A device and system for remotely interrogating a diagnostic implant device utilizes acoustic energy to power and/or interrogate the device. Acoustic energy is utilized to excite the device from outside the body of a patient. By analyzing the response of the device to such excitation, it is possible to ascertain the condition of the device. Additionally, acoustic energy may be used to provide operating power to the device.

Various types of medical implant devices have been developed over the years. In many instances, such devices enable humans to live longer, more comfortable lives. Implant devices such as pacemakers, artificial joints, valves, grafts, stents, etc. provide a patient with the opportunity to lead a normal life even in the face of major heart, reconstructive, or other type surgery, for example.
It has been found, however, that the introduction of such implant devices can sometimes lead to complications. For example, the human body may reject the implant device which can ultimately lead to infection or other types of complications. Alternatively, the implant device may malfunction or become inoperative. Therefore, it is desirable to be able to monitor the condition of the implant device. On the other hand, it is highly undesirable to have to perform invasive surgery in order to evaluate the condition of the device.
Still further, it is desirable to be able to monitor conditions related to the use of implant devices. For example, in heart patients it may be helpful to know the amount of blood flowing through a stent or graft in order to evaluate the health of the patient. Again, however, it is undesirable to have to perform invasive surgery in order to evaluate such conditions.
Techniques have been developed which enable the function of an implant device to be monitored remotely from outside the body of the patient. These techniques involve including one or more sensors in the device for sensing the condition of the device. The device further includes a small transceiver for processing the output of the sensors and transmitting a signal based on the output. Such signal typically is a radio frequency signal which is received by a receiver from outside the body of the patient. The receiver then processes the signal in order to monitor the function of the device.
While such conventional techniques may be effective in avoiding the need to perform invasive surgery, there are however several drawbacks associated therewith. For example, the transceiver included in the implant device typically includes complex electrical circuitry such as mixers, amplifiers, microprocessors, etc. for receiving an interrogation signal and for transmitting a response signal based on the output of the sensors. Such complex circuitry has a relatively high cost associated therewith. In addition, the complexity of the circuitry increases the likelihood that the device itself may be defective. This would then require further invasive surgery and could even result in physical harm to the patient.
Still another shortcoming with conventional implant devices with sensors included therein is power concerns. Some type of circuit for providing power to the transceiver is necessary. The circuit may be a built-in power source such as a battery, or a circuit which derives operating power from an external excitation signal using magnetic or electromagnetic coupling. In either case, again the complexity of the circuit and/or the need to replace the battery periodically adds to the cost of the device and increases the opportunity for failure or defects.
In view of the aforementioned shortcomings associated with conventional implant devices, there is a strong need in the art for a medical implant device which can be remotely interrogated but which does not require complex electrical circuitry such as mixers, amplifiers, microprocessors, etc. There is a strong need for a medical implant device which carries out a function within a human or other living animal, and can be remotely interrogated simply and reliably. Moreover, there is a strong need for a medical implant device which does not rely on complex energy conversion circuits in order to operate.

Acoustic-based remotely interrogated diagnostic implant device and system


Non-intrusive monitoring and workflow assessment to optimize manufacturing environments are described herein. The systems and method combines computer vision and energy load disaggregation to track worker activity and equipment usage and status. These events are then correlated to optimize workflows and energy efficiency.

Equipment and machine prognosis and operational health monitoring have long been an issue against energy and production efficiency in small and medium factories around the country. These inefficiencies are highly impacted by workers' skills and workflow within the already established manufacturing processes. Small and medium factories have comparably low automated level and machines are less well-maintained as compared to bigger factories. Traditional solutions for this problem usually require the installation of several sensor systems. Different machines may require different sets of sensors. This presents prohibitive cost of installation and maintenance for most factories. Hence, there is a need for a solution describing low-cost non-intrusive load monitoring (NILM) systems that can perform assessment or audit of factories workflow.
Some researchers supported the idea of combining different probabilistic functions to improve the identification of residential energy loads at home. However, those solutions cannot be applied to manufacturing environments to assess efficiency of workflows. The following patents describe other applications in non-intrusive load monitoring. U.S. Pat. No. 4,848,141 discloses a non-intrusive monitor of energy consumption of residential appliances in which sensors, coupled to the power circuits entering a residence, supply analog voltage and current signals which are converted to digital format and processed to detect changes in certain residential load parameters, i.e., admittance. Cluster analysis techniques are employed to group change measurements into certain categories, and logic is applied to identify individual appliances and the energy consumed by each.
US20150012147A1 describes a method and system for use in creating a profile of, managing and understanding power consumption in a premise of a user, wherein said premise comprises two or more power consuming devices comprises measuring, via at least one sensor, aggregate energy consumption at the premise, receiving at a mobile computing device comprising a data processor, said aggregated signal from the sensor, collecting and recording the aggregate signal over a plurality of time resolutions and frequencies, therein to create a predicted aggregate signal for each time x and frequency y, detecting changes in the predicted aggregate signal at time x and frequency y (detected consumption pattern changes) and conveying to at least one of the user, a utility company, and other third party a notification of detected consumption pattern changes.
U.S. Pat. No. 8,812,427B2 teaches a disaggregating power load method comprising receiving time series data representing total energy consumption; identifying distinguishing features in the time series data; and identifying energy consumption constituents of the total energy consumption based on the features. U.S. Pat. No. 9,104,189B2 describes an apparatus and method including acquiring a signal indicative of power consumption; detecting a transient in the signal; extracting a feature indicative of the transient, wherein extracting the feature includes: fitting a plurality of models to the transient, selecting one of the plurality of models as a model for the transient, and defining the feature indicative of the transient based on at least one parameter of the model for the transient; and classifying the transient based on the feature. Additional non-intrusive appliance load monitoring techniques for performing energy disaggregation of a whole-house energy usage profile is disclosed in US20150142695 and WO2013163460A1.

Non-intrusive workflow assessment (NIWA) for manufacturing optimization

THE REGENTS OF THE UNIVERSITY OF CALIFORNIA


Folding bicycle comprising a frame with a front frame portion on which is mounted a front wheel (1) and a rear frame portion (A) on which is mounted a rear wheel (2). The front frame portion includes an upper bar (10), a seat bar (5) and an oblique bar. The rear frame portion comprises at least one seat stay (8), at least one lower bar (9) and the seat bar (5). The oblique bar comprises an upper oblique rod (14) and a lower oblique rod (15). The lower oblique rod (15), the upper oblique rod (14), the upper bar (10) and the seat bar (5) are interconnected by joints (P1, P2, P3, P4), in this order, so as to form an articulated quadrilateral (D) deformable between a folded position and an unfolded position.

There are already many types of folding bicycles. However, most of these bicycles have small wheels, to reduce their size when folded. This has the disadvantage of reducing the comfort and stability of the bicycle when in use.
There are however a few folding bicycles of normal size; by that, we mean bicycles having wheels with a diameter proportionate to the size of the bicycle user. Typically, by today's standards, the diameter of a wheel (more specifically of a tire) recommended for an average adult is between 650 and 700 mm, i.e. between 26 and 28 inches. However, most of these bicycles are actually more dismountable than foldable because their folding requires disassembling all or part of the frame and/or removing one or more wheels. This is the case, for example, of the folding bicycle of patent document U.S. Pat. No. 4,900,047 or patent document EP 211475861.
These bicycles are not satisfactory because the operations required for folding them are complex and their frame may lack rigidity when assembled.
There is therefore a need for a new type of folding bicycle, of normal size, where folding and unfolding operations are simple and do not need to disassemble part of the frame or the wheels of the bicycle.


An electric switch actuating mechanism for use in monitoring fluid control valves such as those used in fire services controls a micro-switch (5) or electronic switch which forms part of an external supervisory circuit. The switch (5) is housed within a common housing (8) with the mechanism. The mechanism comprises a pivoting actuator (24) which is spring (27) biased to a first position and may be pivoted to a second position to actuate the switch (5) by an operator (28). The operator (28) is contacted from externally of the housing by a contact member (38) on a valve spindle (51) when the valve is in the normally open position. The actuator (24) is on a floating pivot (26) and is held in proper operating position by push-rods (36) and pins (37) which are retained in position by a lid (2) of the housing. When the lid is removed the pivot (26) moves to a position wherein movement of the operator (28) will not cause the actuator (24) to operate the switch (5).

This invention relates to a switch actuating mechanism and more particularly to an electric switch mechanism for use in association with an electric switch for monitoring the position of a fluid control valve.
In various fire sprinkler installations it is considered at least desirable and in some instances compulsory due to legislation to monitor that various valves of the hydraulic system are in a normal operating position and are not in some other position that might render them ineffective.
Thus, a water supply line for a sprinkler system may be fitted with an on-off valve which can be put to the off position for various maintenance reasons. However, for the sprinkler system to be effective that valve must be returned to the on position after the maintenance is completed. Since errors might occur it has become at least desirable that a means is provided for monitoring whether that valve is in the on or off position. Such monitoring may be conducted remotely such as at a distant fire station.
It is relatively easy matter to provide an electrical circuit incorporating a switch which can be actuated by some movement of a valve operator to become an open or closed circuit. However, maintenance on the switch itself may be required or the switch may need to be removed for some reason and it is conceivable that a human error might occur rendering the sprinkler system unable to operate but which, to a casual observer, appears to be in full working order.
In many other instances besides fire sprinkler systems similar problems may arise such as at oil refineries and on ships.


A surgical instrument comprising a shaft (1) on which a first handle (3) is formed, a pushing part (2) which is actuated by a second handle (4), and a force accumulator for returning the pushing part (2), wherein the force accumulator and the pushing part (2) are integrally formed.

