A buried pipeline construction laser alignment survey platform mountable on manhole sections. The platform has a platform deck and two opposing sets of foldable handrail mounted on the perimeter of the platform deck which are inter-connected by safety chains to complete a safety perimeter. A manhole access in the platform deck has a slideable access cover providing for a closed set-up position, an open access position, and a partially open laser alignment position. One or more sets of anchor pedestals on the bottom of the platform deck provide for securing the platform to manhole sections of one or more diameters.

This invention is in the field of pipeline construction safety devices and in particular the field of pipeline alignment instrumentation platforms for underground pipeline construction.
The construction of underground pipelines, and in particular the construction of pipelines for the non-pressurized, gravity flow of wastewater with suspended solids, such as sanitary sewers and storm sewers, requires tight alignment and slope control. Such pipelines are typically constructed with a uniform pipe diameter, uniform slope and uniform alignment between manholes, with slope changes and alignment changes occurring at manholes only. The manholes are used for access for inspection, maintenance and cleaning of the pipeline. The uniform slope and alignment between manholes provides for the free flow of the waste water with the solids remaining in suspension and not settling out in the pipeline.
Modern construction techniques for such pipelines utilize a construction laser which emits a pinpoint laser beam on a selected alignment and slope for alignment and slope control as the pipeline is laid. The laser is simply mounted in the bottom of the manhole from which the next segment of pipeline is to be constructed. The laser must be adjusted to emit the laser beam on the alignment and with the slope desired for the construction of the next segment of pipeline which connects to the manhole. The horizontal alignment of the laser beam must be set based on reference to survey markers in place on the surface of the ground. While the construction lasers are self-leveling and therefore provide for simply dialing in the desired slope, the alignment of the laser must be surveyed in by reference to survey markers on the surface. The most commonly used method for aligning the laser is to position a surveying instrument known as a transit directly over the laser with the transit being above the surface of the ground with the survey markers in view. The transit can then be set on the proper alignment for the pipeline. With the pipeline trench dug away from the manhole a few feet thereby allowing the laser beam to be directed roughly in the direction of the desired pipeline alignment, the transit is rotated vertically from the desired alignment and the laser beam alignment is adjusted to match the alignment established by the transit. Thereafter, depending upon the soil conditions, the alignment can be checked as the pipe sections are laid and minor adjustments can be made to the laser alignment as the pipeline construction proceeds further away from the manhole. This can continue only so long as the pipe trench is not back filled as trench back filling will obstruct the view of the laser beam through the transit.
The manholes for sanitary sewer and storm sewer lines are generally constructed from pre-formed circular manhole sections which have an inside diameter of 4 feet, 5 feet or more. These manhole sections, which are usually several feet in height are stacked one upon the other on top of a manhole base. The number of manhole sections is dependent upon the depth of the pipeline at the manhole location. On top of the circular manhole sections, a manhole cone narrows the diameter of the manhole down to 2 xc2xd or 3 feet typically. On top of the cone, manhole rings are used to bring the manhole to the desired finish elevation, where the manhole cover is installed.
During the pipeline construction, typically the manhole sections are placed for a manhole up to the level where the cone would be installed. At this point, the transit that is used to align the laser for the next section of pipe is perched on tope of the manhole sections. This is accomplished by spreading the legs of the transit tripod placing them on top of the top manhole section, or placing a board or some other standing surface on top of the top manhole section, leaving an opening for the proper positioning of the transit over the laser. The transit operator is standing on some board on top of the manhole section at great safety risk to himself and others including particularly the workmen inside the manhole to adjust the laser.
An apparatus is needed that will improve efficiency and safety of the construction laser alignment procedure. Despite the inefficiency and obvious safety deficiencies of commonly used procedures, Applicant has found no prior art devices that are designed to address this need. U.S. Pat. No. 5,787,955 and U.S. Pat. No. 5,265,974 to Dargie disclose a safety net for a ground level hatch frame opening. U.S. Pat. No. 4,960,150 discloses a safety cover movable deck on tracks and rollers.
The objective of the present invention is to provide a movable platform which is mountable on the top of a manhole pipe section, providing a safer working surface for workmen for accessing the manhole to set up a pipeline construction laser and for setting up and operating surveying instruments for aligning the construction laser with the desired pipeline alignment.
The present invention is a safety platform for which a preferred embodiment comprises a platform deck, one set of four internal anchor pedestals for anchoring to the inside wall of a small diameter manhole section, another set of four external anchor pedestals for anchoring to the outside wall of a larger diameter manhole section, two opposing pairs of folding handrails with handrail anchor brackets securing the handrail sections to the platform deck, and four sets of safety barrier chains. For preferred embodiments, the platform deck is constructed of grating trimmed with structural angle. However, the platform deck can be constructed of plate material. Grating or plate material can be metallic, such as steel or aluminum, or non-metallic, such as fiberglass. The platform deck has an access opening which is likewise trimmed with structural angle to provide smooth edges for persons using the access opening. The access opening is positioned in the platform deck such that when the platform is positioned on the manhole the access opening outside edge is over the manhole inside wall and the manhole rungs, if there are any. This promotes easy access to the manhole from the platform deck and easy exit from the manhole to the platform deck. A pair of access cover rails is attached to the platform deck bottom, the access cover rail length typically being approximately twice the width of the access opening to allow for the access opening cover to be slid completely under the platform deck to an access position which provides for the access opening to be completely opened. Rail stop plates on each ends of the access cover rails confines the access cover to the access cover rails. Alternatively, tabs or other mechanisms can be used to confine the access cover to the rails. The distance between the access cover rails will generally be approximately equal to the length of the access opening since the length and width of the access cover will generally be approximately equal to the length and width of the access opening. This provides for a complete closure of the access opening when the access cover is in the closed position. A lock pin inserted through an upper lock pin opening in an upper lock pin collar, through the access cover and through a lower lock and opening in the lower lock pin collar secures the access cover in the fully closed or partially closed position. The upper lock panel collar and lower lock pin collar are welded to the top and bottom respectively of the access opening frame. A first handrail section and a second handrail section are anchored on opposing sides of the platform deck. The first handrail section is anchored to the platform deck by a pair of first handrail anchor brackets and the second handrail section is anchored to the platform deck by a pair of second handrail anchor brackets. The first handrail section and the second handrail section respectfully are secured in the upright position by a handrail lock pin inserted in anchor bracket lock pin holes in opposing anchor bracket side walls and handrail lock pin holes in opposing sides of each handrail post, the anchor bracket lock pin holes and the handrail lock pin holes have been aligned when the handrail is in the upright position a kick tab on the inside face of each anchor bracket prevents each bottom of each handrail post from rotating inward and hence the top of the handrail from rotating outward, hence providing stability to the handrail in the upright position with the locking pins in place.
The third handrail section and a fourth handrail section are likewise anchored on opposing sides respectively of the platform deck. The third handrail section and fourth handrail section are perpendicular to the first handrail section and the second handrail section. Handrail sections three and four lay flat on top of handrail sections one and two when the handrail sections are retracted to the transport position.
With the handrail sections all in the upright position the perimeter safety chains are connected between the respective handrail sections thereby creating a safety barrier completely around the perimeter of the platform deck. The perimeter safety chains are connected at each end to the outside edge of the handrail section by a chain bracket. Generally for enhanced safety, an upper perimeter safety chain and a lower perimeter safety chain are used between adjacent handrail sections.
The platform may also be equipped with optional features such as the lifting chain storage box built into the platform deck and typically equipped with a hinged cover. A section of the hinged lifting chain storage box cover may also be equipped with a battery anchor bracket which allows a battery to be secured to the platform deck for use in powering the pipeline construction laser as well as lighting or ventilation for use in the manhole or on the platform.
The present invention shown has two sets of anchor pedestals, a set of four interior anchor pedestals and a set of four exterior anchor pedestals. The two sets of anchor pedestals provide for the utilization of the platform on two different sizes of manholes. Screw anchors extend from the anchor pedestals to secure the platform to the manhole.


A keyless locking system for a cart includes a lock mechanism with a drive mechanism in the form of a solenoid that is electrically coupled to an integrated circuit and a long lasting power supply. In an unenergized state, an armature of the solenoid prevents operation of the lock mechanism to release drawers supported by the cart. Upon entry of a correct access code via a keypad associated with the integrated circuit, current is supplied to the solenoid to permit operation of the lock mechanism and thereby release the drawers. Advantageously, the lock mechanism only draws from the power supply to temporarily release the solenoid only thereby requiring minimal power and significantly reducing the re-charging, replacement and maintenance requirements for the power supply and the down time for the cart.

