abrasion resistant and if messages are incorporated, the coatings should maintain the properties needed to communicate the information to the intended audience. In some instances, the packaging coating for the exterior of the package should be adaptable to accept other coatings. Other requirements are presented depending on the intended use of the package, such as image retention, weather resistance, and information dissemination.
Interior packaging coatings present other requirements for container packaging. Depending on its intended use, the coated package may be required to meet certain stringent requirements. For example, drug containers must meet very stringent requirements in order to prevent contamination of the drugs. As another example, containers that are used to package edible items such as food, beer and beverage must meet exacting standards. These requirements generally include excellent cure, excellent adhesion of the coating, blush resistance, retort resistance and corrosion resistance.
Most coatings are not formulated to meet these stringent requirements. For example, an automotive coating composition, while useful on a car, may not be useful as a coating for a food or beverage packaging container. It is a fair conclusion, therefore, that not all coatings can be used on package containers for food items.
Another consideration for food and beverage package coatings is cost. An effective coating should be cost effective while meeting the high performance requirements for food and beverage container coatings.
From the foregoing, it will be appreciated that what is needed in the art is a low cost, high performance coating that is easy to make and apply. Such coatings and methods for preparing and applying the same are disclosed and claimed herein.
In one embodiment, this invention relates to novel methods of coating a packaging container. The method of the present invention includes the steps of providing a coating composition having a crosslinkable polyester-polyurethane polymer. The crosslinkable polyester-polyurethane polymer of the present invention preferably comprises at least two carbamate sites. The coating composition preferably also includes a crosslinker.
A suitable method of the present invention includes the steps of: coating on a generally planar substrate; curing the composition; and forming the substrate into a container (e.g., a packaging container) or a portion of a container.
In another preferred embodiment, this invention also relates to a coating composition including a crosslinkable polyester-polyurethane polymer having at least two carbamate sites, a crosslinker, and at least one adjuvant such as a carrier, a lubricant, a pigment, a rheological control agent, a flow control agent, or a combination thereof.
Another embodiment of the present invention includes a coated package comprising a substrate, a cured coating produced from a composition including a crosslinkable polyester-polyurethane polymer that has at least two carbamate sites, a crosslinker, and at least one adjuvant such as a carrier, a lubricant, a pigment, a rheological control agent, a flow control agent, or a combination thereof.
The present invention provides a novel method of coating a packaging container substrate using a crosslinkable coating composition. In addition, the present invention provides a new packaging coating and compositions usable in the food packaging industry.
The coating composition of the present invention preferably comprises a crosslinkable polyester-polyurethane polymer, a crosslinker, and may optionally further comprise at least one adjuvant such as: lubricants, pigments, rheological control agents, flow control agents, and solvents. A catalyst may also be utilized to enhance the cure of the coating composition. The coating composition of the present invention provides one or more features such as: excellent film integrity on applied packages, excellent ability to accept pigmentation, desired chemical stability, enhanced corrosion resistance, and/or required sterilization resistance.
Suitable crosslinkable polyester-polyurethane polymers (xe2x80x9cPE-PU polymerxe2x80x9d) may be formed by reacting a polyester intermediate (xe2x80x9cPE intermediatexe2x80x9d) with a polyisocyanate compound. Preferred PE-PU polymers of the present invention comprise two or more carbamate sites per polymer chain. Such carbamate sites are preferably suitable for crosslinking of the PE-PU polymer by crosslinkers, such as amino resins, phenolic resins, and/or blocked isocyanates.
In one embodiment, the PE intermediate is a hydroxy functional polyester containing hydroxy end groups and the polyisocyanate compound is an organic polyisocyanate. Suitable hydroxy functional polyesters include, for example, the reaction product of (i) a diol of the formula HOROH, where R is an aliphatic, cycloaliphatic, or aromatic hydrocarbon radical that has, preferably between 2 and 40 carbon atoms, more preferably between 2 and 20 carbon atoms, and most preferably between 2 and 12 carbon atoms; and (ii) a dicarboxylic acid of the formula Rxe2x80x2(COOH)2, or an anhydride of such an acid, where Rxe2x80x2 is an aliphatic, cycloaliphatic, or aromatic hydrocarbon radical having preferably 4 to 50 carbon atoms, more preferably 4 to 45 carbon atoms, and most preferably 4 to 40 carbon atoms.
Suitable PE-PU polymers of the present invention have a number average molecular weight (xe2x80x9cMnxe2x80x9d) of at least 5,000, preferably between 5,000 and 35,000, more preferably between 7,000 and 20,000, and most preferably between 9,000 and 15,000. Suitable PE-PU polymers of the present invention have a weight average molecular weight (xe2x80x9cMwxe2x80x9d) of at least 10,000, preferably between 10,000 and 40,000, more preferably between 14,000 and 30,000, and most preferably between 18,000 and 25,000.
Suitable PE-PU polymers of the present invention have a glass transition temperature (xe2x80x9cTgxe2x80x9d) of at least about 0xc2x0 C., preferably at least about 50xc2x0 C., more preferably between about 50xc2x0 C. and 80xc2x0 C., and most preferably between about 60xc2x0 C. and 70xc2x0 C.
Suitable PE-PU polymers of the present invention have a hydroxyl number (OH#) of less than about 5 mg/g, and preferably between 0 and 1 mg/g. The hydroxyl number of a hydroxyl-containing polymer of the present invention is determined by methods as are known in the art such as described in ASTM E-222-00, Test Method C.
The PE-PU polymers in the coating composition of the present invention are preferably present in an amount between about 10 and 100 weight percent, more preferably between about 50 and 100 weight percent, most preferably between about 70 and 95 weight percent of the coating composition.
As previously mentioned, suitable PE-PU polymers may be formed by reacting a polyester intermediate (xe2x80x9cPE intermediatexe2x80x9d) with a polyisocyanate compound.
Suitable PE intermediates for use in the present invention include medium molecular weight, linear, hydroxy functional polyesters. Preferred PE intermediates have a number average molecular weight between about 1,000 and 10,000, more preferably between about 2,000 and 10,000, most preferably between about 4,000 and 8,000. The weight average molecular weight of the PE intermediates is preferably between about 2,000 and 25,000, more preferably between about 5,000 and 25,000, and most preferably between about 10,000 and 20,000. Preferably the hydroxyl number (OH#) of the PE intermediate is between 10 and 100, more preferably between 15 and 85, and most preferably between 20 and 50. Preferred PE intermediates have a glass transition temperature (xe2x80x9cTgxe2x80x9d) of at least about 0xc2x0 C., more preferably at least about 20xc2x0 C., and most preferably between about 40xc2x0 C. and 80xc2x0 C.