The present invention relates to a surgical instrument.
A great many surgical instruments are known from the prior art, for example forceps, retractors, clamps, bows, dilators and scissors, in a wide variety of designs and for many different surgical uses.
Surgical instruments are preferably shaped ergonomically and are able to be operated with one hand by an operator.
Surgical instruments of these kinds often have a spring, such that the operator moves the instrument in one direction by applying a certain force, and the opposite movement, i.e. the movement back to a starting position, is effected by a restoring force of the spring.
In the field of surgical instruments, particularly in the field of medical devices in general, an increasing problem in recent times has surrounded the cleaning of often complex devices. As the devices become ever more technically refined, greater effort is required to clean them.
In particular, an immense risk is posed here by the partial regions of medical devices that cannot be sterilized by means of a cleaning process, in particular using cleaning agents.
The problem addressed by the present invention is that of overcoming the disadvantages of the prior art. In particular, a device is to be made available which can be easily dismantled into individual parts and can likewise be easily assembled and which can be easily cleaned in a cleaning process in such a way that it is sterile.


An anaerobic wastewater treatment system includes a recycle tank, a bioreactor tank and a bioselector for recapturing anaerobic microbial consortia particles escaping from the bioreactor tank and returning them to the bioreactor tank. The bioreactor tank receives recycled wastewater feed from a recycle tank and discharges via an overflow outlet treated wastewater and microbial consortia particles to a bioselector. The bioselector is adapted to separate entrained microbial consortia particles and return a feed to the bioreactor tank which including some of the treated wastewater received from the bioreactor tank and the microbial consortia particles received from the bioreactor tank. The bioselector provides a recycle feed to the recycle tank. Overflow from the bioselector provides an effluent of treated wastewater leaving the system.

Anaerobic bioreactors have typically included a bioreactor tank for containing a suspension of naturally forming anaerobic bacteria granules which is a mixture or consortium of bacteria adapted for digesting biological oxygen demand (BOD) or biological waste in wastewater. Those skilled in the art refer to these anaerobic bacteria granules as "microbial consortia particles" or "microbial consortia culture particles" or "active microbial consortia particles" in the case of viable, active anaerobic bacteria granules. The use of such microbial consortia particles for digesting waste in wastewater is well known to those who are skilled in the art. The microbial consortia particles are maintained in a fluidized or expanded or upflow blanket bed by an upwelling flow of wastewater which generally enters the lower end of the bioreactor tank in a generally distributed fashion. Treated wastewater generally exits a typical bioreactor tank in an overflow discharge at the upper end of the bioreactor. An anaerobic bioreactor tank using a culture of microbial consortia particles is most effective if the particles interact with the wastewater in a fluid bed environment. The microbial consortia particles typically have an average size ranging in diameter approximately between 0.5 mm and 3 mm. The microbial consortia particles interact with organic waste and produce various biogas byproducts including methane and carbon dioxide. They also add to their biomass as they digest organic waste. The amount of organic waste in wastewater is measured by biological oxygen demand (BOD) or chemical oxygen demand (COD). Biological oxygen demand (BOD) is a measurement that describes the organic loading in waste water and is well known to those skilled in the art. Typically, the preferred BOD measurement used by those skilled in the art is a five day test for BOD measurement. Chemical oxygen demand (COD) is also a measurement that describes the organic loading in waste water and also is well known to those skilled in the art. COD measurements are more commonly used in the art of anaerobic digestion of organic waste. Methane is not soluble in water, so methane bubbles often form on the surfaces of the microbial consortia particles causing the granules to become buoyant and thus rise within the fluidized bed column. Typically, the interior of the bioreactor tank is provided with various baffle structures typically in the form of inverted conical or inclined plate structures. The purpose of these baffle structures is to contact the microbial consortia particles and impede their migration to the surface of the fluidized bed column. The contact of the granules with baffle structure causes the microbial consortia particles to shed their buoyant methane bubbles and thus impede their migration to the surface of the water and the overflow discharge of the bioreactor. Even with the use of such baffles and other internal selectors or settlers, the tendency of buoyant granules to escape with an overhead discharge is a significant constraint for prior art bioreactors. This constraint reduces the capacity of prior art bioreactors below the biological capacity of microbial consortia particles within a prior art bioreactor. Such internal structures also occupy a significant portion of the volume of prior art bioreactors. This constraint imposed by the need to prevent the escape of microbial consortia particles from a bioreactor tank can limit the capacity, of a bioreactor tank to about 50% of the capacity of a fully charged bioreactor. Accordingly, what is needed is an anaerobic wastewater treatment system in which the potential capacity of a bioreactor tank is substantially fully exploited and wherein the constraint imposed by the need to retain microbial consortia particles is eliminated.

Anaerobic wastewater treatment system and method


A construction kit for building a three-dimensional constellation model is disclosed for viewing of celestial maps. The kit includes a combination of (a) a zenith section having an external shape of a circular form, the back side of said zenith section having a celestial map of the zenith; (b) 6- to 24-in-a-set body plate sections each having a ship's bottom-like shape, each of said body plate sections including an overlap width on its upper edge for bonding to the zenith section, overlap widths on both its right and left edges for forming rib-like projections and an overlap width on its bottom edge for forming an annular flange, each plate section having a celestial map on its back side; (c) a flange-reinforcing plate adapted to bond together the overlap widths provided on the bottom edges of the adjacent body plate sections and (d) reinforcing plates for the rib-like projections to provide greater rigidity and strength to the completed model.

The present invention relates to a three-dimensional constellation model for learning positions, names and others of fixed stars and constellations and a construction kit for assembling such a model.
In general, constellation maps for learning positions, names and others of constellations are two-dimensionally drawn on one sheet of paper, so that it is very difficult to find positions of constellations and stars even when compared with actual stars in the night sky.
In more recent years, there has been proposed a celestial globe, wherein a celestial map has been expressed on the inner surface of a spherical shell, adapted to learn positions and names of fixed stars and constellations by looking into the interior of the spherical shell through an observation window defined at its bottom to compare the celestial map with actual stars in the night sky (see Japanese Patent Laid-Open No. 295591.
The spherical shell comprising a main body of the known celestial globe described above is made of a relatively rigid material such as a metal sheet, plastic or board as described in the specification thereof. It is also described in the above known reference to make the spherical shell and observation window up to a flexible material such as a paper or plastic sheet and to inflate the material like a balloon upon its use. Particular production machines and tools or expert skills are however required to produce such a spherical shell.

Three-dimensional constellation model and construction kit thereof


The simultaneous production of an olefin-free, tert.amyl alkyl, ether-rich fraction an n-pentane-rich paraffin fraction, wherein a charge based on isopentenes is hydrogenated (1) under appropriate conditions to bring about a distribution of the methyl butenes close to thermodynamic equilibrium and then the hydrogenation effluent is treated in an etherification zone (2).

The invention relates to a process for the simultaneous obtaining of a tert. amyl ether (particularly TAME)-rich fraction and a n-pentane-rich fraction from a C.sub.5 fraction containing isopentenes, cyclopentene and cyclopentadiene.
Cracking processes such as steam cracking, viscoreduction, coking and catalytic cracking supply olefin-rich C.sub.5 fractions. Certain of these can contain significant proportions of methyl butenes (isopentenes).
This is in particular the case with steam cracking C.sub.5 fractions, which can contain up to 10% of the mixture 2-methyl-1-butene, 2-methyl-2-butene and 3-methyl-1-butene. This fraction can simultaneously contain up to 20% of diolefins in the form of isoprene, pentadiene and cyclopentadiene. A typical composition of this fraction is given in table 1.
TABLE 1 ______________________________________ % by weight ______________________________________ C.sub.4.sup.- 1 nC.sub.5 26 isoC.sub.5 24 nC.sub.5.sup.= 4.5 Methyl butenes 12.0 Cyclopentene 1.5 Isoprene 13.5 Pentadiene 9.0 Cyclopentadiene 7.5 C.sub.6.sup.+ 1.0 ______________________________________
On the basis of a catalytic cracking C.sub.5 fraction, it is possible to hydrogenate the diolefins into olefins (with the exception of methyl butenes) as is described in the assignee's U.S. Pat. No. 4,724,274. The reaction takes place by passing the charge to be treated (cracking C.sub.5 fraction) with hydrogen and 2 to 50 ppm by weight (expressed as sulphur based on the charge) of at least one compound of sulphur into contact with a supported catalyst containing at least one noble metal of group VIII, at a temperature of 20.degree. to 150.degree. C. and a pressure of 5 to 100 bar.
Moreover, during said hydrogenation stage it is possible with respect to the isopentene to isomerize 3-methyl-1-butene and 2-methyl-1-butene into 2-methyl-2-butene in order to obtain a distribution of these products in proportions close to thermodynamic equilibrium. This composition at equilibrium is shown in table 3.
TABLE 3 ______________________________________ % by weight ______________________________________ 3-methyl-1-butene 0.5 2-methyl-1-butene 12.5 2-methyl-2-butene 87.0 ______________________________________
The steam cracking C.sub.5 fractions differ from the catalytic cracking C.sub.5 fractions by the presence of cyclopentadiene and cyclopentene in a significant quantity (cf. table 1). It has surprisingly been found that the use of a steam cracking C.sub.5 fraction in place of a catalytic cracking C.sub.5 fraction makes it possible to obtain a distribution of isopentenes even closer to thermodynamic equilibrium contitions.
It is also known that fractions rich in methyl butene (isopentenes) are preferred charges for the etherification of iso-olefins having 5 carbon atoms and which are also called isoamylenes by an alcohol (e.g. methanol) for producing a tert. amyl alkyl ether (e.g. tert. amyl methyl ether or TAME). This ether can advantageously be used in mixed form in car fuels in order to improve their research octane number (R.O.N.) and motor octane number (M.O.N.). These etherification processes are described in numerous patents, e.g. U.S. Pat. No. 4,336,407.
In general terms, prior to the etherification stage, the olefin compounds are not separated from the paraffin compounds in particular due to the high separation costs. After etherification the product obtained is a mixture of paraffins, olefins and tert. amyl alkyl ether (e.g. TAME).
It should be noted that only the iso-olefins present in the charge to be etherified are converted into ether. Thus, straight and cyclic olefins and saturated molecules are refractory to the etherification reaction.
The mixture obtained can be used directly in the composition of a car fuel, bearing in mind its properties. However, this has the disadvantage of introducing olefin compounds into the final fuel. It is known that although olefins generally have relatively high research octane numbers (R.O.N.), their motor octane numbers (M.O.N.) are very low. The development and marketing of increasingly high performance and sophisticated engines, as well as the elimination of lead from fuel, made necessary by the introduction of catalytic converters, have led to increasingly severe octane number and in particular M.O.N. specifications for car fuels. The constraints associated with the protection of the environment make it necessary to reduce the olefin content of fuels. Thus, it becomes disadvantageous to introduce these residual olefins into the fuels. This evolution has led to the appearance of separating columns downstream of the etherification units, so as to separate the olefins and paraffins from the ether produced. At present the standard practice consists of using ether for the fuels and recycling the mixture of paraffins and olefins to the steam cracking unit so as to produce other valorizable compounds such as ethylene and propylene. However, it is known that the ethylene and propylene yields obtained during steam cracking are very highly dependent on the quality of the charge to be cracked.
It is generally accepted that the ethylene and propylene yields are much higher when the cracked charge is formed from saturated molecules such as isoparaffins or preferably normal paraffins.