This invention pertains to carts with lockable drawers and more particularly to a keyless locking system for medical carts.
Carts with lockable drawers are used for many applications. For example, a medical cart is used to administer medication to patients in hospitals or other care facilities. A typical medical cart has casters located at the bottom of the cart to permit easy movement of the cart by attending nurses to various patients"" rooms. The cart also has one or more drawers for storing patients"" medicines. Typically, each drawer is dedicated to storing the medication for an individual patient. Because the cart is used to store medications for several patients and is moveable from room to room, controlling access to the contents of the cart to prevent theft or misuse of medication and thereby protect the patients is important. One such medical cart, as described above, is disclosed in U.S. Pat. No. 5,743,607, to Teufel et al., which patent is commonly held by the assignee of the present invention and hereby incorporated by reference in its entirety.
Controlling access to medical carts in the past involved the use of manual key locks or complex electromechanical devices which permit a drawer locking tab to lock and unlock all of the drawers of the medical cart. U.S. Pat. No. 5,743,607, for example, discloses the use of a keypad with a system of locking tabs to lock the drawers of a cart. These prior art methods of locking carts or controlling access to medical carts, while being effective, do have certain limitations. For example, the keys for a manually locked cart can be lost or misappropriated by unauthorized persons. In the event that a key is lost and controlled access to the cart has been compromised, the changing of a keyed lock requires considerable time and expense during which time the cart cannot be used. In the case of electromechanical locks, prior art locking systems generally consume a considerable amount of power, requiring the systems to be charged daily for proper operation of the electromechanical locking mechanism. Furthermore, service, maintenance, and manufacture of prior art carts may be generally expensive and time consuming due to the complexity of the locking mechanisms.
Accordingly, there is a need for a simple, keyless cart locking system having low power consumption requirements and which is easy to manufacture and maintain, particularly for medical carts having lockable drawers.
This invention, in one embodiment, is a locking system for a cart with lockable drawers, such as a medical cart, and in another embodiment the invention is a cart with such a locking system. The locking system includes an integrated circuit which controls the actuation of a drive mechanism in the form of a solenoid to permit the operation by a user of a handle for release of the drawers. Advantageously, power to the solenoid is only provided to disengage the lock mechanism when a correct access code has been entered via a keypad or other user input device. Previously, locking mechanisms for carts of this type required a significant amount of power for actuation of the drive and lock mechanisms. Since this invention only briefly consumes power to disengage the drive mechanism, the system has very low power consumption requirements. The simple design of the locking mechanism also makes it easy to operate, manufacture and service.
The invention includes a lock mechanism having a handle which is manipulated by a user to disengage a locking tab of the medical cart. The lock mechanism includes a housing which supports the handle and a spring-loaded cam to disengage the locking tab. The lock mechanism further includes a drive mechanism in the form of a solenoid having a movable armature that positively engages the handle portion of the lock mechanism to prevent the lock mechanism from disengaging the locking tab when the solenoid is in an unenergized, or xe2x80x9cno loadxe2x80x9d state. The solenoid is connected to an integrated circuit having a keypad to accept user input such as an access code, and also to a power supply which provides power to the solenoid when the correct access code has been entered into the keypad. In a preferred embodiment, the power supply includes four D cell batteries to energize the solenoid on demand when the cart is to be unlocked.
The locking system of this invention preferably includes a manual override device to gain access to the drawers of the cart in the event of a loss of power or in the event the access code has been lost. The manual override device includes a flexible yoke which is connected to the armature of the solenoid. The yoke is actuated to disengage the armature from the handle by a conventional key lock coupled to and remotely located from the lock mechanism. In a preferred embodiment, the yoke is coupled to the remote key lock by a cable.
In another aspect of the invention, the housing of the lock mechanism has a clam-shell design, with hinges that facilitate easy assembly. The lock mechanism also includes a rod and handle assembly for an operator to disengage the drawer locking tabs of the cart. In this regard, the rod has a cam at one end which protrudes from the housing to move the locking tabs from a locked configuration to an unlocked configuration. The handle is inserted into an end of the housing opposite from the cam and is coupled to the rod.


A voice over DSL telephone system for a customer premises. The system includes a network interface device having a DSL filter coupling DSL service from a central office to the customer premises wiring and a switch for automatically connecting POTS service from the central office to the customer premises wiring whenever there is no active integrated access device, IAD, connected to the wiring. A detection circuit detects the presence or absence of the IAD and opens and closes the switch accordingly. Both DSL and POTS ports of an IAD may then be connected to the same customer premises wiring. Telephone sets are coupled to the customer premises wiring through low pass filters which block DSL frequencies.

Not Applicable.
Not Applicable.
Not Applicable.
The present invention relates to customer premises telecommunications systems and more particularly to a system which uses existing customer premises wiring for both POTS and DSL services without interference with local exchange carrier POTS service.
The common telephone service provided to customer premises, including homes and businesses, is analog service provided over copper wires usually referred to as twisted pair. This service is referred to as POTS, or plain old telephone system, service. It is sometimes considered to be synonymous with the public switched telephone network, PSTN. Most of the PSTN now carries signals digitally. However, POTS service from the local exchange carrier, LEC, central office, CO, to customer premises is analog and carried over copper wire. In addition to voice, the tip and ring signals and power to operate telephone sets in the customer premises are carried over the copper wires. An advantage of this system is that the telephone system does not depend on having power available at the customer premises. The CO normally uses standard grid power to operate and has emergency power backup systems which keep the telephone system operating in emergency situations.
Digital subscriber loops or lines, DSL, were developed to provide digital data service over the same twisted pair lines which are used for POTS. This type of service has great advantage when customers connect computers to the Internet or other networks from their homes or small business premises. Both POTS service and DSL service can be provided over the same copper wires so that no additional expense of running extra lines for DSL is required. POTS service operates at frequencies below 4 KHz while DSL operates at frequencies above 4 KHz up to several MHz. It is therefore a simple matter to separate the signals by frequency filters.
As the DSL service has become more available, it is becoming common to provide voice over DSL, VoDSL, service. In this type of service, the analog telephones in a customer premises are connected to a device, e.g. a VoDSL Integrated Access Device (IAD), which converts the analog telephone signals to digital signals and sends them to the CO over a DSL connection. An example of an IAD is the CPE, customer premises equipment, described in U.S. Pat. No. 6,272,209 issued on Aug. 7, 2001. This arrangement has a number of advantages. For example, a number of separate telephone voice signals can be transmitted simultaneously over one DSL connection. Data signals may also be transmitted over the DSL connection at the same time. There is no need to run additional twisted pairs when a customer wants additional telephones or additional computer connections. This arrangement effectively extends the PSTN digital system past the CO and into the customer premises.
VoDSL systems must have a source of electrical power. It has not proven practical to provide power from the CO as is done for POTS service. The power requirements are too great. As a result, the systems use power from the customer premises. For emergency purposes, the systems may have batteries for backup when the AC power is lost. However, such systems must be maintained by the customer to be sure that the backup batteries are charged and are replaced at regular intervals. In any case, backup batteries have a limited amount of power available and will run down after a long outage of AC power.
As VoDSL systems become more common, more customers want to perform their own installation. This requires that the system be easy and simple to install. Such systems should be designed to plug into existing wiring to the extent possible. Running new wiring in a customer premises requires a major effort which most customers would not want to undertake. It is also desirable that an IAD be located close to a customer""s personal computer, since they often have a network connection directly to the computer. However, in existing systems IADs must be connected between the copper wires entering the premises and the internal wires connected to the telephone sets. This normally requires breaking or interrupting the wiring at or near a location on the exterior of the customer premises. The analog signals between the IAD and the telephone sets in the customer premises must be isolated from the POTS service connection to the CO.
It would be desirable to have a voice over DSL system which is simple to install, does not require additional wiring in the customer premises and which provides telephone service when the VoDSL system loses power.
A voice over DSL system according to the present invention includes an improved network interface device, conventional customer premises wiring, and an integrated access device having both DSL and POTS ports coupled to the customer premises wiring. The improved network interface device includes a filter which couples DSL frequencies across the network interface device at all times and an automatic switch which opens when an integrated access device is operating to isolate POTS service in the customer premises from POTS service in a local exchange carrier central office.
In one embodiment, the invention includes a DSL blocking filter between a telephone set and its connection to the customer premises telephone wiring.


Methods, devices, and systems are provided in a multi-level computer architecture which provides improved capabilities for managing courseware and other content in a shared use operating environment such as a computer network. In particular, the invention provides a commercial networked instruction content delivery method and system which does not exclude synchronous sharing but is focused on asynchronous sharing. Security means in the architecture provide content property holders with the ability to know how many minutes of use an individual made of licensed material and with increased certainty that their material cannot be used, copied, or sold in usable form unless and until a user site is connected or reconnected to a minute-by-minute counter which is located off the premises of the user. This security link helps protect software and other works which are being sold or licensed to an individual, organization, or entity, and creates income opportunities for owners of such content.

