A switched mode drive circuit 10 comprises a first switch 14 having a first terminal 14.1 and a second terminal 14.2, a second switch 16 having a first terminal 16.1 and a second terminal 16.2, an inductive component 20 comprising at least a first winding part 20.1 having a first end 20.1.1 and a second end 20.1.2 and a second winding part 20.2 having a first end 20.2.1 and a second end 20.2.2 and an energy storage device 18 having a first pole 18.1 and a second pole 18.2. The first and second terminals of each of the first and second switches and the first and second ends of each of the first and second winding parts are connected in series over the first and second poles of the energy storage device and the first and second winding parts are configured in one of a common mode and a differential mode.

This invention relates to a switched mode drive circuit and method for an inductive component. The invention more particularly, but not exclusively, relates to buck, boost and push-pull drive circuits.
Drive circuits comprising a first switch having first and second terminals, a second switch having first and second terminals and wherein a terminal of the first switch, a terminal of the second switch and one end of an inductive component to be driven are connected to one another at a common node are known in the art. In push-pull configurations, transistors are used as the first and second switches and in buck, boost and buck-boost configurations, a diode is used as one of the switches.
In all these configurations, an energy storage device is connected over the terminals of the first and second switches that are not connected to the common node. In push-pull and buck configurations, the energy storage device comprises a DC power supply. In a boost configuration the energy storage device comprises an output capacitor and in a buck-boost configuration, the energy storage device may comprise a DC power supply and an output capacitor connected in series.
During normal operation, the switches are driven to be on and off in alternating relationship—that is when the first switch is on, the second switch is off, and vice versa. However, it is well known that it may happen that both the first and second switches are on at the same time, so that the energy storage device is short-circuited. This may result in large currents which may cause damage, such as damage to the switches.
Conventional protection circuits and methods are aimed at ensuring that the one switch is fully off, before the other switch is switched on. In push-pull configurations this may be achieved by inserting some delay between the switching off of the one transistor and before the other transistor is switched on. In buck and boost configurations a fast switching diode is normally used. In other embodiments a conventional series protection inductor comprising a magnetic core is used. As will be clear and will be described in more detail below with reference to FIG. 1, these techniques limit not only the maximum frequency of the drive circuit, but also the efficiency of the drive circuit.


A large animal trap (especially for wild hogs) that is easily moved by a single individual and takes only ten minutes to unload and set up and walk away. It is approximately 7½′ diameter across the center allowing a trapper to potentially catch a whole herd at once, but overall it is still light enough for a single individual to pick up and roll anywhere owing to its approximately circular drum shape. Overall, the trap includes 750+ welds making the trap exceedingly strong for its weight and size. The trap further includes triple offset walls to help keep all trapped animals in. In use, the trap is firmly secured to the ground by a chain and allows nothing to get out except turkeys which can fly out the escape hole in the top. It is easy, fast and fun to set the trap. A user only needs to tie the rope on the door and set the pins to engage the ground and suspend the door in the open position using the rope. A user then pours corn in and waits until the hogs come into the trap. When the wild hogs or other large animals in the trap root up the pins in the ground, the door drops and locks shut and you keep everything that came into the trap. Nothing gets out unless it flies. It is a fully assembled trap with no assembly required post purchase.

1. Field of the Invention
The invention relates generally to a one-person operable large animal trap. Specifically, the invention relates to an especially portable/maneuverable wild hog catching trap and method of using the trap.
2. Background
There is a need in the industry for a trap that can be operated by one person, man or woman of moderate physical capacity, in order to be able to trick a hog and catch it in a safe sturdy trap.
Most trappers use square traps requiring two or more people to manhandle. These traps need significant leg and back strength to move owing to their weight and awkwardness. In addition, you can only mostly truck these traps in to a spot close to a road. This is a significant disadvantage since in many cases hogs are in the bottom of valleys, away from road edges, feeding. If you want to trap them, you have to go to them. A further disadvantage of existing traps is that the longer the overall length of a traps, the more likely a hog can run and crash into the end of the trap. This can severely injure the trapped animal and damage the trap.
Most existing traps are square in shape and are just simply put together with only one wall and very little pre work. These animals are super strong in the wild so you have to be prepared for the unexpected owing to their desire to be free. Traps must be much stronger, especially if the whole herd is all caught at once. Some trap builders require you to fit and weld additional elements together to augment the strength of the traps.
Many of the existing traps are also home-made traps having only light walls, if any. For example, one wall might be only a wire panel without any sort of reinforcing. The disadvantage of this type of trap is that if a hog hits a one wall trap, it will almost tear off its bottom jaw, severely hurting itself in the process. There is often not much time spent in the construction of known traps. Corners are cut to keep costs down. Most trappers are looking for cheap and easy and are not concerned with strength and safety.


The invention relates to a dispensing device for a liquid container, notably for a container made of a flexible material housed in a substantially dimensionally stable outer container which encloses same and is penetrated by the dispensing device. Said dispensing device comprises a tubular part with an outlet opening which can be shut by a valve element. A tubular housing body is closed at one end by a membrane-like front disk in which a rod-like transverse element in which a valve tappet for a valve head originates which is assigned to the lateral outlet opening provided for in the tubular housing body. The valve tappet and valve head further form a monobloc unit made a plastic material which is softer than the material of the housing body or rod-like element, and the valve tappet is mounted on the rod-like element in the area of an articulated region.

The invention concerns a dispensing device for a liquid containerxe2x80x94in particular for a container of flexible material in a substantially dimensionally stable outer container which encloses the container of flexible material and is penetrated by the dispensing devicexe2x80x94, wherein a tubular part of the dispensing device has a laterally disposed outlet opening which can be closed by a valve element.
Combinations comprising a dimensionally stable outer container and an inner container of flexible material which is accommodated therein are known for storing liquid foodstuffs such as wine, salad oil or the like. The outer container which is for example of a cuboidal or parallelepipedic shape can comprise corrugated card and its inner container can be of a bag-like configuration consisting of heat-sealed plastic foil or sheet. Such systems are also referred to as xe2x80x98bag-in-boxxe2x80x99 containers.
In an opening in the inner container, a flange collar of a hollow coupling portion which is formed from plastic material can be welded to the inner container in liquid-tight and gas-tight relationship. Usually, pressed into that coupling portion is a tap or faucet or a bung; while the bung is pulled out for dispensing liquid, the re-closable tap for that purpose includes a valve element which is associated with the cross-section of an outlet opening.
For transport purposes, the tap is disposed within the outer container and, prior to being opened, is pulled through a pre-perforated portion of the outer container. In order in that situation to prevent unwanted actuation of the valve element the tap can additionally be provided with a seal. When the liquid flows out the flexible inner container collapses, that is to say its volume always matches the amount of liquid which is stored therein and oxidation processes due to air subsequently flowing thereinto therefore do not occur.
An aspect of significance in regard to taps or faucets of that kind is the sealing integrity thereof with respect to the ambient atmosphere; if the latter penetrates into the liquid container, the shelf life of liquid foodstuffs, for example wine stored in the inner bag, is considerably reduced. It will be appreciated that the sealing integrity of a tap made from plastic material is reduced reciprocally to the number of joins that it involves.
Besides a good flow speed for the container contents, the properties required of a tap of the described kind are that it should be simple to keep clean and that it should be of a configuration which facilitates injection molding.
A dispensing device of the kind set forth in the opening part of this specification is disclosed in EP 0 043 698 A1.
Here the valve element is a plug-like body on a pressure plate which is displaceable in the housing body; the pressure plate is connected by a rod-shaped intermediate element which in the closed position of the valve element extends substantially parallel to the longitudinal axis of the housing body, to a spherical portion of elastic material, as an actuating member arranged at the front end of the housing; that spherical portion is clampingly fixed by its edge to the housing body and deformed upon actuation of the intermediate element.
EP 0 553 956 A1 describes another dispensing device whose actuating member is also a pressure spherical portion which is fixed at one end to a housing body. Projecting substantially axially from the pressure spherical portion is a sliding pin which affords a sliding cam and which at its inner end includes a cylinder body having a sawtooth edge, as a penetration element, and whose sliding cam co-operates with the bar end of a valve element at the lateral outlet opening.
Rotational elements are unsuitable for so-called bag-in-box systems as the flexible inner container does not offer a sufficient resistance to turning movement. To open such a tap the tap or its coupling portion has to be held fast with one hand while the other hand is used to operate the valve element. A rotary tap with a valve cover which is rotatable by hand is to be found for example in DE 39 10 425 A1. Taps which can be opened and held at the same time with one hand are more suitable for a bag-in-box; in that way, the other hand remains available for firmly holding a vessel which is to be filled.
In order to keep the inner container free of oxygen before the first use of the inner container, the above-mentioned opening in the inner container can be closed by a plate or a plug which is removed before the first use occurs. There are also taps which, in addition to the valve element, also have a device for piercing the plate or for removing the plug from the opening in the container. In that case, the valve element can be connected to the piercing device, in which respect attention is directed to DE 32 12 232 A1. The latter describes a tap having a valve element and a closure device, in which the valve element and a plug of the closure device are arranged in coaxial successive relationship. Upon actuation of a resilient knob the valve element is removed from its valve seat; the tap opens as a result. In addition the valve element urges the plug towards the outlet and the opening in the container is opened.
EP 0 432 070 A discloses a tap having a housing body and a plunger which is loaded by a force-storage means. The plunger acts on a sealing diaphragm connected to the housing body.
The dispensing devices available hitherto for the bag-in-box systems are generally of a complicated and expensive design configuration and comparatively large amounts of plastic material are required for shaping them. Those dispensing devices are excessively cost-intensive both in terms of their manufacture and also in terms of stockkeeping. In addition, gas-tight sealing integrity is still defective; the taps available on the market include a large number of soft parts; however, they perceptibly reduce the gas-tight sealing integrity while involving a low level of resistance to deformation under the effect of heat.
In consideration of that state of the art the object of the present invention is to simplify a dispensing device for liquid containers of flexible material, in particular for wine containers of bag-in-box systems, in regard to the design configuration thereof, and to enhance their gas-tight sealing integrity. The invention also seeks to provide that the amount of plastic material used is reduced and handleability and cleanability are improved.
In accordance with the invention a tubular housing body is closed at one end by a diaphragm-like front disk and supported therein is a rod-like element which passes therethrough and from which extends a valve tappet for a valve head which is associated with the outlet opening provided laterally in the tubular housing body. The valve tappet and the valve head should advantageously form a shaped or molded unit comprising plastic material which is softer than the housing body or the rod-like elementxe2x80x94for example polyethylenexe2x80x94; the valve tappet is supported on the rod-like element in the region of a pivot location. The rod-like element and the housing body are preferably formed from polypropylene.
In accordance with a further feature of the invention, in the closed position of the valve head, the above-mentioned rod-like element extends substantially parallel to the longitudinal axis of the housing body and can be pivoted therefrom towards the outlet opening, with temporary deformation of the front disk, for which purpose outside the housing body it is advantageously in the form of a kind of press key body, that is to say it affords a pressing surface for a finger or the like. In order to predetermine the pivotal movement of the rod element, formed on the key body in accordance with the invention at the rear thereof is an abutment element which in the closure position is disposed at a spacing relative to a mounting tongue or the like profile element, which projects from the face of the housing body. That helps a user to implement the pivotal movement by means of two fingers.
For that purpose, the mounting tongue can be associated with the peripheral region of the housing body, which is in diametrally opposite relationship to the outlet opening, that is to say, the two gripping fingers pivot the inner portion of the rod element towards the outlet openingxe2x80x94for that purpose the valve head is associated with an edge or tubular outlet portion surrounding the outlet opening at the outside of the housing body and is guided away therefrom.
If the mounting tongue is associated with or formed on the peripheral region of the housing body, which is adjacent to the outlet opening, the two fingers pivot the inner portion of the rod element away from the outlet opening, and for that reason, in this case, the valve head is associated with the edge or tubular outlet portion surrounding the outlet opening at the inside of the housing body, and can be lifted off towards the longitudinal axis of the housing body away from the tubular outlet portion or the like.
Accidental actuation of the valve during transportation or the like is prevented by the key body being connected at the front end to at least one securing tongue portion and by the latter being connected at the other end to the housing body and/or its front disk; the securing tongue portion can advantageously be formed on the one hand on the key body and on the other hand on the front disk in each case by means of at least one molded strip.
It is only after the molded strips have been severed that the key body can be pivoted.
If there is a wish to keep the outlet opening in an opened condition, independently of the hand of the user, attached to or formed on the key body is an at least partially flexible elongate molded portion which extends from the key body and which has a detent body at the end thereof; in the open position of the valve element and when the rod-like element is in an inclined position, the elongated molded portion is pushed into an edge opening of the mounting tongue in such a way that its detent body can be laid on the outside surface of the mounting tongue. The position of the key bodyxe2x80x94and therewith the valvexe2x80x94is established and fixed thereby.
It has proven desirable for the outlet portion which surrounds the outlet opening to be formed out of the housing body at an angle relative to the longitudinal axis of the housing body, preferably at an angle of about 75xc2x0 C. in that way the outlet opening is more easily accessible. If moreover the outlet portion is provided with a male screwthread, a hose can be fixed thereto as a permanent conduit.
At a spacing relative to the outlet opening the housing body is provided with a radial flange collar as an abutment element for an annular body of a push-on flange which can be pushed on to the housing body. The flange is sealingly fixed, for example welded, to the inner container by means of an end annular flange delimiting an opening through the liquid container, and forms the coupling portion thereof for the housing body. The latter and the push-on flange in the position of use are sealingly connected in mutually detent relationship by radially acting retaining pairingsxe2x80x94on the one hand peripheral grooves and on the other hand peripheral beads which can be fitted thereinto.