Process for the production of an olefin-free tert, amyl alkyl ether-rich fraction and a n-pentane rich paraffin fraction


A method capable of producing, with industrially realizable production efficiency, microcapsules whose particle diameters are small and whose particle diameter distribution is limited, specifically microcapsules for a heat-sensitive recording material, and a heat-sensitive recording material including the thus produced microcapsules. In this method, microcapsules are produced by the steps of preparing an emulsion from an oil phase that contains a material to be micro-encapsulated and a microcapsule wall material, and an aqueous phase, and micro-encapsulating the materials by using the emulsion, the emulsion preparing step being conducted by using a microreactor having channels whose equivalent diameter is no more than 1 mm, and a heat-sensitive recording material having the thus obtained microcapsules is also provided.

1. Field of the Invention
The present invention relates to a method for producing microcapsules, and more particularly to a method for producing microcapsules for use in a heat-sensitive recording material. The present invention also relates to the heat-sensitive recording material.
2. Description of the Related Art
Various methods for producing microcapsules are known, and among these methods, there is a method in which a material to be micro-encapsulated and a material used for a microcapsule wall are dissolved in an organic solvent, then added to water in which a water-soluble high polymer has been dissolved, and then mixed. This mixture is emulsified into finer particles by using emulsification means such as a high-speed stirrer (dissolver), a homogenizer, or an inline mixer thus obtaining a stable emulsion. Afterwards, a microcapsule wall is formed from the material for the microcapsule wall. As the microcapsule wall, polyurethane and/or polyurea in which polyol and/or polyamine and polyisocyanate are mixed are well known.
A heat-sensitive recording material is known as a recording material using such microcapsules. For example, Japanese Patent Application Laid-Open (JP-A) No. 6-297856 discloses such a heat-sensitive recording material. In this disclosure, in order to emulsify a coupler and a basic substance, these compounds are dissolved in an organic solvent. An aqueous solution of the water-soluble high polymer is added to this mixture while being stirred by a homogenizer.
In the emulsification means such as the high-speed stirrer (dissolver), the homogenizer, or the inline mixer which are described above and which are used in the step of producing microcapsules, a region to which shearing force required for emulsification is applied is limited to the immediate vicinities of emulsification wings. For this reason, there has been caused a problem that the shearing force is not applied uniformly to portions that are apart from or close to the emulsification wings, thus causing the particle diameter distribution of dispersed droplets to be large.
In the heat-sensitive recording material, the particle diameter distribution of microcapsules is desired to be limited so as to form a balanced relationship between heat-sensitivity characteristics and a so-called textile fogging. Since the particle diameter distribution of the microcapsules depends on that of droplets contained in the emulsion during the step of producing the microcapsules, an emulsification method must be used in which the particle diameter distribution of droplets is limited.
With respect to this, as an emulsification method for solving the problem of the particle diameter distribution through the use of the above-described emulsification means, JP-A No. 2630501 discloses an emulsification method in which a so-called xe2x80x9ccylindrical millxe2x80x9d is used. In this emulsification method, the inner cylinder is rotated inside the fixed outer cylinder to pass the mixture of a dispersion solvent and a dispersion through a space between the inner cylinder and the outer cylinder to thereby obtain an emulsion. The mixture is supplied from a tangent direction side surface end portion of the outer cylinder along the circumference thereof. While the mixture is rotated to move into the space between the inner cylinder and the outer cylinder, uniform shearing force is applied to the inner cylinder in the lengthwise direction thereof so that the mixture can be emulsified sufficiently. By this emulsification method, an emulsion whose particle diameter distribution is extremely limited can be obtained. However, since the size of particle diameters of the droplets thus obtained depends on the size of the space between the inner cylinder and the outer cylinder, it is not easy to obtain emulsified particles having no more than a limited particle diameter. Therefore, the particle diameter of the droplets thus obtained is generally limited to about 10 xcexcm, thus making it impossible to obtain droplets whose particle diameters are no more than a few xcexcm.
From a viewpoint of heat color formation characteristics, especially of controlling preferable color formation gradation, microcapsules used for the heat-sensitive recording material needed to have limited particle diameter distribution as described above and to have particles whose particle diameters are generally a few xcexcm or less, and more preferably 1 xcexcm or less. Therefore, it is difficult to adopt an emulsification method using the cylindrical mill. On the contrary, it is desirable to adopt an emulsification method by using microcapsules whose particle diameters are 1 xcexcm or less and whose particle diameter distribution is limited.
A device i.e., a so-called microreactor has been used in a fine chemical field or a biochemical field, and in recent years, has made much progress (see W. Ehrfeld, V. Hessel, and H. Lowe, xe2x80x9cMicroreactorxe2x80x9d, 1Ed. (2000), WILEY-VCH). The microreactor generally refers to a reactor having microscaled channels. For example, while two types of solutions pass through different channels, these solutions come into contact with each other in a form of an extremely thin membrane, in which substances transfer via the interface between layers, and then react with each other. Further, the microreactor is utilized not only for chemical reactions but also for mixing or separating two or more different solutions. Specifically, the microreactor used for mixing is called a xe2x80x9cmicromixerxe2x80x9d. The micromixer mixes these different solutions by the steps of forming liquid films of these different solutions which are to be mixed such that the films are superposed, and passing the liquid films through narrow passages. For example, by using the oil phase and the aqueous phase as liquids, an emulsion can be prepared.
WO00/62913 proposes a dispersion device (micromixer) for conducting dispersion by using such a microreactor. This dispersion device is used by a method in which fluids which are formed of liquid A and liquid B are passed through respective microscaled channels and then divided into spatially separate liquid layers (liquid films). Then, the separate fluids are combined with each other, passed through narrow passages, and the liquid A and the liquid B are dispersed into fine droplets, during which a mechanical oscillator is used to promote the formation of droplets.
However, in the emulsification step for producing microcapsules, especially that used for the heat-sensitive recording material, a technique for conducting emulsification by means of a microreactor, and for producing microcapsules having a target particle diameter and a target particle diameter distribution is not known. This is because of the below described reason. Namely, in the production of microcapsules, during the emulsification step, a water-soluble high polymer compound is usually added to an aqueous phase to be added to an oil phase for stabilizing the dispersion of droplets. However, the aqueous solution to which the water-soluble high polymer compound was added has a high viscosity, thus making it impossible to increase the processing amount from a viewpoint that pressure loss is likely to occur inside the micromixer. Further, emulsification cannot usually be carried out without adding the water-soluble high polymer compound to the aqueous phase.
An object of the present invention is to provide a method for producing microcapsules whose particle diameters are small and whose particle diameter distribution is limited, with industrially realizable production efficiency, specifically microcapsules used for a heat-sensitive recording material, and the heat-sensitive recording material containing microcapsules produced through the use of this method.
The object can be achieved by providing a method for producing microcapsules and a heat-sensitive recording material described below.
A first aspect of the present invention is a method for producing microcapsules comprising the steps of: (1) preparing an emulsion from an oil phase that contains at least a material to be micro-encapsulated and a microcapsule wall material, and an aqueous phase; and (2) carrying out micro-encapsulation by using the emulsion, wherein the step of preparing the emulsion is conducted by means of a microreactor having channels whose equivalent diameters are no more than 1 mm.
A second aspect of the present invention is a method for producing microcapsules, comprising the steps of (1) preparing an emulsion from an oil phase that contains at least a material to be micro-encapsulated and a microcapsule wall material, and an aqueous phase; and (2) carrying out micro-encapsulation by using the emulsion, wherein the aqueous phase contains at least a surface active water-soluble high polymer compound and has a viscosity of no more than 40 cp, and the step of preparing the emulsion is conducted by means of a microreactor having channels whose equivalent diameters are no more than 1 mm.
A third aspect of the present invention is a heat-sensitive recording material having a heat-sensitive recording layer on a support, wherein the heat-sensitive recording layer contains microcapsules obtained by the method for producing microcapsules, and a color-developing agent.
A microreactor used in the present invention is a reactor having microscaled channels (see W. Ehrfeld, V. Hessel, and H. Lowe, xe2x80x9cMicroreactorxe2x80x9d, 1Ed. (2000), WILEY-VCH for further details).
Since the channels of the microreactor are microscaled, both the size and the flow rate thereof are small and Reynolds number is no more than 200. Accordingly, a reactor having microscaled channels is not a device which is controlled by turbulent flow like in an ordinary reactor but a device which is controlled by laminar flow.
In those devices controlled by laminar flow, even when flows of two solutions are made to contact with each other, the two solutions can be mixed only by diffusion via the interface therebetween. Since a microscaled space has a large specific interface area, the space can be advantageously used for diffusion mixing at the interface at which larminar flows come into contact with each other. The time the diffusion mixing takes depends on a sectional area of the interface at which the two solutions contact with each other, and a thickness of a solution layer. In accordance with xe2x80x9cdiffusion theoryxe2x80x9d, time (t) for the mixing (mass transfer) is represented by the following equation:
t=deq2/D
(wherein the definition of deq will be described hereinafter and D is mass diffusivity). Therefore, the smaller the channel width, the faster the time for mixing. Namely, when an equivalent diameter of a channel becomes {fraction (1/10)}, time for mixing becomes {fraction (1/100)}. Molecular transportation, molecular reaction, or molecular separation in a microscaled space can be conducted promptly due to spontaneous behavior of the molecules without using mechanical stirring.