The present invention relates to content delivery over a large computer network, and more particularly to a computer network architecture which integrates management components such as a reservation system, a funds flow system, a metering system, and a security system for preventing unauthorized use of courseware and other content.
More and more paintings, pictures, books, songs, other performances, texts, diagrams, recordings, video clips, and courses utilizing them for instructional purposes and/or entertainment are becoming available in machine readable forms. In particular, many computer-assisted lessons, training materials, and other instructional courses include works which can be protected under intellectual property laws, such as visual works, audio works, texts, examinations, simulations, and other works. Some sensory works experienced while using computers, such as the physical motions performed with a flight simulator, may also be protected. Still other computer-aided sensory experiences are foreseeable but not yet commercially implemented, such as smells that could enhance a fire fighting course or a course on the detection of illegal drugs. These will also benefit from protection.
xe2x80x9cComputerized trainingxe2x80x9d, xe2x80x9ccomputer-assisted instructionxe2x80x9d, xe2x80x9ccomputer-aided learningxe2x80x9d, xe2x80x9cweb-based trainingxe2x80x9d, xe2x80x9cintranet-based learningxe2x80x9d, xe2x80x9cweb coursesxe2x80x9d, xe2x80x9cvirtual universityxe2x80x9d, xe2x80x9ccomputerized curriculum delivery systemxe2x80x9d, xe2x80x9ccourseware delivery systemxe2x80x9d, xe2x80x9cinstructional management systemxe2x80x9d, xe2x80x9cinteractive educational methodxe2x80x9d, and similar phrases are used by various people in various ways, but each of these terms refers to efforts to use computers to help educate students. As used here, xe2x80x9cstudentsxe2x80x9d are not necessarily traditional students enrolled in high schools, colleges, universities, and the like, but are rather people who receive instruction through courseware. Courseware may be used by traditional students, but it may also be used by employees of government agencies and corporations, for instance.
To better understand the present invention in the context of existing computer-assisted educational efforts, it will helpful to understand certain distinctions, including without limitation the following:
Course authoring vs. course content delivery;
Stand-alone computer-based training vs. networked instruction;
Synchronous sharing vs. asynchronous sharing;
Commercial systems vs. academic systems; and
Technical vs. legal means for securing intellectual property.
Courseware vs. other content
Many uses of computers to facilitate education focus on providing authoring tools and authoring environments. For instance, tools for authoring include tools for re-formatting text into HTML format and adding hyperlinks; tools for integrating audio and/or video content with text content; and tools for creating interactive forms to obtain information from students and provide appropriate responses. In short, authoring tools help instructors create courseware content.
By contrast, delivery tools help deliver courseware to students. In the case of xe2x80x9cweb-based trainingxe2x80x9d, xe2x80x9cintranet-based learningxe2x80x9d, and xe2x80x9cweb coursesxe2x80x9d, delivery tools typically include TCP/IP networks and web browsers. Computer workstations themselves may also be viewed as delivery tools, particularly when the courseware is written to be used on a stand-alone computer rather than being delivered over a network connection.
Many existing approaches to computer-aided teaching include both authoring and delivery components. However, the problems and solutions associated with authoring are not necessarily the same as those associated with delivery. The present invention is concerned primarily with delivery as opposed to authoring.
Many computer-based training systems do not require a network connection in order to function. All necessary courseware content is stored on a computer disk, CD-ROM, or other medium which is directly accessible to the computer being used by the student, making it unnecessary to send any content over a network connection. The tools and techniques for managing courseware content in such stand-alone systems are basically the same as the tools and techniques for managing application programs, operating systems, and other types of software installed on user workstations, namely written licenses, disk copy-protection schemes, license serial numbers, and the like.
By contrast, network-based training approaches either take advantage of a network connection if one is available, or else they require such a connection. Different network-based systems use the network in different ways. Sometimes courseware content is stored on a server and delivered over the network to users as needed. In some cases, part or all of the content is stored on the local network node but licensing is enforced through a server. For instance, the content stored locally might be encrypted, and the decryption key might be available only from the server and then only after the user is authenticated. Some network-based educational systems allow students to interact with one another and/or with the instructor through email or chat rooms. Some systems administer tests by having the student send test answers to a server, which grades the test and notifies the student of the results. Some systems provide instructors with access over the network to a database of administrative information such as student grades and a list of the students who have viewed a given lesson. Of course, many systems combine one or more of these features and some also use networks in other ways.
The present invention is concerned with network-based courseware delivery systems, as opposed to stand-alone courseware delivery systems.
Networked courseware delivery systems may share content between multiple users synchronously or asynchronously. With synchronous sharing, users and/or instructors exchange information in a real-time or interactive way. Examples of synchronous sharing include telephone conversations, video conferencing, and chat rooms. By contrast, asynchronous sharing involves an exchange of information in which the participants expect substantial delays, or they involve a one-way flow of information rather than an exchange. Examples of asynchronous sharing include downloading a previously created multimedia presentation, listserv exchanges, and Usenet postings. Email does not fit neatly in either category, because it can be either synchronous or asynchronous in practice.
Some aspects of the present invention are concerned with asynchronous sharing, and in particular with asynchronous delivery of previously created courseware content. However, other aspects of the invention are concerned with synchronous information exchanges, such as funds transfers.
As noted, some courseware students attend traditional institutions of higher education. In many cases, those students pay for their use of courseware by paying tuition to the institution. If the institution is not the owner of the courseware, the institution then makes separate arrangements for payment to the owner. Likewise, students who are employees of a government agency or corporation generally receive access to courseware through their employer without personally making arrangements to pay the courseware owner directly. In either case, at the time a student sits down to actually use the course-ware it may be necessary to authenticate the student to the system but it is not necessary for the student to provide a credit card number or similar payment mechanism. For convenience, courseware management systems which do not require direct payment from students are referred to herein as xe2x80x9cacademic systemsxe2x80x9d.
By contrast, in xe2x80x9ccommercial systemsxe2x80x9d some provision must be made for funds transfer before a student is given full access to courseware content (although a demo might be available at no charge). For instance, each student may be required to provide a credit card number, to pre-pay for access by giving cash or a check to an attendant, or to provide individual billing information if credit is being extended.
The present invention is concerned primarily with commercial courseware delivery systems as opposed to academic courseware delivery systems.
As time passes, personal computers and other computational devices are able to record into machine readable form more and more complex presentations or experiences. For example, personal computers in the 1980""s mainly manipulated words, numbers, and characters; in the 1990""s manipulation of icons, images, audio and video has become commonplace. The next step may include widespread use of motion, as in simulators, and perhaps smell or other additions. As the complexity of the process needed to place these words, images, and other sensory experiences into machine readable form increases, the value of computer software that presents these experiences increases. This increases in turn the value of a security system which enforces courseware license agreements.
Intellectual property rights are provided by copyright and other laws to encourage creative effort by artists, authors, and other people who create paintings, photographs, animations, musical works, instructional texts, and other works. These works can be stored, presented, and utilized in many ways. With the increasing availability of powerful computers, many works that were traditionally available on paper, canvas, or tape are now stored in computer hard drives and computer RAM (random access memory), and are displayed on computer monitors such as cathode ray tube screens and liquid crystal displays.
Early computers provided minimal technical security means. On early personal computers, for instance, typing xe2x80x9ccopy *.*xe2x80x9d would direct the computer to copy every file or program in a directory. Further simple keystrokes, such as xe2x80x9ccopy C:/*.* A:/*.*xe2x80x9d would direct the computer to place the new copies in a new physical location, perhaps copying everything from a disk directory in drive C to a portable disk in drive A. Even today most personal computers routinely provide an environment that makes it relatively easy to copy electronic information in the form of files.
Of course, technical means are not the only way to protect intellectual property rights; legal tools in the form of license agreements are widely used. Perhaps the most widespread license agreement is a single workstation agreement. In exchange for a license fee or an outright purchase price, a set of disks or a CD-ROM containing digitized works and/or executable code is transferred to the purchaser, often with books and/or instructions on paper. Sometimes the works are transferred over a network such as the Internet in digital form. The purchaser is typically informed that the code or information may be used an unlimited number of times on a single workstation or other computer.
This approach worked fairly well in the day of the stand-alone personal computer. It does require that the producer of the code or other protectable work place some trust in the buyer, since the buyer often could copy the code or information onto more than one computer. The barriers were mainly legal, not technical. In locations where intellectual property was not a well-established and respected concept, widespread copying of information and executable code reduced income and profits to producers of computer based information and applications by diverting income and profits to illicit xe2x80x9cfactoriesxe2x80x9d which reproduced computer disks and CD-ROMs without permission from the rightful owner.
Many technical protection schemes were developed to combat the ability of the market to reproduce information without payment to the owner. Some xe2x80x9ccopy-protectionxe2x80x9d schemes made it difficult to make copies, regardless of the legitimacy (e.g. for unauthorized resale versus for proper backup) of the copies.
Other schemes defined zones of control on a CD-ROM and made a xe2x80x9ckeyxe2x80x9d necessary to read the zones. For instance, if a CD-ROM had 600 megabytes of information on it, a person might buy the legal right to see, view, or use 100 megabytes for $50.00. Information would be available in the first 100 megabyte zone regarding the contents and cost of information in the second or third 100 megabytes. For an additional fee or fees, the viewer could obtain the key to additional segments of the CD-ROM. For instance, a second $50 might buy the right to use the second 100 megabytes and a third $50 fee might permit the use of the third 100 megabytes.
A problem with this approach (and with copy-protection schemes) is that once a single purchase has been made of all the information, or access to all the information on the disk or CD-ROM has been obtained once, the information could be reproduced at will. An unauthorized factory could produce thousands of copies to be resold with no benefit to the rightful owner of the intellectual property.
Similar problems exist with the site license approach to protecting intellectual property. A licensed site such as a corporation or a government agency obtains the right to use a program or digitized information from the intellectual property owner, and is given a set of disks, CD-ROMs, or file-server-based copies of the licensed work for authorized internal use. The intellectual property owner relies upon the corporation or agency not to share the information or program outside the bounds of the license. But the major tool for enforcing the license agreement was not technical. Instead, it was respect for the law and the agreement. Unfortunately, some corporations and even some government agencies were staffed, at least in part, by people willing to take home a copy of the software or other licensed work and share it or sell it to an illegal copying factory.
Under a common relationship between works of intellectual property and the Internet, users view courseware and other information for free. The information is shared for free because providing the information helps the work""s owner sell a product, or saves the owner money by reducing technical support costs, for example. In the research community, huge sets of information are regularly exchanged via file transfer protocol or other digital means. Similarly, information in courses can be made available on the web, and can be viewed via a browser.
The present invention relates to protecting content both by technical means and by legal mechanisms. Although some information may be shared for free within a system according to the invention, much of the information available through the inventive system is provided only in exchange for license fees or the like paid by students or their employers.
Those of skill in the art will recognize that many of the comments above apply not only to courseware, but also to other types of digital content, including without limitation musical recordings, visual images, and the like. Such content may appear as components of multimedia courseware, but it may also be distributed independently of courseware and/or for purposes other than education. As used herein, xe2x80x9ccontentxe2x80x9d includes both courseware and other kinds of digital content.
In addition to the considerations above, certain trends are worth noting. Many courses are available on the web, yet in general the more attractive the course is (visually, in activity, motion, video, sound, and so on), the more time it takes to refresh the computer screen at the user""s workstation. To reduce download time, more and more bandwidth is requested. Users go from a POTS (xe2x80x9cplain old telephone systemxe2x80x9d) line, to an ISDN line to a T1 line, with increasing costs at each stage. However, the cost of computer storage is dropping rapidly. As most machine readable classes remain less than a gigabyte in size, the cost of forward storing a machine-readable class to the personal computer owner wishing to take the class is dropping rapidly.
As the speed of market developments in the computer industry increase, the delay and cost of obtaining legal remedies increase, and the technical ease of copying and distributing electronic information increases dramatically with the interconnections available via the Internet, improved tools for managing courseware are needed.
As discussed above, a wide range of computer-assisted educational features and capabilities have been explored, at least to some extent. However, existing approaches have been less successful at combining these features and capabilities into an architecture which securely and effectively shares commercial courseware. Accordingly, it would be an advancement in the art to provide an improved computer architecture for sharing commercial courseware and other content over a network.
The present invention provides improved capabilities for managing courseware and other content in a shared use operating environment such as a computer network. In particular, the invention provides a commercial networked content delivery method and system which does not exclude synchronous sharing but is focused on asynchronous sharing.
One method of the invention operates in a network containing a registration server, a content server connected to the registration server, and several client work-stations connected to the content server. After a user registers with the registration server and requests access, the content server authenticates the request and serves the content to the client workstation for presentation to the user. Content may be moved by the system between content servers in response to actual or anticipated user requests; users may reserve courses for later viewing. If the target content server lacks room to receive the incoming content, the system makes a recommendation to the local administrator as to which content should be deleted from the content server in order to make additional room.
Courseware and other content managed by the system may contain one or more xe2x80x9ccritical portionsxe2x80x9d which have been treated to prevent their unauthorized use and thereby enhance the protection of intellectual property rights in the content by technical means. For example, the treating step may insert disabling code into an executable portion of courseware, may encapsulate the critical portion in a database table, may compress the critical portion, and/or may encrypt the critical portion. In addition, the content server and/or client workstation may disable use of a critical portion if an expected security handshake is not received. Caching and other disk writes at the client may also be disabled to prevent a permanent copy of the critical portion from being created at the client. To take advantage of low cost telephone connections, part or all of the content may be downloaded to the client workstation one or more hours before serving the critical portion.
The system also monitors the connection between content server and client, and meters use of the content so that the user pays only for actual use. Pre-existing works can be metered without being modified. In some cases, however, a metering security module is injected by linking or recompilation into the machine readable form of a work that contains legally protectable intellectual property. Adding the metering security module alters the system, such as by inserting disabling code, so that the system will not play or display the content unless the metering security module is operating. xe2x80x9cPlayingxe2x80x9d a work includes displaying it, executing it, digitally manipulating it, or otherwise performing an act governed by the license agreement or by relevant intellectual property law. Unless the metering security module is engaged and authorizes the use, a monitor will not display certain protected words or images or motion images, speakers will not play certain protected sounds, motion simulators will not perform certain protected motions, and so forth.
The user receives an invoice for use of the courseware or other content. A local administrator can be authorized to adjust invoices in response to user requests. For instance, the administrator may determine that the user did not finish viewing the course in question, or accidentally started the wrong course, and then reduce the charges on that basis. If the user previously provided a credit card payment authorization to permit payment by credit card, a finds flow manager makes appropriate adjustments to the credit card charges.
In short, the architecture of the present invention provides improved security, efficiency, and convenience for the management of courseware or other content in a shared operating environment such as a network or a collection of loosely coupled networks. For instance, additional security is provided by separating registration information from content, by identifying and treating critical portions, and by monitoring the connection over which content is supplied to a client. Convenience and efficiency are provided by optional early downloading, by reservation capabilities, and by a combination of automatic and local administrator control. Additional features and advantages of the present invention will become more fully apparent through the following description.

