The present invention provides a coated cellulosic web product and coating composition which provides enhanced toner adhesion for documents printed using noncontact printing devices such as ion deposition printers. The toner adhesion enhancing coated cellulosic product and composition comprises a cellulosic web having first and second major surfaces with at least one of the major surfaces having coated thereon a layer of a polymeric toner receptor. The polymeric toner receptor layer preferably also includes an electrolyte to adjust the electrical conductivity of the cellulosic web to have a volume resistivity of between about 5.0.times.10.sup.9 and 1.0.times.10.sup.12 ohm cm. The toner receptor layer is applied at a coating weight of from about 0.3 to about 2.0 lb/ream. The invention provides printed documents which can withstand the normal automated handling operations commonly encountered by business documents such as checks, other MICR coded documents, bar coded documents, and the like without the flaking off or removal of the toner from the document. Further, documents printed on substrates utilizing the coating composition of the present invention have been found to have increased resistance to intentional defacement or alteration of printed information.

This invention relates to an adhesion enhancing coating and coated paper for pressure fixed toner particles, and more particularly to a coating and coated paper for use in ion deposition printing applications which provides improved adhesion of the toner particles to the printed product produced.
Business forms, labels, bar codes, and security documents are printed on a wide variety of commercial printing devices. Traditional mechanical impact printers have been used in the past for many of these applications, especially in the imprinting of information on security documents such as checks. The mechanical impact produced by the printers, whether based on formed characters or dot matrix, generally provides information which adheres quite well to the underlying paper document. However, such mechanical impact printers have limited speed, high noise levels, and high costs for parts and maintenance.
With the advance of microcomputer technology, a number of faster printing methods have been developed to take advantage of the high-speed printing output which is now possible. Recently developed nonimpact printers are fast, quiet, and potentially more reliable because of fewer moving parts. Ion deposition printers are one class of these newer nonimpact printers. Such printers operate by directing a computer-controlled stream of ions in a specific pattern onto an image cylinder or drum to form a latent image.
As the image cylinder is rotated, toner particles from a toner cartridge are deposited on the image areas on the cylinder and held there by the charged ions. As the image cylinder continues to rotate, the now visible toner image on the cylinder is then transferred to a paper web which has the correct level of conductivity required. Typically, a solid roller is positioned opposite the image cylinder and exerts pressure on the toner and web to simultaneously transfer and fix the toner to the web.
Descriptions of noncontact printers such as ion deposition printers, the toners used therein, and the papers used for printing on them are known. See, for example, "The evolution of Toning Technology: Past, Present, and Future", Fourth Annual Guide to Ribbons and Toner, Product Overview and Industry Directory published by Datek Information Services, Inc.(1983); "New Papers for New Printers", Chemtech (1986); and "A review of Dry and Liquid Toner Technology", The 1988 Datek Imaging Supplies Manual, all of the disclosures of which are hereby incorporated by reference.
While ion deposition printing is fast and quiet, the process has had significant limitations which have prevented its wide use in printing certain types of documents such as checks, other security documents, labels, and documents having bar code information thereon. These limitations include the inability to achieve satisfactory toner bonding on a large variety of paper products used to make such documents. For example, documents such as checks which contain not only payee and amount information but also MICR coding for automated handling must be able to withstand multiple handling and sorting cycles in high speed automated machinery. If the toner containing information such as MICR or bar coding on the document flakes off or is otherwise removed during such operations, the document will be rejected from the system and will have to be handled manually.
Additionally, because of the lack of strong adherence of toner to paper, documents printed using ion deposition printers are subject to deliberate alteration by counterfeiters, forgers, and the like. For example, check amounts and/or payee information may be readily scraped off and new amounts substituted by the unscrupulous. While it may be possible to employ additional heat fusing steps to adhere the toner particles to paper as the information is printed, this adds an additional stage to the printing process, and care must be taken not to overheat or melt the toner particles or scorch the paper stock.
Still further, papers used in ion deposition printing systems must have a very narrow range of volume and surface resistivities to insure that the toner image is properly transferred from the image cylinder or drum. Such papers are also required to have a relatively high degree of surface smoothness and flatness, a specific range of moisture contents, and resistance to curl. Fabrication of special papers to have these characteristics increases the costs of such papers and their use.
Accordingly, there remains a need in the art for a paper product which provides enhanced toner adhesion for noncontact printed products without the drawbacks of prior art products.

Toner adhesion enhancing coating and coated paper


After a process is performed on a substrate, the in-plane distribution over the substrate is measured. Measured data of the in-plane distribution which is obtained by the measurement is stored. A model formula of the in-plane distribution is calculated from the stored measured data. The measured data is compared with the model formula. A set of parameters of the model formula is calculated, and the calculated parameters are stored as data of the in-plane distribution over the substrate. The measured data includes measurement coordinates over the substrate. The model formula is obtained by modeling the tendency that the in-plane distribution concentrically varies and the tendency that the in-plane distribution varies along a diameter direction.

