The ion-implanting apparatus includes an implanting control device 26a having the functions of sweeping an ion beam by a sweeping magnet 12 and scanning a target by a scan mechanism. The implanting control device 26a has the functions of changing a sweep frequency of the ion beam to be swept by said sweeping magnet according to at least one of the species and energy of the ion beam and changing the minimum number of times of scanning of the target to be scanned by said scan mechanism according to the changing of the sweep frequency.

1. Field of the Invention
This invention relates to a hybrid scanning type of ion-implanting apparatus and ion-implanting method which magnetically sweep an ion beam and mechanically scan a target, and more particularly to means capable of sweeping an ion beam in a wide variety of energies and ion species and shortening an ion-implanting time to improve the throughput of the device. In this specification, the magnetic reciprocative scanning of the ion beam is referred to as xe2x80x9csweep or sweepingxe2x80x9d, and the mechanical reciprocative scanning of the target is referred to xe2x80x9cscan or scanningxe2x80x9d.
2. Description of the Related Art
Ion implantation, it is important to implant ions into a target (e.g. wafer) with good uniformity. This is particularly important when the ion implantation is adopted in a semiconductor manufacturing process. As the case may be, it is desired to irradiate the target with the ion beam scanned in parallel.
A conventional art of the ion-implanting apparatus proposed to fulfill the above-mentioned demand is shown in FIG. 2. This apparatus basically has the same structure as described in Japanese Patent Unexamined Publication No. Hei. 8-115701(JP-A-8-115701).
The ion-implanting apparatus includes an ion source 2 for drawing an ion beam 4, a mass separation magnet 6 for selecting a specific ion species drawn therefrom, an accelerator tube 8 for accelerating or decelerating the ion beam derived therefrom, a mass separation magnet 10 (also referred to as xe2x80x9cenergy separation magnetxe2x80x9d) for selecting the ion species with a specific energy from the ion beams 4 derived therefrom, a sweeping magnet 12 for sweeping the ion beam derived therefrom in an X-direction(for example, horizontal direction) under a magnetic field, and paralleling magnet 14 for bending the ion beam 4 derived therefrom again to scan the ion beam 4 in parallel in cooperation with the sweeping magnet, i.e. making the ion beam 4 in parallel to a Z-axis which is a movement direction of the ion beam 4. The ion species is defined by the mass number and the valence of the ion.
The ion beam 4 derived from the paralleling magnet 14 is applied to a target (e.g. wafer) 20 held in a holder 8 of a scan mechanism 16. Referring to FIG. 3, the scan mechanism 16 mechanically scans the target 20 within a sweep region 4a of the ion beam 4 in a Y-direction (e.g. vertical direction) perpendicular to the above X direction. Due to a cooperation between the scanning of the target 20 and the sweep of the ion beam 4, the ion can be implanted into the entire surface of the target 20 with good uniformity.
The ion-implantation in this ion-implanting apparatus can be controlled by a control circuit including an implanting control device 26 as shown in FIG. 4.
The desired ion species, beam energy, beam current (beam quantity) and implanting quantity are set by a man-machine interface 28 and supplied to an implanting control device 26.
The implanting control device 26 calculates the number of times of scanning of the target 20 for realizing the aimed implanting quantity by the aimed beam current on the basis of these items of set information, and controls the scan mechanism 16 through a scan control unit 32 to realize it. The scan mechanism 16 converts a control signal supplied from the scan control device 26 into a signal for driving a motor in the scan mechanism 16.
The initial value of the scan speed of the target 20 is constant, and made variable during implantation by the implanting control device 26 according to a change in the beam current of the ion beam 4 which is implanted. Specifically, as the beam current decreases, the scan speed is decreased. Inversely, as the beam current increases, the scan speed is increased. In order to implement this, the beam current IB of the ion beam which is being implanted is measured all the time by a dose Faraday 22 (see FIG. 3 also) arranged on the side of the upstream of the target 20. The measured beam current IB is supplied to the implanting control device 26 via a current converter 24.
The sweep current I(t) which drives the sweeping magnet 12 results from the shaping of a triangular wave. This waveform shaping is carried out by the implanting control device 26 through a known method described in Japanese Patent Unexamined Publication No. Hei. 9-55179(JP-A-9-55179). For example, using a multi-point beam monitor not shown arranged upstream and downstream side of the target 20, the beam current density distribution in the X direction on the target 20 is estimated, and the triangular wave is shaped so that the distribution approaches constant. Concretely, the triangular wave is shaped so that the sweep speed of the ion beam 4 is decreased at the position where the current density in the current density distribution is desired to be increased whereas the sweep speed is increased at the position where the current density is desired to be decreased, thereby forming a sweep signal S(t). The sweep signal is amplified by a driving amplifier 30 and is supplied to the sweeping magnet 12 as a sweep current I(t).
In the prior art ion-implanting apparatus, the sweep frequency of the ion beam 4 is fixed. The minimum number of times of scanning of the target 20 is also fixed in order to assure the constant uniformity of implanting.
More specifically, generally, assuming that the scan speed in the Y direction of the target 20 is fixed, the implanting uniformity for the target 20 is improved as the sweep frequency of the ion beam 4 becomes high. Namely, as described above, the scan speed of the target 20 is fixed when the beam current of the ion beam 4 is fixed. Therefore, when viewed from the target 20, as shown in FIG. 5, the ion beam is implanted while it draws the locus in zigzag. Therefore, it can be easily supposed that when the sweep frequency of the ion beam 4 becomes low, the area which was not implanted by scanning the target only once is produced.
In an actual implantation, as the case may be, drawing of the ion beam 4 stops momentarily because of discharging in a beam drawing portion (drawing electrode system) of an ion source 2. At this time, the change in the beam current IB of the ion beam 4 is measured by the dose Faraday 22 described above, and a command of stopping the scanning of the target 20 is issued from the implanting control device 26. This intends to prevent the area of the target not implanted from being generated. However, the change in the beam current IB is detected later than the real change by a delay time to (see FIG. 6) of one period at the maximum in the sweep of the ion beam 4. The reason is as follows. When the beam current IB changes at the instant the ion beam 4 passes the dose Faraday 22, this change cannot be measured by the dose Faraday 22 until the ion beam returns to the dose Faraday 22 again. This also applies to the detection at the time of recovery of the ion beam.
In addition, since the scan mechanism 16 has inertia, the scanning of the target 20 cannot be stopped within a zero time. At the time of the recovery of the ion beam 4, the scan speed cannot also be increased to a rated speed within a zero time. An example of the change in the scan speed of the target 20 during that time is shown in FIG. 6. In this example, the stopping time of the ion beam 4 is set for 0.1 sec.
For the above reason, when the drawing of the ion beam 4 is stopped for an instant, the non-uniformity of ion implantation in the Y-direction on the target occurs. An example of the distribution of the quantity of the implanted ion when the phenomenon shown in FIG. 6 occurs is shown in FIG. 7. It shows the example where the target 20 is scanned once, and discharge has occurred once when the ion beam 4 stands at the center of the target 20 in the Y-direction. In this example, the uniformity of implantation is lowered(deteriorated) to 1.156%.
Incidentally, it should be noted that the uniformity of implantation is represented by ("sgr"/M)xc3x97100[%] where the average value of the distribution of the quantity of the implanted ion is M and the standard deviation "sgr", and that of 0% is the best.
The uniformity of implantation is deteriorated as the sweep frequency of the ion beam 4 becomes low. This is because the above delay time to is prolonged correspondingly. The phenomenon of deterioration of the uniformity of implantation occurs likewise when the beam current IB of the ion beam 4 drawn from the ion source 2 varies.
In order to obviate such failure, the conventional ion-implanting apparatus flattens the dense/coarse portion of the above distribution of the implanting quantity by increasing the number of times of scanning of the target 20, thereby assuring prescribed uniformity of implantation. Namely, since the sweep frequency of the ion beam 4 is fixed, the conventional ion implantation apparatus is required to assure a constant minimum number of time of scan necessary to compensate for the above dense/coarse portion of the implanting quantity.
Therefore, although the beam current IB is sufficient when viewed from the ion source 2, the implantation time cannot be shortened since the minimum number of times of scan must be assured. In other words, the throughput of the apparatus cannot be improved.
When the sweep frequency of the ion beam 4 is increased, it cannot be increased excessively. The sweep frequency has a upper limit. This will be explained referring to FIG. 4. The sweep signal S(t) supplied from the implanting control device 26 is amplified by a driving amplifier 30 to provide a sweep current I(t) necessary to drive the sweeping magnet 12.
In such a configuration, the sweep frequency of the ion beam 4 is determined by the following factors.
(1) Magnitude of the sweep current I(t)
It depends on the ion species and energy of the ion beam 4. It also limited by the maximum output current of the driving amplifier 30.
(2) Magnitude of the output voltage V(t) from the driving amplifier 30
It is limited by the maximum output voltage from the driving amplifier 30.
(3) Inductance L of the coil 13 of the sweeping magnet 12
It is determined by the necessary magnetic flux density of the sweeping magnet 12.
Now, assuming that the sweep current when the ion species having a certain mass with certain energy is swept in a desired width by the sweeping magnet 12 is I(t), the output voltage at this time from the driving amplifier 30 is V(t), and the inductance of the coil 13 of the sweeping magnet 12 is L, with the resistance of the coil being negligible, the relationship among these items can be expressed by
V(t)=Lxc2x7dI(t)/dtxe2x80x83xe2x80x83[1]
An example of the relationship of the sweep current I(t) which is a triangular wave with the output voltage V(t) is shown in FIG. 8. The output voltage V(t) has a square waveform. If the sweep frequency of the ion beam 4, i.e. the frequency of the sweep current I(t) is increased twice for example, since the inductance L is a value intrinsic value to the sweeping magnet 12 the necessary output voltage V(t) is also increased twice as seen from Equation [1]. Further, when the sweep current I(t) is wave-shaped as described above in order to enhance the uniformity of implantation in the X-direction on the target, as understood from the example shown in FIGS. 9A and 9B, the output voltage V(t) which is larger (that corresponds to V1 in FIG. 9B) than that in the case of the triangular wave is required. This is because the voltage must be increased during the same period to increase dV(t)/dt. However, if this required V(t) exceeds the maximum output voltage of the driving amplifier 30, the rise in the sweep current I(t) slows down so that the uniformity of implantation in the X-direction is deteriorated.
On the other hand, the ion beam 4 having a lower energy and lighter ion species requires a smaller beam current I(t). This is because such an ion beam can be easily bent.
For the reason described above, in an actual apparatus, the upper limit of the sweep frequency of the ion beam 4 is limited by the energy of the ion beam 4, ion species and the maximum output voltage of the driving amplifier 30. Oppositely speaking, in the conventional ion implantation device, the sweep frequency of the ion beam 4 is fixed so that the energy of the ion beam 4 which can be swept properly and the ion species are limited.
Thus, for example, in order to deal with the ion beam 4 with higher energy, it is necessary to improve the specification such as boosting the maximum output voltage of the driving amplifier 30 or decreasing the inductance L of the coil 13 of the sweeping magnet 12. This requires serious cost and labor. This also applies to dealing with the heavier ion species.
Further, when the sweep frequency of the ion beam 4 is simply reduced in order to deal with the higher energy or heavier ion species, for the reason described above, if the minimum number of times of scanning of the target is not increased, the uniformity of implantation for the target 20 is deteriorated. However, if the minimum number of times of scan is increased, the time of implantation is lengthened so that the throughput of the device is deteriorated.
In view of the circumstance described, the main object of this invention is to provide an ion-implantation method and apparatus which can sweep the ion beam with a wide variety of energies and ion species without changing devices for sweeping the ion beam and shorten the implanting time to improve the throughput of the apparatus.
The ion-implanting method according to this invention comprising a step of changing a sweep frequency of the ion beam to be swept by said sweeping magnet according to at least one of the species and energy of the ion beam and changing the minimum number of times of scanning of the target to be scanned by said scan mechanism according to the changing of the sweep frequency.
The ion-implanting apparatus according to this invention comprises an implanting control device which serves to control sweeping an ion beam by a sweeping magnet and scanning a target by a scan mechanism, and has the functions of changing a sweep frequency of the ion beam to be swept by said sweeping magnet according to at least one of the species and energy of the ion beam and changing the minimum number of times of scanning of the target to be scanned by said scan mechanism according to the changing of the sweep frequency.
Since the sweep frequency of the ion beam is changed according to at least one of the ion species and energy of the ion beam to be swept, dI(t)/dt indicated in the Equation [1] can be varied. Therefore, even if at least one of the ion species and energy of the ion beam is changed, the ion beam can be swept normally within the capability of the devices relative to sweeping of the ion beam. Thus, without changing the devices relative to sweeping of the ion beam, the ion beam with a wide variety of energies and ion species can be swept normally.
Further, the ion beam to be swept having a lower energy and energy and lighter ion species can be more easily bent by the sweeping magnet. Therefore, the sweep current therefor may be reduced and the sweep frequency can be increased correspondingly. Thus, by increasing the sweep frequency, the minimum number of times of scanning of the target can be reduced to assure prescribed uniformity of implantation. Correspondingly, the implanting time can be shortened to improve the throughput of the apparatus.