Dispensing device for a liquid container

Kunststoffwerk and Formenbau Arthur Steiger AG


A pumping unit supplies pumping light to a fiber connecting medium; a light monitoring unit detects light power of multiple-wavelength light; and a control unit controls the pumping light based on light power detected by the light monitoring unit and connecting medium information indicating optical characteristics in the connecting medium. The connecting medium information includes information indicating a fiber type of the fiber connecting medium, information indicating a length of the fiber connecting medium, an average fiber loss coefficient of the fiber connecting medium and an intra-station loss value.

1. Field of the Invention
The present invention relates to a Raman amplifier amplifying multiple-wavelength light, a wavelength multiplex transmission apparatus or a wavelength multiplex transmission system employing it, and a Raman amplifier adjustment method for adjusting the Raman amplifier.
2. According to a wide spread of the Internet, an amount of information to be transmitted via the network increases. Therefore, it is an essential issue to achieve increase in a capacity of the network and a long-distance data transmission system.
As a core technology for achieving long-distance data transmission and large-capacity data transmission, a Raman amplifier has been studied to be put into a practical use. The Raman amplifier is an amplifier which utilizes an optical fiber connecting medium as an amplification medium by supplying pumping light thereto.
In the Raman amplifier, as shown in FIG. 1, when pumping light having a wavelength is supplied to an optical fiber, a Raman gain is generated in a wavelength zone corresponding to the pumping light wavelength. There, difference between the pumping wavelength and the wavelength at which the Raman gain has a peak is approximately 100 nm.
In order to obtain the gain throughout a wide wavelength band, it is necessary to provide pumping light in a plurality of different wavelengths. In an example shown in FIG. 1, pumping light 1 through pumping light 3 having mutually different wavelengths are used. When such pumping light in a plurality of wavelengths is supplied to an optical fiber, a Raman gain is generated for pumping light in each wavelength. In the example shown in FIG. 1, Raman gains 1 through 3 are generated by means of the pumping light 1 through pumping light 3. Accordingly, by appropriately controlling power of each pumping light, it is possible to obtain a substantially flat gain throughout a wide wavelength band.
For this purpose, in the Raman amplifier, normally, light power in input multiple-wavelength light is monitored, and the power of each pumping light supplied is adjusted so that the light power thereof may be kept in a predetermined level. Further, in the Raman amplifier, since ASS (Amplified Spontaneous Scattering) noise is inevitably generated, a function of subtracting the ASS noise component from a received light power value is needed. Thereby, light power of multiple-wavelength light can be detected properly.
Such a Raman amplifier may involve the following problems:
1) The Raman gain depends on optical characteristics of the fiber connecting medium (transmission path) applied. Thereby, due to variation in the optical characteristics in the fiber connecting medium, a desired. Raman gain may not be obtained. As a result, a substantially flat gain may not be obtained, as shown in FIG. 3, for example. For example, even when the pumping light power is adjusted for obtaining a substantially flat gain assuming standard optical characteristics, actually, a non-flat gain such as that shown in FIG. 3 may be obtained in a case where a new data transmission system is built and actual optical characteristics of an actual fiber connecting medium differ from the standard ones.
2) Since the above-mentioned ASS noise is in proportion to the Raman gain, the ASS noise varies when the optical characteristics in the fiber connecting medium vary. Therefore, it is difficult to properly estimate the ASS noise, due to variation in the optical characteristics in the fiber connecting medium. As a result, it becomes not possible to properly detect input power of multiple-wavelength light itself. For example, in a case where the optical characteristics in the fiber connecting medium vary while received light power (sum total of multiple-wavelength light power and noise component) is same, as shown in FIGS. 4A and 4B, power of the multiple-wavelength light itself (power of signal light obtained from excluding the noise component) actually differs. If the power of the multiple-wavelength light cannot be detected accurately, accuracy in detection of 'input interruption' which may occur due to a trouble in an upstream station, a cable break or such, may be degraded accordingly. 'Input interruption' means a state in which multiple-wavelength light cannot be received at the relevant Raman amplifier due to a case such as that mentioned above.
Accompanying the above-described problems, the following negative effects may also appear:
1) At a time of installation of the Raman amplifier, when the optical characteristics in the fiber connecting medium are actually measured, and the output of the pumping light source is adjusted manually according to the thus-obtained characteristics, a very large labor and a long time are required.
2) Since the Raman gain characteristics fluctuate depending on aging of the fiber connecting medium, the ambient temperature or such, the Raman amplifier should be designed to have a margin considering the fluctuation. Accordingly, the efficiency in the Raman amplifier cannot be kept high enough in design.
3) In an optical amplifier having an EDFA (Erbium added fiber amplifier) provided subsequent thereto, a gain in the EDFA is controlled in a condition in which the ASS noise amount includes error. Thereby, quality in data transmission characteristics may be degraded.
The variation in the optical characteristics in the fiber connecting medium occurs mainly due to the following causes:
1) An optical loss may occur due to contamination in a connecting point between optical fibers (for example, between a fiber connecting medium and an intra-station fiber, for example) or a bending loss in the optical fiber. Such optical loss may be controlled less than 0.5 dB in a station building in a good condition, while it may amount to more than 2 dB in a station building in a bad condition.
2) Fabrication variation may occur in characteristics (loss coefficient, effective cross-sectional area or such) of the fiber connecting medium itself. Especially, influence by the loss coefficient is serious. For example, the loss coefficient of an optical fiver in a good condition is controlled less than 0.21 dB/km while the same in a bad condition may amount to more than 0.25 dB/km. Accordingly, assuming that the length of a fiber connecting medium is 50 km for example, a variation of more than 2 dB may occur in the bad condition.
3) Generally speaking, a fiber connecting medium is produced by splicing a plurality of optical fibers for every kilometers. A loss inevitably occurs at each splicing point. Such a loss in each splicing point is less than 0.1 dB in a better condition, while it may amount to more than 0.5 dB in a worse condition. In this connection, it is noted that intervals of splicing points and the number of splicing points provided between adjacent stations depend on a particular network system.
4) The ambient temperature or aging of the relevant optical fiber influences the optical characteristics in the fiber connecting medium as mentioned above.
Generally speaking, a bender which manufactures the optical amplifier (Raman amplifier) is different from a bender which manufactures and installs the fiber connecting medium applied thereto. Therefore, the bender of the optical amplifier cannot directly manage the optical characteristics of the fiber connecting medium. Accordingly, it is not possible to reduce the above-mentioned issue concerning 'variation in the optical characteristics in the fiber connecting medium'.
Japanese Laid-open Patent Application No. 2002-296145 (especially, FIG. 1, and paragraphs 0028 through 0040) (parent document #1) discloses an art directed to solving these problems. An apparatus disclosed in this document includes an OTDR (optical time domain reflectometry) measuring function, and, with the use of this function, optical characteristics in a fiber connecting medium are measured. Then, based on the measured optical characteristics, a Raman gain is calculated. However, when the OTDR measuring function is thus provided in the optical amplifier, the optical amplifier should have its size increased, and also, have the costs increased, accordingly.
As such a Raman amplifier, distributed Raman amplification (DRA) modules each including one or a plurality of pumping light sources utilize Raman amplification effect. According to the Raman amplification effect, as a result of pumping light (at high intensity, i.e., more than 100 mW) being input to an optical fiber connecting medium made of silica or such by means of the DRA module, the optical fiber itself acts as an amplification medium.
A gain of the DRA module depends on the pumping light amount input to the optical fiber connecting medium, and therefore, the DRA module should be controlled, in the pumping light amount, according to a signal light level monitored, in order to obtain the signal light at a desired level of gain (output).
However, when pumping light having high intensity is input to the optical fiber connecting medium, while signal light is amplified according to the Raman amplification effect thereof, the above-mentioned ASS light is also generated, which acts as signal noise. A light receiving device (made of a photodetector or such) which monitors the signal light receives not only the signal light itself but also the ASS light, and also, it receives so-called ASE light inevitably (see FIGS. 26 and 27). Therefore, in order to perform control such as to obtain the signal light at a desired constant level accurately, it is necessary to calculate and estimate the ASS light amount generated as a result of the pumping light being input to the optical fiber connecting medium. Especially in a case where the number of wavelengths multiplexed is small, or the signal light level is low, a ratio of the ASS light amount is large with respect to the signal light level, and thus, it is necessary to estimate the ASS light amount more accurately. International Patent Publication No. WO02/019023 (patent document #5) discloses a method for accurately estimating the ASS light amount in which predetermined pumping light is input to a specific fiber, and, while the pumping light amount is monitored in a DRA module, the ASS light amount generated in the fiber is measured. Thereby, a relational expression between the pumping light amount and the ASS light amount is derived, and therewith, the ASS light generation amount is estimated from any particular pumping light amount to supply.
However, as mentioned above, even when a same type of fiber is applied, variation exists in a loss coefficient and an effective core cross-sectional area which influence a Raman gain and an ASS light generation amount, and also, variation exists in an optical loss (local loss) occurring between the DRA module and the fiber connecting medium due to conditions of the connecting medium (transmission line) applied. Therefore, in a case where an actual connecting medium has conditions different from those for which the above-mentioned relational expression was derived, error occurs between the actual ASS light generation amount and the ASS light estimation amount obtained in the optical amplifier itself. Thereby, the accuracy in estimation of ASS light amount may be degraded actually.
Thus, such a factor degrading the ASS light generation amount estimation accuracy may obstruct achievement of a desired signal light constant control result even when signal light constant control is performed for obtaining a desired signal light level. For example, in a case where an ASS estimation amount is smaller than an actual one, control may be made based on erroneous recognition as if a signal light level reaches a desired one even when the actual signal light level is smaller than the desired one (see FIG. 28). Especially in a case of a multi-stage optical transmission apparatus in which many optical amplifiers each including the DRA module are connected in series, degradation in ASE correction accuracy due to ASS light generation amount estimation error may obstruct proper ASE correction in a downstream station, which may result in degradation in a signal-to-noise ratio at a signal receiving station (OSNR).
Further, generally speaking, a DRA module has very large power, and thus, there is dangerousness due to leakage of the pumping light from a fiber terminal end. Therefore, for the purpose of safety, a function of shutdown (forcible output reduction/elimination) of pumping light sources in the DRA module is provided. Specifically, for example, occasion of connector opening, fiber break or such is regarded as an event of 'input interruption' of signal light detected by means of the light receiving device in the DRA module, and it is used as a trigger for the above-mentioned shutdown. However, in a case where such a method is applied, when a threshold light level for determining the input interruption is low, there is a possibility of remarkable degradation in the input interruption accuracy or function, which results in erroneous detection or erroneous non-detection. In a case where input interruption erroneous detection occurs, the pumping light in the DRA module is forcibly turned off and thus, the function of the optical amplifier is turned off although an actual state is a state in which the optical communication apparatus can operate normally. In such a case, a transmission error alarm is generated in a downstream transmission apparatus, and thus, the data transmission quality may be remarkably degraded. On the other hand, in a case where even when connector opening or fiber break actually occurs in an upstream connecting medium, this matter is not detected in the DRA module due to erroneous determination (input interruption non-detection), the above-mentioned shutdown trigger is not applied, and thus, a dangerous state may occur due to pumping light leakage from the fiber terminal end in the DRA module as mentioned above.