For such reason, reaction speed under laminar flow of the microreactor according to the present invention is said to be higher than that under turbulent flow via a conventional macroreactor. In the case of the macroreactor, excessively high reaction speed is not necessarily advantageous for the control of reaction. However, in the case of the microreactor, since reaction is conducted basically at the flows, residence time inside the reactor can be controlled and temperature control is also facilitated as will be described later. Consequently, there is a high possibility that reaction selectivity will be noticeably improved. Further, since phase separation becomes facilitated, two-phase system reaction or separation refinement of products is enabled by using such characteristics.
Besides the above-described characteristics, since the microreactor has an extremely small reaction zone, the microreactor is also characterized by the ability to conduct high-temperature or high-pressure reactions safely by using metallic or ceramic materials. For example, with the microreactor, the oxidation reaction due to the generation of hydrogen peroxide from oxygen and hydrogen is possible, though this reaction is risky and almost impossible with the use of a typical reactor.
Reactivity of the microreactor is affected by the equivalent diameter of a flow passage (channel). The equivalent diameter is also referred to as a xe2x80x9cnominal (right) diameterxe2x80x9d, which is the terminology used in the mechanical engineering field. Assuming that a circular pipe is equivalent to a pipe (channel in the present invention) having a suitably selected cross-sectional configuration, the diameter of the equivalent circular pipe is referred to as an equivalent diameter and defined as:
xe2x80x83Deq=4A/p
by using A: a cross section of a pipe and p: wet perimeter length (circumferential length) of the pipe. When applied to the circular pipe, the equivalent diameter is equal to the diameter of the circular pipe. The equivalent diameter is used to estimate the flow or thermal transfer characteristics of the pipe on the basis of data from the equivalent circular pipe, and then expresses the spatial scale (representative length) of the phenomenon. The equivalent diameter of an equilateral square pipe whose one side is a is defined as deq=4a2/4a=a, that of an equilateral triangle pipe whose one side is a is defined as deq=a/{square root over (3)}, and that of the flow whose passage height between parallel flat plates is h is defined as deq=2h (see xe2x80x9cMechanical Engineering Dictionaryxe2x80x9d edited by The Japan Society of Mechanical Engineers (1997), published by Maruzen Co., Ltd.)
The smaller the equivalent diameter of a channel, the larger the surface area (specified surface area) per unit of volume. Therefore, if the channel is microscaled as in the present invention, since the specified surface area becomes large, a thermal transfer efficiency via a vessel wall of the channel becomes remarkably high. Thermal transfer time (t) in the fluid that flows into the channel is represented by the following equation:
t=deq2/xcex1 (xcex1: thermal diffusivity)
Therefore, the smaller the equivalent diameter, the shorter the thermal transfer time. Namely, when the equivalent diameter becomes {fraction (1/10)}, the thermal transfer time becomes {fraction (1/100)}. If the equivalent diameter is microscaled, the thermal transfer speed is extremely high.
In the method of producing microcapsules, the present invention is characterized in that the emulsification step i.e., one of the steps for producing microcapsules is conducted by a microreactor having channels whose equivalent diameter is no more than 1 mm.
Since the emulsification step in the method for producing microcapsules of the present invention uses the microreactor described above, microcapsules whose particle diameters are small and whose particle diameter distribution is limited can be produced. Further, since the aqueous phase used in the emulsification step is water or an aqueous solution of a low molecular surfactant and has a low viscosity, it is possible to increase a flow rate inside the microreactor and improve the efficiency with which the emulsion is prepared.
Further, in accordance with another aspect of the present invention, since an aqueous phase used in the emulsification step uses an aqueous solution of a water-soluble high polymer compound which has a relatively low viscosity of 40 cp or less and which is at least surface active, a flow rate inside the microreactor and the amount in which emulsion is treated can increase.
An oil phase and an aqueous phase are passed through the above-described channels each having an equivalent diameter of 1 mm or less to thereby form liquid films of the oil phase and the aqueous phase. These liquid films are passed through narrow passages to mix the oil phase and the aqueous phase and thereby form emulsion. Specifically, the liquid films are formed such that the oil phase liquid film and the aqueous phase liquid film are superposed. For example, as disclosed in FIG. 1 or FIG. 3 of WO00/62913 described above, a channel for an oil phase and a channel for an aqueous phase are alternately formed. The oil phase and the aqueous phase are passed through the respective channels. Accordingly, spatially separated liquid films are formed. The separated fluids are then combined with one another and passed through narrow passages. Consequently, the oil phase can be dispersed into the aqueous phase in the form of finer droplets. Examples of such microreactors are also disclosed in WO97/12665, WO97/17130, WO97/17133, WO97/28894, and WO98/33582.
In the emulsification of the present invention by using the microreactor, since the equivalent diameter of the channel is set to 1 mm or less, excellent emulsification can be conducted to obtain an emulsion which is formed of droplets each having a small particle diameter and a limited particle diameter distribution. The equivalent diameter of the channel is preferably 10 to 500 xcexcm, and particularly preferably 20 to 300 xcexcm. The length of the channel is not particularly limited, however, it is preferably 10 to 500 mm, and particularly preferably 10 to 500 mm. (In this specification, xe2x80x9ctoxe2x80x9d represents a range including values written before and after xe2x80x9ctoxe2x80x9d as a maximum value and a minimum value, respectively.)
Due to a numbering-up of the many channels used in the present invention as needed, a processing amount of the channels can be increased.
Further, the time the fluids stay inside the channels is generally no more than 1 hour, preferably no more than 10 minutes, and more preferably 1 second to 5 minutes.
The channels of the present invention are formed on a solid substrate by using a fine processing technology. Examples of materials used include: metal, silicone, teflon, glass, ceramics, or plastic. When heat resistance, pressure resistance, and solvent-resistance are required, preferable materials are silicone, teflon, glass, ceramics, or plastic, and a particularly preferable material is metal. Examples of metals include: nickel, aluminum, silver, gold, platinum, tantalum, stainless steel steel, hastelloy (Ni-Fe-based alloy), or titanium. However, stainless steel, hastelloy, or titanium which is corrosion-resistant is preferable.
In a conventional batch reactor, when an acid or the like is treated, a device having glass-lined metal (such as stainless steel) surface is used. However, in the microreactor also, glass can be coated on a metal surface. In accordance with the purpose, not only glass but also another metal or other materials can be coated on the metal surface. Also metal or glass can be coated on the surface of a material other than metal (e.g., ceramics).
The channels of the device (microreactor) according to the present invention can be subjected to a surface treatment in accordance with the purpose of the device. Particularly when an aqueous solution is controlled, since there is sometimes caused a problem that the glass or silicon absorbs the sample, the surface treatment is important. It is desirable to realize the fluid control in micro-size channels without incorporating therein movable parts for which a complicated producing process is required. For example, hydrophilic and hydrophobic regions may be formed inside the channels by the surface treatment so that the fluid can be controlled by making use of the difference between surface tensions acting on the interface between the hydrophilic and hydrophobic regions.
Typical examples of the fine processing technology for preparing a channel include: a LIGA technology using an X-ray lithography, a high-aspect ratio photolithography using EPON SU-8, a micro discharge processing method (xcexc-EDM), a high-aspect ratio processing method of silicone by Deep RIE, a Hot Emboss processing method, a light molding method, a laser processing method, an ion beam processing method, and a mechanical micro-cutting processing method using a micro tool made by a hard material such as diamond. These methods can be used singly or in combination. Preferable examples of the fine processing technologies include: the LIGA technology using the X-ray lithography, the high-aspect ratio photolithography using EPN SU-8, the micro discharge processing method (xcexc-EDM), and the mechanical micro-cutting processing method.
When the microreactor of the present invention is assembled, a bonding technology is often used. An ordinary bonding technology is largely divided into a solid phase bonding and a liquid phase bonding. Bonding methods in general use include: a solid phase bonding method such as a press-contact or diffusive bonding; and a liquid phase bonding method such as welding, eutectic bonding, soldering, or adhesion. Further, it is desired to assemble the microreactor by a highly accurate bonding method in which size accuracy can be maintained while preventing a fine structural body such as a channel from being destroyed due to quality deterioration or deformation of a material when heated at high temperature. Examples of technologies for such a method include: a silicone direct bonding, a positive electrode bonding, a surface activation bonding, a direct bonding using hydrogen bonding, a bonding using an aqueous solution of HF, an Au-Si eutectic bonding, or a void-free bonding.
In order to emulsify oil phase droplets into the aqueous phase by flowing the oil phase and aqueous phase solutions into the channels of the microreactor, a fluid control function is needed to introduce the oil phase and the aqueous phase into the channels. Specifically, since the behavior of the fluid in a fine region has properties different from those of a microscale, a control method appropriate for the microscale should be considered. A fluid control method is classified into a continuous flow system and a droplet (liquid plug) system according to the formation, while it is also classified into an electric driving system and a pressure driving system according to the driving force.
A more detailed description of these systems will be given hereinafter. The most widely used system as a formation for treating a fluid is the continuous flow system. When the flow is controlled in the continuous flow system, generally, the entire portion inside the channel of the microreactor is filled with a fluid, and the fluid as a whole is driven by a pressure source such as a syringe pump that is provided outside the channel. In this case, the continuous flow system has such a merit that the control system can be realized with a relatively simple set-up. However, this operation which requires replacing the solution is difficult. There is a difficulty in that there is a limited degree of freedom with respect to the structure of the system and there is an excessive amount of dead volume because a driving medium is the solution itself.