Computer architecture for managing courseware in a shared use operating environment

Digital-Vending Services International, LLC


A composition including at least one solvent for cured product and at least one gelling or solidifying agent. The invention also provides a composition described above which is in the form of a soft solid, for example, in the form of a stick. A pack is also provided, comprising (i) a shaped mass of a composition, which includes at least one solvent for a cured product and at least one gelling or solidifying agent and a container (1) for the composition. The container (1) has a mechanism for expelling the shaped mass.

The present invention relates to semi-solid cured product removing compositions, particularly well suited to removal of cured product for example polymerized adhesive, from a substrate. In particular the semi-solid cured product removing compositions of the present invention are suited to removal of cured adhesives such as polycyanoacrylate from substrates.
Many types of curable products including adhesives are known and are well documented. Known curable products may be aerobic or anaerobic (cure in the absence of air) and may be formulated in one-or two-part compositions. The curable products may be adhesives, coatings, sealants and such like.
Many curable products present a certain amount of difficulty to users. For instance if curable product is spilled, misplaced, or otherwise makes its way onto an undesired substrate and cures there, it can be difficult to remove later on. Cured product can be removed for example by scraping, by use of further solvent or otherwise. One typical scenario is where the user of, for example an adhesive, mishandles, applies incorrectly or spills the product resulting in unwanted curing of the product, which may be on the skin of the hands etc. Instant adhesives are particularly prone to curing at unintended sites as they leave little or no time for removal before curing. Removal by washing with detergent or solvent may help to remove cured product. Solvents may be volatile evaporating before they have acted sufficiently on the cured product to assist in its removal. Cyanoacrylates are examples of adhesives which are commonly available. Most cyanoacrylate adhesives are instant adhesives curing within a short time of being applied. The cure speed of cyanoacrylates is often of the order of seconds or fractions of a second so that these products are difficult to remove.
It would however be desirable to provide a convenient way to remove such polymerized or cured composition which allowed for ease and convenience of removal of cured product. It would be particularly desirable to provide, an easy to use cured product remover, which could be easily applied to the undesired cured product and which would assist in the removal of the cured product.
It is well known for instance to formulate adhesives as xe2x80x9cstickxe2x80x9d compositions. The patent literature on stick adhesives is extensive and covers a broad range of adhesive types, from emulsion adhesives through solvent based adhesives, to contact adhesives as well as gelling and solidifying additives for the preparation of the sticks ranging from thermosetting through natural polymers to inert fillers. A well known example of one such adhesive stick sold under the trade name PrittStick(trademark) by Henkel KGaA which is an emulsion-based adhesive.
In the patent literature the following patents typify adhesive components which have been formulated as soft-solids, and more particularly sticks. U.S. Pat. No. 5,433,775 discloses an adhesive stick consisting of a water based preparation of starch derivatives and a soap gel as the shaping gel-forming component. See also U.S. Pat. No. 5,371,131.
U.S. Pat. No. 3,846,363 relates to an adhesive crayon composition containing a sorbitol-benzaldehyde reaction product as an additive. U.S. Pat. No. 4,639,475 discloses an adhesive stick composed of the reaction product of sorbitol and/or xylitol and benzaldehyde as the gel-forming composition together with an adhesive resin which is the reaction product of methyl vinyl ether/maleic acid anhydride copolymers with partially neutralised acid phosphate esters of non-ionic wetting agents of the lower alkylene oxide adduct type. Any of the gelling or solidifying agents of the prior art may be used in the present invention.
Japanese unexamined patent application laid open (Kokai) 51-103939 describes a stick-like epoxy adhesive and a stick-like epoxy hardening agent which is used therewith. The sticks are obtained by suitably compounding gelling agent or/and water and/or organic solvent with liquid or solution type epoxy adhesive and epoxy hardening agent.
DE 199 57 677 A1, published after the priority date of the present application, of Henkel KGaA, describes a cyanoacrylate adhesive, coating or sealing material which also contains at least one condensation product of an aldehyde or ketone with a polyol. The adhesive may be in stick form.
While a wide variety of sticks have been described, no previous suggestion has been made that a cured product removal composition could be made in stick form.
The present invention provides cured product removing composition suitable for formulation/presentation in stick form. The compositions are particularly useful for removal of cured adhesive for example polymerized cyanoacrylate adhesive. The compositions are easy to apply and handle allowing for accuracy in application without running on. They can be easily and conveniently applied to the desired site and will remain there until removed.
In particular the present invention provides:
a cured product removing composition including:
(a) at least one solvent for cured product; and
(b) at least one gelling or solidifying agent, which is solidified in stick form.
The composition, in contrast to known adhesive sticks is absent any cured or uncured polymerizable product. Known adhesive sticks are not suitable for use as cured product removers as these sticks contain polymerizable compounds which will polymerize exacerbating rather than alleviating the problem. It is clear therefore to the person skilled in the art that therefore no polymerisable monomer, or polymerised polymer in the composition, or in the stick if the composition is in stick form. The composition thus consists essentially of components (a) and (b). The composition does not include any components(s) which effect its ability to remove cured products. Components which could potentially effect its ability to remove cured products include polymerisable monomers/oligomers such as those of cyanoacrylate. It will be appreciated by those skilled in the art that the solvents which are useful for polymerized compounds are distinct from those which are suitable for the monomer or oligomer which polymerizes to form the cured product. The compositions of the present invention are most likely to be applied at room temperature under ambient conditions.
The composition is easily cast in stick form and is very useful in this respect. The present invention thus provides a cured product removing composition. In particular the cured product removing composition has been demonstrated as being particularly useful for removal of cured adhesive such as cyanoacrylate.
More particularly, the present invention relates to the preparation and use of a cured product removing composition in stick form. Suitably the composition is in the form of a soft-solid. The composition may be formulated in stick form for example by casting.
Component (b) is suitably the product of at least one aldehyde and/or ketone condensation reaction with a polyol.
Suitable polyols include those with at least one of a 1,2-diol, 1,3 diol or 1,4 diol structure. The diols may additionally have other groups such as ether, acid, amido, cyano, hemiacetal or halogen. Examples of suitable polyols include 1,2-ethandiol, 1,3-propandiol, 1,2-propandiol, 2,3-butandiol, 1,4-butandiol, 2,2-dimethyl-1,3-propandiol, 2,2-bis(hydroxymethyl)-1,3-propandiol, 2-(bromomethyl)-2-(hydroxymethyl)-1,3-propandiol, 1,3,4-butantriol, 1-phenyl-1,2,3-propantriol, 1,2-hexandiol, neopentylglycol, 1,4-bishydroxymethylcyclohexane, 2-methyl-1,3-propandiol, hexantriol-(1,2,6), 2-(2-hydroxyethoxy)butan-1,3,4-glycerine, di and polyglycerine, diglycerindiacetate, trimethylolpropane, di-(trimethylolpropane), trimethylolethane, pentaerythritol, bicyclo [2.2.1] heptane-2,3,5,6-tetrol, 2,2,3,3-tetrahydroxybutandiacid, dipentaerythritol, sorbitol, formitol, xylitol, inositol, glucitol, glucose, saccharose/sucrose, starch, cellulose, ascorbic acid, partially or fully hydrolysed polyvinylacetate, 9,10-dihydroxy stearic acid methyl ester, diacetylsorbitol and methylglyceride.
Most suitable polyols are sorbitol, xylitol and mannitol especially sorbitol.
Suitable aldehyde or ketones include those which have at least one substituted or unsubstituted aromatic, heteroaromatic or alicylic ring. These polyols may have additional groups such as ether ester, amide, cyano and halogen.
Examples of ketones include cyclopentanone, cyclohexanone, cycloheptanone, 1-(3,3-dimethylcyclohexyl)-ethanone, 1-cyclopropylethanone, 3-methyl-5-propylcyclohex-2-en-1-one, dicyclopropylmethanone, 4-tert-butylcyclohexanone, dicyclohexylmethanone, 4-methylcyclohexanone, 1-(1-methylcyclopropyl)-ethanone, (4-chlorophenyl)-cyclopropyl-methanone, 1-(1H-pyrrol-2-yl)-ethanone, 1-(2,4,6-trimethylphenyl)-ethanone, 1-(2-furanyl)-2-propanone, 1-(2-naphthalenyl)-ethanone, 1-(2-thienyl)-1-propanone, 1-(4-bromophenyl)-ethanone, 1-(4-methoxyphenyl)-ethanone, 1-(naphthalenyl)-ethanone, 1,1-diphenyl-2-propanone, 1,2-diphenylethanone, 1,3-diphenyl-2-propanone, 1-phenyl-1-butanone, 1-phenyl-1-decanone, 1-phenyl-1-dodecanone, 1-phenyl-1-hexanone, 1-phenyl-1-octanone, 1-phenyl-1-pentanone, 1-phenyl-1-penten-3-one, 1-phenyl-1-tetradecanone, 1-phenyl-2-butanone, 1-phenyl-2-propanone, 1-pyrazinyl-ethanone, 2,2,2-trifluoro-1-phenyl-ethanone, 1-(2-furanyl)-ethanone, 1-(2-pyridinyl)-ethanone, 1-(2-thienyl)-ethanone, 4-chloro-1-(4-fluorophenyl)-1-butanone, 4-phenyl-2-butanone, 1-phenyl-ethanone, bis-(2-hydroxyphenyl)-methanone, bis-(4-chlorophenyl)-methanone, cyclopentylphenylmethanone, cyclopropyl(4-methoxyphenyl)-methanone, cyclopropyl-(4-methylphenyl)-methanone, cyclopropyl-2-thienyl-methanone, cyclopropylphenylmethanone, 1,5-diphenyl-1,4-pentadien-3-one, phenyl-2-pyridinyl-methanone, 2-bromo-1-(4-nitrophenyl)-ethanone, 2-naphthalenylphenyl-methanone, 3-chloro-1-phenyl-1-propanone, 4-(4-hydroxyphenyl)-2-butanone, 4-(4-methoxyphenyl)-3-buten-2-one, 1-(4-pyridinyl)-ethanone, 1-(4-hydroxyphenyl)-ethanone, 1-phenyl-1-propanone, 4-phenyl-3-buten-2-one, diphenylmethanone, 1-phenyl-2-butanone, 1-phenyl-2-buten-1-one, bis-(4-methylphenyl)-methanone, 2-methyl-1-phenyl-1-propanone, 2-chloro-1-phenyl-ethanone, cyclopropyl-(4-fluorophenyl)-methanone, 1-(p-methoxyphenyl)-2-propanone, cyclohexylphenylmethanone and phenyl-(2-thienyl)-methanone.
The following aldehydes are exemplary of those suitable for use in the present invention benzaldehyde, 3-chlorobenzaldehyde, 4-chlorobenzaldehyde, 2,6-dichlorobenzaldehyde, 2,4-dinitrobenzaldehyde, 3,4-dichlorobenzaldehyde, 3-fluorobenzaldehyde, 4-bromobenzaldehyde, 2-methyltetrahydrobenzaldehyde, tetrahydrobenzaldehyde, 2-methyl-5-isopropylcyclopenten-1-aldehyde, 2,2,4-trimethylcyclohexa-4,6-dien-1-aldehyde, 3(4)-methyl-1-propylcyclohexen-3-aldehyde, 1,3(4)-dimethylcyclohexen-3-aldehyde, 2-methyl-1-propylcyclohexen-3-aldehyde, 3-cyclohexen-1-aldehyde, 2,3,4,5,6-pentafluorobenzaldehyde, 2,4,6-trihydroxybenzaldehyde, 4-tolylacetaldehyde, 2-methylbenzaldehyde, 4-hydroxybenzaldehyde, 3-methylbenzaldehyde, 2-hydroxy-1-naphthalaldehyde, 4-methylbenzaldehyde, 3,5-dimethoxy-4-hydroxybenzaldehyde, cinnam-aldehyde, 3-nitrobenzaldehyde, 2-pentylcinnamaldehyde, 4-diethylaminobenzaldehyde, 4-methoxybenzaldehyde, 2-phenylpropionaldehyde, 2-methoxycinnamaldehyde, 4-methylbenzaldehyde, phenoxyacetaldehyde, methylpyrrol-2-aldehyde, 2,5-dimethoxytetrahydrofuran-3-aldehyde, 2,5-dipropyl-3,4-dihydropyran-2-aldehyde, 2,5-diethyl-3,4-dihydropyran-2-aldehyde, 2,5-diisopropyl-3,4-dihydropyran-2-aldehyde, 2,5-dimethyl-3,4-dihydropyran-2-aldehyde, 2,5-dibutyl-3,4-dihydropyran-2-aldehyde, thiophen-3-aldehyde, indol-3-aldehyde, pyridine-3-aldehyde, pyridine-4-aldehyde and n-methylpyrrole-2-aldehyde.