Raman amplifier and raman amplifier adjustment method


The invention discloses a composition and method of absorbing and/or detecting the presence of ignitable liquids. The composition includes a hydrophobic polymer, a hydrophobic long-chain carboxylic acid and, optionally, a hydrophobic solvent indicator dye and a hydrophobic white metallic oxide. The composition may be applied to an area suspected of containing an ignitable liquid and allowed to remain on the area for a time period sufficient to react with the ignitable liquid. If an ignitable liquid is present, the composition will form an aggregate by agglomeration with the ignitable liquid.

Arson is a costly public safety problem. The cost of fire damage in the United States is several billions of dollars per year. Arson, the willful and malicious burning of property, accounts for approximately one third of these costs.
The most effective way to try and reduce the cost and damage caused by fire is through the use of effective fire investigation to find and prosecute those responsible. However, the devastation, charred debris, collapsed structures, water-soaked ashes, weather conditions, together with the smoke and stench makes arson extremely difficult to detect and prove.
The basic role of a fire investigator is twofold: first to determine the origin of the fire, and second to examine the site of the fire to determine what caused the fire to start. Once the origin of the fire is found, examination of the debris is necessary to determine the fire""s cause. A major objective in any suspected case of arson is to search for, locate, sample and analyze residual accelerants, which are usually in the form of ignitable liquids.
Most purposefully caused fires involve the use of an accelerant to speed the ignition and rate of spread of the fire. The most commonly used accelerants are diesel fuel, mineral spirits, kerosene, gasoline, and turpentine due to their flammability and ready availability. Less commonly used accelerants include alcohols, ketones, and industrial solvents. The amount of accelerant remaining after a fire depends not only on factors such as quantity and type of compound used, but also on the nature of material it is poured on, the elapsed time since the fire, and the severity of the fire.
There are currently several methods for detecting accelerants available. First, physical indicators, such as localized burn patterns to floors and surfaces and overhead damage inconsistent with the naturally available fuel, can be used to detect the presence of accelerants. The primary problem with physical indicators is that they are frequently destroyed during the course of the fire. Further, physical evidence which indicates a hot and intense fire, such as a color change or spalling in concrete, melted aluminum or brass and deformation of steel, are unreliable as indicators of the presence of an accelerant, as many combustible materials tend to burn with the same intensity as accelerants.
Fire investigators often rely upon their own sense of smell to attempt to identify the presence of accelerants. As would be expected, this ability varies greatly amongst investigators since, like most other senses, it can become highly developed through experience, or permanently impaired. In addition, continual smelling of the toxic vapors produced by accelerants cause the sense of smell to become less effective, and lessens the ability of the investigator to discriminate between accelerant vapors.
Sniffer dogs are also used for the detection of accelerants. Dogs have a keener sense of smell than humans, and also have much greater ability to discriminate between target scents. However, the effectiveness of sniffer dogs is entirely dependent on the level of training the dog has been given. Moreover, dogs are sometimes unable to detect odorless fire accelerants, because the accelerant molecule is not aromatic.
Portable hydrocarbon detectors are commonly used in accelerant detection at fire scenes. Hydrocarbon detectors are extremely sensitive and able to separate and detect trace amounts of volatile hydrocarbons. The extreme sensitivity of a hydrocarbon detector is also its biggest drawback, however, since it is associated with a large number of false positives. For instance, a portable hydrocarbon detector can detect hydrocarbons from various materials such as rubber-backed carpet, carpet and tile glue, or burnt plastic, and the results are wrongly interpreted as indicating the presence of an ignitable liquid used as an accelerant.
It is therefore an object of the present invention to provide a more accurate method and means of detecting arson by detecting the presence of ignitable liquids.
It is a further object of the present invention to provide a method and means of absorbing crude oil, petroleum distillates, and solvents to prevent absorption of these substances into the environment.
It is yet another object of the present invention to provide a method and means of detecting and/or absorbing ignitable liquids which is sensitive, yet does not result in a high incidence of false positives.
It is another object of the present invention to provide a method and means of detecting and/or absorbing ignitable liquids which does not rely on the subjective nature of a person or animal""s sense of smell.
It is still another object of the present invention to provide a method and means of detecting and/or absorbing ignitable liquids which is economical and easy to use.
Other objects of the invention will become apparent from the description of the invention which follows.
The present invention relates to the use of a chemical composition for detecting and/or absorbing ignitable liquids using an ignitable liquid absorbent (ILA). The ILA includes a hydrophobic polymer as a primary absorbent and a hydrophobic long-chain carboxylic acid. The ILA may also contain a hydrophobic solvent indicator dye and a hydrophobic white metallic oxide.
The ILA may be applied to an area suspected of containing an ignitable liquid. If the ILA comes in contact with an ignitable liquid, it changes in form from a powder to an aggregate by means of agglomeration. If a hydrophobic solvent indicator dye is included in the ILA, the aggregate also changes color, thereby more precisely indicating the location of an ignitable liquid. Evidence samples taken using the absorbent can then be tested using conventional laboratory procedures, such as gas chromatography or mass spectroscopy to determine the presence of target liquid accelerants or ignitable liquids.
The present invention is based on an improved method and means for detecting ignitable liquids.
Through education, training, and experience, fire investigators are able to investigate a fire scene and, based on burn patterns and other evidence collected from the scene, form an expert opinion as to the origin and cause of the fire. However, on many fire scenes where the fire has been intentionally ignited, the use of an ignitable liquid as a fire accelerant is not always obvious, because it remains only in trace amounts after the fire. The remaining trace amounts of ignitable liquid may also be semi- or fully soluble in water, thereby becoming even further diluted as a result of fire suppression efforts prior to the investigation.
Using the composition of the present invention, even trace amounts of the ignitable liquid used to accelerate the fire can be identified and collected as evidence. Further, fuels that are soluble in water can be separated from the water, identified, and collected as evidence.
The first ingredient in the ignitable liquid absorbent (ILA) of this invention is a hydrophobic polymer powder or micro-fiber. Polymers which meet this definition are capable of absorbing or adsorbing ignitable liquids, such as alcohols, ketones, crude oil, petroleum distillates, or solvents. Ignitable liquids are typically nonpolar, or have limited polarity so as not to strongly hydrogen bond with water molecules. Because the water molecule is highly polar, the majority of ignitable liquids will not form a homogenous solution with water, but will instead form an identifiable two-phase liquid separation. Some ignitable liquids, such as specific alcohols or ketones with the lowest molecular weight of their class, will form a homogenous solution when introduced in water. The ILA of this invention has the capability of absorbing these liquids without absorbing a significant amount of water, thus causing their separation from water.
Hydrophobic polymers for use in this invention are generally composed of long linear carbon chains or cross-linked carbon chains and may have an oxygen, sulfur, nitrogen, or halon molecule substituent. Preferred hydrophobic polymers include polypropylene, polyethylene, polybutylene, polystyrene, polyurethane, polyisocyanurate, polyvinyl acetate, polyvinyl chloride, polyethylene terephthalate, polymerized acrylonitrile butadiene styrene, and hydrophobic zeolites or dendrimers. The most preferred hydrophobic polymer is polypropylene. The hydrophobic polymer should be included in the composition in an amount ranging from about 0.1-99% by weight, with about 60-90% by weight being preferred, and about 70-80% by weight being most preferred.