Ion-implanting method and ion-implanting apparatus


A non-aqueous, reduced toxicity diol based heat transfer fluid is provided comprised of at least one diol that acts as an antidote for ethylene glycol poisoning, such as propylene glycol. The heat transfer fluid may also include corrosion inhibitors that are soluble in the diols used for the heat transfer fluid. The heat transfer fluid may be used as a coolant in internal combustion engines such as automobile engines.

Heat transfer fluids are used in a variety of applications. One common use of heat transfer fluids is as a coolant in internal combustion engines. Most heat transfer fluids that are currently used contain water mixed with ethylene glycol (EG), a hazardous substance that can cause environmental contamination as a result of improper disposal. These fluids can cause dangerous health effects upon humans and other mammals if they are ingested. In addition, adverse health effects can occur due to exposure to used heat transfer fluids as a result of contamination by elemental heavy metal precipitates and toxic inhibitors that are added to prevent water related reactions.
Every year nearly 700 million gallons of heat transfer fluid concentrates are sold in the United States alone, and about 1.2 billion gallons are sold worldwide. Concentrates are formulations to which a substantial water fraction is added to form the actual heat transfer fluid. Much of the heat transfer fluid made from these concentrates replaces similar but spent heat transfer fluid drained from heat transfer systems such as automobile engine cooling systems. It is estimated that a significant percentage of the concentrates are disposed of improperly, resulting in contamination of the environment. Improper disposal by consumers is a major cause of this environmental contamination. Another major source of environmental contamination is leakage, spills and overflows from heavy duty vehicles. Experience with heavy duty vehicles shows that it is common to lose 10% of the engine heat transfer fluid volume after every 12,000 to 18,000 miles of operation due to leaks in the system components, such as the water pump, hose clamps or radiator core. This rate of loss is equal to about one gallon/month for the typical highway truck, which is the equivalent of a leakage rate of one drop per minute. A heat transfer fluid leak rate of one drop per minute is likely to go unnoticed, but can in total add up to a significant loss.
In some operations using heavy duty vehicles, overflows account for far more heat transfer fluid loss than low level leaks at the water pump, hose clamps or radiator core. Overflows occur due to overheating or when an engine cooling system is overfilled. When an engine cooling system is overfilled, operation of the engine heats the heat transfer fluid, causing expansion of the fluid that cannot be contained in the system. Pressure relief valve lines typically allow excess fluid to escape to the ground. Small spills and leaks (less than a gallon) of heat transfer fluid eventually will biodegrade with little impact to the environment. However, before biodegradation occurs, these spills and leaks can present a toxic danger to pets and wildlife.
Current engine coolant formulations typically utilize water as the primary heat removal fluid. The water content of an engine coolant is typically 30% to 70% by volume, depending upon the severity of the winter climate. The second major component of a conventional engine coolant is a freeze point depressant. The freeze point depressant most frequently used is EG, which is added to water in a range from 30% to 70% by volume of the engine coolant to prevent freezing of the water during winter. EG is a diol, a polyhydric alcohol having two hydroxyl (OH) groups. Many diols (such as, for example, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, diapropylene glycol and hexylene glycol) when added to water depress the freezing point of the water and elevate the boiling point of the water. The most commonly used diol in engine coolant formulations is EG, because it has excellent characteristics for that purpose and because it is the least expensive of the diols.
In addition to water and EG, an additive package containing several different chemicals is included. These additives are designed to prevent corrosion, cavitation, deposit formation and foaming, and are each present usually in concentrations of from 0.1% to 3% by weight of the coolant concentrate. The additives are typically mixed with the freeze point depressant to form an antifreeze concentrate, which can be blended with water to form the engine coolant. In some warm weather areas, freezing temperatures are not encountered and a freeze point depressant is not required. In these climates, the engine coolant is typically composed of water with only a corrosion inhibitor package. As an alternative to EG, a formulation composed of the diol propylene glycol (PG) with additives has been used as a freeze point depressant, primarily due to PG's lower toxicity rating as compared to EG.
While it would be desirable to have a single engine coolant formulation that could be used in all climates, attempts to develop a single engine coolant formulation have been unsuccessful due to the need to maintain a delicate balance between the water content and the freeze point depressant in the coolant. In colder climates, a ratio of approximately 70% EG to 30% water by volume is required in engine coolants. In warmer or tropical climates, due to convective heat transfer loss, engine coolants typically require a ratio of approximately 40% EG to 60% water by volume.
A further complication in developing a single engine coolant formulation results from the different requirements of different types of engines. For example, heavy-duty engines require a high concentration of sodium nitrite as an additive to control iron erosion of cylinder liners due to cavitation. Cylinder liner cavitation can occur when a substantial portion of the engine coolant is made up of water. When, for example, a mixture of 50% water and 50% EG is used (50/50 EG/W) in a heavy duty engine, the vapor pressure of the coolant is very high, about 900 mm Hg at 240.degree. F. (132.degree.C.), and under high load conditions large amounts of water vapor are produced on the coolant side of the cylinder wall. As the water vapor ultimately collapses around the cylinder wall, the energy released from the phase change (gas to liquid) impacts the wall and small amounts of iron are eroded. Sodium nitrite is added to limit the amount of vapor impacting the cylinder wall. By comparison, the use of sodium nitrite is not necessary or desirable in light duty engines. The complexity of balancing various water to EG (or PG) ratios and different additive formulations can result in improper freeze protection and clogged radiators and heater cores when the engine coolant is misformulated. As discussed further below, many of these problems are a result of the need for a substantial water fraction in these engine coolants.
Another difference between heavy duty engines and light duty automobile engines is the use of supplemental coolant additives in heavy duty engines to replenish additives that are depleted with service. Supplemental coolant additives are not used or required in passenger cars that have a coolant life of 20,000 miles (32,186 km) to 30,000 miles (48,279 km). Heavy duty service usually demands 200,000 miles (321,860 km) to 300,000 miles (482,790 km) before coolant replacement. The longer coolant service requirement results in the need to periodically replenish the inhibitors in heavy duty engine coolants. Examples of commonly used supplemental coolant additives include sodium nitrite, dipotassium phosphate, sodium molybdate dihydrate, and phosphoric acid.
Supplemental coolant additives must be chemically balanced with the coolant volume, which can be difficult and costly to control properly. Improper balancing of additives can result in severe damage to cooling system components and the engine. If the concentration of the supplemental coolant additives in the coolant is too low, corrosion and cavitation damage to the engine and cooling system components can occur. If, on the other hand, the concentration of supplemental additives is too high, additives can precipitate from the coolant solution and clog radiator and heater cores. A further concern with supplemental coolant additives is that they may, under certain conditions, be difficult to properly dissolve in the engine coolant. If the supplemental additives do not completely dissolve, they may be a source of additional clogging problems in the engine.
Glycols make up 95% by weight of conventional antifreeze/coolant concentrates, and after blending with water, about 30% to 70% by volume of the coolant used in the vehicle.
