Electrophotographic developer compositions containing carrier, toner and special purpose additives such as flow promoters, dry lubricants and the like are prepared by coating carrier particles with a coating selected so that the triboelectric relationship between the surface of the carrier and the surface of the additive is substantially zero.

In electrophotography, a photoconductor is charged and then exposed imagewise to light. In the area of the photoconductor which is exposed to light, the charge selectively leaks, while the dark areas retain the electrostatic charge in the form of a latent electrostatic image. The latent image is then developed by deposition of finely divided electroscopic material known as toner. The thus produced toner image may then be fixed to the photoconductive surface to produce a permanent visible image. Alternatively, the toner image may be transferred from the photoconductive surface to another support surface such as paper and then permanently fixed to the new support, for example, by heat.
A number of methods are available for developing the latent electrostatic image by deposition of toner. One is the cascade method which is described in U.S. Pat. No. 2,618,552 to Wise. Another is known as the magnetic brush process and is described in U.S. Pat. No. 2,874,063 to Greig.
In each of these methods, a developer comprising relatively large carrier particles together with a low proportion by weight of smaller toner particles is brought into contact with the latent image. The toner particles are held to the surface of the carrier particles by electrostatic forces which develop from the contact between the toner and carrier particles producing triboelectric charging of the toner and the carrier to opposite polarities. The toner particles are removed from the carrier when in contact with the latent electrostatic image by the stronger electrostatic attraction between the image and the toner.
Both systems include recycling of the developer and, obviously, continuing removal of toner from the initial developer supply as the toner is utilized to form images. The toner, therefore, must be replenished from time to time by the addition of fresh toner.
While the principal components of the developer are the carrier and the toner, it is customary to add special purpose additives, for example flow promoters, dry lubricants, and the like, in order to improve the developer. U.S. Pat. No. 3,720,617, for example, describes the addition of submicroscopic silicon dioxide particles to overcome various deficiencies of ordinary two component developers. This additive appears to assist in maintaining the stability of the electrical properties of toner and carrier when the developer is subjected to variation in humidity. The additive also assists in retarding deposition of films of toner material on reusable photoreceptor surfaces.
It is also known to add various lubricants such as zinc stearate or fluorohydrocarbon polymers such as polytetrafluoroethylene to the developer to enhance its flow properties.
The use of the additives, while they perform their special functions well, gives rise to a new problem. This is the problem of maintaining the concentration of the various components in the developer at a reasonably constant level as toner is continuously utilized to produce images and replenished from time to time.
The production of a large number of high quality images requires the delicate balance of many optical, mechanical and electrostatic properties. Amongst these, one of the most important is the triboelectric relationships between the components in the developer. If these relationships are continually changing with the production of images, the quality of the images will vary as more or less toner is deposited on successive latent electrostatic images.
The presence of a special purpose additive often gives rise to variations in the triboelectric relationship between the toner, the carrier and the additive since the additive may deposit on the carrier, or on the photoconductors, or it may be deposited with the toner as part of the image. In the last event, it exits the system. In the first two instances, the additive is subject to continuous recirculation. At any particular point in time, a specific sample of the additive may be on the carrier, on the photoreceptor or in the developer. The abrasive action of the moving components in the developer may thereafter remove the additive from the carrier or the photoreceptor so that the concentration of the additive in the developer is constantly changing. This perpetual fluctuation of concentration is not corrected when the toner supply is replenished since the replenishing charge normally has a fixed concentration of toner and additive. The end result is a continuously fluctuating triboelectric relationship between the toner and the carrier.
This fluctuation is readily observed by the variations in quality of the images produced. It may be quantitatively determined by measuring the charge to mass ratio of the developer. If this is continuously changing, the concentration of the components in the developer and the tribo relationships between the components of the developer must also be changing.
For convenience, this invention will be described principally as it relates to the lubricant, zinc stearate, as a minor component in a developer. Zinc stearate, which is normally employed as a finely divided powder, is a soft, non-abrasive material which when used in a developer as a flow promotor or a flow lubricant, tends to coat the carrier and to abrade from the carrier. As a result, the tribo relationship between the carrier and the toner is constantly changing. If it were possible to coat the carrier completely with zinc stearate, the characteristics would remain constant. As a practical matter, this is not possible since the abrasive action of the constantly moving developer continuously removes the zinc stearate.
In a typical developer, the toner is more strongly attracted by electrical charges to the carrier than the stearate is attracted to the carrier, and the stearate is weakly attracted to the toner by electric charges. At the same time, the stearate, because of its relative softness and flowability, tends to deposit on the carrier. As a result of the electrical attraction of the toner for the stearate, a relatively large amount of stearate is removed with the toner, but the amount changes constantly due to the varying tribo characteristics of the system resulting from the deposition and removal of zinc stearate from the surface of the carrier.
It has now been discovered that in an electrophotographic developer composition containing a minor amount of a special purpose additive, the concentration of the additive with respect to the toner and the carrier can be maintained essentially constant if the surface triboelectric relationship of the carrier and the additive is maintained substantially zero, i.e. there is substantially no difference. For example, in a developer comprising toner particles, zinc stearate and carrier particles, if the triboelectric difference between the surface of the carrier particles and the surface of the zinc stearate is zero, or close thereto the tribo relationship between the carrier and the toner will remain substantially constant. As a result, the amount of zinc stearate which exits the system with the toner remains substantially constant, and the relative concentrations of the toner-additive-carrier components in the developer can be maintained substantially constant by replenishing the toner and additive with a mixture containing fixed amounts of toner particles and zinc stearate. The fact that the system remains stable is visually evident by the uniformly constant quality of the reproductions even when as many as 80,000 or more copies are produced while the toner is continuously replenished to maintain a constant toner concentration while utilizing a total of 2 kg of developer. It can also be determined quantitatively by measuring the concentration of the components or by determining the charge to mass ratio, for example, in a Faraday box as described by Harpavat and Orr in the IAS '75 Annual, pages 158 to 164, or in U.S. Pat. No. 4,053,310 to Lee.
In the optimum practice of this invention, the triboelectric charge of the additive relative to the carrier is zero so that there is no bonding force holding the additive to the carrier. At the same time, there is a bonding force between the toner and the additive, so that the toner and the additive are held together. Ideally, the additive deposits on the latent electrostatic image with the toner in the same ratio as was present initially and is present in each successive replenishing charge. The amount of additive present in a developer is always very low. Only rarely will it be higher than 2% by weight based on the weight of the toner present. Typically, it will be 0.05% to 1.5%. Usually the amount of toner is at least fifty times the weight of the additive.
As is known, carrier particles normally comprise a core material and a coating. The diameter of the core material is generally from 50 to 1000 microns, preferably 100 to 600 microns. Any of a wide variety of materials may be used as the core. For use with the magnetic brush, the core should be a ferromagnetic material such as iron, steel, ferrite, etc. These same materials can be used with non-magnetic cores as can sand, glass beads or other known materials.
It is customary to coat the carrier core so as to improve the physical and chemical properties of the carrier particles. Typical coatings which have been used include cellulose acetate butyrate polymers, fluorocarbon polymers and the like.
U.S. Pat. Nos. 3,533,835 and 3,752,666 describe developer compositions in which the carrier is coated with lacquer. U.S. Pat. Nos. 3,526,533 and 3,627,522 to Jacknow et al. describe developers in which the carrier is coated with a mixture of styrene, acrylic polymers and organosilicones. Other coating materials and processes are described in U.S. Pat. Nos. 3,798,167, 3,947,271 and 4,053,310. However no completely satisfactory coating has yet been described. The prior art coatings are deficient for any of several reasons including, for example, difficulty in applying the coating; expense of the coating; carrier filming in which the carrier is gradually impacted by toner particles; requirement for extensive curing at high temperatures; tendency to chip, flake or peal; or failure to produce a sufficient number of acceptable copies per given quantity of developer.
The novel carrier coatings presently preferred for use in this invention substantially alleviate many of the above mentioned difficulties. They are miscible mixtures of butadiene-acrylonitrile rubber containing from about 20% to 40% acrylonitrile together with a polyurethane elastomer. Coatings produced with these mixtures are tough, tenacious and non-tacky. They do not abrade away from the core nor do the thus coated carrier particles tend to adhere to the additives, the toner or the other surfaces with which they come in contact, including the photoreceptor surface. They are easily applied by solvent coating, do not require pretreatment of the carrier or a high temperature curing cycle.
The presently preferred butadiene-acrylonitrile rubbers contain from about 20% to 40% acrylonitrile. Typically useful rubbers include those having a specific gravity of from 0.95 to 1.00 and an average Mooney viscosity of from 30 to 80. Such rubbers are available commercially under the trademark Hycar from B. F. Goodrich. They are soluble in organic solvents especially polar organic solvents such as methyl ethyl ketone, acetone, tetrahydrofuran and dimethyl formamide.
The following table gives the code number and some of the characteristics of those Hycar rubbers which are useful in this invention.
______________________________________ AVERAGE SPECIFIC MOONEY TYPE % ACRYLONITRILE GRAVITY VISCOSITY ______________________________________ 1031 41 1.00 60 1042 33 0.98 80 1042F 33 0.98 80 1094-80 21 0.95 80 1432 33 0.98 80 ______________________________________
Hycar 1432 which is dusted with a ketone soluble polyvinyl chloride resin is the present rubber of choice because of the excellent results obtained through its use.