Desirable aldehydes include benzaldehyde, 3-chlorobenzaldehyde and 3-fluorobenzaldehyde.
Particular acetals and ketals include: di-O-benzylidenmannitol, di-O-(2-chlorobenzylidene)mannitol, di-O-(4-nitrobenzylidene)mannitol, di-O-(3-fluorobenzylidene)mannitol, O-benzylidenesorbitol, di-O-benzylidenesorbitoldiacetate, di-O-(2-chlorobenzylidene)sorbitoldiacetate, tri-O-(4-chlorobenzylidene)sorbitol, O-benzylidenethreitol, O-benzylidene tartaric acid methylester, O-cyclohexylidenglycerine, O-cyclohexylidene ascorbic acid and O-benzylidene-9,10-dihydroxy stearic acid methylester.
Suitably the aldehyde is benzaldehyde, 3-chlorobenzaldehyde or 3-fluorobenzaldehyde especially benzaldehyde. Suitably the polyol is sorbitol, xylitol or mannitol especially sorbitol. The condensation product may be di-O-benzylidene mannitol; di-O-(3-fluorobenzylidene) mannitol or di-O-benzylidene sorbitol especially di-O-benzylidene sorbitol.
Suitable gelling agents for inclusion as component (b) include acetals of sugars, particularly acetals of sorbitol, which are particularly effective as gelling agents. One such gelling agent includes di-O-dibenzylidene sorbitol (also referred to simply as dibenzylidene sorbitol) sold by Roquette Freres, France under the trademark Disorbene(trademark). Other acetals such as those described above have also been found to be useful.
Acetals of sugars, particularly natural sugars, for example acetals of sorbitol, have been previously used as gelling agents for the preparation in stick form and these materials are useful in the present invention.
Component (b) the gelling or solidifying agent is useful for the preparation of a stick from the compositions of the present invention.
Suitably component (b) the gelling or solidifying agent has a concentration in the solvent from about 0.01% to about 20%, such as about 0.01% to about 15%, typically from about 0.05% to about 10% for example about 0.1% to about 5% weight by weight based on the total weight of the composition.
Suitably component (a) the solvent for (dissolving or swelling) cured product comprises an organic solvent in which the target cured product may be at least partially soluble. Component (a) may be an organic solvent selected from at least one of the following:
(i) carbonates such as propylene carbonate and ethylene carbonate
(ii) ketones, such as acetone, diethyl ketone, dipropyl ketone, diisopropyl ketone, methyl isopropyl ketone, methyl butyl ketone, methyl isobutyl ketone, ethyl propyl ketone,
(iii) esters such as ethyl acetate, acetonitrile, cyanoacetates for example ethyl cyanoacetate, methyl cyanoacetate, propyl cyanoacetate and butyl cyanoacetate and lactones such as gamma butyrolactone,
(iv) hydrocarbons, in particular aromatic hydrocarbons such as benzene, toluene and xylene,
(v) sulfoxides such as dimethyl sulfoxide,
(vi) those containing at least one amine group such as dimethylformamide, and
(viii) nitroalkanes such as nitromethane.
Desirably the solvent is propylene carbonate. Also desired for use in the present invention are the cyanoacetates for example ethyl cyanoacetate, methyl cyanoacetate, propyl cyanoacetate and butyl cyanoacetate.
It will be appreciated that the above mentioned solvents could be grouped in many different ways. The above solvents have been grouped in this particular way for ease of discussion. The solvent is for the polymerized product, for example polycyanoacrylate, and it will be apparent to persons skilled in the art which solvent is appropriate in the circumstances. It will be appreciated also that mixtures of solvents can also be used.
Many of the solvents useful in the compositions of the present invention are relatively volatile though they remain where applied in the compositions of the invention for a substantially longer period than the neat solvent would tend to remain. The solvent is thus applied in a convenient form directly to the substrate to be cleaned and the solvent will tend not to evaporate.
The function of the solvent is to assist dislodging of the cured product. This is achieved by the action of the solvent on the polymerized product. As relatively small amounts of solvent may be applied by the user there may not be in any given instance sufficient solvent to solubilize the entire amount of polymerized product. However the solvent does assist in the removal of the product nonetheless as even relatively small amounts of the solvent can act on the product causing it to swell. The swelling of the product is the result of debonding of the product caused by the action of the solvent and the product may become soft and exhibit a sticky or gummy consistency. The product is then easily removed for example by washing or scraping. The term xe2x80x9cpartially dissolvingxe2x80x9d as used herein with reference to solvents used in the present invention includes solvents or mixtures of solvents which cause this swelling effect.
The cast stick form is particularly desirable as this allows the product removing composition to be applied in a convenient form. A coating of the composition of selected thickness can be applied to the cured product and left to act. The composition gradually causes the cured product to swell over time to a soft and gummy consistency. The cured product is then in a convenient for removal. Therefore, any common solvent (or mixture of solvents) in which the cured product dissolves or partially dissolves including those solvents (or mixture of solvents) which will cause the cured product to swell will suffice. The skilled person will know to choose the appropriate solvent(s) for removal of the cured product in question. It will be appreciated that the cured product may be only partially cured at the time it is desired to remove it. The other requirement is that the solvent is one which can be solidified by component (b) at the least one gelling or solidifying agent.
Desirably the composition when solidified has the consistency of a soft-solid or waxy mass. The rheological properties of the mass of product should be such that the mass has a stable geometric shape. It is desirable that the shaped mass e.g. a stick, is applicable by manual rubbing against the substrate to which it is to be applied. The soft or semi-solid mass should be shearable under relatively modest manual pressure to allow for ease of application. It is desirable that the shaped mass retains its shape, for example when stored at 20xc2x0 C. for a number of days, more desirably for a number of weeks or months. The compositions exemplified herein have proven to be stable (and active) over a number of months and were still active a year later (and looked like remaining active over a further substantial period) when stored under such conditions. The cast composition has the ease of handling advantages of a completely solid material yet remains easily dispensable. PrittStick(trademark) is one commercially available semi-solid mass sold as an adhesive stick which is well known to be dispensable by rubbing to the substrate to which it is desired to be applied and which has a consistency which is very similar to the soft-solids of the present invention.
The invention also relates to the solidified product of a composition as described above. Suitably the composition is solidified in a desired geometric form, for example in a cylindrical shape. Any suitable shape which allows for ease or handling is desired and such shapes are typically referred to as sticks.
One method of preparing a soft-solid or semi-solid mass of the composition includes the steps of:
(i) heating a composition comprising: (a) at least one solvent for (dissolving or partially dissolving) cured product; and (b) at least one gelling or solidifying agent to a desired temperature; and
(ii) allowing the composition to cool or cooling the composition sufficiently to set the composition.
Typically the composition will set (solidify to a soft-solid) at a temperature of below about 30xc2x0 C. for example at about 15-21xc2x0 C.
The invention also relates to a shaped mass prepared by the method just described and particularly a mass shaped in a stick form.
It will be appreciated that if the composition is cast before cooling to its set temperature then it will take the shape of the container or mould in which it is cast. It is desirable that the composition be cast in a desired geometric shape for example as a stick for example a stick of a generally cylindrical shape. The person skilled in the art will appreciate that the pre-and post-casting composition will have essentially the same compositional make-up, with mainly physical changes from liquid to solid occurring during casting. Little or no solvent will be lost during the casting process. The concentration of the various components thus remains essentially unchanged as between the liquid and solidified (pre- and post-casting) compositions.
In a further aspect the invention provides a method of removing cured product from a substrate comprising contacting a sufficient amount of a composition according to the present invention with the cured product (for a sufficient period) to at least partially remove the cured product. The composition of the present invention may suitably be applied by (manually) rubbing the remover stick to the cured product the substrate. The composition of the invention may act by at least partially dissolving or swelling the cured product.
The invention thus discloses the use of at least one gelling or solidifying agent in the manufacture of a castable cured product removal composition.
The invention also provides an easy to use and consumer-friendly pack comprising:
(i) a shaped mass of a composition according to the invention (a cast composition); and
(ii) a container for the composition, the container having a mechanism for expelling the shaped mass. The pack may thus be sold as an article of commerce.
For example the container may have a mechanism for moving the shaped mass between a position where the shaped mass projects from the container, and a position where the shaped mass is substantially located (retracted) within the container. The composition is thus expellable. Suitably the container is a tubular container.
The composition may be cast directly in the container. The container may be of the type having a displaceable mechanism for example a carrier for displacing the mass of the composition relative to the container. The carrier may move the mass so that it projects from the container, or retract the mass so that it is housed within the container. In this way the mass may be extended for application to a substrate or retracted for storage. The container may comprise a cap for protection of the mass when the composition is not in use. Desirably the container has means for manual adjustment of the position of the mass or carrier, for example where the carrier is reciprocally threaded on a winding mechanism and can thus be extended or retracted by rotation of the winding mechanism in one of two directions.
It will be appreciated by those skilled in the art that a multitude of suitable containers may be used with the shapes masses or sticks of the present invention. Typically used containers are those with propulsion (expelling) mechanisms to propel the stick out of the container. Many such containers are known for example for deodorants/anti-perspirants, and make-up such as lipstick etc. The stick compositions of the present invention can thus be considered xe2x80x9cremover sticksxe2x80x9d for example glue remover sticks.