The hydroxy functional polyester may be formed by conventional techniques. In one embodiment, a diol and a di-acid are charged into a conventional polymerization vessel and reacted between about 150xc2x0 C. to 240xc2x0 C. for about 12 to 18 hours. Optionally, an esterification catalyst may be used to decrease the reaction time. For example, between about 1 and 1.2 equivalents of a diol may be used with about 1 equivalent of a di-acid, and preferably, between about 1.05 and 1.15 equivalents of diol with 1 equivalent of a di-acid may be used. In general, to ensure the formation of a hydroxy-group terminated polyester, a small excess of diol may be used.
In another embodiment, two moles of a diol are preferably transesterified with one mole of a methyl ester of a di-acid to yield a polyester of desired hydroxyl number.
Typical diols that may be used to form the polyester include, for example, butane diol, butyl ethyl propane diol, 2-methyl 1,3-propane diol, 1,3-propane diol, hexane diol, cyclohexane dimethanol, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, neopentyl glycol, hydroxypivalyl hydroxypivalate, and the like, or mixtures thereof.
Suitable and typical dicarboxylic acids or their corresponding alkyl esters that may be used to form the polyester include adipic acid, azelaic acid, sebacic acid, naphthalene dicarboxylic acid, dodecane dicarboxylic acid, cyclohexane dicarboxylic acid, hexahydrophthalic acid, phthalic acid, terephthalic acid, isophthalic acid, succinic acid, dimer fatty acid, or anhydrides of any of these acids.
Suitable isocyanates for use in the present invention include multi-functional (e.g., di-funtional, tri-functional, etc.) aliphatic, alicyclic or aromatic isocyanates. Preferred isocyanates have at least two (and more preferably exactly two) isocyanate groups in the molecule and are represented by the general formula
Oxe2x95x90Cxe2x95x90Nxe2x80x94Rxe2x80x3xe2x80x94Nxe2x95x90Cxe2x95x90O
wherein Rxe2x80x3 preferably represents a divalent saturated aliphatic hydrocarbon group, saturated alicyclic hydrocarbon group, or aromatic hydrocarbon group, and may include a pendant carboxylic acid group.
Typical diisocyanates that may be used include aliphatic, aromatic or cycloaliphatic diisocyanates such as 1,6-hexamethylene diisocyanate, isophorone diisocyanate, 4,4xe2x80x2-biphenylene diisocyanate, toluene diisocyanate, cyclohexyl diisocyanate, tetramethyl xylylene diisocyanate, ethylethylene diisocyanate, 2,3-dimethylethylene diisocyanate, 1-methyltrimethylene diisocyanate, 1,3-cyclopentylene diisocyanate, 1,4-cyclohexylene diisocyanate, 1,3-phenylene diisocyanate, 1,5-naphthalene diisocyanate, bis-(4-isocyanatocyclohexyl)-methane, 4,4xe2x80x2-diisocyanatiodiphenyl ether, and the like. One presently preferred diisocyanate is isophorone diisocyanate.
Preferred coating compositions of the present invention may also incorporate a crosslinker. The crosslinker usable in the present invention is preferably present in an amount sufficient to cause crosslinking of the reactants within the desired time and temperature. Suitable crosslinkers include multifunctional blocked polyisocyanates; phenolics; amino resins; and the like. Typically useful blocking agents for the blocked polyisocyanates are any of those well known in the art such as alkylketoximes (e.g., methyl ethyl ketoxime), phenols, cyclic lactams, thiols, tertiary alcohols, secondary aromatic amines and dicarbonyl compounds (e.g., diethyl malonate). A presently preferred blocked polyisocyanate usable as the crosslinker is Vestanat B1358, available from Hxc3xcls Degussa.
Suitable and typical amino resins usable as crosslinkers in the present invention include formaldehydes, for example, melamine formaldehyde, urea formaldehyde, glycoluril formaldehyde, and benzoguanamine formaldehyde. A presently preferred amino resin crosslinker is benzoguanamine formaldehyde, available as Cymel 5010 from Cytec Industries of Patterson, N.J.
For coating compositions, the crosslinker is suitably present in the amount up to about 25 weight percent, more preferably about 1 and 20 weight percent, and most preferably between about 5 and 15 weight percent of the total coating composition.
Preferably, the coating composition of the present invention may comprise a catalyst. The catalysts may be used in an amount sufficient to enhance the reaction between the crosslinker and the PE-PU polymer of the present invention. Suitable catalysts include acids, amines, and metal salts. Preferred catalysts include heat-activated catalysts such as phosphoric acid, dibutylin dilaurate, p-toluene sulfonic acid, and dodecylbenzene sulfonic acid (DDBSA). A presently preferred catalyst is DDBSA available as Cycat 600 from Cytec Industries of Patterson, N.J.
Suitable amines and metal salts usable as catalyst in the present invention include tertiary and quaternary amines, and octoates (e.g., zirconium octoate, and zinc octoate). The amount of catalyst present in the present invention is typically less than about 2 weight percent, more typically less than about 1 weight percent, and most typically less than 0.5 weight percent of the total resin solids of the coating composition.
The coating composition of the present invention may optionally include one or more lubricants. Lubricants may be used for one or more of the following effects, including but not limited to: improving ease of handling of the coated substrate; enhancing scuff resistance; or improving fabrication capabilities. Suitable lubricants usable in the present invention include, for example, polyethylene, polytetrafluroethane (PTFE), and natural lubricants such as Carnauba wax, available from Michelman Lubricants of Cincinnati, Ohio. Typical amount of lubricants usable in the present invention depend upon specific application, and preferably up to about 2 weight percent, more preferably between about 0.1 and 1.5 weight percent, and most preferably between about 0.5 and 1.5 weight percent of the coating composition.
The coating composition of the present invention may also include pigments. Pigments are preferably used to give the coating composition the required finish on the packaging. Suitable pigments in this invention are present in the amount sufficient to give the desired opacity, finish texture, and/or general aesthetic quality to the coated substrate. Suitable pigments include aluminum oxides, titanium oxides, zinc oxides, and the like. An example of a pigment usable in the present invention is Ti-Pure R-900 available from E. I. duPont de Nemours of Wilmington, Del. Typical amount of pigments usable in the present invention depends on intended finish and is preferably less than about 30 weight percent of the coating composition.
In an embodiment of the present invention, a rheological or flow control agent may preferably be incorporated into the coating composition. The rheological or flow control agents of the present invention provide the coating composition of the present invention with improved ability to uniformly coat when applied to a substrate. Suitable rheological or flow control agents include acrylics, silicones, waxes, fluoro-surfactants, and the like. A presently preferred rheological and flow control agent usable in the present invention is BYK-Series silicone, available from BYK Chemie of Bad Homburg, Germany. Preferred rheological and flow control agents are usable in the amount of less than 1 weight percent, more preferably less than about 0.5 weight percent of the coating composition.