The next ingredient in the ILA is a long-chain carboxylic acid or derivative thereof that dissolves or softens in ignitable liquids but remains hydrophobic after dissolving. Examples of such compounds include octadecanoic acid (stearic acid), octadecanamide (stearamide), octadecyl acetate, ethyl chloroacetate, and acetyl bromide. The most preferred long-chain carboxylic acid is stearic acid. The long-chain carboxylic acid serves as a primary binder and hydrophobic barrier in the ILA. The long-chain carboxylic acid should be included in the ILA in an amount ranging from about 1-99% by weight, with about 10-40% by weight being preferred, and about 10-25% by weight being most preferred.
The ILA may also include a hydrophobic indicator dye to more precisely ascertain the presence and location of an ignitable liquid. Such dyes are well known in the art and are commonly referred to as xe2x80x9csolvent dyes.xe2x80x9d Several companies, such as Neha-Chem, Max-Pages, Tri Chem Inc., Neomark International Corp. and Chekemcolour Limited, manufacture solvent dyes. Hydrophobic solvent indicator dyes are generally soluble and/or miscible in a wide range of organic solvents, and in synthetic and natural resins. Hydrophobic solvent indicator dyes generally consist of metal complex dyes (e.g. chrome-complex and cobalt-complex), anthraquinone dyes, dye salt, and azo dyes.
Any hydrophobic solvent indicator dye may be used in the ILA of this invention, including Solvent Blue (e.g. #4, 24, 35, 36, 38, 70, 78, 122), Solvent Red (e.g. #8, 23, 24, 25, 49, 52, 109, 111, 122, 130, 132, 135, 146, 149, 168, 169, 179, 196, 197), Vat Red 41, Solvent Violet (e.g. #8, 9, 11, 13, 28, 31, 59, 132), Solvent Blue (e.g. #4, 35, 36, 38, 70, 78, 122), Solvent Black (e.g. #27, 29, 34, 45, 46), Solvent Yellow (e.g. #2, 14, 16, 19, 21, 33, 45, 56, 72, 82, 93, 98, 114, 145, 163, 176), Solvent Orange (e.g. #45, 54, 60, 62, 63, 86), Solvent Green (e.g. #3, 5), and Solvent Brown (e.g. #43). A preferred hydrophobic indicator dye for use in this invention is Solvent Blue (e.g. #36).
The hydrophobic indicator dye serves to indicate when the ILA of this invention comes into contact with an ignitable liquid. The hydrophobic indicator dye should be included in the ILA in an amount ranging from about 1xc3x9710xe2x88x926 to about 99% by weight, with about 0.02 to 3% by weight being preferred, and about 0.03% to 1% by weight being most preferred.
The ILA of this invention also preferably includes a hydrophobic white metallic oxide, which serves as a contrast agent for the hydrophobic solvent indicator dye. Specifically, the hydrophobic white metallic oxide provides a white background to increase the visibility of the dye when it changes color to indicate the presence of an ignitable liquid. Hydrophobic white metallic oxides include aluminum oxide, titanium dioxide, and zinc oxide. Titanium dioxide is preferred. If included in the ILA, the hydrophobic white metallic oxide should be present in a concentration ranging from about 0.1-99% by weight, with about 7-22% by weight being preferred, and about 9-14% by weight being most preferred.
In manufacturing the ILA of this invention, the long-chain carboxylic acid is first heated to a temperature of at least 69.3xc2x0 C. in order to melt, but not boil, the long-chain carboxylic acid. Once melted, the hydrophobic polymer is added and blended to form a homogenous mixture. If included in the ILA, the hydrophobic white metallic oxide should be added at the same time as the hydrophobic polymer. In the alternative, the hydrophobic polymer may be purchased as a mixture with the white metallic oxide, and the combination added all at once to the melted long-chain carboxylic acid.
Once formed, the homogenous mixture is cooled to ambient temperature, and ground to form a fine powder. If included in the ILA, the indicator dye powder is mixed in at this time. The powder preferably has a particle size of less than about 30 microns, with between 5 microns to 25 microns being most preferred. Powders having a larger particle size will work in the invention. However, smaller particle sizes are preferred since they increase the surface area of ILA exposed to the ignitable liquid.
The resulting powdered ILA should be stored in a dry, clean container until ready for use. If it is intended to be used in conjunction with an arson investigation, the ILA is preferably stored in a nylon evidence bag or other non-contaminated container.
In practice, the ILA of this invention may be applied by sprinkling or other means on an area suspected of containing an ignitable liquid. The amount of ILA used for this purpose will vary according to the degree of sensitivity desired in the testing procedure. As a general rule, the ILA may be applied to the testing area in an amount of about 0.5 kilograms/9 square meters.
The ILA should remain on the testing area for an amount of time sufficient for the ILA to react with the ignitable liquid and form an aggregate and/or for an amount of time sufficient to allow the hydrophobic indicator dye to change color. This time frame will vary depending on a number of factors, including the amount of ignitable liquid present, the amount of ILA added, and the temperature of the test site, with the speed of the test increasing proportionately as the temperature increases. For instance, if the conditions of the test site are fairly warm (such as would be the case during summer months), the ILA may react to the presence of ignitable liquid in as little as ten seconds. Even during cooler testing conditions, however, and if an ignitable liquid is present at the test scene, the ILA will typically indicate its presence within fifteen minutes, in levels at least as low as 0.1 ppm, which are not perceptible to the human senses. If the ILA comes into contact with an ignitable liquid, it will not only change in color, but in texture. Specifically, the powdered ILA will change from a powder to an aggregate by agglomeration.
Once the testing is complete, and if desired and/or required by law, samples from the area testing positive for ignitable liquid may be collected and chemically tested in a laboratory or by other conventional means, such as gas chromatography or mass spectroscopy, to specifically identify the types and brands of the ignitable liquids present in the samples.
It is specifically contemplated that the ILA and methods of this invention may be used for the general purpose of detecting the presence of ignitable liquids not only for purposes of arson investigation, but in any situation where it is desired to detect and/or absorb such compounds.
For example, the ILA of this invention can be used as an absorbent for hazardous materials in clean-up methods. Further, the ILA of this invention can be used as a barrier for preventing crude oil, petroleum distillates, and solvents from contacting a shoreline or other environmentally sensitive areas following a spill. The ILA is especially effective for this purpose since, upon reaction with the ignitable liquid, the ILA forms an aggregate by agglomeration which serves as a barrier that does not break apart even upon exposure to external forces such as wave action, high winds, etc. This is in stark contrast to prior art clean-up compositions which merely aggregate to form loosely connected clumps that break apart once exposed to these external forces.
In this respect, the ILA can be delivered to the site of the spill by means of aerial dispersal, from sea level or ground level. In the case of a marine crude oil spill, the ILA preferably includes a brightly-colored indicator dye, such as fluorescent orange, to maximize the potential for tracking the spill from satellite or at sea level. The ILA can be safely used in marine and freshwater environments without presenting an additional environmental hazard.
In addition, the ILA can be mixed with an aggregate, or used alone, and packed around underground fuel storage tanks or delivery lines to prevent and/or minimize fuel leaks from entering the surrounding ground and groundwater. The ILA can also be used to remove specific solvents from surface water, ground water, or municipal water systems. Moreover, the ILA may be used to absorb alcohol from water without the addition of heat, thus reducing the cost of alcohol distillation.
The following examples are offered to illustrate but not limit the invention. Thus, they are presented with the understanding that various formulation modifications as well as method of delivery modifications may be made and still be within the spirit of the invention.