The polyurethanes useful in this invention are thermoplastic elastomers which are the reaction products of polyesters or polyethers and diisocyanates. They are film forming resins and are soluble in organic solvents such as those mentioned above. They are prepared by the reaction of linear hydroxy terminated polyesters, usually adipates; or polyethers, usually poly(oxytetramethylene) glycol with glycols such as ethylene glycol and 1,4-butanediol and diisocyanates, most commonly diphenylmethane-4,4'-diisocyanate.
The presently preferred elastomers are available from B. F. Goodrich under the trademark Estane. They are believed to be the reaction products of adipic acid, 1,4-butanediol and diphenylmethane-4,4'-diisocyanate. The presently preferred estane is sold as Estane 5715. It is preferred because it is readily soluble in methyl ethyl ketone, a common, inexpensive solvent which also dissolves the Hycar rubbers, and because it can be formed into an extremely hard, flexible film with excellent abrasion resistance. Its physical properties are shown below:
______________________________________ TYPICAL VALUE ASTM TEST PHYSICAL PROPERTIES (1) PROCEDURE ______________________________________ Specific Gravity 1.20 D-792 Hardness, Durometer A 97 D-2240 (2) Durometer D 63 Tensile Strength (psi) 6150 D-882 (3) Modulus @ 100% Elongation (psi) 1400 Elongation (%) 300 Graves Tear (lbs/in) 260 D-1004 Tear Propagation (lbs/in) 120 Solution Viscosity (20% TS 100-200 (4) Concentration in MEK, Brookfield RVF Viscometer No. 2 Spindle, 20 rmp, 25.degree. C., cps. ______________________________________ (1) Representative solution cast film data on typical production material (2) Test conducted on 75 mil tensile sheets. (3) Test conducted on dumbbell film samples. (4) Actual specification value.
The butadiene-acrylonitrile rubbers used in the practice of this invention possess extremely high positive triboelectric characteristics. Carrier coatings prepared from a solution of Hycar 1432 exhibit a triboelectric charge of over 60 microcoulombs per gram of toner in a developer mixture containing two parts of toner for every 98 parts of coated carrier beads. The polyurethanes, on the other hand, have relatively low to moderate positive triboelectric characteristics. For Estane 5715 the comparable charge is 15 microcoulombs. It has been found that the two polymers can be mixed in varying proportions and coated on core materials to produce carrier particles with selected triboelectric characteristics. The carrier particles when mixed with toner will manifest triboelectric characteristics intermediate the high of the butadiene-acrylonitrile rubber and the low of the polyurethane elastomer.
The selected coating may be applied to the core by any suitable means to produce carrier particles which can be used with a wide variety of toner particles in accordance with the process of the invention. For example, the coating may be applied by dipping, spraying or tumbling the cores with a coating solution in a barrel or through a fluidized bed. The fluidized bed process is preferred since it permits the production of a uniform coating on the core particles. The process is described in U.S. Pat. Nos. 2,648,409, 2,799,241 and 3,253,944 to Wurster and 3,196,827 and 3,241,520 to Wurster et al.
In the Wurster fluidized bed process, for example, the cores are suspended and circulated in an upwardly flowing stream of heated gas such as air in a manner such that the particles move upwardly and are sprayed by the coating material in a first zone. Then, in a second zone, the particles settle through the air stream in a zone of lower air velocity and the liquid, which is a solvent and/or a dispersant of the sprayed coating evaporates to leave a thin solid coating on the particles. The particles recirculate to the first zone so that successive layers of the coating material are built up on the core in a uniform manner.
After the core has been coated to form the carrier particle, the coating is cured so as to possess the desired triboelectric properties. The curing process depends upon the material of the coating and the composition of the toner with which the carrier particles of the present invention are to be employed.
In this manner, novel coated carrier particles typically coated with from 0.25 to 2 g/Kg of carrier are prepared from organic solvent solutions containing a mixture comprising from 10% to 90% of the above described acrylonitrile-butadiene rubbers and 90% to 10% of the above described polyurethane elastomers based on the weight of the mixture. The core materials employed to produce the novel carrier particles include, for example, glass beads, steel shot and ferrite beads with diameters of from about 30 to 1000 microns. The thickness of the coatings may vary from about 1 to 20 microns, and is preferably 2 to 5 microns. Coatings prepared from mixtures containing 20% Hycar 1042 or 1432 together with 80% Estane 5715 are especially useful since the triboelectric relationship between the surface of these coated carriers and zinc stearate is close to zero.
The concept of this invention, that is the concept of establishing and maintaining the triboelectric relationship between the surface of the carrier particles and the surface of a minor additive substantially equal, thereby to control the relative concentration of electrophotographic developer components, is applicable to a variety of additives, carrier coatings and carrier cores. It is also applicable to a wide variety of toner particles. Typically, the toner particles are employed at a concentration of from about 5 to 75 g/Kg of coated carrier particles, or at a concentration of from about 0.05 to 7.5% by weight based on the weight of the carrier particles. Appreciable variation from these ranges can be tolerated, however, with different toner-additive-carrier combinations. The ranges are especially useful with dry electrophotographic developers employing zinc stearate or polytetrafluoroethylene as a lubricant.
Typical toner materials include polystyrene resin, acrylic resin, polyethylene resin, polyvinyl chloride resin, polyacrylamide resin, methacrylate resin, polyethylene terephthalate resin, polyamide resin, resinous condensation product of 2,2 bis-(4-hydroxyisopropoxy-phenyl)-propane and fumaric acid and copolymers, polyblends and mixtures thereof. Vinyl resins having a melting point or melting range starting at least about 100.degree. F. are especially suitable for use in the toners of this invention. These vinyl resins may be a homopolymer or a copolymer of two or more vinyl monomers. Typical monomeric units which may be employed to form vinyl polymers include styrene, vinyl naphthalene, mono-olefins such as ethylene, propylene, butylene, isobutylene and the like, vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate, vinyl butyrate and the like, esters of alphamethylene aliphatic monocarboxylic acids such as methyl acrylate, ethyl acrylate, n-butylacrylate, isobutyl acrylate, dodecyl acrylate, n-octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate and the like, vinyl ethers such as vinyl methyl ether, vinyl isobutyl ether, vinyl ethyl ether, and the like, vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, methyl isopropenyl ketone and the like, and mixtures thereof. Generally, suitable vinyl resins employed in the toner have a weight average molecular weight between about 3,000 to 500,000.
Toner resins containing a relatively high percentage of styrene resin are especially useful because a greater degree of image definition is achieved with a given quantity of additive material. Further, denser images are obtained when at least about 25% by weight based on the total weight of resin in the toner, of a styrene resin is present in the toner. The styrene resin may be a homopolymer of styrene or styrene homologues or copolymers of styrene with other monomeric groups containing a single methylene group attached to a carbon atom by a double bond. Thus, typical monomeric materials which may be copolymerized with styrene by addition polymerization include: vinyl naphthalene; mono-olefins such as ethylene, propylene, butylene, isobutylene and the like; vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate, vinyl butyrate and the like; esters of alpha-methylene aliphatic monocarboxylic acids such as methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, n-octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate and the like; vinyl ethers such as vinyl methyl ether, vinyl isobutyl ether, vinyl ethyl ether, and the like; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, methyl isopropenyl ketones and the like; and mixtures thereof. The styrene resins may also be formed by the polymerization of mixtures of two or more of the unsaturated monomeric materials with a styrene monomer.
The vinyl resins, including styrene type resins, may also be blended with one or more other resins if desired. When the vinyl resin is blended with another resin, the added resin is preferably another vinyl resin because the resulting blend is characterized by especially good triboelectric stability and uniform resistance against physical degradation. The vinyl resins employed for blending with the styrene type or other vinyl resin may be prepared by the addition polymerization of any suitable vinyl monomer such as the vinyl monomers described above. Other thermoplastic resins may also be blended with the vinyl resins of this invention. Typical non-vinyl type thermoplastic resins include: resin modified phenol formaldehyde resins, oil modified epoxy resins, polyurethane resins, cellulosic resins, polyether resins, polycarbonate resins and mixtures thereof. As indicated above, if the resin component of the toner contains styrene copolymerized with another unsaturated monomer or is a blend of polystyrene and other resins, a styrene component of at least about 25% by weight, based on the total weight of the resin present in the toner is preferred because denser images are obtained and a greater degree of image definition is achieved with a given quantity of additive material.
Typically, the size of the toner particles will be from about 1 to 20 microns.
The correct coating for use with a specific special purpose additive can be determined by a few simple tests using selected toner-additive combinations with a number of different coatings. In this procedure, fixed toner-additive mixtures are employed with various coated carriers to produce a number of electrophotographic copies, say 10,000. The quality of the prints is observed, the charge to mass ratio is measured and the concentration of toner is measured. If the copy quality remains uniform and the other values remain substantially constant, it follows that the triboelectric relationship between the coated carrier particles and the additive is zero or close to zero.
An alternative procedure can be used when the additive is capable of coating the carrier. In this procedure, the carrier is coated with the additive and the triboelectric relationship with respect to toner is observed. Separate samples of the carrier are then coated with selected coating materials and the triboelectric relationship with respect to the same toner is observed. If these latter observed relationships are approximately the same as the observed relationship when the carrier is coated with additive, the coating material will have substantially the same triboelectric relationship as the additive with respect to the same toner.
The second system described above works very well if zinc stearate is used as a lubricant additive. Since zinc stearate is relatively soft and flowable, it can be used to coat the carrier core. The triboelectric relationship between the thus coated carrier cores and the selected toner is observed. The carrier core is then coated with a number of different rubber-polyurethane elastomer combinations and the necessary measurements effected to determine the correct rubber-polyurethane combination. With Hycar 1042 or 1432 and Estane 5715, the optimum combination comprises 20% Hycar and 80% Estane by weight based on the weight of the mixture.
A third, and very convenient procedure is to measure the charge to mass ratio of the toner-carrier combination and the toner-carrier-additive combination. When these ratios are substantially the same, the additive has substantially the same triboelectric characteristic as the carrier.