As a system which is different from the continuous flow system, there is provided the droplet (liquid plug) system. In this system, droplets partitioned by air are made to move inside the reactor or inside the channel leading to the reactor, and each of the droplets is driven by air pressure. During this process, a vent structure for allowing air between droplets and channel walls, or air between the droplets as necessary, to escape to the outside and a valve structure for maintaining pressure inside the branched channels independently from pressure at other portions must be provided inside the reactor system. Further, a pressure control system that is formed by a pressure source or a switching valve must be provided outside the reactor system in order to move the droplets by controlling the pressure difference. Thus, in the droplet system, the structure of the device or the configuration of the reactor becomes rather complicated, but the system can be more freely structured.
In general, as a driving system for controlling the fluid, the electric driving system in which an electroosmotic flow is generated due to the application of high voltage to both ends of a channel to thereby move a fluid and the pressure driving system in which pressure is applied to a fluid by a pressure source provided outside a channel to thereby move the fluid are widely used. For example, it is known that fluid behavior in these systems is different, and a flow rate profile in the cross section of a channel is flat in the electrical driving system, while it is hyperbolic in the pressure driving system in which the fluid flows fast at the center of the channel but slowly at the wall surface thereof. The electrical driving system is more appropriate than the pressure driving system for moving a sample plug without changing its configuration. In the case of the electrical driving system, since the inside of the channel must be filled with a fluid, this system must assume the form of the continuous flow system. However, since operation of the fluid is electrically controllable, a relatively complicated treatment is realized in which density slope with time is formed by sequentially changing the mixing ratio of two different solutions. In the case of the pressure driving system, the fluid can be controlled in spite of electric properties and there is no need to consider a secondary effect such as heat generation or electrolysis. As a result, this system hardly affects the substrate and thereby has a wide scope of application. Conversely, since a pressure source must be provided outside the channel, or operational response characteristics vary in accordance with the size of the dead volume of a pressure system, a complicated treatment must be automated.
A method which is used as a fluid control method is appropriately selected in accordance with the purpose. However, the pressure driving system in the continuous flowing system is preferable.
Temperature control of the microreactor can be performed by accommodating the entire device in a vessel whose temperature was controlled or by incorporating in the device a metal resistance wire, or a heater structure such as polysilicone. This metal resistance wire or the heater structure is used for heating, while a thermal cycling by natural cooling can be used for cooling. Temperature is sensed as described below. In the case of the metal resistance wire, another resistance wire which is the same as that of the heater is incorporated in the metal resistance wire to detect the temperature on the basis of the change of the resistance value. In the case of polysilicone, a thermocouple is used to detect the temperature. Further, the microreactor can be heated or cooled from the outside thereof by contacting a Pertier element with the microreactor. Selection of a method depends on the purpose of the microreactor or the material of the reactor body.
In order to increase a processing amount, it is possible to use an array-type reactor (mixer array) in which the above-described microreactors which are disposed parallel to each other were incorporated in the device.
Production of Microcapsules
A description of a method for producing microcapsules according to the present invention will be given hereinafter. In the method for producing the microcapsules of the present invention, after the emulsion was prepared from an oil phase and an aqueous phase as described above, a microcapsule wall material is made to react with the emulsion so that a microcapsule wall is formed. When the microcapsule wall is formed, if an isocyanate compound is used as the material for the microcapsule wall, after emulsification, the reaction for forming the microcapsule wall can be promoted by adding a polymerizable reaction catalyst of the isocyanate compound or by raising the temperature of emulsion.
Other than water, an aqueous solution of a low molecular surfactant can be used as the aqueous phase. A low molecular surfactant having a molecular weight of no more than 1000 is used without a particular limit. Further, a formalin condensed surfactant such as an aromatic sulfonate or an aromatic carbonate, or an alkylglucosido surfactant which are shown below can be used.
wherein R represents an alkyl group having 1 to 4 carbon atoms, X represents SO3xe2x88x92or COOxe2x88x92, M represents sodium or potassium, and q represents integers of 1 to 20.
The surfactant includes a structure in which an aromatic sulfonic acid or an aromatic carbonic acid such as a benzene sulfonic acid, a benzoic acid, a naphthalene sulfonic acid, or a naphthalene carbonic acid and its derivatives are formalin-condensed. A mean polymerization degree of 2 to 10 is preferable. The aromatic ring is preferably one to which an alkyl group or a substituted alkyl group having 1 to 4 carbon atoms was added. A plurality of surfactants can be mixed and used.
wherein n represents integers of 0 to 2, R represents an alkyl group having 4 to 18 carbon atoms whose chains can be straight or branched. i-butyl, n-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-decyl, n-dodecyl, n-hexadecyl, n-octadecyl, and a branched octadecyl. In an industrial producing method, n is a composition in which 1 to 2 components are mixed and which contains monosaccharide glycoside of unit 0 as a main component, but such composition ratio of these components does not affect the effect of the present invention. Further, a combination of two or more different alkyl groups does not deteriorate the effect of the present invention.
The content of the surfactant in aqueous phase is 0.001 to 10%, and preferably 0.01 to 6%.
Another aspect of the present invention uses an aqueous solution which contains at least a surface active water-soluble high polymer compound for the aqueous phase. Examples of an at least surface active water-soluble high polymer compound include: polyvinyl alcohol and its modified substances, polyacrylic acid amide and its derivatives, ethylene-vinyl acetate copolymer, styrene-maleic anhydride copolymer, ethylene-maleic anhydride copolymer, isobutylene-maleic anhydride copolymer, polyvinylpyrolidone, ethylene-acrylic copolymer, vinyl acetate-acrylic copolymer, carboxyl methyl cellulose, methyl cellulose, casein, gelatin, starch derivatives, gum arabic, sodium alginate, and the like. Preferably, these water-soluble high polymers do not react with isocyanate compounds or have a relatively low reactivity therewith. For example, like gelatin, a water-soluble high polymer compound having a reactive amino group in the molecular chain thereof must be previously made nonreactive.
Viscosity of the aqueous phase must be no more than 40 cp, preferably no more than 20 cp, and more preferably no more than 10 cp. If the viscosity of the aqueous phase is more than 40 cp, pressure loss is caused inside the microreactor, thus making it impossible to obtain a desired processing amount. Accordingly, the viscosity must have no more than the above-described range.
In the above-described micro-encapsulation step, preferably, an aqueous solution containing at least a surface active water-soluble high polymer compound is further added to the emulsion, and afterwards, a material for a microcapsule wall is made to react with this mixture to thereby form the microcapsule wall. This aqueous solution is added to prevent the rare occurrence of aggregation of the microcapsule particles during the reaction. The aqueous solution to be added to the emulsion is appropriately added such that microcapsules dispersion after reaction has a solid matter density of 5 to 50%, and preferably 10 to 40%. Further, the aqueous phase to be added to an oil phase during the emulsification may be referred to as a xe2x80x9cfirst aqueous phasexe2x80x9d, and the aqueous phase to be added to the emulsion during micro-encapsulation may be referred to as a xe2x80x9csecond aqueous phasexe2x80x9d.
In the same manner as described above, a water-soluble high polymer compound which is contained in a first aqueous phase is used for the at least surface active water-soluble high polymer compound to be added to a second aqueous phase.
Examples of the at least surface active water-soluble high polymer compound to be added to the second aqueous phase include: polyvinyl alcohol and its modified substances, polyacrylic amide and its derivatives, ethylene-vinyl acetate copolymer, styrene-maleic anhydride copolymer, ethylene-maleic anhydride copolymer, isobutylene-maleic anhydride copolymer; polyvinylpyrolidone, ethylene-acrylic copolymer, vinyl acetate-acrylic copolymer, carboxyl methyl cellulose, methyl cellulose, casein, gelatin, starch derivatives, gum arabic, sodium alginate, and the like. Preferably, these water-soluble high polymer compounds are nonreactive with isocyanate compounds or have a relatively low reactivity therewith. For example, like gelatin, a water-soluble polymer compound having a reactive amino group in the molecular chain thereof needs to be previously made nonreactive.
The concentration of the water-soluble high polymer compound contained in the second aqueous phase is 1 to 20%, and preferably 2 to 10%.
Production of Heat-Sensitive Recording Material
A description of a method for producing a heat-sensitive recording material by using the method for producing microcapsules as in the above-description will be given hereinafter. A heat-sensitive recording layer of the heat-sensitive recording material includes microcapsules for encapsulating therein a diazonium salt compound or an electron donating dye precursor as a color-forming component. Further, the heat-sensitive recording layer includes microcapsules as in the above-description, and a coupler or an electron accepting compound which is a color developer which develops a color in accordance with the color-forming component contained in the microcapsules. The color developer is emulsified or solidly dispersed into particles. The heat-sensitive recording layer is formed by coating on a support a mixture of microcapsules solution and a color-developing solution which are prepared as will be described later.
Since the heat-sensitive recording material of the present invention uses a microreactor during the emulsification step for producing the microcapsules, the material has a high color-forming density and little texture fogging when stored long term.
Microcapsules containing therein a diazonium salt compound or an electron donating dye precursor is produced by the steps of preparing an oil phase containing the diazonium salt compound or the electron donating dye precursor and a material for a microcapsule wall, and an aqueous solution; and emulsifying the oil phase and the aqueous phase by using a microreactor having channels whose equivalent diameters are no more than 1 mm.
Then, the resultant emulsion is micro-encapsulated to obtain microcapsules. During this process, as described above, it is preferable that the aqueous solution containing the water-soluble high polymer compound which is surface active is added to the emulsion, and then micro-encapsulated.