Because of its relative abundance and lower cost as compared with alternative glycols, conventional antifreezes are almost always formulated with EG. A major disadvantage of using EG as a freezing point depressant for engine coolants is its high toxicity to humans and other mammals if ingested. Toxicity is generally measured in accordance with a rating system known as the LD.sub.50 rating system, which is the amount of a substance expressed in milligrams per kilogram of body mass that, when fed to laboratory rats in a single dose, will cause the death of 50 percent of the laboratory rats. A lower LD.sub.50 value indicates a higher toxicity (i.e., smaller amounts of the substance can be lethal). An LD.sub.50 value of less than or equal to 5,000 milligrams per kilogram of body mass (mg/kg) can classify an antifreeze concentrate as hazardous. Because EG has an LD.sub.50 value of 4,700 mg/kg, EG is considered hazardous by this rating system.
Moreover, EG is a known toxin to humans at relatively low levels. When ingested, EG is metabolized to glycolic and oxalic acids, causing an acid-base disturbance which may result in kidney damage. As reported in Toxic Release Inventory Reporting; Notice of Receipt of Petition, Federal Register, Vol. 63, No. 27, Feb. 10, 1998, the lethal dose of ethylene glycol for a human is approximately 1,570 mg/kg body mass. Consequently, EG is classified by many regulatory authorities as a dangerous material. EG also has the added complication of a sweet smell and taste thereby creating an attraction for animals and children.
Due to the toxicity of EG, in recent years a base fluid concentrate with about 95% PG and additives has been used as a substitute for EG with additives in many antifreeze formulations. PG has an LD.sub.50 value of 20,000 mg/kg as compared to EG's 4,700 mg/kg. PG is considered essentially non-toxic, and it has been approved by the U.S. Food and Drug Administration as a food additive. One impediment to more widespread usage of PG as a base fluid for antifreeze concentrates is its relatively high cost as compared to EG.
All conventional antifreeze concentrates, whether EG or PG based, contain water in their formulations. EG antifreeze concentrates require a small percentage of water in their formulation because EG, by itself and without any water, freezes at +7.7.degree. F. (−13.5.degree. C.). A small amount of water must be added to depress the freezing point. Addition of four percent water by volume to ethylene glycol lowers the freezing point of the mixture to —3.degree. F. (−19.4.degree. C.). The freezing point of PG (by itself and without water) is relatively low, −76.degree. F. (−60.degree.C.). However, because some of the required additives are not readily soluble in either EG or PG, water is added to all conventional concentrate mixtures. Three to five percent by weight water is typically included in coolant concentrates to dissolve certain additives that will not dissolve in glycols. Added water is essential in conventional concentrates to keep the additives dissolved, particularly as the concentrates may be stored for extended periods.
Although three to five percent water is intentionally added to EG and PG concentrates to dissolve water soluble additives, addition of water alone is not effective over long periods of time to maintain the additives in solution. For long term storage, conventional coolant concentrates must be agitated periodically in order to keep the additives in solution until blending of the concentrate with water to make the final coolant mixture. If stored too long as a concentrate (over 6-8 months), one or more of the additives may precipitate from the solution and accumulate in the bottom of the container, forming a gel. The gelled additives will not return to solution, even with agitation. Even when mixed with water in an engine coolant, for example as 50/50 EG/water, the water soluble additives can form a gel if not agitated regularly by running the engine. This can be a severe problem for engines used in stationary emergency pumps and generators as well as military and other limited use engines.
The water added to concentrates to form an engine coolant can also cause formation of potentially hazardous products. Water at elevated temperatures can be highly reactive with the metal surfaces in a cooling system. The water can react with lead and copper materials from radiators, including brass and lead solder. As a result, precipitates of heavy metals, such as lead and copper, can become suspended in the water portion of the circulating coolant in the engine. Water is also highly reactive with light alloys, such as aluminum, and the water fraction of the coolant can generate large amounts of aluminum precipitates, particularly at higher coolant temperatures. Even with the addition of additives to control these reactions, aluminum is constantly lost to the conventional engine coolants containing approximately 50/50 mixtures of EG and water.
Corrosion of metal surfaces in engine cooling systems using conventional glycol/water coolants is also caused by the formation of organic acids in the coolant, such as pyruvic acid, lactic acid, formic acid, and acetic acid. The organic diols, such as EG and PG, can produce acidic oxidation products when in the presence of hot metal surfaces, oxygen from either entrapped air or water, vigorous aeration, and metal ions which catalyze the oxidation process. Moreover, formation of lactic acid and acetic acid is accelerated in coolant solutions at 200.degree. F. (93.3.degree. C.) or above while in the presence of copper. Formation of acetic acid is further accelerated in the presence of aluminum in coolant solutions at 200.degree. F. (93.3.degree. C.) or above. These acids can lower the pH of the coolant. Among the metals and alloys found in engine cooling systems, iron and steel are the most reactive to solutions containing organic acids, whereas light metals and alloys, such as aluminum, are considerably less reactive.
To counteract the effect of organic acids, conventional EG or PG based concentrates include buffers in their formulations The buffers act to maintain the pH of the engine coolant in the range of approximately 10 to 11 as organic acids are formed. Some examples of typically utilized buffers include sodium tetraborate, sodium tetraborate decahydrate, sodium benzoate, phosphoric acid and sodium mercaptobenzothiazole. These buffers also require water in order to enter into and remain in solution. As the buffers in the coolant solution become depleted over time, the water fraction of the coolant reacts with the heat, air and metals of the engine, and, as a result, the pH decreases because of the acids that form.
In addition to buffers, all currently used and previously known engine coolants require inhibitors to control the corrosive effects from the water content of the coolant. The inhibitors must be balanced to avoid interactions with each other that would decrease their individual effectiveness. For example, phosphates and borates can decrease the corrosion protection provided to aluminum by silicates. Moreover, the inhibitors must not be used in excess concentration (in an attempt to extend the depletion time) because that can cause damage to system components due to precipitation resulting in plugging of radiator and heater core tubes. In addition, silicates, silicones, borates and phosphates are chemically abrasive and can erode heat exchanger tubes and pump impellers. Nevertheless, the inhibitors must still exist in a concentration adequate for protecting all of the metals.
All currently used coolant formulations require the addition of water to solubilize additives used as buffers, corrosion inhibitors and anti-foam agents. In addition, these water soluble additives require heat, extreme agitation, and extensive time for the water to react and cause the additives to dissolve. These requirements add significant cost and complexity to the formulation and packaging of antifreeze concentrates. The energy costs and time required for blending, before packaging, are a major factor in the processing costs. Also, because many of these additives may interfere with each other and cause an incomplete solution and failure of the formulation process, the formulating process must be monitored constantly to assure a proper blend.
Thus, the additive package that is included in known coolant concentrate formulations can consist of from 5 to 15, and typically from 8 to 15, different chemicals. These additives are broken down into major and minor categories, depending upon the amount used in an engine coolant formulation:    1 MAJOR (0.05% to 3.0%) MINOR (<0.05%) Buffer Defoamer Corrosion inhibitors Dye Cavitation inhibitors Scale inhibitor Surfactant Chelates
In addition, some of the additives themselves, e.g., borates, phosphates, and nitrites, are considered toxic. Thus, not only do all known coolant concentrate formulations include additives that require heat, extreme agitation and extensive time for the water to react and cause the additives to dissolve, but the additives themselves are sometimes toxic. Further, the additives require complex balancing which accommodates the prevention of interference between the additives, while also preventing the excessive presence of any one additive in the coolant.
The applicant has a co-pending application U.S. Ser. No. 08/991,155 filed on Dec. 17, 1997, which is a continuation-in-part of patent application U.S. Ser. No. 08/409,026 filed on Mar. 23, 1995, each of which are expressly incorporated herein by reference.
Accordingly, it is an object of the present invention to overcome one or more of the drawbacks and disadvantages of the prior art and provide a reduced toxicity, non-aqueous heat transfer fluid.