Method and composition for detecting ignitable liquids


Initiator systems of the invention comprise: a complexed initiator comprising at least one of a complex of a complexing agent comprising at least one hydroxide and an initiator or a complex of a complexing agent comprising at least one alkoxide and an initiator; and a decomplexer. The initiator systems are useful for initiating polymerization of at least one monomer to form polymerized compositions. Kits of the invention useful for forming the polymerized compositions comprise a polymerizable composition and an initiator component, wherein the initiator component comprises a complexed initiator of the invention. Bonding compositions can be prepared by mixing the polymerizable composition of the kit with the respective initiator component.

The present invention relates generally to complexes of initiators and complexing agents comprising at least one hydroxide, alkoxide, or mixtures thereof The complexes are useful in initiator systems for polymerization of monomers.
Systems for initiating the polymerization of monomers to make compositions, such as adhesives, are known in the art. U.S. Pat. Nos. 5,106,928, 5,286,821, and 5,310,835 to Skoultchi et al., for example, describe two-part initiator systems for initiating the polymerization of acrylic monomers. The first part of these two-part systems typically includes a stable organoborane amine complex and the second part includes an activator. The activator liberates the organoborane compound by removing the amine group, thereby allowing the organoborane compound to initiate the polymerization process. Activators are also sometimes referred to as liberators or decomplexers.
Common complexes in such systems include complexes of an organoborane and an amine. While such complexes may be useful in many applications, certain problems may arise due to the use of amine complexing agents in such conventional complexes. For example, when the complexes contain a primary amine, adhesives prepared therefrom may be prone to discoloration, such as yellowing. Furthermore, when including reactive diluents, such as aziridine-functional materials described in PCT Publication No. WO 98/17,694, for example, in compositions containing the complexes, the diluents may prematurely react with protic amines (i.e., those amines in which a nitrogen atom is bonded to at least one hydrogen atom) in such complexes, prematurely decomplexing the organoborane initiator. This phenomenon may even be to such an extent as to prematurely initiate polymerization of monomers present with the complexes or to degrade efficacy of the initiators for polymerization of subsequently added monomers.
In light of these potential problems and the desire to provide alternative formulations, further complexes are desirable, particularly for use in initiator systems, such as those used for polymerization of adhesives useful for bonding low surface energy substrates.
Initiator systems of the invention comprise: a complexed initiator comprising at least one of a complex of a complexing agent comprising at least one hydroxide and an initiator and a complex of a complexing agent comprising at least one alkoxide and an initiator; and a decomplexer. Preferably, the initiator comprises an organoborane initiator.
Complexes of organoborane initiators and complexing agents of the invention may be represented by the following general Formula (I):
wherein R1 is an alkyl group having 1 to about 10 carbon atoms. R2 and R3 may be the same or different and are selected from (i.e., they are independently selected from) alkyl groups having 1 to about 10 carbon atoms and phenyl-containing groups. xe2x80x9cCxxe2x80x9d represents a complexing agent of the invention. The value of xe2x80x9cvxe2x80x9d is selected so as to provide an effective ratio of oxygen atoms of the alkoxides and/or hydroxides to boron atoms in the complex.
The initiator systems are useful for initiating polymerization of at least one monomer. To initiate polymerization in such a manner, at least one monomer is provided and then blended with the initiator system. Polymerization of the at least one monomer can be initiated as such.
In one embodiment, the complexed initiator comprises a complexing agent represented by Formula (II):
xe2x80x83((xe2x88x92)Oxe2x80x94R4)nM(m+)xe2x80x83xe2x80x83(II)
wherein each R4 is independently selected from hydrogen or an organic group (e.g., an alkyl or alkylene group); M(m+) represents a countercation (comprising a monovalent cation, such as a Group IA metal (e.g., sodium and potassium) cation or onium, or a multivalent cation, such as a Group IIA metal (e.g., calcium and magnesium) cation); n is an integer greater than zero; and m is an integer greater than zero. Preferably, n and m are equal. Preferably, each R4 is the same in a complexing agent. Particularly preferred complexing agents comprise those having a countercation comprising a cation selected from sodium, potassium, and tetraalkylammoniums.
According to another aspect of the invention, complexing agents of the invention are used as part of a kit. In one embodiment, kits of the invention comprise a polymerizable composition, wherein the polymerizable composition comprises:
at least one polymerizable monomer, and
at least one decomplexer; and
an initiator component, wherein the initiator component comprises:
a complexed initiator comprising at least one of:
a complex of a complexing agent comprising at least one hydroxide and an initiator, and
a complex of a complexing agent comprising at least one alkoxide and an initiator, and
an optional diluent.
A bonding composition can be prepared by mixing the polymerizable composition of the kit with the respective initiator component. The bonding composition can be used, for example, to prepare substrates at least partially coated with the bonding composition and bonded articles comprising a first substrate and a second substrate, with the polymerized bonding composition adhesively bonding the first and second substrates together. The bonding compositions are particularly useful for coating low surface energy substrates.
This invention provides initiator systems capable of initiating polymerization. More specifically, the invention provides xe2x80x9cinitiator systemsxe2x80x9d comprising (1) a complexed initiator (for example, an organoborane hydroxide, an organoborane alkoxide complex, or mixtures or combinations thereof) and (2) a decomplexer.
In one aspect of the invention, the initiator system is part of a multi-part kit. Such kits comprise at least a first part (i.e., a polymerizable composition) and a second part (i.e., an initiator component) for initiating polymerization of the polymerizable composition. Most preferably, for ease of use, the kits comprise only two parts. The two parts of the kit may be readily combined in a convenient, commercially useful, whole number mix ratio of 1:10 or less, more preferably 1:4, 1:3, 1:2 or 1:1, such that they can be easily used with multi-part dispensers. Such dispensers are shown in U.S. Pat. Nos. 4,538,920 and 5,082,147 and are available from ConProTec, Inc. (Salem, N.H.) under the trade designation, MIXPAC. The parts of the kit can be readily mixed to form bonding compositions, which readily polymerize to polymers, for example, adhesives.
The xe2x80x9cpolymerizable compositionxe2x80x9d typically comprises at least one decomplexer and at least one polymerizable monomer.
The xe2x80x9cinitiator componentxe2x80x9d typically comprises at least one complexed initiator (e.g., an organoborane hydroxide complex, an organoborane alkoxide complex, or mixtures or combinations thereof) and an optional diluent. When mixed with the polymerizable composition, the decomplexer in the polymerizable composition liberates the initiator (e.g., organoborane) from the complexing agent (e.g., a complexing agent comprising at least one hydroxide, alkoxide, or mixtures thereof), enabling polymerization of the monomer(s) to be initiated. xe2x80x9cBonding compositionsxe2x80x9d are those compositions resulting from mixing of the polymerizable composition and the initiator component according to one aspect of the invention. The bonding compositions are useful for bonding a wide variety of substrates, including substrates derived from polymers, wood, ceramics, concrete, and metals. The bonding compositions are especially useful for bonding low-surface energy substrates.
xe2x80x9cLow surface energy substratesxe2x80x9d are those that have a surface energy of less than 45 mJ/m2, more typically less than 40 mJ/m2 or less than 35 mJ/m2. Included among such materials are, for example, polyethylene and polypropylene.
Other polymers of higher surface energy that may also be usefully bonded with the compositions of the invention include polycarbonate and polymethylmethacrylate. However, the invention is not so limited; the compositions may be used to bond any suitable substrate, such as those derived from thermoplastics, as well as wood, ceramics, concrete, primed metals, and the like.
xe2x80x9cPolymerized compositionsxe2x80x9d (also referred to as polymers) are those compositions where substantially all of the monomers in the bonding composition are polymerized except for a typically unpolymerized amount as recognizable to one of ordinary skill in the art. Polymerized compositions according to the invention may be used in a wide variety of ways, including, for example, as adhesives, bonding materials, sealants, coatings, and injection molding resins. The polymerized compositions may also be used as matrix resins in conjunction with glass, carbon, and metal fiber mats, such as those used in resin transfer molding operations. The polymerized compositions may further be used as encapsulants and potting compounds, such as in the manufacture of electrical components, printed circuit boards, and the like. Those of ordinary skill in the art will recognize a wide variety of other applications in which the polymerized compositions are useful.
Initiator Component
Complexed Initiator
In general, complexed initiators of the invention are complexes of an initiator and a complexing agent, specifically complexing agent comprising at least one hydroxide, alkoxide, or mixtures thereof A xe2x80x9ccomplexxe2x80x9d is readily understood by one of ordinary skill in the art to be a tightly coordinated salt formed by association of a Lewis acid (e.g., initiator) and a Lewis base (e.g., hydroxide or alkoxide).
Any suitable complexing agent comprising at least one hydroxide, alkoxide, or mixtures or combinations thereof, may be used for the complexing agent, as long as the complexing agent is reactive with the decomplexer (if any) with which it is to be used. Furthermore, the complexing agent should also be capable of forming a complex with the initiator with which it is used.
Any suitable initiator, or combination thereof, may be used in the invention, as long as the initiator is capable of forming a complex with the complexing agent. Furthermore, the initiator should also be capable of initiating polymerization of monomers with which it is to be used.
According to one aspect of the invention, the initiator is as an organoborane. Complexes of organoborane initiators and complexing agents of the invention may be represented by the following general Formula (I):