The coating composition of the present invention may comprise an optional carrier. The optional carrier of the present invention provides a vehicle for facilitating the delivery of the coating composition to the intended substrate. Preferably, the carrier of the present invention is present in the amount sufficient to produce a uniform, blister-free coating. The carrier of the present invention may preferably be removable by heat (and/or vacuum stripping), e.g., during the curing process. Suitable carriers for the coating composition of the present invention include water, and other organic solvents such as alcohols, ketones, esters, aromatic and aliphatic hydrocarbons. Examples of suitable organic solvents include xylene, toluene, methyl ethyl ketone, methyl amyl ketone, methyl isobutyl ketone, dibasic ester, propylene carbonate, N-methyl pyrrolidone and the like. The amount of carrier used in the present invention is preferably between up to about 80 weight percent, more preferably between about 10 and 70 weight percent, and most preferably between about 10 and 50 weight percent of the coating composition.
The benefits of the coating composition of the present invention include one or more of the following: a) ease of application; b) high solids content c) uniform appearance over a variety of substrates; d) chemical stability; e) solvent selection; f) ability to accept pigments; g) ability to allow coated package formation without loss of coating integrity; h) corrosion resistance; i) and sterilization resistance. The coating composition of the present invention provides an environmentally friendly product that is substantially free of vinyl components.
Preferably, the coating composition of the present invention is usable to coat a packaging substrate by a variety of methods. These methods include sheet coating, coil coating, and spray coating. Typically, the packaging substrate is preferably a flat metal substrate prior to coating. The coated flat metal substrate may then be fed through an oven to volatize the solvents and activate any desired crosslinking. The coated substrate may then be formed into a package (or a portion of a package), e.g., by stamping, drawing, machining, or by any other process as is known in the art, and welding the edges if so required.
A method of sheet coating may be by direct roll coating flat sheets of metal, typically about 1 m2. These coated sheets of metal may then be fed through a forced draft, gas-fired oven for about 8 to 15 minutes at peak metal temperatures (PMT) of between about 175 and 230xc2x0 C. Other sheet coating processes are usable and may depend on the equipment and processing capabilities.
A suitable coil coating process preferably includes application by reverse roll-coating onto a continuous metal coil. The continuous metal coil may then be fed through a high-velocity, gas-fired oven for about 9 to 60 seconds at peak metal temperatures (PMT) of between about 215 and 260xc2x0 C.
Spray coating involves the introduction of the coated composition into a preformed packaging container. Typical preformed packaging containers may include food cans, beer and beverage cans, cartons, drug bottles and packages, and the like. The spray coating process preferably utilizes an airless or air-assisted spray nozzle that is capable of uniformly coating the inside of the preformed packaging container. The coated container may then be subjected to heat to remove any residual solvent, cure and/or crosslink the coating. Typically, the coated container is subjected to a gas-fired oven for about 2 to 6 seconds at a peak metal temperature of between about 200 and 235xc2x0 C.
Suitable metal substrates for use in the present invention include: cleaned and pretreated aluminum; tin-free steel (TFS); and electrolytic tin plate (ETP).
For rigid packaging purposes, the coating thickness of the present invention typically ranges between about 2 and 10 microns or between about 0.3 and 1.5 milligrams per square centimeter. Rigid packaging materials usable in the present invention include metals (e.g., aluminum), glass, and plastics.
The coating composition of the present invention may be used to coat the interior or exterior portions of a packaging substrate. The coating of the present invention is preferably flexible enough that a flat coated sheet may be fabricated into a package (or a portion of a package) without cracking, peeling, or otherwise causing the exposure of an uncoated metal substrate. The packaging substrate includes substrates usable for beverage cans, food cans, and the like. These cans comprise different sizes, types and styles. Fabrication of the cans may include folding the coated flat substrate into a cylinder and welding the edges. Ends are then attached to the top and bottom of the folded cylinder. Other fabrication processes include forming a cup or recessed-plate from a flat substrate by stamping, drawing, machining, or by any other process as is known in the art, and welding the edges. An end is then sealed onto the top. A typical food can is usable to package sardines, tuna, and the like. These food cans are sometimes labeled as Draw and Ironed (D and I) or Draw-Redraw (DRD) cans.
Adhesion
Adhesion testing was performed to assess whether the coating adheres to the metal substrate. The adhesion test was performed according to ASTM D 3359xe2x80x94Test Method B, using a Scotch(trademark) 610 tape, available from Minnesota Mining and Manufacturing (3M) Company of Saint Paul, Minn.
Solvent Resistance
The cure of a coating is measured as a resistance to solvents, such as Methyl Ethyl Ketone (MEK), or Acetone. This test was accomplished as described in ASTM D 5402-93. The number of double rubs (i.e., one back-and-forth motion) is recorded.
Blush Resistance
Blush resistance measures the ability of a coating to resist attack by various solutions. Typically, it is measured by the amount of water absorbed into a coating. When the coated substrate absorbs water, it is generally cloudy or looks white.
Sterilization or Pasteurization
The sterilization or pasteurization test determines how a coating withstands the processing conditions for different types of food packaged in the container. Typically, a coated substrate is immersed in a water bath and heated to between 65 and 100xc2x0 C. for about 15 to 60 minutes. The coated substrate is then removed from the water bath and tested for coating adhesion and blush.
Process or Retort Resistance
This is measure of the decomposition of the coated substrate using heat and pressure. The procedure is similar to Sterilization or Pasteurization test (above) except that the testing is accomplished by subjecting the container to heat of between about 105 and 130xc2x0 C.; pressure of between about 0.7 to 1.0 kg/cm2; and for about 15 to 90 minutes. The coating is then tested for adhesion and blush.
Corrosion Resistance
This test is a measure of the ability of the container to resist corrosion when exposed to food or beverage. This test is similar to the Process or Retort Resistance test above, except that it uses food, beverage or food/beverage simulators instead of water. These simulators may include 3% acetic acid, 1% lactic acid, 1% citric acid, and the like. The coated substrate is then evaluated for adhesion and blush.
Fabrication
This test measures the ability of the coated container to retain its integrity as it undergoes the formation process necessary to produce a coated container. It is a measure of the presence or absence of cracks or fractures in the coated container. A coated container is typically filled with electrolyte solution are tested for amount of electrical current that can pass through the container. If the coating remains intact (no cracks or fractures) after fabrication, no current will pass through the container.