This patent is subject to a terminal disclaimer.

Non-aqueous heat transfer fluid and use thereof


A novel circuit that generates direct audio from a power supply that uses no power amplifier and that can provide full isolation to any impedance load. It has no power amplifier output stage and has a zero signal-to-noise ratio when there is no signal input because the circuit is designed with MOSFETS that do not conduct unless there is a signal input.

1. Field of the Invention
The present invention relates in general to audio amplifiers and in particular a method and apparatus for obtaining off-line direct audio from a power supply without the use of a relatively high-power amplifier circuit.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
Audio circuits are well known in the prior art and generally utilize an audio amplifying circuit to drive the audio speaker. The audio amplifier is required to a be power audio stage. Such power amplifier circuits are illustrated in U.S. Pat. Nos. 4,409,559 and 4,651,112.
A typical class AB audio amplifier has a power supply and the audio amplifier. The cost of these two units together is significant in the manufacture of an audio output device. There are many switching power amplifiers that attempt to avoid the requirement of an audio power amplifier in the circuit.
Such circuits are shown in U.S. Pat. Nos. 4,763,080, 4,517,522, 4,047,120 and 4,453,131.
Class D amplifiers are always switching at fifty percent duty cycle even when no signal is applied. This causes an inherent noise that increases the signal-to-noise ratio when no signal is applied.
It would be advantageous to have a highly efficient effective audio output circuit deriving its energy from a power supply and avoiding the requirement of having an expensive audio amplifier as the final stage.

Harman International Industries, Incorporated


A combination vehicle seat and stroller for a child is provided with retractable wheel assemblies which forms a substantially flush, smooth bottom surface which will minimize damage to the upholstery of the vehicle. The apparatus is provided with a handle which is retractable when the apparatus is used in a vehicle seat mode, and deployable for use as a stroller. A coupling system is optionally provided for deploying and retracting the wheel assemblies in response to the deployment and retraction of the handle. Forward ones of the wheel assemblies are arranged to pivot so as to provide a steering capability to the stroller, and may be longer than the rear wheel assemblies so as to provide a reclining attitude for the child.

This invention relates generally to equipment for transporting children, and more particularly, to an apparatus which can serve as a vehicle seat for a child, and alternatively as a stroller.
Major campaigns are being waged by lawmakers, insurance companies, and safety conscious groups toward the end of educating motorists of the need for the use of equipment specially designed for transporting children in motor vehicles. Most jurisdictions now mandate that small children must be provided with a vehicle seat which will restrain the child in the event of a collision. This need to provide a child vehicle seat has required parents to carry in their vehicles two relatively bulky items, to wit: a child vehicle seat for use during operation of the vehicle, and a stroller or carriage for use at the destination.
This problem has been addressed by providing devices which function as both, child vehicle seats and strollers on wheels. However, it is a problem with known combination devices that, while the devices are in the vehicle seat mode, they rest on tubular or other frame members which can damage the upholstery of the vehicle. Additionally, in most tubular-framed car seat/stroller devices the stroller wheels, which have been rolled on the ground during use of the device as a stroller, are permitted to come into contact with the upholstery of the vehicle. Thus, such known devices will soil the vehicle's upholstery, and possibly damage same.
One prior art apparatus which avoids all contact by the stroller wheels with the upholstery of the vehicle utilizes a base unit which accommodates the stroller apparatus. The base unit is arranged on the seat of the vehicle, and the stroller portion of the apparatus is accommodated therein and secured thereto by operation of a latching mechanism. This known approach suffers from the disadvantage that a portion of the overall apparatus, i.e., the base unit, remains in the vehicle at all times resulting in inconvenience when the apparatus is transferred from vehicle to vehicle.
It is, therefore, an object of this invention to provide a simple and inexpensive vehicle car seat and stroller combination apparatus which does not damage the upholstery of the vehicle in which it is used.
It is another object of this invention to provide a child's stroller which can be used as a vehicle seat without exposing the vehicle's upholstery to dirt and foreign material which has been collected on the wheels of the stroller.
It is additionally an object of this invention to provide a child's stroller which can be used as a vehicle seat without exposing the vehicle's upholstery to damage from levers, shafts, pins, and mechanisms associated with the wheels of the stroller.
It is also an object of this invention to provide an apparatus can easily be converted between stroller and car seat modes of operation.
It is a further object of this invention to provide an apparatus which is convertible between a car seat and a stroller, and which provides smooth back and bottom surfaces so that it can easily be carried by an individual and supported on the lap of the individual.

Combination child vehicle seat and stroller


Provided are a modular multiplication method with an improved arithmetic operation, a modular multiplier and a cryptograph calculating system having the modular multiplier. The modular multiplication method comprises performing a first arithmetic operation including a first multiplication on a first bit string of a multiplicand and a first bit string of a multiplier and a first reduction for eliminating partial bits of the first multiplication result, performing a second arithmetic operation including a second multiplication on a second bit string of the multiplicand and a second bit string of the multiplier and a second reduction for eliminating partial bits of the second multiplication result, and calculating a modular multiplication result using the result of the first arithmetic operation and the result of the second arithmetic result. The first arithmetic operation and the second arithmetic operation are independently performed.

1. Field
Example embodiments relate to a modular multiplication method and, for example, to a modular multiplication method, a modular multiplier and a cryptograph calculating system having the same for improving a multiplication method and a reduction method to increase a modular multiplication processing speed.
2. Description of the Related Art
Encryption methods may be generally divided into an encryption method using a secret key (or symmetric key) and an encryption method using a public key (or asymmetric key). An encryption method using a secret key is a technique in which two communication devices encrypt and transmit data or decrypt received data using the same secret key. Because the encryption method using a secret key requires the two communication devices to share the same secret key, a safe key transmitting/receiving channel only for the two communication devices is needed.
An encryption method using a public key is a technique in which a communication device encrypts data using a public key of a counterpart's communication device, transmits the encrypted data to the counterpart's communication device and decrypts received data using its secret key that is not opened. Accordingly, it is easy to manage a key in the encryption using a public key because each communication device manages only its own secret key.
Typical public key algorithms include the RSA (Ron Rivest, Adi Shamir, Len Adleman) algorithm, ECC (elliptic curve cryptography) algorithm and DH (Diffie-Hellman) algorithm. A public key encryption system employing the RSA algorithm is most widely used and uses the degree of difficulty of factorization. This RSA encryption system and other encryption systems may be used for electronic signing as well as encryption.
A fundamental arithmetic operation applied to encryption systems including the RSA encryption system is modular exponentiation. Modular exponentiation requires iterative modular multiplication. Modular multiplication generally uses a method of continuously adding a multiplicand based on bits of a multiplier and a method of continuously subtracting a modulus until the result of a multiplication performed on the multiplier and the multiplicand becomes smaller than the modulus for reduction.
For example, to encrypt a plain text M, an RSA encryption system calculates Me using a public key (e,m) (e is an encryption index) composed of two positive integers, divides the calculation result by n and forms a cipher text C using the remainder of the division. In the case of decryption, when the cipher text C is multiplied by d using a secret key (d,n) (d is a decryption index) and the multiplication result is divided by n, the remainder of the division becomes the plain text M. The encryption and decryption are represented as followsC=Me mod m, M=Cd mod n  [Equation 1]
Here, e denotes the encryption index, d denotes the decryption index and n represents a modulus.
As described above, most public key encryption systems are based on modular multiplication or modular exponentiation based on modular multiplication, and thus how efficiently a modular multiplication algorithm is constructed may represent an absolute index of system performance. In order to efficiently construct a modular multiplication algorithm, system performance should be higher, design complexity should be lower, and an area occupied by a circuit should be smaller. However, when one of these factors is improved, other factors may deteriorate. For example, a high-performance modular multiplier may have a large circuit area because it uses a parallel circuit configuration. Accordingly, modular multipliers may be constructed on the basis of trade-off strategy of the aforementioned factors.
In modular multiplying arithmetic, the number of multiplications determines the arithmetic speed, and thus a time required for the arithmetic increases as the number of multiplications increases. Further, the time required for the arithmetic increases according to sequential arithmetic characteristic of a reducing arithmetic. Moreover, the size of hardware for implementing a modular arithmetic device may be affected by interleaving of multiplication and reduction of modular arithmetic because an arithmetic block for multiplication must be separated from an arithmetic block for reduction in the case of a lack of interleaving of multiplication and reduction.
That is, for efficient modular multiplying arithmetic, a scheme of reducing the number of multiplications which the modular multiplier needs to operate or efficient multiplication and reduction in consideration of interleaving of multiplication and reduction is useful. In the case of the widely known Karatsuba algorithm, when multiplying arithmetic is performed on two numbers each having multiple bits, the number of multiplications is reduced to improve a modular multiplication processing speed.
However, conventional modular multipliers are constructed in such a manner that a multiplication block and a reduction block are separated from each other because of a lack of interleaving of multiplication and reduction, and thus hardware configuration is inefficient. Furthermore, in interleaving based modular multiplication arithmetic methods, sequential left-to-right or sequential right-to-left is applied to reduction so as to decrease a modular arithmetic processing speed.