1. Field of the Invention
The present invention relates to the in-plane uniformity of a semiconductor substrate after a step of processes in the production of a semiconductor device. Specifically, the present invention relates to an in-plane distribution data compression method, an in-plane distribution measurement method, an in-plane distribution optimization method, a process apparatus control method, and a process control method.
2. Description of the Prior Art
Japanese Unexamined Patent Publication No. 2002-184733 discloses a conventional measurement method, which is described herein with reference to the flowchart of FIG. 30.
The measurement method comprises the steps of: performing a first process on a first substrate; and performing a second process on the first substrate or a second substrate, wherein a correlation function for each of in-plane positions is obtained as data of the difference among a plurality of process steps for each of in-plane positions based on the in-plane distribution data for the in-plane position on each of the substrates which are the results of the plurality of processes, the in-plane distribution characteristics of the substrate under a desired process condition is calculated from the correlation function, and the substrate is processed based on the in-plane distribution characteristics.
In the conventional measurement method, one-dimensional measurement is performed to evaluate the distribution from the wafer center to the wafer edge. This has been commonly conducted because of an empirical fact that the in-plane distribution exhibits a substantially concentric distribution. Another reason for the one-dimensional measurement is that, in the case of two-dimensional evaluation, it is necessary to quadratically increase the number of evaluation points as the radius of the substrate increases, which is not required in the one-dimensional evaluation. Thus, in the conventional method, it is necessary to select fine one-dimensional (linear) measurement or rough two-dimensional measurement according to the purpose of measurement. In the case of one-dimensional measurement, even if the in-plane distribution is concentric, the center of concentric circles is off the center of the substrate in many cases. Therefore, accurate evaluation cannot be achieved.
In the case where two-dimensional measurement is carried out for the purpose of accurate evaluation, the measurement has to be conducted at an enormous number of measurement points and accordingly requires an enormous length of time. Furthermore, it is necessary to store an enormous amount of data resulting from the measurement, and therefore, a large capacity storage device is required.

In-plane distribution data compression method, in-plane distribution measurement method, in-plane distribution optimization method, process apparatus control method, and process control method

Matsushita Electric Industrial Co., Ltd.


A microwave oven has a magnetron 26 cooled by a fan 30 which generates a flow of air which is admitted to the oven cavity 10 through an inlet aperture 32, leaving the cavity through an outlet aperture 36. A grill element 22 is located in the upper part of the cavity 10 and a turntable 24 is positioned in the lower part of the cavity 10. Where the air respectively enters and leaves the cavity, thermocouples monitor air inlet (Ti) and air outlet (To) temperatures. After cooking commences, the air inlet and air outlet temperatures are monitored. After a time dependent on the load of the food item being cooked, the plot of air outlet temperature against time crosses the plot of air inlet temperature against time. The crossover point 44 of the air inlet and air outlet temperatures is used to control the remaining cooking time and the duration of energisation of the magnetron and the grill element during the remaining cooking time.

Microwave ovens having radiant heating elements are known. Foodstuffs of different size, shape and dielectric loads produce different air temperature characteristics within the oven. The invention aims to provide a way of making the operation of such ovens automatic by monitoring air temperatures in the oven and using the monitored air temperatures to govern the operation of a microprocessor which controls cooking time and energisation of the magnetron and the radiant heating elements.

Microwave ovens with air inlet and air outlet temperature sensors


The present invention is a multifunctional night vision monocular that is adapted for use by a soldier as a hand-held spotting scope, a helmet mounted scope, a head mounted scope, and a weapon mounted scope depending upon circumstances and the needs of the soldier. The night vision monocular is a self-contained unit capable of carrying its own power source. A universal mount on the bottom of the night vision monocular enables either a helmet mounting adaptor or a weapon sight mount to be quickly added to the monocular. The night vision monocular contains a GEN III image intensifier tube positioned between an objective lens assembly and an eyepiece lens assembly. The housing of the night vision monocular opens in a plane perpendicular to the optical axis, thereby enabling easy access to the various optical elements for repairs, maintenance and replacement. A reduced number of wire leads are used within the night vision monocular thereby reducing manufacturing costs and improving reliability. The image intensifier tube is directly coupled to a circuit board that provides power to the image intensifier tube. As such, the image intensifier tube can be replaced without cutting leads or soldering.

Night vision devices are widely used in the military to provide soldiers, aviators and sailors with the ability to view objects at night or during other low light conditions. However, night vision devices traditionally have been designed to accommodate only one specific application within the military. For example, soldiers in the army are issued night vision goggles that mount to their helmets to enable the soldiers to see at night. Such night vision goggles are exemplified by the AN/PVS-7B night vision goggle system manufactured by ITT Corporation, the assignee herein (ITT Model No. F5001B). The AN/PVS-7B night vision goggle system is a binocular viewing system that mounts to a soldier's head or helmet. Although, such night vision goggle systems are good for allowing a soldier to see in the dark, that same night vision goggle system prevents the soldier from looking through the sight of his/her gun. As a result, the same soldiers that were issued night vision goggles may also require a second night vision system for their weapon. As such, during combat the soldier must remove the night vision goggles and view a target through the night vision sight attached to the soldier's gun. A typical night vision gun sight is exemplified by the AN/PVS-4 night vision weaponsight currently used by the Army. The AN/PVS-4 night vision weaponsight is also manufactured by ITT Corporation,
As can be seen, soldiers operating at night may be required to carry and operate multiple night vision systems. This adds weight and bulk to the soldiers and requires the soldier to be trained in how to properly operate and use more than one night vision system.
It is therefor an objective of the present invention to provide a single night vision device that can selectively be worn on a helmet, worn with a head mount, mounted to a gun or used as a hand held spotting scope, wherein a soldier need only carry a single lightweight night vision device and can use the night vision device as needed.
It is a further object of the present invention to provide a multifunctional night vision device that is lightweight, simple to use, easy to manufacture, easy to repair and easy to maintain at peak performance.


A peritoneal dialysis catheter has annular cuffs at one or more locations along its length. The cuffs are of a woven material to promote tissue ingrowth and thereby anchor the catheter to the body. The catheter has internal channels extending from ports located outside the body to deliver disinfecting fluid to the space between the cuffs and the catheter exterior, preventing infections from reaching the cuffs and reducing the frequency of new implants.