Developer compositions with toner, coated carrier and lubricant


A method and apparatus for photoplethysmographic measurements is disclosed. In this system light from a plurality of emitters is delivered to the tissue-under-test. A subset of one or more of the emitters is known to be quiet light sources with relatively stable output intensity levels and spectral contents. A second subset of one or more emitters is known to be relatively noisy light sources with output intensity levels that fluctuate over time. The use of noisy light sources may be necessary for the photoplethysmographic measurements due to favorable spectral output characteristics such as narrow spectral bandwidth or desirable center wavelengths for the measurement of the hemodynamic parameters or analytes of interest. This invention utilizes the quiet light sources to enable the use of noisy light sources without the loss in accuracy or precision of analyte measurement that would otherwise typically be associated with the use of noisy light sources in the design and use of a photoplethysmographic instrument.

The present invention relates in general to a method and apparatus for eliminating the effects of noise inherent in certain optical sources used in photoplethysmographic measurements.
In the science of photoplethysmography, light is used to illuminate or trans-illuminate living tissue for the purpose of measuring blood analytes or other hemodynamic or tissue properties. In this monitoring modality light is injected into living tissue and a portion of the light which is not absorbed by the tissues, or scattered in some other direction, is detected a short distance from the entry point. The detected light is converted into an electronic signal that is indicative of the received light signal from the tissue. This electronic signal is then used to calculate physiologic parameters such as arterial blood oxygen saturation and hemodynamic variables such as heart rate, cardiac output, or tissue perfusion. Among the blood analytes that may be measured by photoplethysmography are the various species of hemoglobin, including the percentages of oxyhemoglobin, carboxyhemoglobin, methemoglobin, and reduced hemoglobin in the arterial blood. A device which detects and processes photoplethysmographic signals to measure the levels of various blood analytes and hemodynamic parameters is referred to as a photoplethysmographic apparatus, device, or instrument. Typically these instruments also include, and control, the light sources or emitters used to generate the light that illuminates the tissue.
The first widespread commercial use of photoplethysmography in medicine was in the pulse oximeter, a device designed to measure arterial blood oxygen saturation. To make these measurements, two different bands of light must be used, with each light band possessing a unique spectral content. Each spectral band, or light band, is typically referred to by the center wavelength, or sometimes by the peak wavelength, of the given band. In pulse oximetry two different light emitting diodes (LEDs) are typically used to generate the sensing light, one with a center, or peak, wavelength near 660 nanometers (nm) and a second with a center, or peak, wavelength near 940 nm.
Light from each LED light source, or emitter, is passed into the tissue-under-test, usually a finger, earlobe, or other relatively thin, well-perfused tissue sample. After passing some distance through the tissue-under-test, a portion of the light not absorbed by the tissue or scattered in some other direction is collected by a photodetector and converted into electronic signals that are directly proportional to the received light signals. The channels, or electronic signals from each of the different light sources, are kept separated through the use of any one of a number of different well-published techniques, including but not limited to, time-division multiplexing or frequency-division multiplexing.
The signals received from the tissue are referred to as photoplethysmographic signals. These signals consist of a small pulsatile component and a rather large constant component that changes slowly over time when compared with the pulsatile component of the signal. The pulsatile component of the photoplethysmographic signal is created by the pulsation of the blood in the tissue-under-test. When the heart contracts, it pushes blood out of the heart and into the peripheral tissues. This increases the optical density of the tissue located between the emitter and detector elements of the sensor, which decreases the amplitude of the received optical signals. As the heart relaxes and refills with blood, the optical density of the tissue-under-test decreases, and the received signal amplitude increases. The comparatively constant component of the photoplethysmographic signal is often referred to as the DC component of the signal, and the pulsatile component of the photoplethysmographic signal is often referred to as the AC component of the signal.
The photoplethysmographic signals are processed to obtain a measurement of the oxygen saturation in the arterial blood. This can be done in a number of different ways but all require mathematically relating the amplitude of the photoplethysmographic signals from each of the two channels to the arterial oxygen saturation.
In conventional pulse oximetry the instrument has only two channels, one associated with each emitter or light source used. With only two channels, only two blood analytes can be measured. Conventional pulse oximetry makes the mathematical assumption that there are primarily only two types of blood analytes in the arterial blood, oxyhemoglobin and reduced hemoglobin.
In order to measure only the arterial oxygen saturation, the pulse oximeter makes use of both the pulsatile component and the DC component of the photoplethysmographic signals. Because any pulsation of the venous system or capillaries is small by comparison to the arterial pulsation, changes in the amplitude of the photoplethysmographic signals will be dominated by the arterial pulsation. Note that the photoplethysmographic signals can be severely distorted by artifacts such as patient motion or electrocautery but elimination of these sources of artifacts is not the focus of this patent and will not be specifically addressed herein.
The amplitude of the pulsatile component of these photoplethysmographic signals can be extremely small. It is not uncommon for the percent modulation, or the peak-to-peak amplitude of the pulsatile portion divided by the constant portion, to be less than one part in one thousand, or 0.1%. Thus it is crucial that extremely quiet light sources are used to generate the signals for probing the tissue-under-test. This is necessary because any intensity noise in the light source that is within the frequency range of the passband of the photoplethysmographic device, or which can alias into its passband, will show up in the received photoplethysmographic signals and corrupt the desired measurements. Thus to allow for accurate and precise photoplethysmographic measurements, the light sources should be extremely quiet (also referred to as xe2x80x9cnoise freexe2x80x9d) or a means must be found to eliminate the light noise from the received signals.
Since the inception of photoplethysmography, this monitoring modality has been used to detect more and more different parameters. For example, a device was disclosed in Jarman et al U.S. Pat. No. 5,983,122 that is capable of measuring the percentages of four different analytes in the arterial blood, including oxyhemoglobin, carboxyhemoglobin, methemoglobin, and reduced hemoglobin.
As the number of different parameters measured by photoplethysmography increases, so too does the number of different bands of light required to make the measurements. Further, because a fairly high intensity of light over a fairly narrow spectral range is needed for these measurements, it has been found that the most successful sources of light for these measurements have been discrete, narrow-band emitters such as LEDs or laser diodes. These types of light sources are typically used because broadband sources (in conjunction with filters or a diffraction grating to obtain the required spectral bands) produce too little energy over the desired narrow spectral bandwidths to provide sufficient signal amplitude for photoplethysmographic measurements.
LEDs are inherently very quiet light sources but do not have a sufficiently narrow spectral bandwidth for use at all of the required center wavelengths. Conventional edge-emitting diode lasers provide the necessary narrow bandwidth but can be quiet noisy. For example, in a time-division multiplexed system, the intensity of the light emitted by a laser diode can vary from pulse to pulse, or can even jump almost instantaneously during any given pulse. These intensity variations can easily be large enough to prevent the measurement of the desired blood analytes to clinically-acceptable accuracy and precision levels. While not all types of laser diodes are noisy, often the photoplethysmographic instrument designer must use an inherently noisy light source if it is the only one available that has the required bandwidth and center wavelength needed for measurement of the desired blood analytes.
Vertical cavity surface-emitting lasers (VCSELs) can be very quiet but are generally unavailable at wavelengths shorter than about 800 nm. Thus for the shorter wavelengths it is often necessary to use an inherently noisy edge-emitting laser diode. Unfortunately, the noise levels in this type of laser have made the development of commercially viable photoplethysmographic devices based on these types of light sources impossible as the magnitude of the laser noise simply introduces too much error into the desired analyte measurements.
One of the reasons for the noise in the output of edge-emitting lasers is that once the laser is energized, the semiconductor junction temperature increases and the length of the laser cavity begins to change due to thermal expansion of the semiconductor die. If the cavity length changes, the original lasing wavelength of the device will no longer be the optimal wavelength for the new cavity length, because it will not fit inside the cavity with a whole number of wave periods. When this occurs a new lasing wavelength will become dominant within the cavity, essentially xe2x80x9ccrowding outxe2x80x9d the wavelength that was previously lasing. When this transition occurs there is also a small instantaneous change in the output optical power. It is these sudden changes that cause the noise that is seen at the output of these noisy light sources.