Modular multiplication method, modular multiplier and cryptosystem having the same


A digital multimeter having improved recording functionality is disclosed. The digital multimeter disclosed incorporates a rotary switch, a series of keys and buttons, and a digital display so as to provide highly integrated, programmable and configurable features. Several of these features, either taken alone or in combination, provide significant improvements in ease of use, speed of user operation, and safety associated with use of the instrument.

Multimeters are used for measuring a variety of parameters associated with electrical circuitry, such as currents, voltages, resistance and capacitance. A multimeter can be a handheld device useful for basic fault finding and field service work or a sophisticated bench instrument that can measure with a very high degree of accuracy. The instrument may be implemented with an analog meter deflected by an electromagnet or with a digital display such as an LCD (liquid crystal display) screen. While older analog multimeters might have basic accuracies of 5-10%, modern portable digital multimeters, or DMMs, may have accuracies up to ±0.025%.
Many modern digital multimeters enable a user to save a measurement for later retrieval and analysis. Typically, the instrument is configured such that a user presses a button or otherwise prompts the multimeter to save the measurement as it is taken. In some modern digital multimeters, a hold function is provided that freezes a displayed value once a stable reading is detected. Again, to prompt the hold function, the user must presses a button before taking a measurement and then presses that button once more to release the display.
Digital multimeters incorporate various tools such as the "save" and "hold" features for performing and analyzing different types of measurements and displaying measurement values in a digital format on a screen. Further capabilities and improvements are needed, however, in both hardware and software, to enable users to organize measurement information to be obtained by the instrument so as to operate the instrument efficiently, effectively, and safely.
The headings provided herein are for convenience only and do not necessarily affect the scope or meaning of the claimed invention.

Digital multimeter having improved recording functionality


A center mounted visor assembly for mounting in a vehicle that allows the visor to be rotated downward and upward, from front windshield to side window, and horizontally along the windshield from vehicle side to vehicle center as needed is taught. Provision for vanity power for a vanity light is also taught.

1. Field of the Invention
The present invention generally relates to a sun visor assembly mounted to a vehicle in the center area of the headliner. More particularly, the present invention relates to a center mounted sun visor assembly having a sun visor blade that may be used both in the front and side of a vehicle and which may further move horizontally across the front of the vehicle windshield area.
2. Description of the Related Art
The use of sun visors in vehicles is well known. Attached to the vehicle roof adjacent to the windshield, sun visors are made in various sizes and are made from a variety of materials. Typically sun visors are mounted on a bent arm shaft that is attached to the roof header adjacent to each side of the vehicle. The sun visor may be rotated around the bent arm shaft mounting bezel to allow use both in the front and on the side of the vehicle. However, typically even when both sun visors are positioned in the front of the windshield in a down or use position there is a portion of the windshield in the center area that is not shielded by the sun visor and therefore does not block the glare of the sun from the front seat occupants, most importantly the driver.
To overcome this limitation of the typical corner mounted pair of sun visors at least one patent teaches the use of three sun visors mounted across the front of the windshield. This however, requires the use of an additional piece of equipment, an extra assembly procedure, and added cost.
For example, U.S. Pat. No. 4,521,047 issued Jun. 4, 1985 to Saxman teaches the use of three sun visors mounted across the windshield. There is no provision for horizontal movement across the windshield by any of the three sun visors.
U.S. Pat. No. 6,619,718 issued Sep. 16, 2003 to Tiesler teaches a modular sun visor assembly utilizing a side mounted sun visor arm.
U.S. Pat. No. 6,637,799 issued Oct. 28, 2003 to Tiesler teaches another modular sun visor mounted using a side mount sun visor arm.
U.S. Patent Application Publication No. 2003/0160473 published Aug. 28, 2003 to Tiesler teaches yet another modular sun visor utilizing a side mounted sun visor arm.
Accordingly, it is desirable to provide a sun visor assembly that would allow for the use of only two sun visors and which would allow at least one of said sun visors of being capable of moving in horizontally across the windshield to allow for sun blocking in the center of the windshield.


A variable acuity imager incorporates an array of detection elements for light energy, in the visible, infrared, ultraviolet, or light energy in another region of the electromagnetic spectrum with a means to change the spatial configuration of the array to include “superpixels” by combining energy detected by adjacent elements, thus permitting any number of high-resolution “foveal” regions to be placed within the confines of the focal plane array and moved around at the frame rate of the imaging device. Detectors to measure the pitch, yaw and roll angle rates of background imagery using velocity-sensing circuitry are employed for variation of the foveal regions to accommodate motion of the array.

1. Field of the Invention
This invention relates generally to the field of focal plane imaging devices and, more particularly, to an imaging system employing variable acuity super-pixel imaging that also provides analog signals representative of pitch, roll and yaw angle rates by image motion analysis.
2. Description of the Related Art
Sensing high spatial resolution imagery at very high frame rates, covering wide fields of view while at the same time producing a low data bandwidth so as not to overload data transmission "pipes" is problematic in current imaging systems. As an example, in current "megapixel" imaging systems; high frame rates (e.g., higher than 1000 frames per second) would produce pixel rates in excess of one billion pixels per second; high dynamic range representations of pixels (e.g., 16 bits per pixel, or two bytes per pixel) would produce in excess of two billion bytes per second, or 32 billion bits per second.
Prior imaging systems have been disclosed in U.S. Pat. No. 5,949,483 to Fossum entitled "Active pixel sensor array with multiresolution readout", U.S. Pat. No. 5,430,294 to Mears entitled "Staring focal plane array architecture for multiple applications" and U.S. Pat. No. 5,541,654 to Roberts entitled "Focal plane array imaging device with random access architecture". Fossum discloses use of variable acuity in imaging systems but limits the number of acuity regions and requires that they be of rectangular shape. In addition, spatial agglomeration of pixel values in Fossum's implementation is performed in the column region of the integrated circuit imposing a speed limitation on the number of frames per second which may be produced because all analog pixel values must be shifted out of the unit cell region before such pixel combination is performed. The "windowing" features as represented in Mears' work permits high-speed image sampling, but image regions outside of the desired window are simply ignored.
It is therefore desirable to provide an imager having the capability to permit its pixels be spatially reconfigured and combined, resulting in very high frame rates. It is also desirable to provide the user the ability to produce virtually any spatial configuration. It is also desirable to collect photocharge in temporal "snapshot" mode, guaranteeing temporal coincidence for every pixel in the imager. It is further desirable to permit such updates to take effect without dropping any frames of image data and to produce high-speed, high-relevance imagery, as well as to digitally report its instantaneous spatial configuration. It is also further desirable to provide the ability to mate a variety of detector array types, for applicability to a wide spectral range of useful imaging wavelengths. Also desirable is the ability to measure the roll, pitch and yaw angle rates of background imagery using on-chip circuitry. Finally, it is desirable to perform all desired functions in an integrated circuit that consumes extremely low power and has an extremely low mass.

Method and apparatus for an on-chip variable acuity imager array incorporating roll, pitch and yaw angle rates measurement


An intake plenum is for a marine engine, the marine engine having first and second throttle devices for controlling flow of intake air to the marine engine. The intake plenum has an airbox providing an expansion volume, first and second inlets that convey the intake air in parallel to the expansion volume, first and second outlets that convey the intake air in parallel from the expansion volume to the first and second throttle devices, and first and second Helmholtz-style attenuator devices located at the first and second outlets, respectively. Together the first and second inlets, expansion volume, and first and second Helmholtz-style attenuator devices are configured to attenuate different frequencies of sound emanating from the marine engine via the first and second outlets.