Method of coating a packaging container using crosslinkable polyester-polyurethane


An injection molding system for a metal alloy includes a feeder in which the metal alloy is melted and a barrel in which the liquid metal alloy is converted into a thixotropic state. An accumulation chamber draws in the metal alloy in the thixotropic state through a valve disposed in an opening between the barrel and the accumulation chamber. The valve selectively opens and closes the opening in response to a pressure differential between the accumulation chamber and the barrel. After the metal alloy in the thixotropic state is drawn in, it is injected through an exit port provided on the accumulation chamber. The exit port has a variable heating device disposed around it. This heating device cycles the temperature near the exit port between an upper limit and a lower limit. The temperature is cycled to an upper limit when the metal alloy in the thixotropic state is injected and to a lower limit when the metal alloy in the thixotropic state is drawn into the accumulation chamber from the barrel.

1. Field of the Invention
The invention relates to a method and apparatus for manufacturing metal alloys, more particularly to a method and apparatus for manufacturing a light metal alloy by the process of injection molding the metal alloy when it is in a thixotropic (semi-solid) state.
2. Description of the Related Art
One conventional method used to produce molds of metal alloys is the die cast method. The die cast method is disclosed in U.S. Pat. Nos. 3,902,544 and 3,936,298, both of which are incorporated by reference herein. The die cast method uses liquid metal alloys during casting and as a consequence, metal alloys produced from this method have low densities. Metal alloys having low densities are not desirable because of their lower mechanical strength, higher porosity, and larger micro shrinkage. It is thus difficult to accurately dimension molded metal alloys, and once dimensioned, to maintain their shapes. Moreover, metal alloys produced from die casting have difficulty in reducing the resilient stresses developed therein.
The thixotropic method improves upon the die casting method by injection molding a metal alloy from its thixotropic (semi-solid) state rather than die casting it from its liquid state. The result is a metal alloy which has a higher density than one produced from the die casting method.
A method and apparatus for manufacturing a metal alloy from its thixotropic state is disclosed in U.S. Pat. No. 5,040,589, which is incorporated by reference herein. A method of converting a metal alloy into a thixotropic state by controlled heating is disclosed in U.S. Pat. Nos. 4,694,881 and 4,694,882, both of which are incorporated by reference herein.
The system disclosed in U.S. Pat. No. 5,040,589 is an in-line system, in which the conversion of the metal alloy into a thixotropic state and the pressurizing of the same for the purposes of injection molding is carried out within a single cylindrical housing. With such a system, it is difficult to control the molding conditions, i.e., temperature, pressure, time, etc., and as a result, metal alloys of inconsistent characteristics are produced.
Moreover, the system of U.S. Pat. No. 5,040,589 requires that the metal alloy supplied to the feeder be in pellet form. As a consequence, if a mold of undesired characteristics are produced by its system, recycling of the defective molds is not possible unless the defective molds are recast in pellet form.
An improved system for manufacturing light alloy metals, which is capable of accurately producing molded metal alloys of specified dimensions within a narrow density tolerance, is desired. Further, a production process for light alloy metals which can consistently produce molded metal alloys of desired characteristics, and which can easily accommodate recycling of defective molds would represent a substantial advance in this art.
An object of the invention is to provide a method and apparatus for producing metal alloys through injection molding.
Another object of the invention is to provide an improved injection molding system for metal alloys which is capable of producing molded metal alloys of accurate dimensions within a narrow density tolerance.
Still another object of the invention is to provide an injection molding system for light alloy metals which is capable of producing light alloy metals of desired characteristics in a consistent manner.
Still another object of the invention is to provide an injection molding system for light alloy metals which accommodates recycling of defective molds easily.
These and other objects are accomplished by an improved injection molding system for metal alloys in which the steps of melting the metal alloy, converting the metal alloy into a thixotropic state, and injecting the metal alloy in the thixotropic state into a mold are carried out at physically separate locations.
The improved system comprises a feeder in which the metal alloy is melted and a barrel in which the liquid metal alloy is converted into a thixotropic state. An accumulation chamber draws in the metal alloy in the thixotropic state through a valve disposed in an opening between the barrel and the accumulation chamber. The valve selectively opens and closes the opening in response to a pressure differential between the accumulation chamber and the barrel.
After the metal alloy in the thixotropic state is drawn in, it is injected through an exit port provided on the accumulation chamber. The exit port has a variable heating device disposed around it. This heating device cycles the temperature near the exit port between an upper limit and a lower limit. The temperature is cycled to an upper limit when the metal alloy in the thixotropic state is injected and to a lower limit when the metal alloy in the thixotropic state is drawn into the accumulation chamber from the barrel.
A piston-cylinder assembly supplies the accumulation chamber with the pressure necessary to inject the metal alloy in the thixotropic state and with the suction necessary to draw in the metal alloy in the thixotropic state from the barrel.
Additional objects and advantages of the invention will be set forth in the description which follows. The objects and advantages of the invention may be realized and obtained by means of instrumentalities and combinations particularly pointed out in the appended claims.

Method and apparatus for manufacturing light metal alloy


An embodiment of a method for reducing chroma noise in digital image data and of a corresponding image processor. Chrominance components are subjected to low-pass filtering. The strength of the low-pass filtering is modulated in accordance with the dynamic range of the luminance signal and the dynamic range of each of the two chrominance signals in order to avoid color bleeding at image-object edges. Moreover, the low-pass filtering is selectively applied to pixels with similar luminance and chrominance values only. A combination of down-sampling and up-sampling units is employed so that comparatively small filter kernels may be used for removing chroma noise with low spatial frequency.