Semi-solid compositions for removing cured product


The present invention relates to blowing agent compositions that contain at least one hydrofluorocarbon having a boiling point of 30xc2x0 C. or higher and lower than about 120xc2x0 C., at least one hydrofluorocarbon having a boiling point lower than 30xc2x0 C., and at least one component selected from low-boiling alcohols and low-boiling carbonyl compounds. The present invention also relates to processes for preparing polymeric foam using such blowing agent compositions, as well as polymeric foams and foamable polymer compositions containing such blowing agent compositions.

1. Field of the Invention
The present invention relates to a blowing agent composition containing a hydrofluorocarbon (HFC) having a boiling point of 30xc2x0 C. or higher and lower than about 120xc2x0 C. (mid-range low-boiling HFC), a HFC having a boiling point lower than 30xc2x0 C. (low-range low-boiling HFC), and at least one component selected from low-boiling alcohols and low-boiling carbonyl compounds. The present invention further relates to polymeric foams and the use of such a blowing agent composition to produce polymeric foams, and foamable polymer compositions comprising a polymer that has such blowing agent compositions dispersed therein.
2. Description of Related Art
Low-boiling alcohols are useful components in blowing agent compositions for preparing polymeric foams. xe2x80x9cLow-boiling alcoholxe2x80x9d and xe2x80x9cLBAxe2x80x9d are interchangeable terms herein and refer to an alcohol having a boiling point lower than about 120xc2x0 C. LBAs can plasticize a polymer (see, e.g., U.S. Pat. No. 4,663,360 column 12 lines 50-52), facilitating polymer expansion at lower pressures than a non-plasticized polymer. Furthermore, LBAs tend to maintain or increase foam cell sizes even at relatively high concentrations, concentrations where other blowing agents tend to act as nucleators and reduce foam cell sizes. As a result, one may use relatively high concentrations of alcohol to reduce foam density without reducing foam cell size. Reducing density without reducing cell size is attractive for preparing thermally insulating polymeric foam.
Unfortunately, alcohols have drawbacks when used as blowing agents. An alcohol can react with halogenated components that are present in the foam, such as halogenated flame retardants, to produce a corrosive acid. The acid tends to corrode metal equipment. Furthermore, alcohols can escape into the atmosphere whereby they contribute undesirably to volatile organic compound (VOC) emissions.
Low-boiling carbonyl compounds, such as ketones and aldehydes, can facilitate production of a polymeric foam similarly to alcohols, but do so without significantly contributing to acid production. xe2x80x9cLow-boiling carbonyl compoundxe2x80x9d and xe2x80x9cLBCxe2x80x9d are interchangeable terms and refer to an aldehyde or ketone that has a boiling point lower than about 120xc2x0 C. Unfortunately, residual LBCs can also escape into the atmosphere whereby they contribute undesirably to volatile organic compound (VOC) emissions.
Blowing agents comprising HFCs are gaining popularity as regulations encourage replacing hydrochlorofluorocarbon (HCFC) and chlorofluorocarbon (CFC) blowing agent components, both of which can contribute to ozone depletion. HFCs have a thermal conductivity lower than most polymers or blowing agents (other than HCFCs and CFCs) so HFC residuals in a polymeric foam can lower the foam""s thermal conductivity.
Unfortunately, low-range low-boiling HFCs tend to escape from polymeric foam thereby causing an undesirable increase in polymeric foam thermal conductivity and organic emissions over time. Exploration of mid-range low-boiling HFCs such as 1,1,1,3,3-pentafluorobutane (HFC-365 mfc) as blowing agents is underway. Mid-range low-boiling HFCs can also reduce polymeric foam thermal conductivity and tend to reside within polymeric foam longer than low-range low-boiling HFCs.
A blowing agent composition that benefits from the advantages of a LBA and/or LBC compound yet has less of the detrimental affects of the alcohol and/or carbonyl compound is desirable. A blowing agent composition that further comprises HFCs to reduce the thermal conductivity through a polymeric foam is also desirable, particularly if a mid-range low-boiling HFC partially replaces a low-range low-boiling HFC.
xe2x80x9cHydrofluorocarbonxe2x80x9d and xe2x80x9cHFCxe2x80x9d are interchangeable terms and refer to an organic compound containing hydrogen, carbon, and fluorine, the compound being substantially free of halogens other than fluorine.
xe2x80x9cBoiling pointxe2x80x9d refers to the boiling point at one atmosphere pressure.
xe2x80x9cMid-range low-boiling hydrofluorocarbonxe2x80x9d, xe2x80x9cmid-range low-boiling HFCxe2x80x9d, and xe2x80x9cMRLB HFCxe2x80x9d are interchangeable terms and refer to a HFC that has a boiling point of 30xc2x0 C. or higher and lower than about 120xc2x0 C.
xe2x80x9cLow-range low-boiling hydrofluorocarbonxe2x80x9d, xe2x80x9clow-range low-boiling HFCxe2x80x9d, and xe2x80x9cLRLB HFCxe2x80x9d are interchangeable terms and refer to a HFC that has a boiling point lower than 30xc2x0 C.
xe2x80x9cFreshxe2x80x9d refers to within one month, preferably within one week, more preferably within one day, still more preferably within one hour, most preferably immediately after manufacture.
xe2x80x9cLBA and/or LBCxe2x80x9d means xe2x80x9cLBA, LBC, or LBA and LBCxe2x80x9d.
A polymeric foam or blowing agent composition that is xe2x80x9cessentially freexe2x80x9d of a specified component or components refers to a polymeric foam or blowing agent composition, respectively, that contains ten weight-percent (wt %) or less, preferably five wt % or less, more preferably one wt % or less, still more preferably 0.5 wt % or less, most preferably zero wt % of the specified component(s).
In a first aspect, the present invention is a blowing agent composition comprising: (a) at least one hydrofluorocarbon having a boiling point of 30xc2x0 C. or higher and lower than about 120xc2x0 C.; (b) at least one hydrofluorocarbon having a boiling point lower than 30xc2x0 C.; and (c) at least one component selected from low-boiling alcohols and low-boiling carbonyl compounds. Embodiments of the first aspect include compositions that are essentially free of low-boiling carbonyl compounds and compositions that contain at least one of ethanol, acetone, and additional blowing agents. One preferred embodiment of the first aspect further comprises carbon dioxide at a concentration of less than 50 weight-percent of the composition. Another preferred embodiment of the first aspect comprises 1,1,1,3,3-pentafluorobutane, 1,1,1,2-tetrafluoroethane, ethanol, and carbon dioxide, wherein carbon dioxide is less than 50 weight-percent of the composition.
In a second aspect, the present invention is a process for preparing polymeric foam comprising the steps: (a) forming a foamable polymer composition from a polymer and the blowing agent composition of the first aspect; and (b) expanding said foamable polymer composition into a polymeric foam.
In a third aspect the present invention is a polymeric foam that comprises: (a) a polymer; (b) a hydrofluorocarbon having a boiling point of 30xc2x0 C. or higher and lower than about 120xc2x0 C; (c) a hydrofluorocarbon having a boiling point lower than 30xc2x0 C; and (d) at least one component selected from low-boiling alcohols and low-boiling carbonyl compounds.
In a fourth aspect, the present invention is a foamable polymer composition comprising a polymer that has the blowing agent composition of the first aspect dispersed therein.
Surprisingly, low foam thermal conductivity and ease of processing associated with a blowing agent composition consisting of a LRLB HFC and a LBA and/or LBC is achievable by partially replacing at least one of the LRLB HFC, LBA and LBC with a MRLB HFC. Furthermore, one may achieve a lower foam thermal conductivity 90 days after formation by partially replacing at least one of LRLB HFC, LBA, and LBC with a MRLB HFC in the foam""s blowing agent composition.
The blowing agent compositions of the present invention are particularly useful for preparing thermally insulating polymeric foam.
This invention relates to a blowing agent composition comprising at least one MRLB HFC, at least one LRLB HFC, and at least one component selected from LBAs and LBCs.
Suitable LBAs include aliphatic alcohols having from one to five carbons (C1-C5) such as methanol, ethanol, n-propanol, and isopropanol. LBAs may or may not be anhydrous, but anhydrous (containing less than 1 weight-percent (wt %) water based on weight of alcohol) is preferred. The LBA is preferably ethanol or isopropanol, more preferably anhydrous ethanol.
Suitable LBCs include any ketone or aldehyde that has a boiling point lower than about 120xc2x0 C. Illustrative LBCs include acetone, 2-butanone, and acetaldehyde.
The blowing agent composition may be free of LBA if a LBC is present, and may be free of LBC if a LBA is present, or may contain both a LBA and a LBC. The combined concentration of LBA and LBC, based on the blowing agent composition weight, is greater than zero wt %, preferably at least one wt %, more preferably at least five wt %, still more preferably at least 10 wt %; and typically 60 wt % or less, preferably 50 wt % or less, more preferably 40 wt % or less, still more preferably 20 wt % or less. LBA and/or LBC concentrations greater than 60 wt % tend to excessively plasticize the polymer, making processing difficult and result in inadequate polymeric foam thermal stability.
Suitable MRLB HFCs include any HFC having a boiling point of 30xc2x0 C. or higher and lower than about 120xc2x0 C. Examples of suitable MRLB HFCs include aliphatic compounds such as HFC-365 mfc, 1-fluorobutane, nonafluorocyclopentane, perfluoro-2-methylbutane, 1-fluorohexane, perfluoro-2,3-dimethylbutane, perfluoro-1,2-dimethylcyclobutane, perfluorohexane, perfluoroisohexane, perfluorocyclohexane, perfluoroheptane, perfluoroethylcyclohexane, perfluoro-1,3-dimethyl cyclohexane, and perfluorooctane; as well as aromatic compounds such as fluorobenzene, 1,2-difluorobenzene; 1,4-difluorobenzene, 1,3-difluorobenzene; 1,3,5-trifluorobenzene; 1,2,4,5-tetrafluorobenzene, 1,2,3,5-tetrafluorobenzene, 1,2,3,4-tetrafluorobenzene, pentafluorobenzene, hexafluorobenzene, and 1 -fluro-3-(trifluoromethyl)benzene. HFC-365 mfc is particularly desirable due to its increasing availability and ease of use. Aromatic HFCs may also be attractive for preparing polymeric foams using an aromatic polymer if an enhanced compatibility between the HFC and polymer helps retain the HFC in the polymeric foam after formation. One advantage MRLB HFCs have over LRLB HFCS, in general, is that they typically remain longer within polymeric foam. HFC retention is attractive for slowing thermal conductivity increases and organic emissions associated with escaping HFC. MRLB HFCs are also easier to handle than LRLB HFCs because they are in a condensed phase at atmospheric pressure (760 mm mercury), therefore do not require liquefaction during the foaming process.
The blowing agent compositions of the present invention comprise a MRLB HFC at a concentration relative to blowing agent composition weight of greater than zero wt %, generally ten wt % or more, more generally five wt % or more, still more generally three wt % or more; and generally 40 wt % or less, more generally 60 wt % or less, still more generally 80 wt % or less, and most generally 95 wt % or less. At a concentration greater than 95 wt %, MRLB HFC will excessively plasticize the polymer making foaming difficult.
The blowing agent composition also comprises a LRLB HFC. The LRLB HFC typically acts both as-a blowing agent and as a thermal insulator in the polymeric foam. LRLB HFCs have low thermal conductivities, similar to the MRLB HFCs. Therefore, residual LRLB HFC in blown polymeric foam helps reduce the foam""s thermal conductivity. LRLB HFC residuals generally occupy cell spaces while MRLB HFC residuals generally condense onto or into cell walls. Therefore, LRLB HFCs are generally more efficient at reducing polymeric foam thermal conductivity than MRLB HFCs.
Suitable LRLB HFCs include methyl fluoride, difluoromethane (HFC-32), perfluoromethane, ethyl fluoride (HFC-161); 1,1-difluoroethane (HFC-152a); 1,1,1-trifluoroethane (HFC-143a); 1,1,2,2-tetrafluoroethane (HFC-134); 1,1,1,2-tetrafluoroethane (HFC-134a); pentafluoroethane (HFC-125), perfluoroethane, 2,2-difluoropropane (HFC-272fb), 1,1,1-trifluoropropane (HFC-263fb), 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea), 1,1,1,3,3-pentafluoropropane (HFC-245fa), and mixtures thereof. A preferred LRLB HFC is HFC-134a.