wherein R1 is an alkyl group having 1 to about 10 carbon atoms. R2 and R3 may be the same or different and are selected from (i.e., they are independently selected from) alkyl groups having 1 to about 10 carbon atoms and phenyl-containing groups. Preferably, R1, R2 and R3 are independently selected from alkyl groups having 1 to about 5 carbon atoms. Accordingly, R1 R2 and R3 may all be different, or more than one of R1, R2 and R3 may be the same. Most preferably, R1, R2 and R3 are the same.
Together, R1, R2 and R3, along with the boron atom (B) to which they are attached, form the initiator. Specific organoborane initiators include, for example, trimethylborane, triethylborane, tri-n-propylborane, triisopropylborane, tri-n-butylborane, triisobutylborane, and tri-sec-butylborane.
xe2x80x9cCxxe2x80x9d in Formula I represents a complexing agent of the invention, which is described further below.
The value of xe2x80x9cvxe2x80x9d is selected so as to provide an effective ratio of oxygen atoms of the alkoxides and/or hydroxides to boron atoms in the complex. The ratio of oxygen atoms of the alkoxides and/or hydroxides to boron atoms in the complex should broadly be about 0.5:1 to about 4:1, preferably about 1:1 to about 2:1, more preferably about 1:1 to about 1.5:1, and most preferably about 1:1.
Complexing Agent
The following terms will hereinafter be used to more particularly describe the complexing agent of the invention:
The terms xe2x80x9cmonovalent organic groupxe2x80x9d and xe2x80x9cmultivalent organic groupxe2x80x9d mean an organic moiety wherein the available valencies are on carbon atoms. Monovalent organic groups have one available valency. Accordingly, multivalent organic groups have more than one available valency.
The xe2x80x9corganic groupsxe2x80x9d can be aliphatic groups or cyclic groups. In the context of the present invention, the term xe2x80x9caliphatic groupxe2x80x9d means a saturated or unsaturated, linear or branched, hydrocarbon group. This term is used to encompass alkylene, alkenylene, alkynylene, alkyl, alkenyl, and alkynyl groups, for example. The term xe2x80x9calkyl groupxe2x80x9d means a monovalent, saturated, linear or branched, hydrocarbon group (e.g., a methyl, ethyl, isopropyl, t-butyl, heptyl, dodecyl, octadecyl, amyl, or 2-ethylhexyl group, and the like). The term xe2x80x9calkylenexe2x80x9d means a multivalent, saturated, linear or branched hydrocarbon group. The term xe2x80x9calkenyl groupxe2x80x9d means a monovalent, unsaturated, linear or branched, hydrocarbon group with one or more carbon-carbon double bonds (e.g., a vinyl group). The term xe2x80x9calkenylenexe2x80x9d means a multivalent, unsaturated, linear or branched, hydrocarbon group with one or more carbon-carbon double bonds. The term xe2x80x9calkynyl groupxe2x80x9d means a monovalent, unsaturated, linear or branched, hydrocarbon group with one or more carbon-carbon triple bonds. The term xe2x80x9calkynylenexe2x80x9d means a multivalent, linear or branched, hydrocarbon group with one or more carbon-carbon triple bonds.
The term xe2x80x9ccyclic groupxe2x80x9d or xe2x80x9ccyclic structurexe2x80x9d means a closed ring hydrocarbon group that is classified as an alicyclic group, aromatic group, or heterocyclic group. The term xe2x80x9calicyclic groupxe2x80x9d means a cyclic hydrocarbon group having properties resembling those of aliphatic groups. The term xe2x80x9caromatic groupxe2x80x9d or xe2x80x9caryl groupxe2x80x9d means a mononuclear aromatic hydrocarbon group or polynuclear aromatic hydrocarbon group.
Organic groups or organic linking groups, as used herein, can include internal (i.e., not terminal) heteroatoms (e.g., O, N, or S atoms), such as in the case of heterocyclic groups, as well as internal functional groups (e.g., carbonyl groups).
Cx in Formula (I) represents a complexing agent comprising at least one hydroxide, alkoxide, or mixtures thereof. Preferably, Cx and complexing agents of the invention are represented by the following Formula (II):
((xe2x88x92)Oxe2x80x94R4)nM(m+)xe2x80x83xe2x80x83(II)
Each R4 is independently selected from hydrogen or an organic group and each of n and m are integers greater than zero.
Each R4 may be hydrogen in a complexing agent or each R4 may be an organic group in a complexing agent. When any R4 is hydrogen, the complexing agent is said to comprise at least one hydroxide. When any R4 is an organic group, the complexing agent is said to comprise at least one alkoxide. Preferred alkoxides are those where R4 is an alkyl group or an alkylene group. The complexing agent may also include a mixture of at least one hydroxide and at least one alkoxide.
Typically, n is 1 or 2 and m is 1 or 2. Preferably, n and m are the same integer, most preferably 1.
In general, the complexing agent is used in the form of a salt. That is, the complexing agent is stabilized by a suitable countercation such that the complexing agent is capable of complexing the initiator. Thus, in Formula II, M(m+) represents a countercation that stabilizes the complexing agent.
Any suitable cation or combinations thereof can be used for countercations of the invention. The cations can be monovalent or multivalent, as indicated by the superscript, xe2x80x9cm+.xe2x80x9d When xe2x80x9cm+xe2x80x9d is 1, the cation is monovalent. For example, monovalent cations of the Group IA metals (e.g., lithium, sodium, and potassium) can be used. Other suitable monovalent cations include oniums, which generally conform to the following Formula (III):
xe2x80x83(R5)z(X(+))xe2x80x83xe2x80x83(III)
Each R5 is independently selected from monovalent organic groups. Accordingly, each R5 in Formula m may be different, or more than one R5 may be the same. In Formula III, z represents an integer greater than one. Typically z is 2, 3, or 4. Typically, X is a Group VA, VIA, or VIIA metalloid (e.g., nitrogen, sulfur, iodine, and phosphorus). Exemplary onium cations include tetraalkylammoniums (e.g., tetramethylammonium and tetrabutylammounium), triphenylsulfonium, diphenyliodonium, and tetrabutylphosphonium.
When xe2x80x9cm+xe2x80x9d is greater than 1, the cation is multivalent. Exemplary multivalent cations include those cations of the Group IIA metals (e.g., calcium and magnesium).
Monovalent cations are preferred. Especially preferred are sodium, potassium, and tetraalkylammoniums.
Certain complexes comprising hydroxides are known in the art. For example, see certain of the chemical structures disclosed in Brown, Herbert C., Hydroboranes, pp. 55-56 (1962). However, the use of such complexes in initiator systems of the invention has not been reported.
Hydroxides and alkoxides provide strong coupling to organoboranes, with the resulting complexes having excellent oxidative stability. Thus, the use of complexing agents comprising at least one hydroxide, alkoxide, or mixtures thereof is particularly beneficial, particularly in initiator systems of the invention.
Advantageously, preferred complexes of the invention are air stable. By xe2x80x9cair stablexe2x80x9d it is meant that, when the complexes are stored in a capped vessel at room temperature (about 20xc2x0 to about 22xc2x0 C.) and under otherwise ambient conditions (i.e., not under a vacuum and not in an inert atmosphere), the complexes remain useful as polymerization initiators for at least about two weeks. Preferably, the complexes may be readily stored under these conditions for many months and up to a year or more.
Air stability of the complex is enhanced when the complex is a crystalline material (i.e., the complex is a solid at room temperature, but has a measurable melting point when measured according to Differential Scanning Calorimetry). However, complexes of the invention are air stable for at least six months even when they are liquids at room temperature. In some embodiments, liquid complexes (i.e., those complexes having a measurable melting point that is lower than room temperature when measured according to Differential Scanning Calorimetry) and solutions of liquid or solid complexes may be preferred because liquids are generally easier to handle and mix at room temperature than are solids. One of ordinary skill in the art is capable of readily determining whether a complex based on selected initiators and complexing agents is a liquid or solid at room temperature.
Particularly preferred xe2x80x9cair stablexe2x80x9d complexes are non-pyrophoric. That is, the complexes do not spontaneously combust or self-ignite. One of ordinary skill in the art is capable of readily determining whether a complex based on selected initiators and complexing agents is non-pyrophoric. For example, the Pyrophoricity Test described in the Examples, infra, is one method of determining whether a complex is pyrophoric.
Exemplary complexing agents useful in the preparation of complexes of the invention include those prepared from the following: sodium hydroxide, tetrabutylammonium hydroxide, sodium methoxide, and tetrabutylammonium methoxide. Exemplary organoboranes useful in the preparation of complexes of the invention include: triethylborane and tributylborane. It should also be noted that blends of different complexes may be used in initiator systems of the invention.
Complexes of the invention may be readily prepared using known techniques. Typically, the complexing agent is combined with the initiator in an inert atmosphere with slow stirring. An exotherm is often observed and cooling of the mixture is therefore recommended. If the ingredients have a high vapor pressure, it is desirable to keep the reaction temperature below about 70xc2x0 C. to 80xc2x0 C. Once the materials have been well mixed, the complex is permitted to cool to room temperature (i.e., about 22xc2x0 C. to about 25xc2x0 C.). No special storage conditions are required although it is preferred that the complex be kept in a capped vessel in a cool, dark location. Advantageously, the complexes can be prepared in the absence of organic solvents that would later have to be removed, although they could be prepared in solvent if so desired.
The resulting complex is employed in an effective amount, which is an amount large enough to permit polymerization to readily occur to obtain a polymer (preferably, an acrylic polymer). According to one aspect of the invention, when the initiator comprises an organoborane, an effective amount of the organoborane complex is an amount that provides about 0.01 weight % boron to about 1.5 weight % boron, more preferably about 0.01 weight % boron to about 0.60 weight % boron, most preferably about 0.02 weight % boron to about 0.50 weight % boron, based on the total weight of the bonding composition, less the weight of fillers, non-reactive diluents, and other non-reactive components. If the amount of organoborane complex is too low, resulting polymerization may be incomplete or, in the case of adhesives, the resulting composition may have poor adhesion.
On the other hand, if the amount of organoborane complex is too high, then polymerization may proceed too rapidly to allow for effective mixing and use of the resulting composition. Large amounts of the complex could also lead to the generation of large volumes of borane, which in the case of an adhesive, may weaken the bondline when used for bonding substrate(s). The useful rate of polymerization will depend in part on the method of applying the composition to a substrate. Thus, a faster rate of polymerization may be accommodated by using a high-speed, automated industrial adhesive applicator rather than by applying the composition with a hand applicator or by manually mixing the composition.
Diluent
The initiator component may also contain any suitable diluent, or combination thereof The diluent may be reactive or nonreactive with monomers used in the polymerizable composition.
Preferably, the diluent is inert toward the complexing agent. That is, preferably the diluent is essentially free of moieties that are reactive with the complexing agent (i.e., moieties that are susceptible to being esterified by or hydrolyzed by the complexing agent) such that the complexing agent is incapable of complexing the initiator or such that the diluent is chemically modified in such a way that desired properties of the composition are affected.
Nonreactive diluents include plasticizers well known to those of ordinary skill in the art. Reactive diluents include, for example, aziridine-functional materials and maleate-functional materials. For example, such reactive diluents are described in PCT Publication No. WO 98/17,694 and U.S. application Ser. No. 09/272,152, entitled xe2x80x9cOrganoborane Amine Complex Initiator Systems and Polymerizable Compositions Made Therewith, assigned to the assignee of the present invention.
An xe2x80x9caziridine-functional materialxe2x80x9d refers to an organic compound having at least one aziridine ring or group,
the carbon atom(s) of which may optionally be substituted by short chain groups (e.g., groups having 1 to about 10 carbon atoms, preferably methyl, ethyl or propyl), so as to form, for example, methyl, ethyl or propyl aziridine moieties.