The oil phase is prepared by dissolving the diazonium salt compound or the electron donating dye precursor and the material for a microcapsule wall, and as necessary, various additives as well, in an organic solvent which is refractory or insoluble in water. Further, the aqueous phase uses only water, or is one in which various low molecular surfactants were dissolved in water.
Examples of the organic solvents include: low boiling point auxiliarly solvents such as acetate, methylenechloride, and cyclohexane and/or carboxylic acid esters such as ester phosphate, ester phthalate, acrylic ester, methacrylate, and the like, fatty acid amide, alkylated biphenyl, alkylated taphenyl, alkylated naphthalene, diallylethane, chlorinated paraffin, alcohols, phenols, ethers, monoolefins, and epoxies. Specific examples thereof include: high boiling point oils such as tricresyl phosphate, trioctyl phosphate, octyl diphenyl phosphate, tricylohexyl phosphate, dibutyl phthalate, dioctyl phthalate, dilaurate phthalate, dicyclohexyl phthalate, butyl olefinic acid, diethylene glycol benzoate, dioctyl sebacate, dibutyl sebacate, dioctyl adipic acid, trioctyl trimellitic acid, acetyl triethyl citric acid, maleic octyl, maleic dibutyl, isoamyl biphenyl, chlorinated paraffin, diisopropylnaphthalene, 1,1xe2x80x2-ditrilethane, 2,4-ditertiaryamylphenol, N,N-dibutyl-2-buthoxy-5-tertiaryoctylaniline, hydroxybenzoic acid 2-ethylhexylester, and polyethyleneglycol. However, among these, alcohols, ester phosphates, carboxilic acid esters, alkylated biphenyl, alkylated taphenyl, alkylated naphthalene, are diallylethane are preferable. Further, carbonization inhibitors such as hindered phenol, hindered amine, and the like can be added to the aforementioned high boiling point oils. Further, oil having unsaturated fatty acid such as xcex1-methylstylenedimer is particularly desirable. As xcex1-methylstylenedimer, MSD100 is available from Mitsui Toatsu Chemicals, Inc.
The aforementioned diazonium salt compound is a compound which is represented by the following equation, and forms a color through a coupling reaction with a coupler due to heating, and decomposes by light. The maximum absorption wavelength of such compound can be controlled in accordance with the position or type of a substituent group of Ar part.
Arxe2x88x92N2+Xxe2x88x92
(wherein Ar represents an aromatic part, and Xxe2x88x92 represents an acid anion.)
Specific examples of diazonium for forming salt include: 4-(p-tolylthio)-2,5-dibuthoxybenzenediazonium, 4-(4-chlorophenylthio)-2,5-dibutoxybenzenediazonium, 4-(N,N-dimethylamino) benzenediazonium, 4-(N,N-diethylamino)benzenediazonium, 4-(N,N-dipropylamino)benzenediazonium, 4-(N-methyl-N-benzylamino)benzenediazonium, 4-(N,N-dibenzylamino)benzenediazonium, 4-(N-ethyl-N-hydroxyethylamino)benzenediazonium, 4-(N,N-diethylamino)-3-methoxybenzenediazonium, 4-(N,N-dimethylamino)-2-methoxybenzenediazonium, 4-(N-benzoylamino) -2,5-diethoxybenzenidiazonium, 4-morpholino-2,5-dibuthoxybenzenediazonuim, 4-anilinobenzenediazonium, 4-[N-(4-methoxybenzoyl)amino]-2,5-diethoxybenzenediazonium, 4-pyrolidino-3-ethylbenzenediazonium, 4-[N-(1-methyl-2-(4-methoxyphenoxy)ethyl)-N-hexylamino]-2-hexyloxybenzenediazonium, 4-[N-(2-(4-methoxyphenoxy)ethyl)-N-hexylamino]-2-hexyloxybenzenediazonium, 2-(1-ethylpropyloxy) -4-[di-(di-n-buthylaminocarbonylmethyl) amino]benzenediazonium, 2-benzylsulfonyl-4-[N-methyl-N-(2-octanoyloxyethyl)]aminobenzenediazonium, and the like.
In the present invention, a coupler which is coupled with a diazo compound to form a dye can use any compound as long as it is coupled with a diazo compound and forms a dye in a basic atmosphere and/or a neutral atmosphere. All of the so-called 4-equivalent couplers for silver halide photographic light-sensitive materials can be used as the coupler. These couplers can be selected in accordance with the desired hue.
Examples of the couplers include: resorcinol, phloroglucin, 2,3-dihydroxynaphthalene, 2,3-dihydroxynaphthalene-6-sodium sulfonic acid, 1-hydroxy-2-naphthoic acid morpholino propyl amide, 2-hydroxy-3-naphthalenesulfonic acid sodium, 2-hydroxy-3-naphthalenesulfonic acid anilido, 2-hydroxy-3-naphthalenesulfonic acid morpholinopropylamide, 2-hydroxy-3-naphthalenesulfonic acid-2-ethylhexyloxypropylamide, 2-hydroxy-3-naphthalenesulfonic acid-2-ethylhexylamide, 5-acetoamide-1-naphthol, 1-hydroxy-8-acetoamidenaphthalene-3,6-disulfonic acid sodium, 1-hydroxy-8-acetoamidenaphthalene-3,6-disulphonic acid dianilide, 1,5-dihydroxynaphthalene, 2-hydroxy-3-naphthoic acid morpholinopropylamide, 2-hydroxy-3-naphthoic acid octyl amide, 2-hydroxy-3-naphtoic acid anilide, 5,5-dimethyl-1,3-cyclohexanedione, 1,3-cyclopentanedione, 5-(2-n-tetradecyloxyphenyl)-1,3-cyclohexanedione, 5-phenyl-4-methoxycarbonyl-1,3-cyclohexanedione, 5-(2,5-di-n-octyloxyphenyl)-1,3-cyclohexanedione, N,Nxe2x80x2-dicyclohexyl barbituric acid, N,Nxe2x80x2-di-n-dodecyl barbituric acid, N-n-octyl-Nxe2x80x2-n-octadecyl barbituric acid, N-phenyl-Nxe2x80x2-(2,5-di-n-octyloxyphenyl)barbituric acid, N-phenyl-Nxe2x80x2-bis(octadecyloxycarbonylmethyl) barbituric acid, 1-phenyl-3-methyl-5-pyrazolone, 1-(2,4,6-trichlorophenyl)-3-anilino-5-pyrazolone, 1-(2,4,6-trichlorophenyl)-3-benzamide-5-pyrazolone, 6-hydroxy-4-methyl-3-cyano-1-(2-ethylhexyl)-2-pyridone, 2,4-bis-(benzoylacetoamide)toluene, 1,3-bis-(pivaloylacetoamidemethyl)benzene, benzoylacetonitrile, thenoylacetonitrile, acetoacetoanilide, benzoylacetoanilide, pivaloylacetoanilide, 2-chloro-5-(N-n-butylsulphamoyl)-1-pivaloylacetoamidebenzene, 1-(2-ethylhexloxypropyl)-3-cyano-4-methyl-6-hydroxy-1,2-dihydropyridine-2-on, 1-(dodecyloxypropyl)-3-acetyl-4-methyl-6-hydroxy-1,2-dihydropyridine-2-on, 1-(4-n-octyloxyphenyl)-3-tert-butyl-5-aminopyrozol, and the like. Details of such couplers are disclosed in Japanese Patent Application Laid-Open (JP-A) Nos. 4-201483, 7-223367, 7-223368, 7-323660, 5-278608, 5-297024, 6-18669, 6-18670, 7-316280, 8-027095, 8-027096, 8-030799, 8-12610, 8-132394, 8-358755, 8-358756, and 9-069990.
Examples of the electron donating dye precursor encapsulated in the microcapsules of the present invention include: a triallyl methane compound, a diphenyl methane compound, a thiadine compound, a xanthene compound, and a spiropyran compound. Especially, the triallyl methane compound and the xanthene compound have high color-forming density and are useful. Examples of these compounds include: 3,3-bis(p-dimethylaminophenyl)-6-dimethylaminophthalide (i.e., crystal violet lantone), 3,3-bis(p-dimethylamino)phthalide, 3-(p-dimethylaminophenyl)-3-(1,3-dimethylindole-3-il)phthalide, 3-(p-dimethylaminophenyl)-3-(2-methylindole-3-il)phthalide, 3-(o-methyl-p-diethylaminophenyl)-3-(2-methylindole-3-il)phthalide, 4,4xe2x80x2-bis (dimethylamino)benzhydrinbenzylether, N-halophenylleukoauramine, N-2,4,5-trichlorophenylleukoauramine, rhodamine-B-anilinoklactam, rhodamine (p-nitroanilino)lactam, rhodamine-B-(p-chloroanilino)lactam, 2-benzylamino-6-diethylaminofluoran, 2-anilino-6-diethylaminofluoran, 2-anilino-3-methyl-6-diethylaminofluoran, 2-anilino-3-methyl-6-cyclohexylmethylaminofluoran, 2-anilino-3-methyl-6-isoamylethylaminofluoran, 2-(o-chloroanilino)-6-diethylaminofluoran, 2-octylamino-6-diethylaminofluoran, 2-ethoxyethylamino-3-chloro-2-diethylaminofluoran, 2-anilino-3-chloro-6-diethylaminofluoran, benzoylleukomethyleneblue, p-nitrobenzylleukomethyleneblue, 3-methyl-spiro-dinaphtopyran, 3-ethyl- spiro-dinaphtopyran, 3,3xe2x80x2-dichloro-spiro-dinaphtapyran, 3-benzylspirodinaphtopyran, 3-propyl-spiro-dibenzopyran, and the like.
Examples of the electron accepting compound include: phenol derivatives, salicylic acid derivatives, and hydroxy benzoic acid esters. The bisphenols, hydroxy benzoic acid esters, and the like are particularly preferable. Some examples of these include: 2,2-bis(p-hydroxyphenyl) propane (i.e., bisphenol A), 4,4xe2x80x2-(p-phenylenediisopropylidene)diphenol (i.e., bisphenol P), 2,2-bis(p-hydroxyphenyl)pentane, 2,2-bis(p-hydroxyphenyl)ethane, 2,2-bis (p-hydroxyphenyl)butane, 2,2-bis (4xe2x80x2-hydroxy-3xe2x80x2,5xe2x80x2-dychlorophenyl)propane, 1,1-(p-hydroxyphenyl)cyclohexane, 1,1-(p-hydroxyphenyl) propane, 1,1-(p-hydroxyphenyl)pentane, 1,1-(p-hydroxyphenhyl)-2-ethylhexane, 3,5-di(xcex1-methylbenzyl)salicylic acid and its polyvalent metallic salts, 3,5-di(tert-butyl)salicylic acid and its polyvalent metallic salts, 3-xcex1,xcex1-dimethylbenzyl salicylic acid and its polyvalent metallic salts, p-hydroxy benzoic acid butyl, p-hydroxy benzoic acid benzyl, p-hydroxy benzoic acid-2-ethylhexyl, p-phenylphenol, p-cumyl phenol, and the like.
As a sensitizer, low melting point organic compounds moderately containing aromatic groups and polar groups in molecules are preferable. Examples of the sensitizers include: p-benzyloxy benzoic acid benzyl, xcex1-naphthyl benzyl ether, xcex2-naphthyl benzyl ether, xcex2-naphthoic acid phenyl ester, xcex1-hydroxy-xcex2-naphthoic acid phenyl ester, xcex2-naphthol-(p-chlorobenzyl)ether, 1,4-butanediolphenylether, 1,4-butanediol-p-methylphenylether, 1,4-butanediol-p-ethylphenylether, 1,4-butanediol-m-methylphenylether, 1-phenoxy-2-(p-trioxy)ethane, 1-phenoxy-2-(p-ethylphenoxy)ethane, 1-phenoxy-2-(p-chlorophenoxy)ethane, p-benzylbiphenyl, and the like.
As a material for a microcapsule wall, high polymer substances are preferable. Specific examples of the high polymer substances include: polyurethane resin, polyurea resin, polyamide resin, polyester resin, polycarbonate resin, aminoaldehyde resin, melamine resin, polystyrene resin, styrene-acrylate copolymer resin, styrene-methacrylate copolymer resin, gelatin, polyvinyl alcohol, and the like. Among these, a particularly preferable wall agent is the polyurethane and/or polyurea resin.
Microcapsules having a wall film formed of the polyurethane and/or polyurea resin is produced by the steps of mixing a microcapsule wall precursor such as polyvalent isocyanate with a core substance to be micro-encapsulated, emulsifying the resultant mixture in an aqueous solution of a water-soluble high polymer compound such as polyvinyl alcohol, and raising the temperature of the obtained emulsion thus allowing a high polymer forming reaction to occur at the interface between oil drops.
Some specific examples of the polyvalent isocyanate compounds include: isocyanates such as m-phenylenediisocyanate, p-phenylenediisocyanate, 2,6-tolylenediisocyanate, 2,4-tolylenediisocyanate, naphthalene-1,4-diisocyanate, diphenylmethane-4,4xe2x80x2-diisocyanate, 3,3xe2x80x2-diphenylmethane-4,4xe2x80x2-diisocyanate, xylene-1,4-diisocyanate, 4,4xe2x80x2-diphenylpropanediisocyanate, trimethylenediisocyanate, hexamethylenediisocyanate, propylene-1,2-diisocyanate, butylene-1,2-diisocyaate, cyclohexylene-1,2-diisocyanate, and cyclohexylene-1,4-diisocyanate; triisocyanates such as 4,4xe2x80x2,4xe2x80x3-triphenylmethanetriisocyanate, and toluene-2,4,6-triisocyanate; tetraisocyanates such as 4,4xe2x80x2-dimethylphenylmethane-2,2xe2x80x2, and 5,5xe2x80x2-tetraisocyanate; and isocyanateprepolymers such as an adduct of hexanemethylenediisocyanate and trimethylolpropane, an adduct of 2,4-tolylenediisocyanate and trimethylolpropane, an adduct of xylenediisocyanate and trimethylolpropane, and an adduct of tolylenediisocyanate and hexanetriol. Further, two or more compounds can be used together as necessary. Among these, a compound having three or more isocyanate groups in a molecule is particularly preferable.
The coupler or the electron accepting compound which is contained in the heat-sensitive recording layer of the heat-sensitive recording material may be emulsified or solidly dispersed into particles. However, it is preferable that the coupler is preferably solidly dispersed.
The heat-sensitive recording material of the present invention can be produced by the steps of mixing the microcapsules dispersion thus prepared and the dispersion of the coupler or the electron accepting compound, coating this mixture on the support, and forming the heat-sensitive recording layer.