1. Field of the Invention
The present invention relates to surgically implanted catheter and like tubular devices, specifically to catheters or similar live body implantable devices including means for preventing infectious bacteria and other microorganisms from entering and penetrating into the body through the exit wound site of the implanted device. It is even more specifically in its preferred embodiment directed to a catheter for peritoneal dialysis.
Peritoneal dialysis has offered promise for improving the mobility of patients suffering from kidney disease or failure. Like hemodialysis, peritoneal dialysis involves the diffusional removal of waste products in the patient's blood. Instead of removing and treating the blood outside the body, however, dialysate is introduced directly into the peritoneal cavity by a catheter.
The dialysate fluid remains in the peritoneal cavity for a desired period of time as waste products diffuse from the blood across the peritoneum and into the dialysate. When the dialysate reaches chemical equilibrium, it is removed from the body, fresh dialysate is introduced, and the cycle is repeated.
Peritoneal catheters generally involve a tubular body with one or more dialysate ports outside the patient's body which communicate through the tubular body with the peritoneal cavity. A tunnel cavity is surgically created within the abdominal cutaneous and subcutaneous tissues, including the peritoneum. The catheter is then inserted within the cavity and either stitched to body tissues or anchored in place by the use of porous "cuffs" into which tissue growth is facilitated.
Because peritoneal catheters create a tunnel exit site from the body, there exists a potential for the invasion of infectious bacteria and other microorganisms. Furthermore, the movement of the patient's body from ordinary breathing, walking, and other like activities result in small back-and-forth movements, called "pistoning," of the catheter with respect to the cutaneous and subcutaneous body tissues, which aggravates the risk of bacterial invasion.
Many prior attempts to reduce rates of infections for peritoneal dialysis catheters involve the use of "cuffs"--porous segments fitted annularly around the body of the catheter. After implantation, tissue ingrowth into the porous material anchors the catheter to the body, preventing excessive movement. Additionally, the cuffs act as a putative seal against penetration of infectious microorganisms further into the body.
Catheter designs for peritoneal dialysis are known in the art, as are attempts to reduce the risk of bacterial invasion associated with their use. Illustrative are the designs disclosed in U.S. Pat. No. 5,141,499 to Zappacosta; U.S. Pat. No. 5,098,413 to Trudell, et al.; U.S. Pat. No. 5,057,075 to Moncrief et al.; U.S. Pat. No. 5,049,140 to Brenner et al.; U.S. Pat. No. 4,772,269 and U.S. Pat. No. 4,687,471, both to Twardowski; and U.S. Pat. No. 4,623,329 to Drobish et al.
U.S. Pat. No. 5,141,499 to Zappacosta discloses a U-shaped catheter (10) for peritoneal dialysis With two cuffs (18, 30) and a reduced-diameter tube (16) at the exit site from the body to reduce the area for exit-site tunnel infections.
U.S. Pat. No. 5,098,413 to Trudell et al. discloses a catheter (10) for peritoneal dialysis with a bent shape (29) to reduce catheter movement within the body during dialysate introduction and removal. Two cuffs (30) are used to prevent bacteria ingrowth and to hold the catheter (10) in the body.
U.S. Pat. No. 5,057,075 to Moncrief et al. relates to a method of implanting a peritoneal dialysis catheter with two cuffs, one cuff (2) being adjacent the skin and a peritoneal cuff (24) being anterior to the posterior rectus sheath (23).
U.S. Pat. No. 5,049,140 to Brenner et al. discloses elastomeric fittings (12) of cylindrical shape which are impregnated with antimicrobial agents and fit by radial tension as cuffs over the body shaft (14) of a catheter (10).
U.S. Pat. No. 4,772,269 to Twardowski et al. discloses a peritoneal catheter (10) with a bent segment (24) and two porous cuffs (20, 22) to secure the catheter to the abdominal wall.
U.S. Pat. No. 4,687,471 to Twardowski et al. discloses a peritoneal dialysis catheter (15) with a bent segment (24) and two porous cuffs (20, 22) to secure the catheter to the abdominal wall. The device is substantially similar to U.S. Pat. No. 4,772,269 above, of the same inventor, but includes a flange (38, 48) and a bead (44), the flange oriented at an angle to the axis of the catheter tube (12).
U.S. Pat. No. 4,623,329 to Drobish et al. discloses a tube-in-tube catheter, the outer sleeve (10) of which is permeable by diffusion to an antimicrobial agent contained in the annulus (13) between the inner drainage tube (2) and the outer sleeve (10).
Unfortunately, the practice of using cuffs to reduce the risks of bacterial infection in the catheter suffers from several drawbacks. Although cuffs do provide a measure of resistance to bacterial invasion, they do not prevent bacteria from entering the wound at the exit site, nor do they destroy bacteria traveling along the shaft of the catheter toward the cuffs from the exit site. The use of multiple cuffs to provide "staged" protection against invasion has been suggested. It has also been suggested that the cuffs have antimicrobial agents embedded within their pores as discussed in U.S. Pat. No. 5,049,140 to Brenner et al. The effectiveness of such agents, of course, falls off rapidly as their concentration is reduced over time.
Multiple cuffs provide additional rigidity to the catheter, arising from the greater proportion of the total length of the catheter that is subject to tissue ingrowth into the cuffs. They do little to obviate the disadvantages noted above, however. Because of these failures, multiple cuffs can at best only delay the inevitable need for removal of the catheter arising from infection. When this becomes necessary, the greater tissue ingrowth associated with multiple cuffs impedes and complicates the removal and process. In addition, each removal and replacement operation involves additional trauma for patients already suffering from the loss of renal function.
It is therefore an object of this invention to overcome the disadvantages attendant upon the use of cuffs and to prevent indefinitely the onset of infections in peritoneal dialysis and like catheters, while retaining the advantageous properties and functions thereof. It is a further object of the invention to provide an improved catheter for use in peritoneal dialysis which will withstand a much longer indwelling time within the body before removal is required, thus reducing the trauma to the patient.

Catheter or the like with medication injector to prevent infection


Disclosed is a motor, the motor according to an exemplary embodiment of the present disclosure including a rotation shaft having an alignment groove at a distal end of one side from a rotation center, a sensing magnet disposed at the distal end of one side of the rotation shaft by being mounted on the alignment groove of the rotation shaft, a rotor including a magnet coupled to a periphery of the rotation shaft, and a stator including a core wrapping an ambient of the rotor and wound with a coil.