Examples of useful, commercially available polyaziridines include those available under the following trade designations: CROSSLINKER CX-100 (from Zeneca Resins; Wilmington, Mass.), XAMA-2 (from EIT, Inc.; Lake Wylie, S.C.); XAMA-7 (from EIT, Inc.; Lake Wylie, S.C.), and MAPO (tris [1-(2-methyl) aziridinyl] phosphine oxide (from Aceto Chemical Corporation; Flushing, N.Y.).
Quite advantageously, when used, the complex is carried by (e.g., dissolved in or diluted by) the diluent or a blend of two or more different diluents in the initiator component. Generally, the diluent should not be reactive toward the complex and functions as an extender for the complex. Also advantageously, the diluent may generally increase the spontaneous combustion temperature of the initiator component, increasing the non-pyrophoric characteristics of the initiator component.
The diluent should be generally soluble in monomers included in the polymerizable composition, such that the parts of the kit can be readily mixed. By xe2x80x9csolublexe2x80x9d is meant that no evidence of gross phase separation at room temperature (i.e., about 22xc2x0 C. to about 25xc2x0 C.) is visible to the unaided eye. Similarly, the complex should also be soluble in the diluent, although slightly warming a mixture of the complex and the diluent may be helpful in forming a solution of the two at room temperature (i.e., about 22xc2x0 C. to about 25xc2x0 C.). Accordingly, preferably, if used, the diluent is a liquid at or near room temperature (i.e., within about 10xc2x0 C. of room temperature) or forms a liquid solution with the complex at or near room temperature.
The diluent is used in an effective amount. Generally, this is an amount of not more than about 50 weight %, preferably not more than about 25 weight %, more preferably not more than about 10 weight %, based on the total weight of the bonding composition. However, substantial amounts (e.g., more than about 15 weight %, sometimes more than about 40 weight %) of the complex may be dissolved in the diluent, which facilitates the provision of multi-part kits that can be combined in a commercially useful mix ratio.
Polymerizable Composition
Decomplexer
The term xe2x80x9cdecomplexerxe2x80x9d means a compound capable of liberating the initiator (e.g., organoborane) from its complexing agent, thereby enabling initiation of the polymerization process. Decomplexers are also sometimes referred to as xe2x80x9cactivatorsxe2x80x9d or xe2x80x9cliberators.xe2x80x9d As used herein, each of these terms has the same meaning.
Any suitable decomplexer, or combinations thereof, can be used, such as isocyanates, acids, acid chlorides, sulfonyl chlorides, anhydrides, compounds capable of liberating any of the foregoing when combined with the initiator component, and mixtures thereof. Examples of suitable acids include Lewis acids and Brxc3x6nsted acids. Particularly suitable decomplexers include lower molecular weight carboxylic acid decomplexers described by Skoultchi et al. (U.S. Pat. Nos. 5,310,835 and 5,106,928), sulfonyl chlorides and acid chlorides of Fujisawa, Imai, and Mashuhara (Reports of the Institute for Medical and Dental Engineering, vol. 3, p. 64 (1969)), bireactive decomplexers comprising isocyanate groups described by Deviny (PCT Publication No. WO97/07,171), anhydride decomplexers described by Deviny (PCT Publication No. WO97/17,383), carboxylic acid decomplexers described by Deviny et al. (PCT Application No. US98/12,296, filed Jun. 12, 1998 and entitled xe2x80x9cInitiator Systems and Adhesive Compositions Made Therewithxe2x80x9d), and mixtures thereof All of these publications are incorporated herein by reference.
The decomplexer is employed in an effective amount (i.e., an amount effective to promote polymerization by liberating the initiator from its complexing agent, but without materially adversely affecting desired properties of the ultimate polymerized composition). As recognizable to one of ordinary skill in the art, too much of the decomplexer may cause polymerization to proceed too quickly and, in the case of adhesives, the resulting materials may demonstrate inadequate adhesion to low energy surfaces. However, if too little decomplexer is used, the rate of polymerization may be too slow and the resulting polymers may not be of adequate molecular weight for certain applications. A reduced amount of decomplexer may be helpful in slowing the rate of polymerization if it is otherwise too fast. Thus, within these parameters, the decomplexer is typically provided in an amount such that the ratio of hydroxide- or alkoxide-reactive groups in the decomplexer(s) (e.g., acid groups or anhydride groups) to hydroxide and alkoxide groups in the complexing agent(s) is in the range of 0.5:1.0 to 3.0:1.0. For better performance, preferably the ratio of hydroxide- or alkoxide-reactive groups in the decomplexer(s) to hydroxide and alkoxide groups in the complexing agent(s) is in the range of 0.5:1.0 to 1.0:1.0, preferably about 1.0:1.0.
Monomers
The initiator system of the invention can be used to initiate the polymerization of any suitable monomer(s). Broadly, the polymerizable composition includes at least one ethylenically unsaturated monomer capable of free radical polymerization. Numerous compounds containing ethylenic unsaturation can be used in the polymerizable composition. Preferably, the composition includes at least one (meth)acrylic monomer, most preferably a methacrylic monomer. Particularly preferred are (meth)acrylic acid derivatives, such as those including esters and/or acid amides. Suitable are, for example, the (meth)acrylic esters of monohydric alcohols, particularly alkanols having from 1 to 12 carbon atoms, such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, and ethylhexyl (meth)acrylate; the (meth)acrylic acid esters of polyhydric alcohols, such as ethylene glycol, diethylene glycol, polyethylene glycol, and trimethylol propane; the di- and mono(meth)acrylic acid esters of glycerin; the di(meth)acrylic acid esters of triethylene glycol and tetraethylene glycol; the di(meth)acrylic acid esters of dipropylene glycol, tripropylene glycol, tetrapropylene glycol and pentapropylene glycol; and the di(meth)acrylic esters of ethoxylated or propoxylated diphenylolpropane.
Basically suitable are also polymerizable monomers, such as vinyl acetate; vinyl halides, such as vinyl chloride, vinyl fluoride, vinyl bromide; styrene; and divinyl-benzene. These compounds, however, are generally used only in subordinate amounts in the polymerizable compositions.
Further suitable are acid amides, such as: acrylamide; N-methyl acrylamide; N-methyl methacrylamide; N,N-dimethyl acrylamide; N,N-dimethyl methacrylamide; N-ethyl methacrylamide; N,N-diethyl acrylamide; N,N-diethyl methacrylamide; N-isopropyl acrylamide; N-butyl acrylamide; N-butyl methacrylamide; N-t-butyl acrylamide; N,N-dibutyl methacrylamide; N-phenyl acrylamide; N-(acryloyl)morpholine; N-(acryloyl)piperidine; N-(methacryloyl)piperidine; N-(1,1-dimethyl-3-oxobutyl)-acrylamide; N-1,3,3-tetramethylbutyl acrylamide; dimethylene-bis-(meth)acrylamide; tetramethylene-bis-(meth)acrylamide; trimethylhexamethylene-bis-(meth)acrylamide; tri(meth)acryloyldiethylenetriamine; and similar compounds.
In general, the emphasis is on monomers with one or two olefinic double bonds in the molecule, preferably one olefinic double bond. The additional use of higher unsaturated components is not excluded, but it must be kept in mind that their presence can lead to embrittling of the polymerized compositions.
Additives
Bonding compositions of the present invention may also comprise further optional additives. Generally, such additives are present in the polymerizable composition of the kit. Thus, the polymerizable composition may further comprise a variety of optional additives.
One particularly useful additive is a thickener, such as medium (about 40,000) molecular weight polybutyl methacrylate that may generally be incorporated in an amount of up to about 50 weight %, based on the total weight of the polymerizable composition. Thickeners may be employed to increase the viscosity of the resulting bonding composition to a more easily applied viscous syrup-like consistency.
Another particularly useful additive is an elastomeric material. These materials can improve the fracture toughness of bonding compositions made therewith, which can be beneficial when, for example, bonding stiff, high yield strength materials (e.g., metal substrates that do not mechanically absorb energy as easily as other materials, such as flexible polymeric substrates). Such additives can generally be incorporated in an amount of up to about 50% by weight, based on the total weight of the polymerizable composition.
Core-shell polymers can also be added to the polymerizable composition to modify spreading and flow properties of the bonding composition. These enhanced properties may be manifested by a reduced tendency for the bonding composition to leave an undesirable xe2x80x9cstringxe2x80x9d upon dispensing from a syringe-type applicator, or sag or slump after having been applied to a vertical surface. Accordingly, use of more than about 20% by weight, based on total weight of the polymerizable composition, of a core-shell polymer additive may be desirable for achieving improved sag-slump resistance. Core-shell polymers can also improve the fracture toughness of bonding compositions made therewith, which can be beneficial when, for example, bonding stiff, high yield strength materials (e.g., metal substrates that do not mechanically absorb energy as easily as other materials, such as flexible polymeric substrates).
Small amounts of inhibitors, such as hydroquinone monomethyl ether may be used in the polymerizable compositions, for example, to prevent or reduce degradation of the monomers during storage. Inhibitors may be added in an amount that does not materially affect the rate of polymerization or the ultimate properties of polymers made therewith. Accordingly, inhibitors are generally useful in amounts of about 100-10,000 ppm based on the total weight of the monomers in the polymerizable composition.
Other possible additives include non-reactive colorants, fillers (e.g., carbon black, hollow glass/ceramic beads, silica, titanium dioxide, solid glass/ceramic spheres, and chalk), and the like. The various optional additives are employed in any amount, but generally amounts that do not significantly adversely affect the polymerization process or the desired properties of polymers made therewith.
Bonding Compositions
The parts of the kits (i.e., the polymerizable composition and the initiator component) are blended as would normally be done when working with such materials. The initiator component is added to the polymerizable composition shortly before it is desired to use the bonding composition.
Once the parts of the kit have been combined to form a bonding composition, the composition should be used quickly, as the useful pot life may be short depending upon the monomers, the amount of the initiator component, the temperature at which the bonding is to be performed, the presence or absence of crosslinking agents, and whether a diluent is used. Preferably, to improve bonding, it is desirable to keep the initial bonding temperature below about 40xc2x0 C., preferably below 30xc2x0 C., and most preferably below about 25xc2x0 C. Accordingly, the bonding process can be carried out at room temperature (i.e., about 22xc2x0 C. to about 25xc2x0 C.).
The bonding composition is applied to one or both substrates to be bonded and then the substrates are joined together with pressure to force excess bonding composition out of the bond line. This also has the advantage of displacing bonding composition that has been exposed to air and that may have begun to oxidize. In general, the bonds should be made shortly after the bonding composition has been applied to the substrate(s), preferably within about 10 minutes. The typical bond line thickness is about 0.1 to 0.3 millimeters.
The bonds may cure (i.e., polymerize) to a reasonable green strength, i.e., to permit handling of such bonded articles within about 2-3 hours. Full bond strength will generally be reached in about 24 hours under ambient conditions. However, post-curing with heat may be used, if desired.
In one preferred embodiment, the bonding compositions are coated on a low surface energy substrate. In another preferred embodiment, bonded articles comprise a first substrate and a second substrate (preferably at least one of which is a low surface energy polymeric material) adhesively bonded together by a layer of a bonding composition according to the invention.
The invention will be more fully appreciated with reference to the following nonlimiting examples. These examples are merely for illustrative purposes only and are not meant to be limiting on the scope of the appended claims. All parts, percentages, ratios, etc. in the examples and the rest of the specification are by weight unless indicated otherwise.