There are different sources of noise in digital images acquired by image sensors in digital cameras, camcorders, and scanners, including fixed-pattern noise and temporal noise. Many factors determine the overall noise characteristics in an image: sensor type, pixel dimensions, temperature, exposure time, etc. Noise can also vary within an individual image. For digital cameras, darker regions may contain more noise than the brighter regions. Moreover, noise is space varying and channel dependent. The blue channel is usually the noisiest channel. Classical noise-reduction techniques remove noise from the Bayer image, before the color interpolation step. Thus, they often assume the noise to be uncorrelated for different pixels. The amount of noise which is not removed by the noise reduction technique is often spread in a neighborhood by the color-interpolation algorithm, which infers missing color components. Consequently, noise may have low-frequency (coarse-grain) and high-frequency (fine-grain) variations. High-frequency noise is relatively easier to remove than low-frequency noise, which may be difficult to distinguish from the real image signal. Moreover, noise is composed of two elements: fluctuations in color and luminance. Color or "chroma" noise is usually more unnatural in appearance than luminance noise, and can render images unusable if not kept under control. This kind of noise may appear as low-frequency, colored blobs in regions of low spatial frequency. These colored blobs may be irregularly shaped and are typically around 5 to 25, or more, pixels wide in a given direction, and usually are more pronounced in darker regions than in brighter regions.
A conventional approach to chroma-noise reduction is disclosed in U.S. Pat. No. 6,980,326, which is incorporated by reference. This approach includes using standard gray-scale image-noise-reduction techniques on each color channel separately, thus ignoring any interactions or correlations between the color channels. This technique can produce an excessive desaturation of genuine chrominance details. Early state-of-the-art techniques for removing chroma-noise artifacts usually convert the image into a luminance-chrominance space (YCrCb or CIELAB), apply some simple, but effective, methods such as mean, smoothing, or median filtering to the chrominance channels, and then convert the image back to the original color space. A shortcoming of this approach is that there is no discrimination between false colors and genuine chrominance details. Consequently, sharp, colored edges in the image begin to bleed color as the blurring becomes more aggressive. The problem of color bleeding can be contained using a small, fixed-blur kernel. But to remove low-frequency chroma blobs, large blur kernels are typically required.
U.S. Pat. No. 7,084,906, which is incorporated by reference, addresses the problem of removing color moiré artifacts from images by blurring chrominances in low-frequency activity neighborhoods, excluding edges. Down-sampled luminance and chrominance signals are used to separate the image into textured and non-textured regions. In particular, a binary texture map, which identifies low-frequency activity (LFA) areas, is constructed by threshold, erosion, and dilation operations. The average of the chrominances belonging to the LFA area within a 7×7 spider-shaped region is computed, thus removing color moiré artifacts. Also, to clean the non-textured regions of the image, a simple sigma filtering of the chroma channels is performed in a 3×3 support region (9×9 at the original pixel resolution). In particular, the absolute difference in chrominance between each neighboring pixel and the central pixel is computed. If both chroma channel values are within a threshold (usually set to 10 for 8-bit images), then the pixel is included in the cleaning calculations. This means that chroma noise is reduced by averaging pixels which have very similar chrominance values to the central one, thus avoiding color bleeding.
EP Patent 1093087 A2, which is incorporated by reference, provides a solution for reducing chroma noise with the use of large blur kernels without causing color bleeding at sharp, colored edges. More specifically, the disclosed technique firstly identify all the edges and boundaries in the image, and then allows a calculation-neighborhood region to adaptively grow until it encounters an edge. To create the edge map, four edge-detector filters are convolved with each channel (Lab), and the results are added together. Then the algorithm moves out in each of the eight compass directions, one pixel at a time, examining the edge-map values. If the difference between an edge-map value and the central-pixel value is less than a threshold, then that pixel is added to the smoothing neighborhood; otherwise, the growth of the smoothing region in that direction is stopped. A maximum radius value might be in the range of about 50 to 100 pixels. Within the smoothing region, the a and b channels are averaged. Eventually, the image is converted back to the original color space.
In the article "Multiresolution bilateral filtering for image denoising" by M. Zhang and B. K. Gunturk (IEEE Transactions on Image Processing, vol. 17, no. 12, December 2008), which is incorporated by reference, a multi-resolution technique is proposed to remove noise from images, because it is possible to distinguish between noise and image information better at one resolution level than another. Coarse-grain noise becomes fine-grain as the image is decomposed further into its subbands, and, hence, it could be eliminated at a lower level. The proposed framework decomposes the noisy signal into its frequency subbands with wavelet decomposition; as the signal is reconstructed back, bilateral filtering is applied to the approximation subbands. In addition, it is possible to apply wavelet thresholding to the detail subbands. As the number of decomposition levels increases, chroma noise is better removed, but bleeding effects increase as well.


A semiconductor memory device having a NAND-type memory cell structure for preventing the occurrence of an electrical bridge resulting from impurity particles generated during a manufacturing process. The space between the word-line whereto a Vcc voltage is applied and the string selection line whereto a Vss voltage is applied and a space between the string selection line of the string selection transistor and the word-line of the cell transistor adjacent to the string selection transistor, are wider than that between the word-lines so as to prevent early stand-by current failure caused by the special stand-by conditions of a NAND-type memory cell. Therefore, the occurrence of a polysilicon bridge between the word-line and the string selection line due to impurity particles generated during the manufacturing process is prevented. As a result, a defectively manufactured chip can be resurrected by the data correction means provided within the memory device.

The present invention relates to a semiconductor memory device, and more particularly, to a semiconductor device having a NAND-type memory structure.
A NAND-type memory cell structure is in use for almost all memory cells of the 4M bit level and higher, due to its advantage of easy high integration.
FIGS. 1 and 2 show the layout and equivalent circuit of the conventional NAND-type mask read-only-memory (ROM) cell structure.
Referring to FIG. 1, reference numeral 1 indicates an N.sup.+ active region used as the drain and source of a transistor, reference numeral 2 is an ion doped region having a depletion-type channel, reference numeral 3 is a region used as the gate electrode of the transistor and as connecting means inside the chip, reference numeral 4 is a contact hole region for interconnecting between the active region and a metal wiring, and between the metal wiring and a polysilicon layer, and reference numeral 5 is a metal wiring (bit-line) used as the connecting means.
As shown in FIGS. 1 and 2, in the conventional NAND-type mask ROM cell, two strings in parallel one of which is constituted by two string selection transistors and multi-cells numbering 4, 8, 16, 32 and so on which are serially connected between the bit-line contact and the ground line by equal spaces, are connected to one bit-line contact, to thereby constitute a basic unit in constructing the memory cell array. Here, one string comprises two transistors having an enhancement-type channel and depletion-type channel, respectively.
The conventional NAND-type mask ROM cell operates as follows, with reference to FIGS. 1, 2 and 3. Operation when cell A is turned on while cell B is turned off in FIGS. 1 and 2 will be explained.
First, in stand-by operation, the string selection line is at zero volts (0 V), the word-line is at Vcc level, and the bit line is floated. In read mode operation, when the string selection line 1 is Vcc level and the string selection line 2 is at 0 V, the string 1 is selected. In string 1, word-line 2 is switched to 0 V and the remaining word-lines thereof are switched to Vcc level, in order to select the cell transistor A of FIG. 2. At this time, the voltage of a bit line is determined as the selected cell, that is, a logic "low" or "high" depending on the state of cell A, is determined. In other words, logic "high" is selected when cell A is an enhancement-type NMOS, and logic "low" is selected when cell A is a depletion-type NMOS. A sense amplifier detects the bit-line voltage, thereby determining the data input/output (I/O).
FIGS. 4, 5 and 6 respectively show the layout, equivalent circuit thereof and the operation state of the memory cell structure where the ground selection line is added to the conventional NAND-type mask ROM cell so as to open the current path between word-line Vcc and ground in stand-by mode when a gate oxide film of cell transistor fails, i.e., when the oxide film is damaged.
Referring to the operations of the memory cell, the ground selection line is switched to "0 V" in stand-by mode, while the remaining operations are the same as those of the conventional NAND-type memory cell.
The occurrence of a polysilicon bridge resulting from impurity particles increases geometrically as the layout of the conventional NAND-type memory cell increases to ultra-high integration. Accordingly, the error correction code (ECC) or redundancy is provided so as to improve yield and reliability. However, a chip becomes defective due to poor stand-by current which has to be tested in the early stages of manufacturing when the string selection line and word-line or the word-line and ground selection line are electrically connected by the polysilicon bridge. Accordingly, the data correction effect by the ECC circuit or by a redundancy circuit cannot be obtained.