Method for producing microcapsules and heat-sensitive recording material


A semiconductor package includes a lead frame, a first chip, a second chip, a plurality of bonding wires and a mold compound. The lead frame includes a pad portion at a center of the frame and a plurality of lead portions. The pad portion and the plurality of lead portions collectively define a receiving portion. The first chip is securely received in the receiving portion. The second chip is mechanically attached to the first chip. The plurality of bonding wires electrically connect the second chip to the plurality of lead portions. The mold compound encapsulates the lead frame, the first chip, the second chip and the plurality of bonding wires to form the semiconductor package.

1. Technical Field
The present disclosure relates to a lead frame for use in packages for mounting semiconductor elements. More particularly, the present disclosure relates to a lead frame used in a quad flat non-leaded package (QFN), and to a semiconductor package using the lead frame.
2. Description of Related Art
A semiconductor package typically comprises a substrate, a first chip, and a second chip. The first chip is disposed on the substrate and the second chip is disposed on the first chip, that is, the first chip is sandwiched between the substrate and the second chip. However, the semiconductor chip package has a big volume so as not to meet the development of miniaturized electronic products.
Therefore, a need exists in the industry to overcome the described limitations.

Lead frame and semiconductor package using the same


A system is disclosed for removing fluids from a felt in a paper making process. The system includes a vacuum source for providing a vacuum adjacent a vacuum plate against the felt is moved, and crescent shaped openings in the vacuum plate through which the vacuum is applied to the felt for the removal of the fluids.

The invention generally relates to paper making systems and processes, and relates in particular, to systems and processes for facilitating the removal of fluids from papermaking material during paper making processes.
In the paper making process the press section is equipped with conveying belts commonly referred to as felts. The felts act to carry the newly formed, very wet paper to the pressing rolls where a considerable amount of water is forced out of the paper and into the felts. As these felts are serpentine in nature, it is necessary to remove the captured water from the felts so that the process of water removal from the paper is repeated as the continuous supply of newly form paper is processed through the press section.
The method presently in use today for water extraction from the serpentine felt involves the use of a vacuum element in the belt run commonly referred to as the fluid extraction box or Uhle box, which is typically constructed from a pipe or enclosure that has a contact wear surface attached to it. This contact wear surface incorporates within the design a through path for the vacuum applied water extraction stream to drain into. The vacuum applied to the felt is considerable and causes the felt to be pulled tightly onto the contact wear surface and into the vacuum port open area. This cover includes ports or pathways for the extracted water to be conveyed/evacuated to.
These vacuum application ports may be in various geometric configurations. Conventionally, the shape and open area of the port is sized for the vacuum exposure dwell time on the moving serpentine felt; dwell time that is too long wastes energy, too short does not allow enough time for the water to be fully extracted. Also, another design consideration is the slot (or opening) width, which has a direct correlation to felt wear and felt seam failure modes.
There remains a need however, for more efficient and effective systems for removing fluids from felts while minimizing wear on the felts.

Systems and methods for providing shaped vacuum ports for fluid extraction vacuum box covers in papermaking systems


A plastic spectacle lens includes a protuberance portion intergrally formed with a peripheral portion of one of the concave and convex sides thereof for indicating information thereof. Indication of the class and the power of the lens in the protuberance portion facilitates determination of specifications of the lens.

The present invention relates to a plastic spectacle lens for sight curing.
Before being machined for fitting to spectacle frames, plastic spectacle lenses are generally circular, and particular directions such as a principal meridian are not determined yet. According to specific operations, specification of directivity of each of lenses, such as the direction of the principal meridian, becomes necessary. In practice, the direction, such as direction of the principal meridian, of each lens must be specified in the following events: for example, determination of the power and the astigmatism axis of the lens; half coloring to color a half of the lens; and fitting of the lens to a spectacle frame in a correct direction.
In progressive power multi-focus lens, it is preferable to previously indicate information of the classification thereof on the lens surface. There may be a case where lenses of a specific characteristic are taken out from many lenses having different characteristics.
In spite of such needs, blanks of conventional plastic spectacle lenses have no indicia to indicate directional instructions, a class and a power. To determine the direction of a lens, an instrument, such as a lens meter, must be used. Alternatively, each lens is accompanied with an instruction slip indicating a directivity, a classification and a power thereof, and production of the lens must be done referring to the instruction slip. This deteriorates productivity of spectacles. Moreover in case of losing an instruction slip, it is hard to quickly know the information of the lens.

Plastic spectacle lens and method for making


There is provided a method of creating computer instructions for transforming inbound instances, being instances of a hierarchical inbound data format, into outbound instances, being instances of at least one hierarchical outbound data format, wherein each inbound instance is transformed into zero, one or more outbound instances, the inbound and outbound data formats each having a number of segments arranged in a hierarchical manner, the method using a computing device having at least a processor, a memory, a display device and an input device, and the method including:                retrieving from the memory and providing on the display device a number of operation icons each representing at least one operation to be performed on data; and        enabling a user of the computing device to select and arrange at least some of the operation icons on the display device.

The present specification describes features of a new product known as Microgen Aptitude V3.00. This product is a development of Microgen's earlier Aptitude product which is described in U.S. patent application Ser. No. 11/341,156 (publication no US-2006-0247805-A1) and corresponding European Patent Application No 06100913.0 (publication no 1,686,466), the contents of which are incorporated herein by reference.
Aptitude is a program with a graphical interface which allows users to create complex applications without knowledge of traditional programming languages.

Transformation of hierarchical data formats using graphical rules


A semiconductor device comprising a substrate, a power bus, a heat source circuit, a heat sensitive circuit, and a plurality of electrically and thermally conductive through-silicon-vias (TSVs) in the substrate. The TSVs are electrically coupled to the power bus and positioned between the heat source circuit and the heat sensitive circuit to absorb heat from the heat source circuit.