Mode hopping is only one source of light intensity noise. Other types of emitters can introduce noise as well. Tungsten light sources, for example, can be noisy just due to movement of the tungsten filament in the bulb. This type of broadband light source has been used in the past in photoplethysmographic instrumentation. To obtain the necessary spectral content the light from this element can be filtered by narrowband filters or spectrally dispersed by a diffraction grating. In either case the photoplethysmographic signals derived from these types of light sources can have high enough noise levels to cause large inaccuracies in the desired measurements.
It is important to recognize that as the number of blood analytes to be measured by a single photoplethysmographic device increases, the number of light sources (or at least the number of channels) also increases, and the effects of even very small amounts of noise are more and more noticeable. This is directly attributable to the fact that each photoplethysmographic signal, originating from each emitter, is simultaneously reading multiple blood analytes. As a result the light levels of each channel must be read with higher accuracy, and the detrimental effect of any given amount of noise on that channel is greater.
It has long been recognized by the medical community that conventional pulse oximetry is inaccurate in the presence of additional species of hemoglobin beside oxyhemoglobin and reduced hemoglobin. Steven J Barker, M.D., in a 1987 article entitled xe2x80x9cThe Effect of Carbon Monoxide Inhalation on Pulse Oximetry and Transcutaneous P02,xe2x80x9d published in the journal Anesthesiology, explained the errors in pulse oximetry caused by elevated levels of carboxyhemoglobin. Two years later in another Anesthesiology article entitled xe2x80x9cEffects of Methemoglobinemia on Pulse Oximetry and Mixed Venous Oximetry,xe2x80x9d Barker defined the errors in pulse oximetry readings caused by elevated methemoglobin levels. These articles, along with numerous case studies, make clear the long-standing need for a pulse oximeter capable of measuring all four primary species of hemoglobin. Additionally, the Pologe patent, U.S. Pat. No. 5,891,022, from 1999, the Pologe et al patent, U.S. Pat. No. 5,790,729, from 1988, and the Barthelemy et al patent U.S. Pat. No. 5,413,100 from 1995, all recognized the need for the use of multiple laser diodes to measure the additional blood analytes discussed above. These patents demonstrate the understanding that multiple laser diode based emitters, with carefully selected center wavelengths, must be combined to create an instrument capable of measuring the four primary hemoglobin species.
Despite the long-standing recognition of the clinical need for this type of instrument no photoplethysmographic device exists to measure these four species of hemoglobin. The primary problem that continues to prevent these ideas from developing into a commercially viable instrument is the high noise level inherent in most commercially available laser diodes.
In the design of a multi-parameter photoplethysmographic device, it is necessary to use emitters that have narrow bandwidths and mathematically-selected center wavelengths to allow for the measurement of the desired blood analytes. This can necessitate the use of inherently noisy light sources. Unfortunately these noisy sources distort the very photoplethysmographic signals that are necessary for these measurements. Thus it is necessary to find a way to utilize these noisy sources and still make analyte measurements to the required levels of accuracy and precision.
In the science of photoplethysmography, light is used to illuminate, or trans-illuminate, tissue for the purpose of measuring blood analytes or hemodynamic properties or parameters. In making these measurements it can become necessary to use light from a number of different types of sources including, but not limited to, incandescent bulbs, light-emitting diodes (LEDs), and lasers. The use of laser light sources becomes necessary when very narrow spectral bandwidth (narrow band) light is required to make possible the accurate photoplethysmographic measurement of certain specific blood analytes or the simultaneous measurement of a number of blood analytes such as oxyhemoglobin, reduced hemoglobin, carboxyhemoglobin, and methemoglobin. It is the purpose of this invention to allow accurate photoplethysmographic measurements using inherently noisy light sources that otherwise have desirable optical properties, including precisely tunable or selectable center wavelengths and high output intensity over a narrow spectral bandwidth.
This invention combines the use of at least one relatively quiet optical source with any number of noisier optical sources. For example, in one embodiment of this invention, a light emitting diode (LED) is used in combination with a number of edge-emitting laser diodes to provide all of the required spectral bands (of light) necessary to measure the target analytes. In this example, the targeted blood analytes include oxyhemoglobin, reduced hemoglobin, carboxyhemoglobin, and methemoglobin. The laser diodes provide high-intensity, narrowband, albeit relatively noisy, outputs at the center wavelengths that are required to allow measurement of these blood analytes. The LED provides an optically stable (also referred to as quiet or clean) output that is used, at least in part, to minimize the effect of the noise that is inherent in the laser sources.
As any noise in the input light sources becomes noise in the photoplethysmographic waveforms that are received by the photodetector, this intensity noise distorts the waveforms used to determine the blood analyte levels and can dramatically increase the inaccuracy of the measurements. Note also that if there is a reduction in the patient""s perfusion at the sensor site (the position on the tissue where the sensing light enters and is received from the tissue-under-test), there is a dramatic increase in the errors in the analyte measurements because although there is a fixed amount of intensity noise inherent in the light sources, this noise becomes larger in proportion to the pulsatile component of the photoplethysmographic waveform. This invention provides a way to utilize a quiet (or relatively quiet) light source to eliminate or at least minimize the effects of light intensity noise generated by inherently noisy (or relatively noisy) light sources in a photoplethysmographic device.
In this invention a quiet source, in this example the LED, provides a quiet photoplethysmographic waveform which acts as a xe2x80x9ctemplatexe2x80x9d that is used to eliminate, or at least minimize, the noise inherent in the photoplethysmographic waveforms generated by the noisier sources.
In an ideal photoplethysmographic device, different light sources emit light that is incident on the tissue-under-test through essentially the same small output aperture. The light from each source then ideally passes through the tissue traversing the same optical path. This generates a set of photoplethysmographic waveforms, one for each emitter, which are received by the detector, typically a silicon photodiode or equivalently any type of photodetector that is sensitive to the wavelengths of light emitted by the sources. The light signals from the different sources are kept separate from each other by any one of a number of different electronic schemes such as time-division multiplexing, where only one light source is turned on at a time and all the emitters are cycled through in rapid succession. Another scheme sometimes used is frequency-division multiplexing, where each light source is modulated at a different frequency. These are well-defined techniques in the art of electronics in general which have both been extensively used in the past in photoplethysmography, and will thus not be further explained herein.
In a perfectly noise free system, each photoplethysmographic waveform can be mapped into any other waveform by nonlinear amplitude scaling. In photoplethysmography the transform that scales one waveform into another is known; what is not known is the magnitude of the scaling that is required, as this depends on the level of the blood analytes and other absorbers in the tissue-under-test.
If the intensity noise generated by the noisy light sources is random in nature, a statistical least squares fit of the waveform from the quiet light source will allow the correct selection of the scale factors required to create a noise free (or at least quiet) version of the waveform data originating from any of the noisy light sources. This set of quiet photoplethysmographic waveforms can then be used in the calculation of the various desired blood analytes or hemodynamic variables. In this way the clean (or quiet) photoplethysmographic waveform has acted as a template to provide the correct waveshape for the noisy waveforms. This allows the use of noisy sources in the photoplethysmographic measurements, while eliminating or at least minimizing the error that would have been generated by the intensity noise.
The quiet light source used in the instrument may serve a dual role. It may provide the quiet light source for minimizing the effects of the noise in the noisy channels and it may also be one of the selected center wavelengths, or spectral bands, used for the analyte or hemodynamic measurements. The advantage of this is that the dual use of the quiet channels reduces the number of light sources required for the system, thus minimizing the complexity and cost of the instrument. In reduction to practice at the current time, the optimal light sources for the quiet channels will typically be either LEDs or VCSELs. The term xe2x80x9cchannelxe2x80x9d is used to indicate those data associated with the light out of the tissue-under-test, picked up by the sensor photodetector, originating from any given emitter. These data can be in the form of light levels, current levels, voltage levels, or mathematical values after conversion of the analog signals to digital values.
In this patent the term xe2x80x9ctemplatexe2x80x9d is used in conjunction with any technique in which the data from the quiet channel (or channels) is utilized to minimize the effects of the noise in the noisy channels. The template is the clean, or relatively noise free, photoplethysmographic data. The conceptually simplest technique, where the waveshape of the quiet channel is scaled to fit the data from the noisy channels, is explained above. This is just one of a number of ways of performing the noise elimination using a known clean channel. A second method, utilizing linear regression of differential absorption measurements, is described in detail below. While the two techniques are mathematically different, they both use the quiet channels to clean up the noisy ones, and therefore the quiet channel is still considered to be a template.