The following U.S. Patents are incorporated herein by reference:
U.S. Pat. No. 10,344,719 discloses an intake system for a marine drive. The intake system comprises a throttle device that receives intake air for combustion; an intake conduit that conveys the intake air to the throttle device, wherein the intake conduit has an upstream inlet end, a downstream outlet end, and a radially outer surface that extends from the upstream inlet end to the downstream outlet end; and an intake silencer coupled to the radially outer surface and configured to attenuate sound emanating from the intake system.
U.S. Pat. No. 10,180,121 discloses an outboard motor having an internal combustion engine and a cowl covering the engine. An air vent allows intake air into the cowl, an air intake duct routes the intake air from the air vent to the engine, and a throttle body meters flow of the intake air from the air intake duct into the engine. A sound enhancement device is located proximate the throttle body. A sound duct is provided which has an inlet end located proximate the sound enhancement device and an outlet end located proximate an outer surface of the cowl. The sound enhancement device is tuned to amplify a first subset of sounds having a desired frequency that are emitted from the throttle body, and the sound duct transmits the amplified sounds to an area outside the cowl. A method for modifying sounds produced by an air intake system of an outboard motor is also provided.
U.S. Pat. No. 9,909,545 discloses an outboard motor having an internal combustion engine powering the outboard motor and a cowl covering the engine and having a vent allowing air under the cowl. A throttle body meters flow of the air into the engine and an intake structure downstream of the throttle body delivers the metered airflow to one or more combustion chambers in a cylinder block of the engine. A sound enhancement assembly in acoustic communication with the intake structure collects sounds emitted by the engine. The sound enhancement assembly is configured to amplify a subset of the collected sounds that have frequencies within a desired frequency range. A method for modifying sounds produced by an air intake system of an internal combustion engine powering an outboard motor is also disclosed. The method includes positioning a sound enhancement assembly in acoustic communication with an air intake passageway located downstream of the engine's throttle body.
U.S. Pat. No. 9,784,218 discloses an air intake system for a marine engine having a throttle body and a throttle plate that is rotatably supported within the throttle body. The throttle plate is rotatable to regulate air flow through the throttle body from a first region on a first side of the throttle plate to a second region on a second side of the throttle plate. An air conduit has an air conduit inlet and an air conduit outlet. A noise cancelling device comprises a pass-through chamber. The pass-through chamber has a chamber inlet that receives the air flow from the air conduit, a chamber outlet that discharges the air flow to the idle air control valve, and a pass-through interior between the chamber inlet and chamber outlet. The pass-through chamber is configured to cancel noise emanating from the idle air control valve.
U.S. Pat. No. 9,359,981 discloses an outboard motor including a system for enhancement of a first subset of sounds having a desired frequency, and a method for modifying sounds produced by an air intake system for an internal combustion engine powering the outboard motor. The method includes collecting sounds emitted in an area proximate a throttle body of the engine. A first subset of the collected sounds, which have frequencies within desired frequency range, are then amplified. The amplified first subset of sounds are then transmitted to an area outside a cowl covering the engine.
U.S. Pat. No. 6,752,240 discloses a sound attenuating system which allows a relatively unobstructed airflow conduit to be associated with chambers that reflect various frequencies of sound back towards the source of the sound. The chambers are arranged in a coaxial association with the primary airflow conduit and are sized to reflect a certain range of frequencies of sound. Holes extend through the airflow conduit, in a radial direction, to place the airflow conduit in fluid communication with the chambers which surround portions of the conduit.

Air intake plenum for attenuating sound from a marine engine


An energy curable lithographic ink composition having an asymptotic relative viscosity of about 0.4 to about 1.5 and a water up-take number of at least about 30%. Also disclosed is a method of improving various rheological properties and increasing the water window of an energy curable lithographic ink by varying the composition of the ink in order to result in an asymptotic relative viscosity of about 0.4 to about 1.5 and a water up-take number of at least about 30%. A method of identifying and selecting an energy curable lithographic ink composition having optimal press performance is also disclosed.

Ultra-violet light curable (UV) and electron beam energy curable (EB) lithographic inks are well established market products in the printing ink or graphic arts market. Examples of energy curable lithographic inks are disclosed in U.S. Pat. No. 5,985,984 and U.S. Pat. No. 6,316,517, which is incorporated herein by reference. Their major benefits are good physical and, chemical resistance properties achieved immediately after curing. Instantaneous cure of UV and EB inks allows for such uses as converting of folding cartons in-line without damaging a printed image (scratches, flaking off, etc.). However, conventional UV/EB lithographic inks suffer from a number of lithographic printing deficiencies such as narrow water window, poor emulsion quality which results in toning and scumming, and a tendency to pile on the offset printing blankets due to poor ink transfer and release which causes defects in the printed image product, and adds cost to a need to change the blankets.
Conventional oil based inks are also well established market products in the lithographic printing market. However, conventional oil based inks have numerous deficiencies as well. For example, the time needed to develop the polymerization qualities of a coated conventional lithographic film is excessive.
One approach has attempted to combine the UV/EB lithographic inks with conventional oil based lithographic inks by applying UV/EB lithographic inks over conventional oil based inks. This approach has not been successful in that it typically results in a significant reduction in gloss and still requires a printed product be coated off-line after the conventional oil based ink is completely dry. Such an approach normally requires a delay of up to 72 hours for the conventional oil based inks to dry completely before the UV/EB coating can be applied off-line, a problem known as "dry back". This is due to the fact that conventional oil based inks dry via a much slower oxidation mechanism requiring multi-step drying and curing. All of this results in added print production expense and production time constraints. Thus, there is a need for a UV/EB lithographic ink that maintains good physical and chemical resistance properties immediately upon and after curing.
Unfortunately, it has always been a challenge to formulate energy curable lithographic inks using acrylate monomers and oligomers as "building blocks". A number of publications and patents have suggested the use of conventional resins such as rosin esters and alkyds in combination with acrylated monomers and oligomers to improve lithographic press performance. However, practical implementation of these ideas has not been widely demonstrated due to serious difficulties in producing stable mixtures of these materials so different in polarity and solubility. For example, UV lithographic inks have a limited water or fountain solution tolerance, which is also referred to as "water window." Water window is defined as an ink's ability to sustain print density despite having an excessive amount of emulsified water. Inks with narrow water window tend to cause many lithographic press problems such as poor ink transfer which results in low print density, toning, piling, scumming, and excessive dot gain. The, overall behavior of lithographic ink regarding these factors defines its lithographic press performance.
Even where a lithographic ink as described above is successfully produced, it does not have a long shelf life and is prone to easy separation under severe printing press shear conditions, causing piling on the rollers and blankets. The prior art does not teach how to formulate a mixture of conventional and UV/EB curable lithographic inks having optimal lithographic press performance. It also does not teach how to effectively identify lithographic inks that offer optimal press performance from, for example, laboratory experiments.
Accordingly, there is a need to provide an energy curable lithographic ink composition having a long shelf life and optimal lithographic performance, including but not limited to a wider water window while still maintaining good lithographic performance on press, such as low dot gain, effective transfer of ink, effective ink trapping, good print contrast, good ink mileage and the absence of toning, scumming, picking, piling and dry back and other properties.


Polyurethane compositions are produced in a two-stage method. In a first step, a diol component with a molecular weight of less than 2000 is reacted with a monomeric diisocyanate with a molecular weight of less than 500 and the unreacted monomeric diisocyanate is removed from this reaction product. In a second step, the resulting high-molecular diisocyanate is reacted with a polyol to produce a reactive prepolymer with isocyanate and groups. The addition of polyisocyanates which are capable of migration and which have a substantially lower vapor pressure than diphenylmethanediisocyanate, improves the addition behavior of the invention polyurethane compositions. Reactive polyurethane compositions of this type are suitable for using as binding agents for reactive one or two component adhesives/sealants, which may optionally contain solvents. These compositions are also suitable for producing reactive hot melt adhesives when suitable polyols are selected. A substantial advantage of these compositions compared to known polyurethane compositions is the considerably lower proportion of monomeric diisocyanates with a molecular weight of less than 500.