1. Field
This disclosure relates generally to semiconductor devices, and more specifically, to reducing heat exposure of thermally sensitive semiconductor devices.
2. Related Art
Thermally sensitive semiconductor components may be sensitive to heat transferred from neighboring components on a die even if the devices do not generate much heat themselves. For example, transistors in a Double Data Rate type 3 (DDR3) Random Access Memory (RAM) memory die may be sensitive to heat from neighboring sense amps, write, and pre-charge circuits. As the temperature of the transistors increases, the transistors leak current and the refresh rate of the transistors must be increased to prevent the transistors from losing the data being stored. Increased refresh rates use more power than lower refresh rates. As semiconductor die are designed with ever increasing functionality and speed requirements, it is desirable to find ways to reduce power consumption as well as reduce/remove heat generated by the die.

Methods and structures for reducing heat exposure of thermally sensitive semiconductor devices


A semiconductor storage device includes an interlayer insulating film provided between select gate electrodes, a first fill material extending along upper portions of memory cell gate electrodes so as to cover air gaps residing between the memory cell gate electrodes, the first fill material extending along sidewalls of the select gate electrodes and sidewalls of the interlayer insulating film so as to define a recess above the first fill material extending along the sidewalls of the select gate electrodes and the sidewalls of the interlayer insulating film, a second fill material filling the recess above the first fill material, and a plurality of contacts formed through the interlayer insulating film, the contacts physically contacting each of device areas formed in a semiconductor substrate.

Semiconductor storage device such as a NAND flash memory device is facing increasing demand for further microfabrication. Narrower memory cell requires smaller spacing between the neighboring memory cell gate electrodes and thereby increases cross coupling effect of the memory cell gate electrodes to an unignorable level. Cross coupling effect is typically observed through a shift in the threshold voltage of a programmed memory cell transistor by the influence of the subsequent programming of adjacent memory cell transistors. Cross coupling effect expands the range of threshold voltage distribution and thus, may lead to erroneous data read out.
Increased capacitive coupling between adjacent memory cell gate electrodes originating from narrowed memory cell gate electrode gaps increases the magnitude of cross coupling effect. On solution may be forming air gaps between the memory cell gate electrodes to reduce the capacitive coupling between the adjacent memory cell gate electrodes.
Formation of air gaps between the adjacent memory cell gate electrodes also forms air gaps between select gate electrodes and contacts. Such configuration risks the possibility of contact shorting by errors such as etching errors and misalignment. More specifically, when the contact hole is unwantedly connected with the air gap formed in the proximity of the select gate electrode, the contact material may be introduced into the air gap to cause shorting of the adjacent contacts, which in turn leads to yield degradation of the memory being manufactured.

Semiconductor storage device including a memory cell structure


A selector pen for touch screen includes a barrel having a light emitter mounted therein to be turned on or off through turning of a switch rotatably connected to a rear end of the barrel. The switch includes a base defining a non-circular insertion hole, a movable rod being fixedly received in the insertion hole of the movable rod and having an inclined top formed into a spiral guide surface, and a cap being rotatably covered onto the base and having an internal projection. When the cap is turned, the projection slides along the spiral guide surface to gradually depress the movable rod for the same to electrically make the light emitter. The switch has simplified structure and the spiral guide surface defines a definite range of turning for the cap.

The present invention relates to a selector pen, and more particularly to a selector pen for touch screen that has a structurally simplified switch and could be manufactured at lowered cost.
With the highly advanced computer technology, various kinds of electronic products have been developed to have compact volume and increased functions. For example, there are many applied electronic products having key-controlled functions directly provided on a screen thereof. The screen is provided with a sensing membrane via which user""s instructions are entered. Such screen is referred to as a touch screen and was originally developed for big-size screens for general computers but has currently been employed on small-size liquid crystal display (LCD) for electronic dictionary, personal digital assistant (PDA), etc. To enter instructions or to select options on the touch screen, a selector pen (that is, a light pen) is usually needed to touch the screen, though the instructions and the selections may also be entered by handwriting.
FIG. 1 is an exploded perspective view of a conventional selector pen 10. As shown, the selector pen 10 mainly includes a barrel 1, a transparent head 2, a light-emitting means 3, and a switch 4.
The barrel 1 is a hollow tube with the transparent head 2 fixedly connected to a front end thereof and the light-emitting means 3 mounted therein. A rear end of the barrel 1 is provided with an internal screw thread 11 for the switch 4 to screw thereinto.
The transparent head 2 is a substantially conic body having a blunt front point 21 and allows light emitted from the light-emitting means 3 inside the barrel 1 to pass therethrough.
The light-emitting means 3 includes a circuit board 31 having a light emitter 32, which is preferably a light emitting diode, connected thereto; a big spring 33 connected to a positive electrode of a power input of the circuit board 31; a small spring 34 connected to a negative electrode and located at a center in the big spring 33; and a battery 35 having a front outer peripheral surface forming a positive electrode to contact with the big spring 33 and a bar-shaped negative electrode forward projected from a center of the positive electrode to extend into the big spring 33 for contacting with the small spring 34. When a special light emitting diode is used, such as a white light emitting diode that needs a voltage higher than that for general light emitting diodes, the circuit board 31 is additionally provided with a voltage booster circuit 36, so that the voltage rises from low to high voltage to provide the special light emitting diode with normal working voltage.
The switch 4 includes a fixing seat 41, a movable rod 42, and a cap 43. The fixing seat 41 is a hollow tube generally divided into a lower half and an upper half. An upper outer periphery of the lower half is provided with a collar 411 having an outer diameter corresponding to that of the barrel 1, and a lower outer periphery of the lower half below the collar 411 is provided with an external screw thread 412 for engaging with the internal screw thread 11 of the barrel 1. The upper half of the fixing seat 41 is provided at an inner upper end with an internal screw thread 413. The movable rod 42 is provided around a lower portion of an upper half with an external screw thread 421 corresponding to the internal screw thread 413 of the fixing seat 41, immediately above the external screw thread 421 with a diameter-reduced gear 422, and above the gear 422 with a shaft 423. The cap 43 has an open lower end communicable with a stepped internal space defined by the cap 43. The stepped internal space of the cap 43 includes a first recess 431 most close to the open lower end for receiving the fixing seat 41 and the movable rod 42, a second recess behind the first recess for receiving the gear 432, and a third recess behind the second recess for receiving the shaft 433. The movable rod 42 is rotatably, upward and downward movably mounted in the fixing seat 41 through engagement of the external screw thread 421 with the internal screw thread 413.
When the light-emitting means 3 is mounted in the barrel 1, the light emitter 32 is caused to face forward and contact with the transparent head 2, and the big and the small springs 33, 34 are located behind the light emitter 32 to correspond to the positive and the negative electrodes, respectively, of the battery 35. Due to a spring force applied by the big spring 33 on the battery 35 to push the latter backward, the small spring 34 is normally prevented from electrically contacting with the bar-shaped negative electrode of the battery 35. And, the switch 4 is connected to the barrel 1 by screwing the fixing seat 41 to the rear end of the barrel 1 with a front-end surface of the movable rod 42 normally pressed against a rear-end surface of the battery 35. FIG. 2 is a sectional view of the assembled selector pen 10, wherein the light-emitting means 3 is not electrically made to emit light.
For the selector pen 10 to emit light, simply turn the cap 43 in a predetermined direction, so that the gear 422 received in the second recess 432 of the cap 43 is brought to rotate. At this point, the external screw thread 421 of the movable rod 42 is guided by the internal screw thread 413 of the fixing seat 41 to move forward, bringing the movable rod 42 to push against the battery 35 and accordingly compress the big spring 33. At this point, the bar-shaped negative electrode of the battery 35 is gradually moved forward to eventually contact the small spring 34 to make the light emitter 32 for the latter to emit light, as shown in FIG. 3. When the cap 43 is turned reversely, the movable rod 42 is brought to move backward and the light emitter 32 is turned off, accordingly, as shown in FIG. 2.
The above-described conventional selector pen 10 has the following disadvantages in its structure and operation:
1. The cap 43 includes a stepped internal space providing three recesses of different inner diameters. The middle one of the three recesses is configured to receive the gear 422, making it difficult and time-consuming to manufacture components for the switch 4.
2. Due to the switch 4 that is difficult and time-consuming to manufacture, the selector pen 10 is produced at increased cost.
3. When the cap 43 is turned clockwise or counterclockwise relative to the barrel 1 to turn on or off the light-emitting means 3, the internal and the external screw threads 413 and 421, due to their very delicate structure and therefore insufficient supporting pressure, tend to slip relative to one another, causing the switch 4 to lose its intended control function.
4. The switch 4 is not designed with means for actually defining exact number of turns of the switch 4 in order to turn on or off the light-emitting means 3. When the cap 43 is overly turned, for example, when the battery 35 is exhausted, the screw threads 413 and 421 tend to slip relative to one another or even break.
It is therefore tried by the inventor to develop a selector pen that has improved but simplified switch structure to eliminate the above-mentioned disadvantages existing in the conventional selector pen.
A primary object of the present invention is to provide a selector pen for touch screen, on which a simplified switch is provided to turn on or off a light-emitting means mounted in a barrel of the selector pen, so that the selector pen could be manufactured at lowered cost and effectively emit light when necessary.
To achieve the above and other objects, the selector pen for touch screen of the present invention mainly includes a barrel, a transparent head connected to a front end of the barrel, a light-emitting means mounted in the barrel to emit light that passes through the transparent head to illuminate a dim environment near the touch screen, and a switch rotatably connected to a rear end of the barrel to turn on or off the light-emitting means. The switch includes a base defining a non-circular insertion hole, a movable rod being fixedly received in the insertion hole of the movable rod and having an inclined top formed into a spiral guide surface, and a cap being rotatably covered onto the base and having an internal projection. When the cap is turned, the projection slides along the spiral guide surface to gradually depress the movable rod for the same to electrically make the light-emitting means.
The switch has simplified structure to enable lowered manufacturing cost of the selector pen, and the spiral guide surface defines a definite range of turning for the cap to avoid the problem of insufficiently or overly turned switch.