Field of the Disclosure
The present disclosure relates to a motor configured to be used for a dual clutch transmission and the like.
Discussion of the Related Art
In general, a motor is an apparatus converting an electric energy to a rotary power.
The motor includes a rotation shaft, a rotor including a magnet formed on the rotation shaft, and a stator including a coil generating an electromagnetic force in response to a current generated from the coil arranged about the rotor.
Some of the motors where revolution and rotation speed act as important factors may be arranged at a distal end of a rotation shaft with a sensing magnet counting the revolution of the rotation shaft, and a sensing plate calculating an actual revolution of the rotation shaft and rotation speed by detecting a magnetic field generated from the sensing magnet may be arranged at a position opposite to the sensing magnet.
In general, in a case the sensing magnet is arranged at the distal end of the rotation shaft having a flat cross-section, a rotation center of the rotation shaft and a rotation center of the sensing magnet may be adjacently arranged using a jig, but it is difficult to match the rotation center of the rotation shaft and the rotation center of the sensing magnet, even if the jig is used, whereby the sensing magnet is eccentrically rotated from the distal end of the rotation shaft.
Another disadvantage is that the number of assembly processes increases because the sensing magnet is arranged at the distal end of the rotation shaft using the jig.
Particularly, in a case the sensing magnet is eccentrically rotated from the distal end of the rotation shaft, sensing errors on the revolution and rotation speed frequently occur due to difficulty in accurately detecting the magnetic field generated from the sensing magnet.

Motor with shaft integrated sensing magnet


A solid-state element has: a semiconductor layer formed on a substrate, the semiconductor layer having a first layer that corresponds to an emission area of the solid-state element to and a second layer through which current is supplied to the first layer; a light discharge surface through which light emitted from the first layer is externally discharged, the light discharge surface being located on the side of the substrate; and an electrode having a plurality of regions that are of a conductive material and are in ohmic-contact with the second layer.

1. Field of the Invention
This invention relates to a solid-state element and a slid-state device and, particularly, to a solid-state element and a slid-state device that prevent the separation of electrode and the reduction of bonding strength cause by a thermal stress so as to discharge efficiently light from inside of the device.
2. Description of the Related Art
One of conventional solid-state devices is a light emitting device that an LED (light-emitting diode) element as a solid-state element is mounted on a substrate with a lead frame or a wiring pattern. In the light emitting device using the LED element, it is important that light confined inside the LED element is reduced to enhance the external radiation efficiency in order to have a high-brightness or high-output device.
One of the LED elements is a flip-chip type LED element that a semiconductor layer is formed on a transparent substrate such as sapphire and light is discharged from the side of the transparent substrate. The flip-chip type LED element is excellent in the external radiation efficiency since it does not generate an optical loss in the semiconductor layer or a passivation film. In the device mounting, the flip-chip type LED element is flip-chip bonded to a wiring member such as a lead frame inside a reflow furnace at a temperature of 250 to 300° C.
In recent years, as a solder used for the electrical connection of LED element, a lead (Pb) free solder is researched according to considerations to the environment. The Pb free solder has a melting point higher than a Pb containing solder, and therefore a problem is caused that the emission efficiency lowers due to an increase in thermal stress in the flip-chip bonding of LED element.
Japanese patent application laid-open No. 11-150297 (related art 1) discloses a nitride semiconductor light emitting element that its p-electrode is multilayered to improve the emission efficiency of such a flip-chip type LED element.
The nitride semiconductor light emitting element is composed of a first positive electrode that is in ohmic-contact with a p-GaN based semiconductor layer, and a second positive electrode formed on the first positive electrode. The second positive electrode includes a layer of Au or Pt, which is in contact with the first positive electrode, in order to enable a light-emitting layer located directly under the second positive electrode to emit light ([0012] and FIG. 1 of the related art 1).
However, in the above related art 1, there is a problem that the electrode layer may be separated (peeled) from the semiconductor layer due to a difference in thermal expansion coefficient therebetween under high-temperature conditions such as reflowing, since the first and second positive electrodes are formed in continuous planar face.

Solid-state element and solid-state element device


A wireless communication device receives CDMA signals and communicates with remote base stations in site selection diversity transmit (SSDT) mode. During communications with a primary base station, communication state parameters, such as signal to interference ratio (SIR) target values and carrier frequency estimates, are maintained for other base stations of an active set of base stations. The state parameters for communications with a selected base station are available for use after selection of a new base station. In one embodiment, the communication state parameters are used for the selection of a base from the active set.

Code division multiple access (CDMA) is a technique for spread-spectrum digital communications used for many applications, including, for example, mobile communications. In CDMA systems, data signals are combined with a spreading waveform to form a coded signal for transmission. At the receiver, the received signal is combined with a similar spreading waveform to extract the data signals. The technique provides high data capacity by spreading signal energy over a wide bandwidth to increase bandwidth utilization and reduce the effects of narrow band interference. Multipath effects make synchronization more difficult since the wireless channel from a base station to a reception device may have several paths of different time-delays, which may vary due to the movement of the reception device.
Wireless communication devices (e.g., mobile stations), which communicate CDMA signals with remote base stations, often operate in a site selection diversity transmit (SSDT) mode for selection of base stations to communication with. One problem with SSDT mode is that some algorithms, such as power control and frequency estimation algorithms, are unable to quickly adapt to the quick changes in channel conditions that occur when transferring communications from one base station to another. This may result in poor performance, especially after the selection of a new primary base station for communication.
One specific problem area is power control. Mobile stations conventionally implement power control methods to minimize transmission power while maintaining desired performance levels. Conventional power control methods implement a nested loop structure having an outer loop and an inner loop to control transmit power. In the outer loop, the block error rate (BLER) of received data may be monitored and compared to a desired BLER. A signal to interference ratio (SIR) target is then developed for the receiver based on the comparison. In the inner loop, a measured SIR for a received signal is compared to the SIR target. A power control message may then be generated for delivery to the transmitter based on the result of the SIR comparison (e.g., indicating whether transmit power modifications are desirable). A problem with this power control technique (and other similar methods) is that the BLER measurement is relatively slow and, therefore, the SIR target is not able to adapt quickly to changes in channel conditions. As may be appreciated, this may result in poor communication quality after a new base station is selected, until the transmit power may be readjusted.