Semiconductor memory NAND with wide space between selection lines


A modular power supply architecture for automatic test equipment is disclosed. The power supply architecture includes a control module having a control signal output line and a plurality of output modules. The control module includes control circuitry to generate a control signal along the control signal output line and measurement circuitry coupled to the control signal output line. The output modules have respective control inputs coupled in parallel to the control signal output line to receive the control signal and respective current outputs connected in parallel. The output modules are operative in response to the control signal to generate respective currents at the current outputs. A current output bus receives and sums the respective current outputs, the output bus being isolated from the control signal line.

The invention relates generally to automatic test equipment and more particularly a device-under-test (DUT) power supply for use with a semiconductor tester.
Automatic test equipment (ATE) provides the ability for semiconductor device manufacturers to test each and every device fabricated. This enables the manufacturer to prevent defective devices from entering the marketplace, thereby maximizing quality and reliability. Not surprisingly, this correspondingly translates to higher product revenues. With the complexity and sophistication of todays modern semiconductor devices, ATE in a semiconductor manufacturing plant is a necessity in order for the manufacturer to remain competitive.
Conventional ATE typically provides power supplies to supply power to a device-under-test (DUT). Given that a semiconductor tester may be used to test a wide range of devices, the current required may vary over a wide range. Further, there may be cases where a tester user may want to test several devices in parallel. This combination of requirements is frequently addressed by designing a number of power supplies, each having the ability to generate some small current. These supplies are often designed so they can be paralleled to produce a smaller number of higher power supplies.
Paralleling a large number of power supplies often encounters several problems, including unequal current sharing, inaccuracies in summed current measurements and current clamping, and undesirable circuit complexities at the power supply output. Because accuracy requirements for DUT power supplies are generally couched in terms of output voltage and current, minimizing any adverse effects at the output is highly desirable.
What is needed and heretofore unavailable is a high-accuracy device power supply for ATE applications capable of addressing the paralleling problems noted above. The modular ATE power supply architecture of the present invention satisfies this need.
The modular ATE power supply architecture of the present invention provides a modular way to scale the output of a DUT power supply with minimal circuit complexity in the output stages. This allows for straightforward parallel configurations that are easily controllable and highly accurate.
To realize the foregoing advantages, the invention in one form comprises a modular power supply architecture for automatic test equipment. The power supply architecture includes a control module having a pair of control signal output lines and a plurality of output modules. The control module includes control circuitry to generate control signals along the control signal output lines and measurement circuitry coupled to the control signal output lines. The output modules have respective control inputs coupled in parallel to the control signal output line to receive the control signals and respective current outputs connected in parallel. The output modules are operative in response to the control signals to generate respective currents at the current outputs. A current output bus receives and sums the respective current outputs, the output bus being isolated from the control signal line.
In another form, the invention comprises a method of supplying power to a device-under-test. The method includes the steps of selecting a control module comprising control circuitry for generating respective sink and source control signals along respective source and sink control lines; paralleling a plurality of output current modules to receive the sink and source control signals from the respective source and sink control lines; summing the output currents from the output current modules to an output current bus; and isolating the output current bus from the control circuitry. Any control section can drive any number of output sections, said output sections may or may not be of equal current capability. The total output current capability of the power supply created by the combination of elements is just the total of the paralleled output sections, and the total transconductance is the sum of transconductances of those output sections.
Other features and advantages of the present invention will be apparent from the following detailed description when read in conjunction with the accompanying drawings.


A precharge circuit is provided with an N-channel transistor intended for switching. A reference potential is applied to either one of the source and drain of this N-channel transistor. The other of the source and drain is connected to a node. A precharge signal is applied to the gate of the N-channel transistor. The reference potential is set to a precharge output potential for the case of displaying black on a pixel, i.e., the potential when a minimum current flows through a P-channel transistor connected to the other of the source and drain of the N-channel transistor.