Initiator/hydroxide and initiator/alkoxide complexes, systems comprising the complexes, and polymerized compositions made therewith


An article includes a display layer having an outward facing surface and an inward facing surface. The display layer includes a light-emitting device that generates heat and light during use. A thermal transport layer may be secured to the display layer. The thermal transport layer may include a thermally conductive material that can transport heat generated by the light-emitting device away from the light-emitting device.

1. Technical Field
The invention includes embodiments that relate to an article that has a thermal transport layer. The invention includes embodiments of making and of using the article.
2. Discussion of Art
Light-emitting devices ("LEDs") are inorganic chips that can be used as light sources. Some LEDs may be used in electronic displays, as visual traffic control systems, and in general lighting, automotive, and industrial applications.
At present, heat dissipation is an obstacle faced by commercial LEDs, especially in applications that involve the use of LEDs as light sources. LED's useful lifetime and its emitted color or wavelength may be changed in response to an increase in operating temperature. A portion of the current that is applied to the electrodes is converted into thermal energy rather than into light. To maintain the light source at an acceptable operating temperature and to achieve an adequate usage lifetime and to provide constant luminous flux at certain wavelength, such an illumination system may be equipped with a heat removal system.
Some LED-containing systems have thermal management systems. Although partial thermal management can be done by carefully designing LED device, control junction temperature, and forward current, the thermal management system may also include new integration method to effectively dissipate heat energy by employing additional coating layers, microfluidic channels, and packaging method. Usually, a heat sink in communication with a substrate on which the LED is mounted is a simple thermal management solution. The heat sink may dissipate heat with a fan or a piezoelectric jet actuator. While this approach may dissipate some of the heat generated by the LED, it may increase the size and/or footprint of the module. The fan or piezoelectric device may generate noise.
It may be desirable to have a light-emitting article, device or system having a structure, property or characteristic that differs from those currently available. It may be desirable to have a method of making or using the light-emitting article that differs from currently available methods.


A guide (1) for assessing the general health of the oral cavity comprises at least one indicator (8), characterised in that the indicator (8) is capable of being compared with gums to provide an indication of the general state of the health of the gums.

1. Field of the Invention
The present invention relates to a guide for assessing the general state of health of the gums. It also relates to the use of a guide and to a kit of parts comprising a guide and a oral composition.
2. The Related Art
Dentifrices which provide a whitening benefit are well known in the art. Typically, such dentifrices comprise abrasive agents or bleaches which provide this whitening effect. The concept of a whitening dentifrice is an attractive one for consumers who have stained teeth and wish to improve the cosmetic appearance of the teeth.
Unfortunately, it is difficult to assess the whitening capability of such dentifrices and, to this end, some whitening dentifrices are sold with a shade guide which allows the user to assess the whitening effect of the dentifrice.
Dentifrices which provide a gum health benefit are also known in the prior art. For example, our co-pending application WO 99/59536 describes a dentifrice which is capable of improving the permeability barrier of the gums, thereby reducing the risk of bacterial infection.
Unfortunately, the general state of the gums is not readily apparent to the consumer. Bleeding of the gums can be a signal to the consumer that the gums are not in the proper condition, but while bleeding occurs often during brushing, with or without the accompaniment of pain it does not always occur when the gums are not in prime condition, so the consumer does not get a signal of the gums not being in prime condition.
Accordingly, it is an object of this invention to provide a means for assessing the general state of health of the gums. In particular, there is provided a means for assessing the improvement of the general state of health of the gums through the use of a dentifrice which provides a gum health benefit.
Accordingly, the present invention provides a guide for assessing the general health of the oral cavity comprising at least one indicator, characterised in that the indicator is capable, on comparison with gums, to provide an indication of the general state of the health of the gums.
Preferably, the indicator comprises a colour indication which corresponds to a particular state of health of the gums. For example, the indicator may be coloured pale pink to correspond with the colour of gums in a good state of health; dark red to correspond with the colour of gums in a poor state of health; or somewhere in the middle corresponding with the colour of gums in an intermediate state.
The indicator may also comprise a means for enabling simultaneous in situ comparison between the gums and the indicator. For example, it may comprise one or more regions of coloured indication and one or more apertures through which the gums may be visualised and compared to the colour indication. The means may equally be the edge of the indicator.
In a preferred embodiment the guide comprises more than one indicator so that change in the state of health of the gums may be monitored. For example, the guide may comprise six indicators differently shaded to correspond to six varying degrees of good/bad gum health. The various indicators may be provided with a tenet, indicating the degree of the gum health.
A guide comprising a plurality of such indicators may present the indicators in a graduated form, i.e. they may be presented in an order from pale pink, through to dark red, corresponding to good to poor health of the gums.
It is envisaged that several guides may be available which provide differently shaded indicators to represent the differing shades of healthy gums, which exist between different racial groups. However, it is understood that the indication of gum disease is the same in such groups, i.e. an increase in redness.
A guide comprising a plurality of indicators may consist of a single entity with several indicators graphically displayed on a same surface. It may equally comprise a plurality of separate indicators, which may or may not be linked in a graduated or ungraduated fashion. For example, they may be linked through a ring or a pivot.
The guide according to the invention may also comprise a handle allowing the user to self-assess the state of gum health more easily.
Another feature of the present invention is a guide comprising a lip retractor. Such a retractor enables the user to hold back the gums and compare the indicators with the gums. A preferred retractor will comprise part of the unitary structure of the guide.
In a more preferred embodiment the lip retractor is a temporary feature capable of being formed and removed through the use of the guide. For example, the guide has a lip retractor region and a guide region separated by a fold. Both are maintained in the nominal plane of the guide. When the guide is in use it is bent slightly and the lip retractor emerges from the nominal plane of the guide and becomes capable of holding the lips back from the gums and enabling use of the device.
Preferably the lip retractor provides strong enough support to hold back the lip to enable use of the guide. While the lip retractor may be separated from the remainder of the guide by way of a straight line fold it is preferred that the fold be curved thereby providing a greater support to the lip.
In a further embodiment the guide also comprises a dentition graphic. This provides a more accurate comparison between the gums and the indicators since it is the region of the gums between the teeth which are most susceptible to disease and the presence of white teeth can easily affect the judgment of the user. Accordingly, the graphic may comprise a display of teeth with apertures provided at the interdental regions to allow the user to assess the health of the gums between the teeth.
In an alternative aspect, the invention provides for the use of a guide according to the invention for the assessment of gum health.
The present invention also provides a kit of parts comprising a guide according to the invention and an oral care composition. Such a kit of parts may comprise the guide and the oral composition packaging attached to one another. Such attachment may be permanent, i.e. the guide is part of the external dentifrice packaging (tube or external packaging) or frangible. The oral composition may be any such composition commonly available commercially, e.g. toothpaste, chewing gum, mouthwash, etc.

Unilever Home and Personal Care USA, division of Conopco, Inc.