This patent is subject to a terminal disclaimer.

Wireless communication device and method for communicating in site selection diversity mode


Disclosed are a flame-retardant polycarbonate resin composition comprising, as the essential ingredients, (A) a polycarbonate resin, (B) a specific styrenic resin, and (C) a specific phosphate compound, and its moldings. Containing no halogen, the resin composition and its moldings have good flame retardancy, impact strength, heat-resistant stability, thermal aging resistance, and wet heat resistance.

The present invention relates to a flame-retardant polycarbonate resin composition, precisely to flame-retardant polycarbonate resin composition and moldings having the advantages of impact resistance, in-line heat stability, aging resistance and recyclability. The invention also relates to flame-retardant polycarbonate resin composition and moldings having the advantages of impact resistance, weld strength and good appearance with few weld lines appearing on their surfaces, and capable of being well colored in dark color, and to flame-retardant polycarbonate resin composition and moldings having the advantages of flame retardancy, impact resistance, stable physical properties even in high-temperature and high-humidity atmospheres, and improved recyclability.
As having the advantages of impact resistance, heat resistance and good electric properties, polycarbonate resins have many applications in various fields of, for example, OA (office automation) appliances, information and communication appliances, other electric and electronic appliances for industrial use and household use, automobile parts and building materials. As a rule, polycarbonate resins are self-extinguishable. However, in some fields of typically OA appliances, information and communication appliances, and other electric and electronic appliances for industrial use and household use, required are polycarbonate resins having more improved flame retardancy.
For improving the flame retardancy of polycarbonate resins, halogen-containing flame retardants such as bisphenol A halides and halogenated polycarbonate oligomers have been used along with a flame retardation promoter such as antimony oxide, as their flame-retarding ability is good. However, with the recent tendency toward safety living and environmental protection from discarded and incinerated wastes, the market requires flame retardation with non-halogen flame retardants. As non-halogen flame retardants, phosphorus-containing organic flame retardants, especially organic phosphate compounds may be added to polycarbonate resin compositions, for which various methods have been proposed. Such flame retardants, organic phosphate compounds serve also as a plasticizer, and polycarbonate resin compositions containing them exhibit excellent flame retardancy.
There are some problems with polycarbonate resins in that they require high molding and working temperatures and their melt fluidity is low. Therefore, the molding temperature for polycarbonate resins is relatively high, and when various additives are added to the resins, there occurs still another problem in that the thermal stability of the molding resins is lowered and that the resins could not sufficiently exhibit their properties. On the recent market, moldings for parts and housings of electric and electronic appliances such as duplicators, facsimiles and telephones are required to have complicated shapes with local projections or depressions for, for example, ribs or bosses and to have openings, and are also required to be lightweight and thin-walled from the viewpoint of resources saving. For these reasons, desired are polycarbonate resin compositions having improved melt fluidity, or that is, having improved injection moldability. Various polycarbonate resin compositions having enhanced moldability have heretofore been proposed, to which are added (rubber-modified) styrenic resins in consideration of the physical properties such as impact resistance of the moldings of the compositions.
Compositions of polycarbonate resins to which are added non-halogen phosphate compounds serving as a flame retardant, and those to which are added (rubber-modified) styrenic resins such as acrylonitrile-butadiene-styrene resins (ABS resins), rubber-modified polystyrene resins (HIPS resins) or acrylonitrile-styrene resins (AS resins) for increasing the melt fluidity of the compositions, are known as polymer alloys, and have many applications in the field of various moldings as having good heat resistance and impact resistance.
The ABS resin-containing compositions have improved melt fluidity and impact resistance, but their toughness is often poor. The rubber-modified polystyrene resin (HIPS)-containing compositions also have improved melt fluidity and impact resistance. As compared with the ABS resin-containing compositions, the HIPS-containing compositions have higher toughness if the rubber content of HIPS therein is lowered. HIPS having a lowered rubber content does not lower the toughness and the heat resistance of the resin compositions containing it, but lowers the impact resistance thereof. This is another problem with HIPS.
In order to make polycarbonate resins or their compositions containing a (rubber-modified) styrenic resin and having good melt fluidity have good flame retardancy by adding thereto a phosphate compound, a relatively large amount of the compound must be added to them. Though its flame-retarding ability is good, the phosphate compound often cause some problems when added to polycarbonate resins or their compositions. For example, it is said that phosphate compounds adhere to the molds used for molding resins or resin compositions containing them, and, in addition, phosphate compounds lower the impact strength of resin moldings or yellows them when the resin moldings are kept heated, or left in high-temperature high-humidity atmospheres, or recycled. A composition comprising a polycarbonate resin, a rubber-modified polystyrene resin and a phosphate compound has good flame retardancy and impact resistance, which, however, depends on the rubber content of the rubber-modified polystyrene resin in the composition. When the heat resistance and the toughness of the resin composition is kept on a desired level, the impact resistance thereof is often insufficient. The flame-retardant polycarbonate resin compositions mentioned above are molded in a mode of injection molding, and their moldings are much used for housings of OA appliances, etc. In general, the moldings are colored in dark color such as gray or black, for which is used a colorant comprising, as the essential ingredient, carbon black.