1. Field of the Invention
The present invention relates to a driving circuit of a current-driven device for driving a current-driven device which is driven by supply of an electric current, a current-driven apparatus having this driving circuit and a current-driven device, and a method of driving this current-driven apparatus.
The present invention is applicable to an organic EL display, as well as such current-driven displays as an inorganic EL display and an LED, such current-driven memories as an MRAM, and driving circuits thereof.
2. Description of the Related Art
Current-driven apparatuses which are controlled in operation by electric currents supplied thereto have been developed heretofore. Among such current-driven apparatuses is an organic electro luminescence (EL) display.
With the advance of development, organic EL devices to be used in organic EL displays have improved in efficiency, contributing to reduced power consumption of the organic EL displays. The improved efficiency of the organic EL devices, however, makes the currents to be passed through the organic EL devices smaller, which requires a driving circuit for supplying (writing) the organic EL devices with these small currents accurately at speed. The inventors have formerly invented such a driving circuit, and disclosed it in Japanese Patent Laid-Open Publication No. 2003-195812.
FIG. 1 is a block diagram showing a conventional EL display described in Japanese Patent Laid-Open Publication No. 2003-195812. FIG. 2 is a circuit diagram showing a current source and a precharge circuit for each single data line, and a pixel circuit for each single pixel in the organic EL display shown in FIG. 1.
As shown in FIG. 1, the organic EL display 500 has a display unit 400. The display unit 400 is provided with a plurality (Y) of control lines 110 which extend in the horizontal direction, and a plurality (X) of data lines 120 which extend in the vertical direction. Pixels 100 are arranged at respective intersections of the control lines 110 and the data lines 120. Consequently, the display unit 400 has (X×Y) pixels 100 which are arranged in a matrix. Incidentally, when the organic EL display 500 is a color display, three adjoining pixels 100 arranged in the horizontal direction constitute a single group in which the pixels 100 emit light in red (R), blue (B), and green (G), respectively. The pixels 100 each have an organic EL device as its light-emitting device.
In addition, the organic EL display 500 has a vertical scanning circuit 300 which lies along a vertical side of the display unit 400 and is connected with the control lines 110. The vertical scanning circuit 300 selects the control lines 110 in succession. The organic EL display 500 also has a horizontal driving circuit 200 which lies along a horizontal side of the display unit 400 and is connected with the data lines 120. The horizontal driving circuit 200 supplies current signals to the pixels 100 that are connected to a control line 110 selected by the vertical scanning circuit 300. The light-emitting devices arranged in the pixels 100 have a proportional relationship between the currents supplied thereto and the luminances thereof. The currents supplied to the pixels 100 through the data lines 120 are adjusted in intensity so that the pixels 100 achieve display with tone levels. Note that the horizontal driving circuit 200 and the vertical scanning circuit 300 constitutes the driving circuit of the organic EL display 500.
As shown in FIG. 2, the horizontal driving circuit 200 is provided with a plurality (X) of current sources 220 for outputting current signals Iout to the respective data lines 120 of the display unit 400 (see FIG. 1). Precharge circuits 250 for precharging the data lines 120 are connected between the current sources 220 and the data lines 120.
Each pixel 100 has a pixel circuit in which a P-channel transistor T21 intended for current storage, a P-channel transistor T24 intended for switching, and a light-emitting device or organic EL device 130 are connected in series in this order between a supply voltage Ve1 and a ground potential GND. The gate of the current storing P-channel transistor T21 is connected to a data line 120 through N-channel transistors T22 and T23 intended for switching. The gates of the switching transistors T22 to T24 are connected to a control line 110. Besides, a capacitor C1 is arranged between the gate of the current storing transistor T21 and the supply voltage Ve1. The node between the switching transistors T22 and T23 is connected to the node between the current storing transistor T21 and the switching transistor T24, whereby the gate of the current storing P-channel transistor T21 is connected to the drain of the transistor T21 through the switching transistor T22. A parasitic capacitance Cp1 lies between the data line 120 and the ground potential.
Each precharge circuit 250 undergoes the supply voltage Ve1. For a potential generating circuit, a P-channel transistor T35 intended for driving and an N-channel transistor T31 intended for switching are connected in series in this order between the terminal to which the supply voltage Ve1 is applied and the current source 220. More specifically, either one of the source and drain (hereinafter, referred to as one terminal) of the N-channel transistor T31 is connected to the driving P-channel transistor T35. The other of the source and drain (hereinafter, referred to as the other terminal) is connected to the ground potential through the current source 220. Incidentally, the driving P-channel transistor T35 has the same size as that of the current storing P-channel transistor T21 of the pixel 100. The two transistors thus have substantially the same characteristics. The precharge circuit 250 also has N-channel transistors T32 and T33 and a P-channel transistor T34 which are intended for switching. The gates of these switching transistors T31 to T34 are connected to wiring 252. A precharge signal PC2 is input to the wiring 252 from exterior.
Then, the node A between the driving P-channel transistor T35 and the switching N-channel transistor T31 is connected to one terminal of the N-channel transistor T33 intended for switching. The other terminal of this transistor T33 is connected to the gate of the driving P-channel transistor T35. A voltage follower amplifier 251 is arranged between the node A and the switching transistor T32. The node A is connected to the noninverting input terminal of this voltage follower amplifier 251. The output of the amplifier 251 is connected to one terminal of the transistor T32 and the inverting input terminal of the amplifier 251. The other terminal of the transistor T32 is connected to the data line 120. Moreover, one terminal of the switching P-channel transistor T34 is connected to the current source 220. The other terminal of the transistor T34 is connected to the data line 120.
Next, description will be given of the operation of the organic EL display which is configured as described above. Initially, the vertical scanning circuit 300 shown in FIG. 1 scans the control lines 110. More specifically, the vertical scanning circuit 300 selects the first control line 110 to the Yth control line 110 in succession, applying a signal of high level to the selected control line 110.
Then, the current sources 220 in the horizontal driving circuit 200 output the current signals to the respective data lines 120. At this time, the horizontal driving circuit 200 passes currents corresponding to the tone levels to be displayed on the pixels 100 that are connected to the control line 110 selected by the vertical scanning circuit 300, through the data lines 120 in connection with the pixels 100. Consequently, as shown in FIG. 2, the current signal Iout is supplied to the switching N-channel transistor T31 and the switching P-channel transistor T34 in each precharge circuit 250. If the precharge signal PC2 is not selected, i.e., at low level, the switching N-channel transistors T31 and T32 turn off and the switching P-channel transistor T34 turns on. The current signal Iout is thus supplied from the current source 220 to the data line 120 through the transistor T34. In this way, the horizontal driving circuit 200 outputs the current signals Iout to the data lines 120.
In each of the pixels 100 that are selected by the vertical scanning circuit 300 (see FIG. 1), the signal of high level, indicating selection, is applied to the control line 110. This turns on the switching N-channel transistors T22 and T23. As a result, the data line 120 is connected to the gate of the current storing P-channel transistor T21 and one end of the capacitor C1 through the transistors T23 and T22. Moreover, the switching P-channel transistor T24 is turned off. This determines the amount of the current to flow through the current storing P-channel transistor T21, and charges the capacitor C1. The pixel 100 is thus written with the current signal Iout.