Stabilization of noisy optical sources in photoplethysmography


Embodiments of the inventive technology may provide a leaked fluid detection and response system in one aspect, and in another aspect, an environmental enclosure for at least a component of such leaked fluid detection system. Various embodiments of the leaked fluid detection and response system may provide wireless communication of detected leaks and a PLC that automates response and provides information regarding the presence of a leak. Enclosures may, in various embodiments, comprehensively surround enclosed components, thermally insulate enclosed components, include a leaked fluid capture basin, be aerodynamically streamlined, and/or be vermin-tight.

The inventive technology, in particular embodiments, provides an apparatus and method for protecting the natural world/surrounding environment from leaks in the well-based, underground resource recovery (e.g., U3O8 in-situ leach mining) environment which might lead to undesired consequences such as contamination of the surface water for wildlife, contamination of plants, as well as loss of production and costly clean up, etc.
Mining operations involving wells (whether in-situ leach mining, domestic water recovery, oil recovery, natural gas recovery, or mineral mining generally, as but a few examples) necessarily involve conduit conveyance of fluid (whether gaseous or liquid) under pressure. Often, particularly at an interface of earth and atmosphere (e.g., above ground, atmosphere-exposed, even where the ground has been lowered) where thermal stresses and thermal cycling may be extreme (e.g., temperature extrema may be more than 30 degs. C apart in particular locations), fluid leaks may develop. Such leaks, of course, if not detected and resolved in some fashion, may contaminate the immediate environment and compromise mining operations. Indeed, governmental regulations may soon require mining companies mitigate environmental impact due to such fluid leaks by mandating leak detection and/or leaked fluid capture. Particular embodiments of the inventive technology may seek to mitigate deleterious environmental impact due to such leaks, whether by providing an automated detection and notification system, and/or providing environmental enclosures for wellheads that may attenuate thermal cycling and reduce the risk of leaks while also improving the reliability of leak detection systems.

Method and apparatus for mitigating environmental impact due to fluid leaks


An information storage apparatus that includes a memory unit, a first controller that reads data from the memory unit, and a second controller included in the memory unit that reads a first identification and outputs the first identification in response to an external instruction, wherein the first identification may only be read by the second controller.

Recently, various media such as a DVD (Digital Versatile Disc), a Blu-ray Disc (registered trademark), or a flash memory have been used as a data recording medium. Particularly, recently, memory cards such as Memory Sticks (registered trademark), SD cards, USB memories in which a flash memory having a large storage capacity is installed have been actively used. A user may record content such as music or movies in these various information recording media (media) and install the information recording medium in a reproducing apparatus (player) to reproduce the content.
In addition, in recent years, the content has been actively distributed through a network, and the form of a process of purchasing the content by the user has been gradually shifted from a process of purchasing a disc where the content is recorded in advance to a process of downloading the content from a server connected to the network.
As specific forms of the content purchasing, besides the process of purchasing the media such as ROM discs, there are the following forms of the content purchasing.
(a) EST (Electric Sell Through) where a user apparatus such as network connectable terminal or PC is used to be connected to a content provision server, so that the content is downloaded.
(b) MoD (Manufacturing on Demand) where a public terminal installed at a convenience store or a public space such as a train station is used to record the content on a medium (memory card or the like) of a user.
In this manner, if the user has a medium such as a memory card for recording the content, the user may freely select and purchase a variety of content from various content sources such as a content provider and record the content on the medium of the user.
In addition, the processes of EST, MoD, or the like are disclosed in, for example, JP-A-2008-98765.
However, copyrights, distribution rights and the like to a large amount of the content such as music data or image data are reserved by the producer or seller. Therefore, in the case where the content is to be provided to the user, there are predetermined limitations on use. In other words, only a user having a legitimate right to use is permitted to use the content, so that control is generally performed to prevent unregulated use of such unauthorized copying.
As one of the regulations of content use control, there is a CPRM (Content Protection for Recordable Media). For example, this is a control configuration where the content is encrypted and recorded on the data recording media such as a memory card, a verification value based on an ID unique to the medium (media ID) is recorded, a verification process based on the verification value is performed during reading of the content from the media, and the content use control is performed. Herein, with respect to the media IDs, it is assumed that different IDs are separately recorded on the different media.
However, for example, in the current state, it may not be said that the management where different unique IDs are recorded for each memory card such as an SD card is reliably performed.
FIG. 1 illustrates a sequence of manufacturing a general memory card. As illustrated in FIG. 1, the memory card 10 includes a controller unit 11 and a flash memory unit 12.
The controller unit 11 is manufactured by a controller manufacturing company (controller vendor) 20 which manufactures the controllers.
In addition, the flash memory unit 12 is manufactured by a flash memory company (flash memory vendor) 30 which manufactures flash memory units.
In a general process, the parts manufactured by the vendors are assembled in a final process so as to complete the media 10.
The media IDs are frequently recorded under the management of the controller vendor 20 as a manufacturer of the controller unit 11. There is no problem if the recording of the media ID is performed under the proper management on the controller vendor 20 side. However, in the case where the proper management is not provided, for example, a plurality of the media having the same media IDs are mass produced and supplied to the user.
If this problem occurs, it is impossible to perform the content management based on the aforementioned CPRM, that is, the content use control depending on a configuration where the media ID is a value unique to each of the media. As a result, there is the potential for unauthorized use of the content.

Data storage apparatus, information processing apparatus, information processing method, and program


Methods and systems for simulation of a testable system are provided in which a virtual testable system is used. One method includes inputting a system definition file into a translation utility, where the system definition file includes a plurality of physical addresses required for execution of the system definition file in the testable system. The method also includes inputting a memory map file into the translation utility, the memory map representing a virtual memory space for a virtual testable system. The method further includes generating virtual translation information by translating the physical addresses into virtual addresses using the memory map file.

Calibration of a system for determining an optimal operational configuration generally requires monitoring operation of the testable system, and adjusting one or more parameters affecting operation of the testable system until the system reaches a desired performance level. Observation systems exist which are configured to monitor the activity of the testable system so that calibration of that system can take place. One possible system requiring testing and calibration is an Electronic Control Unit (ECU), such as those found in vehicle control systems for determining fuel consumption, monitoring exhaust gas valves, and other physical characteristics of the vehicle.
Monitoring of such testable systems, such as ECUs, can be time consuming and difficult due to manufacturing timing and other physical constraints. For this reason, it is sometimes advantageous to model the activity of the testable system in software in order to determine the parameter combinations which will provide the desired result, such as improved performance, accuracy, or some other measure of the testable system's activity. Modeling of a testable system can include use of a virtual testable system, such as a separate, adjustable software model useable to represent the actions of the testable system. The virtual testable system may then be simulated and its activity monitored.
Due to differences between the testable system and its counterpart virtual testable system, the virtual testable system often executes in conjunction with a separate simulation or observation system monitoring its activity, different from the observation system which would be used to monitor the testable system. Use of different observation systems for physical and virtual systems adds expense to the testing and calibration process.
Therefore, improvements are desired.