1. Field of the Invention
This invention relates to compositions based on polyols and high molecular-weight diisocyanates with a low content of monomeric diisocyanates, and to their production and their use as binders for reactive one- or two-pack adhesives/sealants, reactive hot melt adhesives or solvent-based polyurethane adhesives.
Reactive polyurethane adhesives/sealants, particularly one-pack, moisture-curing systems, generally contain polymers that are liquid at room temperature with urethane groups, optionally urea groups and reactive isocyanate groups. For many applications, these compositions are solvent-free and very highly viscous and/or paste-like, and they are processed at room temperature or at a slightly elevated temperature of between about 50° C. and about 100° C.
2. Description of the Related Art
Reactive, one-pack, moisture-curing polyurethane hot melt adhesives are moisture-curing or moisture-crosslinking adhesives that are solid at room temperature and are applied as an adhesive in the form of their melt, and the polymer components of which contain urethane groups and reactive isocyanate groups. As a result of the cooling of this melt after application and joining of the substrate parts to be bonded, a rapid physical setting of the hot-melt adhesive first takes place by means of its solidification. This is followed by a chemical reaction of the isocyanate groups still present with moisture from the environment to form a crosslinked, infusible adhesive. Reactive hot-melt adhesives based on isocyanate-terminated polyurethane prepolymers are described e.g. by H. F. Huber and H. Müller in "Shaping Reactive Hotmelts Using LMW Copolyesters", Adhesives Age, November 1987, pages 32 to 35.
Laminating adhesives can either be constituted similarly to the reactive hot melt adhesives or they are applied as one-pack systems from a solution in organic solvents; a further embodiment consists of two-pack, solvent-based or solvent-free systems in which the polymer constituents of the one component contain urethane groups and reactive isocyanate groups and, in the two-pack systems, the second component contains polymers or oligomers with hydroxyl groups, amino groups, epoxy groups and/or carboxyl groups. In these two-pack systems the isocyanate group-containing component and the second component are mixed immediately before application, usually with the aid of a mixing and dispensing system.
Reactive polyurethane adhesives/sealants are distinguished by a very high overall performance. In the last few years, therefore, more and more new applications have been opened up for these adhesives/sealants. Compositions for such adhesives and/or sealants are already known from very many patent applications and other publications.
In addition to many advantages, these polyurethane compositions also have some disadvantages caused by the system. One of the most serious disadvantages is the residual monomer content of isocyanates, especially the more volatile diisocyanates. Adhesives/sealants, and especially the hot melt adhesives, are processed at an elevated temperature. The hot melt adhesives, for example, are processed at between 100° C. and 200° C., laminating adhesives between room temperature and 150° C. Even at room temperature, volatile isocyanates such as TDI or IPDI have a not insignificant vapour pressure. This noticeable vapour pressure is particularly serious especially in the case of spray application, since in this case significant quantities of isocyanate vapors can occur over the object being treated, which are toxic owing to their irritant and sensitising action. Protective measures must therefore be taken to prevent health hazards to persons charged with the processing. These measures, such as e.g. the requirement to monitor compliance with the maximum allowable concentration, are expensive. In particular, exhaust ventilation measures for the vapours at the point of formation and delivery are very cost-intensive and also form an obstacle to certain application methods, such as in particular the spray application of reactive polyurethane adhesives/sealants.
The development of reactive polyurethane compositions with a drastically reduced proportion of monomeric diisocyanates is therefore highly desirable for these fields of application, as in some cases this would make it possible to use them in many applications in which their use was not previously possible owing to the workshop hygiene problems mentioned above.
According to the Schulz-Flory statistical model, when diisocyanates with isocyanate groups of approximately equal reactivity are reacted with hydroxyl group-containing compounds, the remaining content of monomeric diisocyanate in the reaction product depends on the NCO/OH ratio of the reactants in the prepolymer synthesis. With an NCO/OH ratio of 2, as is frequently necessary for the prepolymer composition, approximately 25% of the monomeric diisocyanate used remains as a monomer in the prepolymer. If, for example, 10 wt. % diphenylmethane diisocyanate (MDI) is used in a prepolymer synthesis with an NCO/OH ratio of 2, an order of magnitude of approximately 2 wt. % monomeric MDI is found in the prepolymer in accordance with the statistical estimate mentioned above. At 150° C. the pure MDI already has a vapour pressure of 0.8 mbar. While it is true that, according to Raoult's law, this vapour pressure is lower in compositions, it is still higher than the non-toxic range for workshop hygiene. Under the application conditions described above, especially when being applied as a hot melt adhesive over a large area in a thin layer, considerable quantities of the residual monomer therefore pass into the air space above and must be removed by exhaust ventilation. A significant reduction in the monomer content by a power of ten, by reducing the NCO/OH ratio, cannot generally be achieved in practice since the average molecular weight would then increase exponentially and the resulting polyurethane compositions would become extremely viscous and would be impossible to process. In practice, therefore, other routes are taken for prepolymer synthesis. For example, synthesis is performed with a sufficiently high NCO/OH ratio and the monomeric diisocyanate removed in a second step after pre-polymerisation; this can take place by distilling off the unreacted monomeric diisocyanate under vacuum, for example, or by subsequent chemical bonding of the monomeric diisocyanate. Thus, EP-A-316738 describes a process for the production of polyisocyanates containing urethane groups with a urethane group-free starting diisocyanate of no more than 0.4 wt. % by reacting aromatic diisocyanates with polyhydric alcohols and subsequently removing the unreacted, excess starting diisocyanate, the removal of the excess starting diisocyanate by distillation taking place in the presence of an aliphatic polyisocyanate containing isocyanate groups.
EP-A-0393903 describes a process for the production of prepolymers in which, in a first step, monomeric diisocyanate is reacted with a polyol. A catalyst is then added in a sufficient quantity for a considerable proportion of the residual isocyanate functionality to be converted to allophanate functionality. When the theoretical NCO content is reached, the reaction is stopped by rapid cooling and addition of salicylic acid.
WO-95/06124 describes polyurethane compositions with a low proportion of monomeric diisocyanates which are produced by reacting polyols with trifunctional isocyanates and optionally adding monofunctional chain terminators. A disadvantage of this process is the low availability of trifunctional, low molecular-weight isocyanates; the trifunctional homologues of diphenylmethane diisocyanate in particular are not commercially available in pure form.
In the work by V. A. Kudishina and E. F. Morgunova, Sin. Fiz. -Khim. Polim. (1970), part 7, 125–129, cold-curing polyurethane adhesives based on hydroxyfunctional polyesters or polyethers and isocyanate-containing hardeners are described. The isocyanate-containing hardeners are reaction products of tolylene diisocyanate (TDI) or of diphenylmethane diisocyanate (MDI), ethylene glycol and glycerin. It is stated that these hardener components lead to a substantial reduction in the toxicity of the adhesives, although these still produce a quantity of isocyanate of 1.7% in the air space of the corresponding test chamber. These workplace concentrations of isocyanates are no longer tolerable in industrialised western countries under today's standards of workshop hygiene.
Despite the aforementioned prior art, therefore, there is still a need for improved polyurethane compositions with a low proportion of monomeric diisocyanates that are suitable for use as adhesives/sealants, especially for reactive hot melt adhesives. In particular, the raw materials used for these should be readily and cheaply accessible and readily converted, and the adhesion properties should be at least equal to those of the conventional hot melt adhesives.

Adhesion promoters for monomer-free reactive polyurethanes

Henkel Kommanditgesellschaft Auf Aktien (Henkel KGAA)


Apparatus for inspecting the sealing surface area of a container finish that includes a structured light source positioned to direct a collimated line-shaped light beam onto the sealing surface area of a container as the container is moved relative to the light source. The line-shaped light beam at the container sealing surface area has a long dimension orthogonal to the container axis that extends chordally across the sealing surface area, and a narrow dimension tangential to the container axis. A light sensor is disposed to receive portions of the line-shaped light beam reflected from the sealing surface area, and provides an electrical output signal that varies with height or level of the sealing surface with respect to the light source and sensor. The sensor is coupled to associated electronics for providing information indicative of sealing surface height. The elongated dimension of the line-shaped light beam at the container sealing surface area accommodates wobble or misalignment at the sealing surface with respect to the light source and sensor. Furthermore, the elongated radial dimension of the line-shaped light beam at the container sealing surface area produces a reflection on the sensor from any wire-edge or over-press within the container mouth, thus producing at the sensor information indicative of both existence and height of any such wire-edge or over-press.