Many of the moldings are thin-walled and have complicated shapes, and they are welded, depending on the shape of the molds used. When welded, the appearance of the welded part is often poor and the weld strength is of ten low. The problem is especially serious with resin compositions comprising a polycarbonate resin and a rubber-modified polystyrene resin and containing a phosphate compound.
When a phosphate compound is added to polycarbonate resins for making them have flame retardancy, it is generally liquid at room temperature or has a low melting point. However, a relatively large amount of such a phosphate compound must be added to polycarbonate resins for making them have flame retardancy, it is often problematic in that the phosphate compound added thereto blooms resin moldings and lowers the heat resistance and the impact resistance of resin moldings. To solve the problem with such a phosphate compound that blooms resin moldings and lower the heat resistance of resin moldings, for example, Japanese Patent Laid-Open No. 228426/1994 discloses a method of combining (A) a polyphenylene-ether resin or a polycarbonate resin, (B) a high-viscosity, alkyl-substituted aromatic phosphate compound having a specific structure, and (C) a triphenyl phosphate.
Japanese Patent Laid-Open No. 179715/1995 discloses a flame-retardant resin composition comprising (A) from 1 to 99 parts by weight of a polycarbonate resin, (B) from 1 to 99 parts by weight of a rubber-reinforced resin, and (C) from 0.1 to 30 parts by weight, relative to 100 parts by weight of (A) and (B), of an organic phosphorus compound having a melting point of not lower than 120xc2x0 C. Japanese Patent Laid-Open No. 12867/1996 discloses a thermoplastic resin composition comprising a resin mixture of from 50 to 98% by weight of (A) an aromatic polycarbonate and from 2 to 50% by weight of (B) an ABS resin and/or (C) an AS resin, and containing from 0.01 to 5 parts by weight, relative to 100 parts by weight of the resin mixture, of (D) a fluororesin and/or a silicone, and from 1 to 40 parts by weight, relative to the same, of (E) a high-melting-point phosphate compound. To solve the problem noted above, these contain a high-viscosity or high-melting-point phosphate compound serving as a flame retardant, and the compound therein is expected to be effective in some degree.
In Japanese Patent Laid-Open No. 100405/1997, proposed is a flame-retardant resin composition comprising (A) a polycarbonate resin, (B) a rubber-reinforced resin such as ABS, (C) a phosphate serving as a flame retardant, and (D) a monomer or oligomer of a phenolic OH-containing polymer substance. However, this is problematic in that bisphenol A for the component (D) therein worsens the physical properties of the resin composition in high-temperature high-humidity atmospheres.
Some examples of compositions comprising a polycarbonate resin, a rubber-modified polystyrene resin and a phosphate compound are known. For example, in Japanese Patent Laid-Open No. 110092/1998, proposed is a composition that contains a rubber-modified polystyrene resin having a rubber polymer content of from 15 to 25% by weight, a volume-average particle size of from 0.3 to 5.0 xcexcm and a gel content of from 15 to 70% by weight, and a block copolymer comprising aromatic vinyl blocks and conjugated diene compound blocks. In Japanese Patent Laid-Open No. 151239/1997, proposed is a composition of good platability, which contains a rubber-reinforced vinylic resin (ABS resin) containing from 1 to 5% by weight of small-size rubber particles having a weight-average particle size of from 0.1 xcexc to less than 0.3 xcexc, and from 3 to 10% by weight of large-size rubber particles having a weight-average particle size of from 0.3 xcexc to less than 2 xcexc. However, these laid-open specifications have no description relating to the colorability of the compositions with pigment, to the appearance of welded part of moldings and to the weld strength of moldings.
Further, for example, Japanese Patent Laid-Open No. 55145/1986 describes a thermoplastic resin composition comprising components of (A) an aromatic polycarbonate resin, (B) an ABS resin, (C) an AS resin, (D) a halogen compound, (E) a phosphate, and (F) a polytetrafluoroethylene. Japanese Patent Laid-Open No. 32154/1990 describes a flame-retardant, high-impact polycarbonate molding composition comprising components of (A) an aromatic polycarbonate resin, (B) an ABS resin, (C) an AS resin, (D) a phosphate, and (E) a polytetrafluoroethylene.
Anyhow, in these proposals, the latitude in using the phosphate compound is limited. When such a specific phosphate compound is selectively used in the resin compositions proposed, it could solve the problem of improving the molding environment in which the resin compositions are molded and the problem of improving the appearance of the resin moldings, but, at present, could not totally solve the problem of improving the dispersibility and the melt kneadability of the resin compositions and the problem of improving the impact strength, the aging resistance, especially the wet heat resistance and the recyclability of the resin moldings.
With the recent tendency toward environmental protection and energy and resources saving, recycling resin moldings is desired. Specifically, in repeated re-melting and re-mixing used resin moldings for recycling them, it is desired that the physical properties of the recycled moldings are degraded little and that the recycled moldings are yellowed little.
Accordingly, also desired are flame-retardant polycarbonate resins that are stable even in high-temperature high-humidity atmospheres, or that is, those highly resistant to hydrolysis. On the other hand, known is a technique of adding an inorganic filler such as talc to flame-retardant polycarbonate resins, for example, in Japanese Patent Laid-Open Nos. 126510/1995 and 48912/1997. In these, the inorganic filler added to flame-retardant polycarbonate resins is for improving the heat resistance and the toughness of the resin moldings, and its amount is generally at least 5% by weight, especially at least 10% by weight to attain the intended object. However, even when about 5% by weight of talc is added to 100 parts by weight of the resin component, it causes a serious problem in that the impact strength of the resin moldings is greatly lowered.