Address translation system for use in a simulation environment


A method of creating a multicellular blood-brain barrier model is disclosed. In one embodiment, the method comprises culturing primary brain microvascular endothelial cells or embryonic stem cell-derived endothelial cells upon a permeable support in the presence of neural progenitor cells.

The blood-brain barrier (BBB) is composed of a specialized class of endothelium that forms a cellular barrier between the bloodstream and the interstices of the adult brain. By restricting non-specific flux of blood-borne constituents, the BBB plays an important role in maintaining parenchymal homeostasis, and strictly regulates transport of ions, small molecules, proteins, and cells into and out of the brain. The BBB accomplishes these tasks because its unique endothelium is endowed by epithelial-like tight junctions joining adjacent endothelial cells, lacks fenestrae, and possesses a rich array of molecular transport systems. Although the endothelium is the principle determinant of barrier function, perivascular non-endothelial cells in the local microenvironment have been shown to make significant contributions. Astrocytes (Stewart and Wiley 1981; Risau et al. 1986b; Janzer and Raff 1987), neurons (Tontsch and Bauer 1991) and pericytes (Balabanov and Dore-Duffy 1998; Ramsauer et al. 2002) have all been demonstrated to provide cues that result in the unique BBB endothelial phenotype.
Although the inductive properties of the aforementioned brain cell types have been confirmed through a multitude of in vivo and in vitro studies, the cell type(s) responsible for early embryonic BBB induction have not been distinguished. The developmental timecourse of embryonic BBB formation differs between species, but it is generally well accepted that the onset of BBB development begins prenatally and is followed by a gradual maturation to full BBB function (Bauer and Bauer 2000; Engelhardt 2003). For example, in rodents, vascular fenestrae disappear, pinocytosis decreases, and vessels decrease in diameter between embryonic days E11 and E17 (Bauer et al. 1993; Stewart and Hayakawa 1994; Bolz et al. 1996). The onset of tight junction formation is detectable from day E15, and tight junctions continue to increase in complexity through postnatal day P1 (Butt et al. 1990; Schulze and Firth 1992; Bauer et al. 1995; Kniesel et al. 1996; Nico et al. 1999). During this time, the transendothelial electrical resistance (TEER) of pial vessels is intermediate between peripheral vessels and the adult BBB (Butt et al. 1990; Schulze and Firth 1992; Bauer et al. 1995; Kniesel et al. 1996; Nico et al. 1999). A combination of the aforementioned attributes serves to restrict passage of protein into the embryonic brain (Risau et al. 1986a; Bauer et al. 1995; Dziegielewska et al. 2000), while a gradual decrease in BBB permeability to small tracers such as inulin and sucrose begins during embryonic development and continues postnatally (Ferguson and Woodbury 1969). Finally, transporter expression at the BBB also evolves from embryonic to postnatal stages as a result of changing nutritional needs (Johanson 1989; Gerhart et al. 1997).
The early embryonic developmental timecourse for the BBB raises the question as to what inductive factors or cell types drive the endothelial differentiation process. As mentioned above, astrocytes have long been linked with induction of BBB properties by in vitro and in vivo experiments (Stewart and Wiley 1981; Risau et al. 1986b; Janzer and Raff 1987). However, angiogenic vessels invade the immature embryonic neural environment and begin establishing BBB characteristics well in advance of the onset of gliogenesis as defined by the presence of GFAP-positive astrocytes in rodent brain (E18, (LeVine and Goldman 1988)). In addition, the developing BBB vessels have little extracellular matrix with few astrocyte contacts even just days prior to birth (Caley and Maxwell 1970). In fact, for rodents, much of the astrocyte generation takes place postnatally during which time the astrocyte sheath that surrounds mature brain capillaries is developed (Johanson 1989). Therefore, it is unlikely that astrocytes function in the early BBB induction process, but instead other cell types may be responsible for the early onset of BBB properties.
NPC are a major cell type in the developing embryonic brain, and it was recently reported that the differentiation and morphology of NPC are influenced by endothelial cells (Shen et al. 2004). In co-culture with endothelial cells, NPC show reduced neurogenesis and elevated self-renewal (Shen et al. 2004). Neural progenitors have also been observed in contact with early postnatal blood vessels, and this was implicated as an early stage in astrocyte differentiation (Zerlin and Goldman 1997). In addition, when endothelial cells and neural stem cells are grown in direct contact, it was shown that the adult neural stem cells could even produce progeny that exhibited an endothelial phenotype (Wurmser et al. 2004). Finally, adult neural stem cells are often found localized in perivascular spaces of the brain such as the subventricular zone and hippocampus, and it is thought that the vasculature is an important part of the stem cell niche (Doetsch 2003b).
Given the cellular interplay in the endothelial cell to NPC direction, we examined herein whether NPC could also influence brain endothelial cell phenotype. In this specification, we demonstrate that NPC isolated from the E14 embryonic brain induced BBB properties in an in vitro model consisting of primary rat brain microvascular endothelial cells in co-culture with NPC. We disclose an improved BBB model and method for examining the permeability of the BBB to test compounds.


The present invention relates to a connector assembly (3) for connection to a container (1) for sterilising goods, preferably for pharmaceutical applications, and a releasable connector port (5) for releasably connecting said connector assembly (3) to a treatment station (1) for the goods that is contained in said container (1). Said connector assembly (3) further includes a second port that initially is provided with a detachable rapid transfer port cap (4), which cap (4) corresponds to a rapid transfer port means (15) that is provided at a goods transfer station (12). The connector port (5) and the rapid transfer port cap (4) are in fluid connection via a good stopper means (7). The invention also relates to a multi-treatment sterilising system and to a method for transferring sterilised goods from a multi-purpose container using a system according to the invention.