Then, the vertical scanning circuit 300 scans the next control line, and the potential of the control line 110 shown in FIG. 2 is switched from high level (selected) to low level (not selected). Then, the switching N-channel transistors T22 and T23 turn off, and the switching P-channel transistor T24 turns on. As a result, the current path consisting of a series connection of the current storing P-channel transistor T21, the switching P-channel transistor T24, and the organic EL device 130 in this order is formed from the supply voltage Ve1 to the ground potential GND independent of the data line 120. More specifically, the supply voltage Ve1 is applied to one terminal of the current storing P-channel transistor T21. The other terminal of this transistor T21 is connected to one terminal of the switching P-channel transistor T24. The other terminal of this transistor T24 is connected to the input terminal of the organic EL device 130. The output terminal of this organic EL device 130 is subjected to the ground potential GND. As a result, the current written in the current storing P-channel transistor T21 flows through this current path, and the organic EL device 130 emits light at a tone level corresponding to this current. In this case, the capacitor C1 maintains the gate potential of the current storing P-channel transistor T21 at a constant value. The amount of the current flowing through the transistor T21 is thus maintained at a constant value, so that the luminance of the organic EL device 130 is maintained at a predetermined tone level.
The vertical scanning circuit 300 thus scans the control lines 110 to select the Y control lines 110 one by one in succession. Upon each selection, the horizontal driving circuit 200 outputs the current signals Iout corresponding to intended tone levels to the pixels 100 that are in connection with the control line 110 selected by the vertical scanning circuit 300. An image is displayed on the display unit 400 in this way.
As above, the display unit 400 can theoretically display images without the precharge circuits 250. Nevertheless, since the data lines 120 are accompanied with the parasitic capacitances Cp1, the parasitic capacitances Cp1 must be charged and discharged each time the potentials of the data lines 120 are changed. Setting the data lines 120 to a desired value of potential thus requires a certain amount of write time. Besides, the smaller the current signals Iout to be supplied to the data lines 120 are, the longer the write time becomes. Meanwhile, in order to display flicker-free images to viewers, the vertical scanning circuit 300 must scan the control lines 110 at or above a certain speed. This means an upper limit to the duration for each single control line 110 to be selected for. On this account, excessive write time can result in insufficient write operations, with the problem of degraded image quality.
Then, in the conventional example described in Japanese Unexamined Patent Application Publication No. 2003-195812, the precharge circuits 250 are provided between the current sources 220 and the data lines 120. As shown in FIG. 2, in each of the precharge circuits 250, the precharge signal PC2 is switched to high level (selected) immediately after a new control line 110 is selected. Consequently, the switching N-channel transistors T31 to T33 turn on, and the switching P-channel transistor T34 turns off. As a result, the current signal Iout output from the current source 220 is supplied to the driving P-channel transistor T35 through the transistors T31 and T33. This determines the amount of the current to flow through the driving P-channel transistor T35, and sets the potential of the node A to a potential corresponding to the current signal Iout. Incidentally, the transistor T35 has substantially the same size and characteristics as those of the transistor T21 in each pixel 100. The potential of the node A mentioned above thus becomes substantially the same as that of the gate of the transistor T21 when the current signal Iout is applied to the transistor T21. Then, the potential of the node A is applied to the noninverting input terminal of the voltage follower amplifier 251, and the same potential as that of the node A is output from the output terminal of the voltage follower amplifier 251 to the data line 120. The voltage follower amplifier 251 has a high capability for current supply, and can thus charge and discharge the parasitic capacitance Cp1 of the data line 120 quickly. That is, because of the provision of the precharge circuit 250, the potential of the data line 120 can be set to a potential corresponding to the current signal Iout more quickly than when no precharge circuit 250 is provided.
Subsequently, the precharge signal PC2 is switched to low level (unselected), and the current signal Iout is supplied directly to the data line 120. At this time, the data line 120 is already given a potential close to the target value by the foregoing operation of the precharge circuit 250, and the current signal Iout has only to correct a precharge-time error in the potential of the data line 120. This correction requires not much time. As a result, it is possible to reduce the write time of the pixel 100. Incidentally, the precharge-time error in the potential of the data line 120 occurs due to an input offset voltage of the voltage follower amplifier 251 and characteristic differences between the driving P-channel transistor T35 and the driving P-channel transistor T21.
The foregoing conventional technique, however, has the following problems. As shown in FIG. 2, in each precharge circuit 250, parasitic capacitances arise between the wiring for the current signal Iout to flow through and the ground potential. More specifically, the wiring from the transistor T35 to the noninverting input terminal of the voltage follower amplifier 251 is accompanied with a parasitic capacitance Cp2. The wiring from the current source 220 to the transistors T31 and T34 is accompanied with a parasitic capacitance Cp3. Incidentally, the parasitic capacitance Cp2 consists chiefly of the gate capacitor of the driving P-channel transistor T35 when the switching N-channel transistor T33 is on, and the input capacitor of the voltage follower amplifier 251. The parasitic capacitance Cp3 consists chiefly of capacitors occurring between the laid wiring and other wiring. These parasitic capacitances Cp2 and Cp3 are smaller than the parasitic capacitance Cp1 of the data line 120. Nevertheless, these parasitic capacitances Cp2 and Cp3 increase the settling time to elapse between when the precharge signal PC2 is selected, or switched to high level, and when the precharge output potential, or the potential applied to the noninverting input terminal of the voltage follower amplifier 251, converges to a certain value. The reason for this is that the parasitic capacitances Cp2 and Cp3 must be charged and discharged each time the value of the current signal Iout is changed.
FIG. 3 is a chart for showing the effect of the current signal Iout on the settling time of the input potential of the voltage follower amplifier. In the chart, the abscissa indicates the intensity of the current signal Iout, and the ordinate the settling time of the input potential of the voltage follower amplifier. Incidentally, "ΔV" shown in FIG. 3 represents a variation in the input potential of the voltage follower amplifier. The potential variation ΔV shows a difference between the potential of the data line 120 when a control line 110 is selected and the potential of the data line 120 when the next control line 110 is selected.
As shown in FIG. 3, the lower the intensity of the current signal Iout is, the longer the settling time of the input potential of the voltage follower amplifier becomes. In a pixel that emits light of a lower tone level, i.e., darker tone level, the smaller current signal Iout can make the settling time extremely longer. With a level-zero display, or black display, the settling time reaches its maximum. In addition, with recent improvements to the efficiency of the organic EL device, the current signal Iout decreases accordingly. The settling time of the input potential of the voltage follower amplifier is thus becoming increasingly long. Moreover, the greater the potential variation ΔV is, the longer the settling time of the input potential of the voltage follower amplifier becomes. This is equivalent to the case, for example, where the current signal Iout has a higher intensity when a control line 110 is selected, and the current signal Iout has a lower intensity when the next control line 110 is selected.
The longer settling time of the input potential of the voltage follower amplifier then increases the time necessary for precharge. This accordingly decreases the time for outputting the current signal Iout directly to the pixel 100, thereby hindering sufficient correction on precharge-time errors in the potentials of the data line 120. Consequently, the accuracy in writing the current signal Iout to the pixel 100 lowers with a drop in image quality. Specifically, trailing defects can occur from writing failures, for example.

Driving circuit of current-driven device, current-driven apparatus, and method of driving the same

NEC Corporation and NEC Electronics Corporation