The present invention has been made in consideration of the above-mentioned viewpoints, and includes three aspects. The first aspect of the invention is to add a phosphate compound to a polycarbonate resin to make the resin resistant to flames, and its object is to provide a flame-retardant polycarbonate resin composition having good flame retardancy and capable of being molded into moldings having good impact resistance, good aging resistance including heat resistance and wet heat resistance, and good recyclability, and to provide moldings of the composition. The second aspect of the invention is to add a phosphate compound to a composition comprising a polycarbonate resin and a rubber-modified polystyrene resin to thereby make the resin composition resistant to flames, and its object is to provide a flame-resistant polycarbonate resin composition having good flame retardancy and capable of being molded into moldings having good impact resistance, high weld strength, good appearance and gloss with few weld lines, and good colorability in dark color such as black, dark gray, dark blue and light gray, and to provide moldings of the composition. The third aspect of the invention is to add a phosphate compound to a polycarbonate resin to make the resin resistant to flames, while adding thereto a styrenic resin to improve the moldability of the resin composition, and its object is to provide a polycarbonate resin composition having good flame retardancy and capable of being molded into moldings having good aging resistance including heat resistance and moisture resistance, and having good recyclability in repeated heat cycle of re-melting and re-molding, and to provide moldings of the composition.
We, the present inventors have assiduously studied and, as a result, have completed the present invention including the first to third aspects specifically mentioned below. In the first aspect of the invention, we have assiduously studied how to improve the moldability and the heat resistance of a flame-retardant polycarbonate resin containing, as a flame retardant, a phosphate compound in order that the moldings of the resin composition can be well used in any severe condition. As a result, we have found that, in a polycarbonate resin composition containing, as a flame retardant, a phosphate compound, when the content of a specific component is specifically defined, then the moldability and the heat resistance of the resin composition are improved, and, in addition, the moldings of the composition are deteriorated little and are yellowed little even when used under heat or in high-temperature high-humidity atmospheres and even when recycled in repeated heat cycle of re-melting and re-molding them. On the basis of these findings, we have completed the first aspect of the invention.
Specifically, the first aspect of the invention includes the following (1) to (7):
(1) A flame-retardant polycarbonate resin composition comprising (A) from 5 to 100% by weight of a polycarbonate resin and (B) from 0 to 95% by weight of a styrenic resin, and (C) from 1 to 30 parts by weight, relative to 100 parts by weight of the resin, of a phosphate compound, in which the amount of phenols extracted in Soxhlet extraction with a solvent of acetone is at most 300 ppm.
(2) The flame-retardant polycarbonate resin composition of above (1), wherein the terminal hydroxyl ratio to the terminals of the polycarbonate resin falls between 0.5 and 20 mol %.
(3) The flame-retardant polycarbonate resin composition of above (1) or (2), wherein the resin comprises from 20 to 95% by weight of the polycarbonate resin (A) and from 5 to 80% by weight of a rubber-modified styrenic resin for the component (B).
(4) The flame-retardant polycarbonate resin composition of any of above (1) to (3), which further contains (D) from 0.02 to 5 parts by weight, relative to 100 parts by weight of the resin (A) and (B), of a fluoro-olefin resin.
(5) The flame-retardant polycarbonate resin composition of any of above (1) to (4), which further contains (E) from 0.2 to 30 parts by weight, relative to 100 parts by weight of the resin (A) and (B), of a core/shell type, grafted rubber-like elastomer.
(6) A molding of the flame-retardant polycarbonate resin composition of any of above (1) to (5).
(7) An injection molding of the flame-retardant polycarbonate resin composition of any of above (1) to (5), for housings or parts of electric and electronic appliances.
In the second aspect of the invention, we have assiduously studied how to improve the moldability, the impact resistance, the appearance and the weldablity of a flame-retardant polycarbonate resin composition containing, as a fluidity improver, a rubber-modified polystyrene resin and containing, as a flame retardant, a phosphate compound. As a result, we have found that, in a polycarbonate resin composition containing a rubber-modified polystyrene resin and containing, as a flame retardant, a phosphate compound, when the property and the morphology of the rubber-modified polystyrene are specifically defined, then the moldability of the resin composition is well improved not lowering the toughness of the moldings of the composition, and, in addition, the impact resistance of the moldings is also improved, the moldings are easily colored in dark color, and the weldability and the surface gloss of the moldings are good. On the basis of these findings, we have completed the second aspect of the invention.
Specifically, the second aspect of the invention includes the following (1) to (6):
(1) A flame-retardant polycarbonate resin composition comprising (A) from 60 to 99% by weight of a polycarbonate resin and (B) from 1 to 40% by weight of a rubber-modified polystyrene resin, and (C) from 1 to 30 parts by weight, relative to 100 parts by weight of the resin, of a phosphate compound, in which the rubber-modified polystyrene resin (B) has (a) an area-average rubber particle size of from 0.1 to 2.5 xcexcm, (b) a swelling index of from 10 to 20, and (c) a gel content of from 15 to 25% by weight.
(2) The flame-retardant polycarbonate resin composition of above (1), which further contains (D) from 0.02 to 5 parts by weight, relative to 100 parts by weight of the resin (A) and (B), of a fluoro-olefin resin.
(3) The flame-retardant polycarbonate resin composition of above (1) or (2), which further contains (E) from 0.2 to 30 parts by weight, relative to 100 parts by weight of the resin (A) and (B), of a core/shell type, grafted rubber-like elastomer.
(4) A molding of the flame-retardant polycarbonate resin composition of any of above (1) to (3).
(5) An injection molding of the flame-retardant polycarbonate resin composition of any of above (1) to (3), for housings or parts of electric and electronic appliances.
(6) The molding of above (4) or (5), of which the L value of the surface is at most 80.