The concentration of LRLB HFC in the blowing agent composition, relative to the total composition weight, is greater than zero wt %, often 10 wt % or more, more often 15 wt % or more, still more often 30 wt % or more, most preferably greater than 50 wt %.
The upper concentration limit of LRLB HFC depends primarily on the solubility limit of the LRLB HFC in the polymer. Concentrations exceeding the solubility limit of a LRLB HFC in the polymer, in conjunction with the rest of the blowing agent composition, result in excessive nucleation during polymer expansion (blowing of the foam). A skilled artisan can determine without undue experimentation an upper limit for a LRLB HFC in a given blowing agent composition. The concentration of LRLB HFC is 95 wt % or less (relative to blowing agent composition weight), desirably 80 wt % or less, preferably 75 wt % or less, more preferably 60 wt % or less.
The blowing agent composition preferably comprises at least one additional blowing agent, although additional blowing agents are not necessary. Additional blowing agents are useful for decreasing foam density. Proper choice of additional blowing agents may increase total moles of blowing agent without decreasing cell size, increasing density, and/or decreasing dimensional stability.
Suitable additional blowing agents include inorganic and organic blowing agents as well as chemical blowing agents that decompose into inorganic and/or organic blowing agents. Suitable inorganic blowing agents include nitrogen, argon, water, air, and helium. Organic blowing agents include carbon dioxide (CO2), ethers, aliphatic hydrocarbons having from one to nine carbons (C1-9), fully and partially halogenated C1-4 aliphatic hydrocarbons. Aliphatic hydrocarbons include methane, ethane, propane, n-butane, isobutane, n-pentane, isopentane, neopentane, cyclobutane, and cyclopentane. Preferred additional blowing agents include water, CO2, isobutane, and cyclopentane. The most preferred additional blowing agent is CO2.
In general, the concentration of any individual additional blowing agent in a blowing agent composition is below the solubility limit of that blowing agent in the polymer at a process temperature (typically the glass transition temperature of the polymer) and in the presence of the entire blowing agent composition. In general, additional blowing agents comprise 50 wt % or less, 30 wt % or less, even 10 wt % or less of the blowing agent composition.
The sum of CO2, MRLB HFC, LRLB HFC, LBA, LBC, and any additional blowing agents account for 100 wt % of the blowing agent composition.
An example of a preferred blowing agent composition is 45-60 wt % HFC-134a, 25-40 wt % HFC-365 mfc, 10-20 wt % ethanol, and 1-10 wt % CO2.
The present invention also relates to the use of a blowing agent composition comprising a LBA and/or LBC, a MRLB HFC, and a LRLB HFC to prepare foamable polymer compositions and polymeric foam.
Any conventional blown foam process is suitable for preparing blown polymeric foam using a blowing agent composition of this invention. Generally, polymeric foam is prepared by plasticizing a polymer, incorporating therein a blowing agent composition at an initial pressure to form a foamable composition, and then exposing the foamable composition to a foaming pressure that is lower than the initial pressure and allowing the foamable composition to expand into polymeric foam. Typically, incorporate the blowing, agent composition at a concentration, relative to weight parts of polymer resin, of greater than zero parts-per-hundred (pph), preferably greater than 5 pph; and typically less than 25 pph, preferably less than 20 pph, and more preferably less than 15 pph to form a foamable polymer composition. Using greater than 25 pph blowing agent composition can produce foam with an undesirable density and cell size.
A typical process for forming a foamable polymer composition includes: (1) plasticizing a polymer, typically by heating it to a processing temperature at or above its glass transition temperature or melting temperature, to form a plasticized polymer; and (2) adding a blowing agent composition to the plasticized polymer at an initial pressure to form a foamable polymer composition. Add components of the blowing agent composition individually or in any combination. Incorporate the blowing agent composition into the plasticized polymer by a batch or continuous process, using conventional equipment such as an extruder or mixer blender. The initial pressure is sufficient to prevent substantial expansion of the foamable composition and to generally disperse the blowing agent composition into the plasticized polymer. The initial pressure is usually, though not necessarily, greater than atmospheric pressure.
Foam the foamable polymer composition by either reducing the pressure around the foamable composition to a foaming pressure or by transporting the foamable composition into a foaming zone at a foaming pressure. The foaming pressure is lower than the initial pressure and can be above or below atmospheric pressure, but is typically atmospheric pressure. Blowing agents in the blowing agent composition expand at the foaming pressure, expanding the foamable polymer composition into a polymeric foam.
Cooling a heat plasticized foamable composition below the processing temperature prior to exposing the foamable composition to the foaming pressure is useful for optimizing foam properties. Cool the foamable composition in an extruder or other mixing device or in separate heat exchangers.
A skilled artisan recognizes there are many variations of the general procedure as well as other ways to prepare polymeric foam that are suitable for purposes of the present invention. For example, U.S. Pat. No. 4,323,528, herein incorporated by reference, discloses a process for making polymeric foams via an accumulating extrusion process. The process comprises: 1) mixing a thermoplastic material and a blowing agent composition to form a foamable polymer composition; 2) extruding the foamable polymer composition into a holding zone maintained at a temperature and pressure that precludes foaming of the foamable polymer composition, the holding zone having a die defining an orifice opening into a zone of lower pressure and an openable gate closing the die orifice; 3) periodically opening the gate; 4) applying mechanical pressure substantially concurrently with (3) by means of a movable ram on the foamable polymer composition to eject it from the holding zone through the die orifice into the zone of lower pressure, and 5) allowing the ejected foamable polymer composition to expand to form a polymeric foam in the zone of lower pressure.
Suitable polymers for use in the present invention include thermoplastic polymers. Suitable thermoplastic polymers include those selected from a group consisting of vinyl aromatic polymers such as polystyrene; rubber-modified vinyl aromatic polymers such as high impact polystyrenes (HIPS); vinyl aromatic copolymers such as styrene/acrylonitrile or styrene/butadiene copolymers; hydrogenated vinyl aromatic polymers and copolymers such as hydrogenated polystyrene and hydrogenated styrene/butadiene copolymers; alpha-olefin homopolymers such as low density polyethylene, high density polyethylene and polypropylene; linear low density polyethylene (an ethylene/octene-1 copolymer) and other copolymers of ethylene with a copolymerizable, mono-ethylenically unsaturated monomer such as an alpha-olefin having from 3 to 20 carbon atoms; copolymers of propylene with a copolymerizable, mono-ethylenically unsaturated monomer such as an alpha-olefin having from 4 to 20 carbon atoms, copolymers of ethylene with a vinyl aromatic monomer, such as ethylene/styrene interpolymers; ethylene/propylene copolymers; copolymers of ethylene with an alkane such as an ethylene/hexane copolymer; thermoplastic polyurethanes (TPU""s); and blends or mixtures thereof, especially blends of polystyrene and an ethylene/styrene interpolymer.
Other suitable polymers include polyvinyl chloride, polycarbonates, polyamides, polyimides, polyesters such as polyethylene terephthalate, polyester copolymers and modified polyesters such as polyethylene terephthalate-glycol (PETG), phenol-formaldehyde resins, thermoplastic polyurethanes (TPUs), biodegradable polysaccharides such as starch, and polylactic acid polymers and copolymers.
The polymer is preferably polyethylene (PE), polystyrene (PS), polypropylene (PP), a blend of PS and an ethylene/styrene interpolymer (ESI), a blend of ESI and PE, a blend of ESI and PP, a blend of PS, PE and ESI or a blend of ESI with any one or more polyolefin or ethylene/alpha-olefin copolymers, terpolymers or interpolymers produced using a metallocene catalyst or a constrained geometry catalyst (such as The Dow Chemical Company""s INSITE(trademark) catalysts, INSITE is a trademark of The Dow Chemical Company).
Additional additives, such as those commonly used in preparing polymeric foam, can be included in the foamable composition. Additional additive may include pigments, viscosity modifiers, flame retardants, infrared blockers (e.g. carbon black and graphite), nucleating agents, permeation modifiers, and extrusion aids. Interestingly, inclusion of nucleating agents is not necessary to prepare polymeric foam using blowing agent compositions of the present invention.
The present invention further relates to polymeric foam comprising a polymer, a MRLB HFC, a LRLB HFC, and a LBA and/or LBC. Typically, a polymeric foam contains residuals of the blowing agent used in its manufacture. However, blowing agents tend to escape from polymeric foam and air tends to permeate into polymeric foam over time. Therefore, preferably characterize a polymeric foam within the timeframe set forth as xe2x80x9cfreshxe2x80x9d, most preferably immediately after manufacture, to ensure blowing agents have not escaped and air has not contaminated the foam. A polymeric foam may further contain additional blowing agents, such as CO2, when they are included in the blowing agent composition used to make the foam. One may identify the presence of blowing agent residuals using standard analytical techniques, such as gas chromatography.
Polymeric foams of the present invention may take any physical configuration known in the art, such as sheet, rod, plank, or coalesced parallel strands and/or sheets. The foam is preferably a plank, more preferably a plank having a cross-section of 30 square centimeters (cm2) or more and a cross-section thickness in a minor dimension of 0.25 inch (6.4 millimeters (mm)) or greater, more preferably 0.375 inch (9.5 mm)or greater, and still more preferably 0.5 inch (12.7 mm) or greater. A polymeric foam having a minor dimension of up to 8 inches (200 mm) is possible. The upper limit for the minor dimension is limited by foaming equipment limitations. Given large enough equipment, a minor dimension above 8 inches (200 mm) is conceivable.
Polymeric foams of the present invention preferably have a density of 10 kilograms per cubic meter (kg/m3) or greater, normally 25 kg/m3 or greater and normally 100 kg/m3 or less, more often 45 kg/m3 or less. Polymeric foams having a density below 10 kg/m3 generally lack a desired structural integrity. Polymeric foams of the present invention may have a density up to, but not including, that of a combination of the polymer and additives used in preparing the foam.
Polymeric foam of the present invention can be open-celled (greater than 20 percent (%) open-celled) or close-celled (less than 20% open-celled), but foam that is less than 10% open-celled is preferable because it generally has a lower thermal conductivity. Determine percent open cell according to ASTM D2856-A. Typically, a polymeric foam of the present invention has a thermal conductivity 60 days after preparation, preferably 90 days after preparation (as determined according to ASTM method C-518-98 using a sample temperature of 24xc2x0 C.) of 35 milliwatt per meter-Kelvin (mW/mxc2x7K) or less, preferably 30 mW/mxc2x7K or less.
Polymeric foams of the present invention have an average cell size greater than 0.05 millimeters (mm), preferably greater than 0.075 mm, more preferably greater than 0.1 mm, and less than 2 mm, preferably less than 1.2 mm. Determine average cell size using ATSM method D3576 with the following modifications: (1) image a foam using optical or electron microscopy rather than projecting the image on a screen; and (2) scribe a line of known length that spans greater than 15 cells rather than scribing a 30 mm line.