The present invention relates to a connector assembly including an end portion for connection to a sterilisation container. The connector assembly includes a releasable connector port for releasably connecting said container assembly to a treatment station for multi-purpose treatment of goods, such as plugs, that is enclosed in said container.
The invention also relates to a multi-treatment sterilising system, including a multi-purpose container for treatment and storing of articles being enclosed there within. Finally, the invention relates to a method for transferring sterilised goods from a multi-purpose container using a system according to the invention.
When sterilising small articles, such as plugs or caps for pharmaceutical purposes, it is known to use a multi-purpose container, in which the articles are submitted to several different treatments such as washing; sterilising and drying. Rubber plugs are usually also siliconised, all within the same multi-purpose container. Siliconising is a procedure for providing the plugs with a thin layer of silicon oil, which makes the introduction of the plugs into pharmaceutical test tubes easier.
After treating the goods in the container, it is desirable to store said container in a manner such that the risk for contamination of the sterilised goods is eliminated. In order to achieve this, the container is pressurised before storing so that the internal pressure of the container is greater than the ambient pressure.
After storing, the goods are to:r be transferred to suitable packages. This must be done in a sufficiently clean environment, such as a clean room or isolator. A problem occur however in keeping the environment clean when it is confronted with the container that has been stored under unclean conditions. To avoid this problem, the exterior of a port of the container has to be sterilised before transfer of the goods into the clean environment through said opening. The procedure for sterilising the port is however time-consuming and difficult to handle. There is also a risk that an un-sterilised port may be inserted into the clean room by mistake, since there is no way to immediately determine whether said port is clean or not.
The aim of this invention is to eliminate the above mentioned problems during transfer of the sterilised goods to a clean environment. The aim is also to provide a sterilising system where these problems do not occur, and which operates quickly and safely. Additionally, the aim is to provide a method using such a system.
The first of the above mentioned aims is reached by a connector assembly according to the introduction in which said connector assembly further includes a second port that is initially provided with a detachable rapid transfer port cap that corresponds to a rapid transfer port means in a transfer station. The connector port and the transfer port are in fluid connection via a goods stopper means. Said goods stopper means prevents the goods from passing through the connector port when said cap and said means are interconnected for transfer of the goods via the second port to the transfer station.
With goods stopper means we here refer to a means which stops goods from passing through it, but allow fluid to pass through. Such a means could for example be a perforated plate, even though many other designs are possible.
With rapid transfer port cap we do here refer to one of the double doors used in rapid transfer ports such as described in for example EP 0 586 307, SNE LA CALHENE. These kinds of ports consist of a rapid transfer port means, comprising a door and a doorframe that is to be arranged at a clean room wall. The door is inter-connectable with a rapid transfer port cap that seals a container containing the clean goods. When interlocking, one side of the rapid transfer port cap that has been directed outwards from the container and thus could have been contaminated during storing, is locked together with the outer side of the door of the rapid transfer port means. The xe2x80x9cdouble doorxe2x80x9d comprising the interlocked door and cap can then be opened, while substantially all contamination is safely held between the cap and the door.
According to the invention, there is a connector port assembly comprising one connector port for connection to a treatment station. This connector port can be designed as the ports used in prior art. There is also second port that initially is covered by a detachable transfer port cap. This port will later be used as a transfer port when the cap has been removed and the goods are to be transferred to a clean environment outside of the container. The use of a rapid transfer port thus eliminates the need of sterilising a port of the container for transfer of the sterilised goods.
Performing sterilisation of a port according to prior art takes about 30-40 minutes, while the interconnection and opening of the rapid transfer port takes only about 5-10 minutes. A connector assembly according to the invention thus makes the transfer procedure much more time efficient than the procedures according to prior art.
The function of the goods stopper means is as follows. When the container is connected to the treatment station via the connector port, the transfer port and thus the inside of the rapid transfer port cap will be sterilised as well as the goods inside of the container, since the goods stopper means provide fluid contact between the connector port, where the sterilising medium is supplied, and the rapid transfer port cap.
At a later stage, when the sterilised goods are to be transferred to a clean room for for example packaging, the container is directed so that the rapid transfer port cap is aligned essentially vertically. After removal of the transfer port cap, the goods will flow down through the rapid transfer port opening. Because of the stopper means, no articles will fall in to the dead end of the connector port.
Preferably, said rapid transfer port cap is arranged adjacent to the connector port. This will make the procedure when using and manufacturing the connector assembly considerably easier.
Said connector assembly could advantageously be essentially Y-shaped, with the connector port and the rapid transfer port cap being provided at the arms of the Y, respectively. The base of the Y-shaped connector assembly is constituted by an end portion for connection with the container. In such an embodiment, the different ports are easily handled, since changing between the ports can be made simply by rotation of the connector means and/or the container.
Preferably the connector assembly is provided at an end of the container, that is directed upwardly during treatment and downwards during transfer of the content in said container. During treatment, when the connector assembly is directed upwards, no liquids or fluids can be stored in the connector assembly. During transfer, the connector assembly, or at least the rapid port cap should be directed downwards to empty the container merely by help of gravity.
The connector assembly is advantagely provided with a sensor for detecting the presence of the rapid transfer port cap on said container. If the sensor shows that no rapid transfer port cap is present, the sterilisation process would not continue. The sensor provides thus an easy control device to ensure that the treatment process of the goods is performed properly.
The invention further relates to a multi-treatment sterilising system, including a multi-purpose container for treatment and storing of articles being enclosed there within, at least one treatment station, a transport means and a transfer station for transferring said objects into a clean area for further processing such as packing, and being characterised in said system including a connector assembly according to the invention, which assembly is arranged at the container.
Preferably said transfer station includes rapid transfer port means corresponding to the rapid transfer port cap of the connector assembly. The transfer station could also be provided with glove ports for manually interconnecting the rapid transfer port means and the rapid transfer port cap for detachment of said rapid transfer port cap from said container. The process of interconnecting the rapid transfer port cap with the rapid transfer port means to form the double port, which contains any eventual contamination, is so delicate with ports available today, that it can only be made by hand. Therefore, glove ports are necessary to allow manual interconnecting of the means and cap.
Advantageously, said transfer station can be provided with a feed pipe that is pivotably arranged to be movable from a position away from the container to a position extending through the opened rapid transfer port of the container. When the rapid transfer port is open, i. e. the cap and means are interconnected, there is still a small risk of contamination from the sides of the doorframe in which the door was initially disposed. To avoid spreading of this contamination to the sterilised goods, the feeding pipe can be inserted through the opening of the rapid transfer port and thus provide a clean outlet channel for the sterilised goods in the container.
Finally the invention also relates to a method for transferring sterilised goods from a multi-purpose container using a system according to the invention. The rapid transfer port cap of the connector assembly and the rapid transfer port means of the transfer station are then manually interconnected to remove said cap from the container, using glove ports for manually handling the means and cap.


A highly effective petroleum-based mosquito larvicide having dispersed therein minor amounts of a dialkyl polysiloxane and an ethoxylated mono-alkyl phenol.