U.S. Pat. No. 3,313,409 discloses an apparatus for inspecting glass containers in which a starwheel conveys containers in sequence through a series of inspection stations. At one of the inspection stations, selected dimensional parameters of each container are inspected by contacting the container with rollers coupled to sensors, and rotating the container about its central axis so that the sensors provide output signals that vary as a function of variation of the container parameters. Specifically, container height, sealing surface warp and dip, and cocked orientation of the container finish are measured by rollers that engage the container sealing surface as the container rotates. The rollers are coupled to LVDT sensors that provide analog electrical signals indicative of deviations or variations in height (level) at the sealing surface. These signals are fed to appropriate electronics to energize a reject plunger for separating a container from the conveyor line if the measurement signals depart from desired standards and specifications. The rollers in contact with the container sealing surface are subject to mechanical wear, and can cause contamination at the sealing surface. Furthermore, the size of the rollers limits the size of containers in connection with which they may be employed, and the size (resolution) of height variations that can be detected. The moving parts require maintenance and repair. Furthermore, the roller construction is not adapted to measure height of any wire-edge or over-press within the sealing surface lip.
U.S. Pat. No. 4,945,228 discloses an apparatus for inspecting the sealing surface of a container finish that includes a light source positioned to direct light energy onto the container sealing surface as the container is held in stationary position and rotated about its central axis. A camera, which includes a linear array or matrix (area) array of light sensitive elements, is positioned and oriented with respect to the container axis of rotation to receive light energy reflected by the sealing surface, with the camera having an effective field of view limited to an angular portion less than the entire circumference of the container sealing surface. The camera array is scanned at increments of container rotation to develop information indicative of intensity of light at each array element as a function of such increments, and commercial variations at the container sealing surface are detected as a function of such information. The apparatus so disclosed is well adapted to detect commercial variations that affect reflectivity of the container sealing surface, such as line-over-finish variations, blisters, stones and a dirty container finish. However, the apparatus so disclosed is not adapted to measure dimensional parameters of the container finish, such as height of the container sealing surface, warp, dip or cock at the container sealing surface, and/or height of any wire-edge or over-press at the sealing surface.
U.S. Pat. No. 5,489,987 discloses an apparatus for inspecting the sealing surface area of containers that includes a light source positioned to direct a narrow beam of light energy at an acute angle onto the sealing surface area of a container as the container is rotated about its central axis. A light sensor is disposed to receive the narrow beam of light energy reflected from the sealing surface area, and provides an output signal that varies as a function of position of incidence of the reflected light beam on the sensor. That is, the reflected light beam is incident on the sensor at a position that varies with height or level of the sealing surface with respect to the light source and sensor, and the sensor is characterized by providing an electrical output signal that varies as a function of position of incidence of the reflected light beam on the sensor. Variations in height at the sealing surface area are detected as a function of the sensor output signal. In one embodiment, light source/sensor pairs are disposed on diametrically opposed sides of the container axis, and warp, dip and/or cock at the sealing surface of the container is detected as a combined function of variations in position of incidence of the reflected light beams on the sensors as the container rotates.
It is a general object of the present invention to provide an improved apparatus and method for inspecting the sealing surface area of containers for unacceptable commercial variations or defects. Another and more specific object of the present invention is to provide an apparatus and method of the described character that are adapted to inspect the sealing surface area of a container for multiple types of variations in a single operation and at a single inspection station. A further object of the present invention is to provide a method and apparatus of the described character for inspecting both optical and dimensional characteristics of the sealing surface area of a container finish.
It is another object of the present invention to provide an apparatus and method for measuring or determining dimensional characteristics of a container finish, particularly a container sealing surface area, of the type disclosed in the above-noted U.S. Pat. No. 5,489,987, in which the measurement process is characterized by improved immunity to positional variations or wobble at the container sealing surface. Another object of the present invention is to provide a method and apparatus of the described character that attains the foregoing objective while being economical to implement and reliable over an extended operating lifetime. Yet another and more specific object of the present invention is to provide an electro-optical non-contact method and apparatus for measuring height characteristics at the sealing surface of a container, particularly warp, dip and/or cock at the container finish and sealing surface, that in part employ electro-optics already provided for measuring other dimensional parameters at the container finish. A further object of the present invention is to provide a method and apparatus of the described character that, in alternative embodiments, may be implemented at either the hot end or the cold end of a glassware manufacturing system.

Container sealing surface area inspection


A device for applying a medium in the form of a liquid or a paste to a moving substrate, the substrate being a surface of a web of paper, a paper board, fibrous material and/or a transfer element including an application chamber, a first element, a second element and at least one limiting element. The first element is associated with the application chamber on an output side of the application chamber in a direction of movement of the moving substrate. The second element is associated with an input side of the application chamber. The at least one limiting element is associated with a lateral end of the application chamber. The at least one limiting element adjusting a width of application of the medium on the moving substrate. The at least one limiting element having a flexible sealing plate that substantially seals a space between the moving substrate, the first element and the second element. The sealing plate includes a fitted wearing body that is directed toward the moving substrate, with the wearing body being proximate to the first element and the second element.

1. Field of the Invention
The present invention relates to a device for applying a medium in the form of a liquid or a paste to a moving substrate, and, more particularly to a device for applying a medium in the form of a liquid are parts to the surface of a web of paper, board, some other fibrous material or to the surface of a transfer element which conveys the application medium to the web of fibrous material.
2. Description of the Related Art
There are limiting elements that are already familiar from the state of the art, that limit the amount of medium that is applied to an edge of a fibrous web, which are also referred to as edge limiters or even as format limiters. As their name indicates, they are intended to establish a coating-free edge and a specific format or application width on the moving web of fibrous material during its manufacture and/or processing, these limiting amounts are beset with various disadvantages, such as contact with the moving substrate, which can at least partially damage a limiting element on the web by the high friction.
In addition, particles dissolved from the raw material of the web of fibrous material and/or from the application medium can be deposited on the sealing plate. These particles have an abrasive effect which can lead to damage to the moving substrate, that is to say, the web of fibrous material itself and/or the roller which supports it. In the event that the moving substrate is an application roller, damage can also occur to the roller cover. Mention must also be made of damage to the scraper element that is used for the metering and/or evening out of the applied application medium. In particular if the scraper element is a circular cylindrical scraper bar, rotating in a scraper bed, this will lead to local dry running with the negative consequences of damage to the outer surface of the scraper bar and a reduction in the associated quality of the application layer.
What is needed in the art is an improved application device in which the disadvantages associated with the state of the art are avoided.


Systems for wireless communication between a wide bandwidth network node and a narrow bandwidth wireless device are configured to perform operations including determining a maximum channel bandwidth of the narrow bandwidth wireless device, configuring at least two bandwidth parts (BWPs) within a single carrier deployed by the wide bandwidth network node, scheduling a data transmission between the wide bandwidth network node and the narrow bandwidth wireless device within the at least two BWPs, and instructing the narrow bandwidth wireless device to aggregate the at least two BWPs within the single carrier to receive the data transmission.

As wireless networks evolve and grow, there are ongoing challenges in communicating data across such wireless networks. For example, a wireless network may include one or more access nodes, such as base stations, for providing wireless voice and data service to wireless devices in various coverage areas of the one or more access nodes. Further, access nodes may deploy radio air interfaces using one or more frequency bands or sub-bands, which enable wireless devices to connect (or "attach") to each access node. However, a bandwidth of an access node (i.e. a range of frequencies over which the access node is capable of utilizing for wireless communication) may be greater than a bandwidth of a wireless device (i.e. a range of frequencies over which the wireless device is capable of utilizing for wireless communication). For example, if an access node is capable of deploying a 200 MHz channel (as is common in 5G networks), a wireless device may only be able to communicate via channels comprising a maximum bandwidth of 100 MHz. Such an access node may hereinafter be referred to as a wide bandwidth network node, and such a wireless device may hereinafter be referred to as a narrow bandwidth wireless device.
Further complicating this problem is the possibility that the access node is not authorized to utilize the entire bandwidth of a frequency band. For example, certain portions of a frequency band may be available for wireless communication within a specific wireless network. However, configuring an access node to utilize these certain portions still results in narrow bandwidth wireless devices being unable to communicate with such access nodes.

Wireless communication between a wide bandwidth network node and a narrow bandwidth wireless device


A system includes a processor and a memory. The memory stores instructions executable by the processor to receive an image from a stationary camera. The memory stores instructions to determine location coordinates of an object identified in the image based on location coordinates specified for the image. The memory stores instructions to operate a vehicle based on the object location coordinates.

Vehicle collision avoidance systems can use vehicle sensor data and/or broadcast messages from other vehicles to identify an object that is a collision risk and to determine a location of an identified object. However, it is a problem that certain objects can be difficult to identify and/or do not broadcast messages from which a collision risk can be identified. Further, it is a problem that present collision avoidance techniques rely on technologies that are typically expensive and/or difficult to implement. Therefore, it would be beneficial to present a new technical solution for identifying collision risk objects for a vehicle that effectively and efficiently provides collision avoidance for objects that present technologies do not adequately address.

Object location coordinate determination


A method includes collecting physical layer and data layer connectivity information from a plurality of wide area networks using a plurality of mobile devices independently of the wide area networks. A server receives the physical layer and data layer connectivity information, relates the connectivity information to specific wide area networks and to a plurality of geographic locations to create a network statistics database. The server also receives mobile device state information including mobile device location information and predicts that connectivity for a specific mobile device will fall below acceptable criteria based on the network statistics database. The server generates a list of candidate donor mobile devices to serve as data connection sources for the specific mobile device based on the network connectivity information and the mobile device state information and selects a donor device from the list of candidate donor devices based on a weighting algorithm.

Numerous routing protocols have been developed for establishing ad-hoc networks where a mobile device may obtain extended network coverage to a wide area network by using ad hoc network connections with one or more peer mobile devices. For example various routing schemes have been developed around Quality of Service (QoS) considerations because different applications have different requirements pertaining to QoS. That is, such QoS aware routing schemes attempt to find ad-hoc paths based on network throughput, pack delivery ratio, reliability, delay, delay jitter, packet loss rate, bit error rate, and path loss. An ad-hoc network must exhibit self-organization and self-maintaining properties including such required activities such as neighbor discovery, topology organization and re-organization. However such properties often require specific network information that may require access to a specific wide area network statistical information database. Therefore independent ad hoc provisioning of connectivity by individual mobile devices may actually be limited by available information or may be limited to activities within the boundaries of a homogeneous network.

Management of ad-hoc peer-to-peer connections to provide data network access using a plurality of heterogeneous wide area networks