Blowing agent compositions containing hydrofluorocarbons and a low-boiling alcohol and/or low-boiling carbonyl compound


The present invention provides a data processing system and a data collection method by which measurement data can be read in and transmitted easily, without connecting a terminal for transmitting data with various types of measurement apparatuses, and further provides a measurement apparatus to be used for the data processing system and the data collection method. The data processing system at least uses: a measurement apparatus (10) provided with a display screen (13); a terminal (20); and a server (30). The measurement apparatus (10) includes: a measurement portion for obtaining measurement data; a code transforming portion for transforming the measurement data into a bar code, a two-dimensional code (8) or a composite code; and a display portion for displaying the code on the display screen. The terminal (20) includes; an image pickup portion for picking up an image on the display screen (13) that displays the code; an analysis portion for generating measurement data for transmission by analyzing the code that is picked up; and a transmission portion for transmitting, to the server (30), the measurement data for transmission. The server includes a memory portion for storing the transmitted measurement data for transmission.

Since patients who suffer from diabetes usually are required to know their own blood glucose levels, portable blood glucose measurement apparatuses that can be carried easily has been used recently. Such a portable blood glucose measurement apparatus is provided with a storage medium for storing measurement data. Thus, a doctor can read out the measurement data from the storage medium of the blood glucose measurement apparatus, and can provide appropriate remedies and advice to the patient, based on the thus read-out measurement data.
Moreover, it is a burden for the patient to visit a medical institution often in order to disclose his/her measurement data to the doctor. Thus, a system for enabling the patient to transmit his/her measurement data to a server of the medical institution via the internet has been utilized recently (for example, see Patent documents 1 to 3).
According to this system, a patient can transmit his/her measurement data to the server immediately, by using a communication equipment such as a mobile phone and a personal computer (hereinafter, called a "PC"). Moreover, the doctor can know the condition of the patient by accessing the server that stores the measurement data, by using PC or the like. Furthermore, the patient can receive advice by e-mails or the like from the doctor.
Such a system using the internet can be applied not only to blood glucose measurement apparatuses but also to other apparatuses, and thus it is considered that the application of the system will become widespread in the future. Examples of the other apparatuses include blood pressure measurement apparatuses, heart rate measurement apparatuses, urinary constituent measurement (urinary analysis) apparatuses, electrocardiogram measurement apparatuses, passometers and the like.
Patent document 1: JP 2002-368904 A
Patent document 2: JP 2002-368907 A
Patent document 3: WO 01/088764

Data processing apparatus, measurement apparatus and data collection method