The killing of mosquito larvae and pupae by application of petroleum oil toxicants on their aquatic breeding grounds is well known. To be effective toxicants, particularly for insecticide-resistant strains, such as Aedes nigromaculis and Culex tarsalis, relatively high volumes of refined petroleum oils are generally applied on the aquatic breeding areas, e.g., 4-6 gallons per acre. At those volumes (concentrations), phytotoxicity and animal toxicity become problems, and often the resultant increase in larvae mortality is small or even negligible. Surfactants are sometimes added to the petroleum oils to increase their effectiveness as larvicides or pupicides.
U.S. Pat. No. 2,988,473 to Mallis et al., for insance, issued on June 13, 1961 and incorporated herein by reference, discloses a composition consisting essentially of a petroleum hydrocarbon oil having insecticidal properties and boiling in the range from 300.degree. -800.degree. F., and from about 0.001 to 2.0% by weight of a liquid organo-polysiloxane, e.g., dimethyl polysiloxane. According to the patent, the polysiloxane increases the insecticidal activity of the oil, and emulsions made with the oil, in household sprays for flies, cockroaches, mosquitos, moths, and the like. However, the use of a larvicidal petroleum oil boiling in the range of 500.degree. - 675.degree. F., fortified with dimethyl polysiloxane, for instance, adds measurably nothing to the larvicidal or pupicidal activity of the petroleum oil at a volume application of about 2.0 gal/acre.
U.S. Pat. No. 3,499,969, issued to Chambers on Mar. 10, 1970, discloses a mosquito control oil consisting essentially of a hydrocarbon oil boiling between 400.degree. and 800.degree. F. and containing from about 0.2 to about 3.75 weight percent of a polyethoxylated 2,4-dinonyl phenol in which the component has an average of from about 6 to 14 ethoxy units. In columns 4 and 5 of this patent, scattered, it is indicated that the presence of aromatic hydrocarbons, such as the closely-related ethoxylated nonyl phenol or other surfactant, inhibit the larvicidal activity of the oil composition. Furthermore, and most importantly, the patent states that when ethoxylated nonyl phenol is present greater than normal amounts of the ethoxy dinonyl phenol are required to restore the original larvicidal activity. In other words, this patent teaches that ethoxylated nonyl phenol is not recommended as an additive to a petroleum larvicide or pupicide because it inhibits the toxicity of the oil composition. Moreover, in Table V, column 5, of this patent, it is shown that even ethoxylated dinonyl phenol, when it contains less than six ethoxy groups, exhibits seriously diminished larvicidal activities. This patent is also incorporated herein by reference.
Column 2, line 48- 55, of Chambers is most dissuasive;
"A number of other surfactants have been checked, and no other surfactant has been found to give the same effect as the ethoxylated nonyl phenols (9 species) and ethoxylated octyl phenols (5 species) with various numbers of ethoxy units in the substituent; ethoxylated amines (2 species); ethoxylated fatty acids (2 species); and 9 other ethoxylated materials."
Table II of the Chambers patent contrasts the activity of its claimed surfactant, i.e., ethoxylated (8) dinonyl phenol (EODP) (8), with the ethoxylated (5) octyl phenol claimed herein:
TABLE II ______________________________________ Interfacial Percent mortality, tension 24 hrs. exposure larvae Description of material dynes/cm. 1.25* 2.5* 5.0* ______________________________________ 500-600.degree. F. paraffinic oil with 0.5 wt. percent ethoxylated (5) octyl phenol 2.2 -- 36 89 500-600.degree. F. paraffinic oil with 0.375 wt. percent EODP (2) 1 100 100 -- ______________________________________ .sup.1 Gallons per acre. .sup.2 EODP (8) is ethoxylated 2,4-dinonyl phenol having 8 ethoxy units (average).
According to the present invention, a high-boiling refined petroleum oil fortified with two specific surfactants each in a specific concentration range is made available; it has a low volume application, i.e., less than 2.5. gallons per acre, and preferably in the range of between 1 to 2 gallons per acre; it has excellent film-forming and spreading characteristics; it has low "mist volatility" when sprayed by aircraft; it produces a cohesive film of oil on the surface of a body of water; and it is an effective toxicant even against resistant strains of mosquito larvae, without destroying the surrounding animal and vegetable life. The oil alone, or the oil with one or the other surfactant, at this application rate is not as effective and thus unsatisfactory. The surfactants of the present petroleum oil composition are an ethoxylated mono-alkyl phenol having 2-5 ethoxy groups and a dialkyl polysiloxane, as hereinafter more fully described.
Generally, any refined petroleum oil of low aromatic content can be used in the present composition, such as a vacuum distilled, solvent extracted, fractionated and hydro-treated naphthenic raffinate having larvicidal activity, which, of itself, or when combined with either a dialkyl polysiloxane or an ethoxylated mono-alkyl phenol, is not an acceptable larvicide when applied on aquatic breeding grounds at the rate of less than about 2.5 gal/acre, but which, however, is very effective, particularly with regard to resistant strains of mosquito larvae, as stated above, when the larvicidal petroleum oil is combined with both the dialkyl polysiloxane and the ethoxylated mono-alkyl phenol within the concentration ranges hereinafter described and claimed. Combinations of other surfactants with petroleum oils are not as effective as larvicides, are often toxic to plants and animals, and are not part of the present larvicidal petroleum oil composition.
Larvicidal petroleum oils generally employed in the present composition are those derived from a neutralized naphthenic crude. They are generally refined by vacuum distillation, solvent extraction, fractionation and hydrogenation, and boil substantially within the range of about 500.degree. - 750.degree. F., as described in U.S. Pat. No. 2,096,885, to Donlan, issued Oct. 26, 1937, for instance, or as described in U.S. Pat. No. 2,405,775, to Bradley, issued on Aug. 13, 1946. Refined mineral oils may be effectively employed herein, but are economically impractical for larvicidal use. It is particularly preferred to use a larvicidal vacuum distilled, solvent extracted, fractionated and hydro-treated naphthenic raffinate boiling in the range of about 550.degree.-675.degree. F., of low aromatic content, i.e., having an unsulfonated residue of over 90 and an API gravity of, for instance, between 25-31.
The composition of the present invention includes the larvicidal petroleum oil having dispersed therein a combination of about 0.3-2.0 weight percent of an ethoxylated C.sub.8 - C.sub.12 phenol having 2-5, and preferably 3-4 ethoxy groups, and about 0.2- 0.8 weight percent of a dialkyl polysiloxane, and preferably 1.0- 1.2 and 0.3- 0.4 weight percent of each, respectively.
It is an additional advantage of the present composition that it is stable under normal storage conditions, i.e., no evidence of separation of the surface active agents from the oil.
The preferred ethoxylated mono-alkyl phenol is nonyl phenol having 3- 4 ethoxy groups, although generally C.sub.8 - C.sub.12 mono-alkyl phenols having from 2- 5 ethoxy groups, such as ethoxylated octyl, decyl and dodecyl phenol, for instance, can be employed in the present composition.
The dialkyl group of the polysiloxane may be lower alkyl, i.e., methyl, ethyl, propyl or isopropyl, for instance, but because dimethyl polysiloxane is readily available and less costly, it is particularly preferred. The higher alkyl substituted, i.e., over C.sub.5, and aryl polysiloxanes, such as diphenyl polysiloxane, are not preferred because of cost, availability or both. Dialkyl polysiloxanes having a viscosity of about 50 cs at 25.degree. C. are preferred for ease of dispersion in petroleum oil at ambient temperatures.
It is indeed surprising, in view of the teachings in U.S. Pat. No. 3,499,969, supra, that the presence of the preferred ethoxylated nonyl phenol, and one having 3- 4 ethoxy groups, not only enhances the toxicity of the present composition as a larvicide when used in combination with a dialkyl polysiloxane, but in addition, it contributes to a well-balanced composition, which tests of aerial spraying show settles on the surface of a body of water as an effective cohesive larvicidal film.
The range of concentration of each surfactant in the petroleum oil, as set forth above, is effective and practical. That is to say that the present composition is not as effective a larvicide at the low volume application, supra, when quantities of surfactants fall below the lower, limits, and, although amounts above the upper limits are tolerated, it becomes impractical to use such excesses because the efficacy of the composition remains the same.
The mono-alkyl phenol/ethylene oxide condensation products are well known in the art and may be purchased under the trade names "Emcol (T24)", sold by Witco Chemical Corporation and "Surfonic N-40", sold by the Jefferson Chemical Company. The dialkyl polysiloxanes, particularly the preferred dimethyl polysiloxanes, are also well known and may be purchased under the trade name of "DC - 200 Fluid", manufactured by the Dow-Corning Company, preferably having a viscosity of about 50 cs at 25.degree. C., as stated above.
Moreover, as also stated above, when only a di-alkyl polysiloxane additive is present, as disclosed in the Mallis et al. patent, supra, spreadability of the oil composition, when sprayed on a body of water at the rate of about 1- 2 gallons per acre, is poor, and the larvae and pupae kill is not enhanced. Likewise when only the ethoxylated mono-alkyl phenol is present, cohesion of the oil composition on water is poor and the larvae and pupae kill is poor. The oil dispersion of the present combination of surfactants, in the specific concentration ranges, is, as stated above, well balanced, has an excellent spreading rate and excellent film coherence on a body of water, and quite unexpectedly the ethoxylated nonyl phenol additive, rather than inhibit toxicity of the petroleum oil, enhances the toxicity to larvae. Furthermore, the present preferred embodiment has no discernible phytotoxicity and/or animal toxicity, and can, therefore, be sprayed on water breeding areas without destroying surrounding vegetation and animal life, at the effective larvicidal dosage of less than 2.5 gallons per acre.
The present composition, as stated above, does not include the use of either surfactant alone, or any other surfactant or combination of surfactants. It includes only the combination of an oil-miscible ethoxylated long-chain mono-alkyl phenol having preferably 3- 4 ethoxy groups and an oil-miscible dialkyl polysiloxane, in specific quantities as set forth hereinbefore, dispersed in a larvicidal petroleum oil, preferably of a low viscosity, i.e., under 200 SUS at 100.degree. F. For aerial spraying, for instance, a petroleum oil having a viscosity of about 50- 75 SUS at 100.degree. F. is preferred.
Small quantities of other oil-miscible surfactants or toxicants, such as DDT, chlordane, lindane, malathion, and the like, or other additives which do not inhibit the larvicidal and pupicidal effects of the present composition, may be present without departing from the spirit of the present invention.
The following table summarizes the results of aerial spraying of a larvicide prepared according to the present invention and sprayed at the rate of (a) one gallon per acre and (b) two gallons per acre, respectively. The larvae population is determined both before and 24 hours after spraying, by sampling the same areas with a standard dipper. The larvae in the sample breeding areas are predominantly of the common species of mosquitos found in flooded pastures in California, such as Culex tarsalis and the Aedes nigromaculis, both species being resistant strains.
The larvicide is prepared by dispersing 1.0 weight percent and 0.3 weight percent, respectively, of ethoxylated nonyl phenol having 3- 4 ethoxy groups (Emcol T-24) and dimethyl polysiloxane (DC - 200 Fluid) in a refined naphthenic raffinate, of low aromatic content, boiling in the range of 550.degree.- 675.degree. F. and having a viscosity of 58 SUS at 100.degree. F.
TABLE ______________________________________ 24 - Hour Larvae Kill at 1.0 Gal./acre LARVAE POPULATION A- ver- Aver- No. age No. age of Total Per of Total Per % Location Dips Larvae Dip Dips Larvae Dip Mort. ______________________________________ A-Control* 47 22 0.47 52 36 0.70 -- B-Control* 49 147 3.00 48 180 3.75 -- C-Control* 78 95 1.21 43 66 1.53 -- ______________________________________ Before After Treatment Treatment ______________________________________ D 81 105 1.30 153 9 0.06 96% E 81 93 1.15 144 17 0.12 90% F 26 58 2.23 109 4 0.04 98% G 75 113 1.54 105 4 0.04 97% H 26 27 1.04 87 2 0.02 98% I 24 19 0.79 9 0 0.00 100% J 13 4 0.03 20 0 0.00 100% At 2.0 Gal./acre K 52 160 3.00 70 0 0 100% ______________________________________ *Control - No treatment (blind) ##STR1##