In the third aspect of the invention, we have assiduously studied how to improve the moldability, the heat resistance and the moisture resistance of a flame-retardant polycarbonate composition containing, as a flame retardant, a phosphate compound. As a result, we have found that, when a specifically defined amount of a specific additive is selectively added to a resin composition comprising a polycarbonate resin and a styrenic resin, with adding a phosphate compound thereto, then the impact resistance, the aging resistance and the recyclability of the resin composition and its moldings are well improved, not lowering the flame retardancy the composition and moldings. On the basis of these findings, we have completed the third aspect of the invention.
Specifically, the third aspect of the invention includes the following (1) to (7):
(1) A flame-retardant polycarbonate resin composition comprising (A) from 70 to 95% by weight of a polycarbonate resin and (B) from 5 to 30% by weight of a styrenic resin, and (C) from 2 to 20 parts by weight, relative to 100 parts by weight of the resin, of a phosphate compound and (D) from 0.1 to 4 parts, relative to the same, of a tabular inorganic filler.
(2) The flame-retardant polycarbonate resin composition of above (1), wherein the tabular inorganic filler is talc having a mean particle size of from 0.2 to 2 xcexcm.
(3) The flame-retardant polycarbonate resin composition of above (1) or (2), wherein the phosphate compound is a condensed phosphate compound having a resorcinol or hydroquinone structure and a phenylene-ether structure.
(4) The flame-retardant polycarbonate resin composition of any of above (1) to (3), which further contains (E) from 0.05 to 5 parts by weight, relative to 100 parts by weight of the resin (A) and (B), of a fluoro-olefin resin.
(5) The flame-retardant polycarbonate resin composition of any of above (1) to (4), which further contains (F) from 1 to 30 parts by weight, relative to 100 parts by weight of the resin (A) and (B), of a core/shell type, grafted rubber-like elastomer.
(6) A molding of the flame-retardant polycarbonate resin composition of any of above (1) to (5).
(7) An injection molding of the flame-retardant polycarbonate resin composition of any of above (1) to (5), for housings or parts of electric and electronic appliances.
Embodiments of the invention are described below, in order from the first aspect to the others.
First Aspect of the Invention:
The constituent components (A) to (C) of the flame-retardant polycarbonate resin composition of the first aspect of the invention (this will be simply referred to as xe2x80x9cthe inventionxe2x80x9d in this section) are described.
(A) Polycarbonate Resin (PC):
The polycarbonate resin (PC) serving as the component (A) in the flame-retardant polycarbonate resin composition of the invention is not specifically defined, and may be any and every one known in the art. Generally used herein are aromatic polycarbonates to be produced from diphenols and carbonate precursors. For example, herein used are polycarbonates as produced by reacting a diphenol and a carbonate precursor in a solution method or in a melt method, such as those produced through reaction of a diphenol and phosgene or through interesterification of a diphenol and a diphenyl carbonate.
Various diphenols are usable, typically including 2,2-bis(4-hydroxyphenyl)propane [bisphenol A], bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 4,4xe2x80x2-dihydroxydiphenyl, bis(4-hydroxyphenyl)cycloalkanes, bis(4-hydroxyphenyl) oxide, bis(4-hydroxyphenyl) sulfide, bis(4-hydroxyphenyl) sulfone, bis(4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) ether, and bis (4-hydroxyphenyl) ketone.
As the diphenols for use herein, preferred are bis(hydroxyphenyl)alkanes, especially those consisting essentially of bisphenol A. The carbonate precursors for use in the invention include, for example, carbonyl halides, carbonyl esters, and haloformates, concretely, phosgene, diphenol dihaloformates, diphenyl carbonate, dimethyl carbonate, and diethyl carbonate. Other diphenols such as hydroquinone, resorcinol, and catechol are also usable in the invention. The diphenols mentioned herein may be used either singly or as combined.
The polycarbonate resin may have a branched structure, for which the branching agent includes, for example, 1,1,1-tris(4-hydroxyphenyl)ethane, xcex1,xcex1xe2x80x2,xcex1xe2x80x3-tris(4-hyroxyphenyl)-1,3,5-triisopropylbenzene, phloroglucine, trimellitic acid, and isatin-bis (o-cresol). For controlling the molecular weight of the polycarbonate resin, for example, employable are phenol, p-t-butylphenol, p-t-octylphenol, and p-cumylphenol.
The polycarbonate resin for use in the invention may be a copolymer having polycarbonate segments and polyorganosiloxane segments, or a polycarbonate resin containing a copolymer of that type. It may also be a polyester-polycarbonate resin to be produced through polymerization of a polycarbonate in the presence of an ester precursor, such as a difunctional carboxylic acid (e.g., terephthalic acid) or its ester-forming derivative. Various types of different polycarbonate resins may be mixed to give mixed polycarbonate resins for use in the invention. Preferably, the polycarbonate resin for the component (A) in the invention does not substantially contain a halogen in the structure. In view of its mechanical strength and moldability, the polycarbonate resin preferably has a viscosity-average molecular weight of from 10,000 to 100,000, more preferably from 11,000 to 40,000, even more preferably from 12,000 to 25,000.
Also preferably, the terminal hydroxyl ratio to the terminals of the polycarbonate resin for use in the invention is at least 0.5 mol %, more preferably from 0.5 to 20 mol %. The hydroxyl group in the polycarbonate resin contributes toward improving the miscibility of the polycarbonate resin with the phosphate compound in the resin composition, especially improving the miscibility of the polycarbonate resin and the styrenic resin with the phosphate compound therein, therefore reducing failed moldings with layer peeling, and improving the physical properties, such as the impact strength, the elongation and the weld strength of the resin moldings. On the other hand, however, the hydroxyl group often has a negative influence on the heat resistance of the resin composition. Accordingly, the terminal hydroxyl ratio to all terminals of the polycarbonate resin preferably falls between 0.5 and 20 mol % from the total viewpoint.
Also preferably, the low-molecular weight component of the polycarbonate resin, which is extracted in Soxhlet extraction with a solvent of acetone, is generally at most 10% by weight. In addition, it is desirable that the halogen content, generally the chlorine content of the polycarbonate resin is small, generally at most 200 ppm, preferably at most 100 ppm. The low-molecular weight component and the chlorine content of the resin can be comprehensively controlled to the desired range by selecting the production method (solution method, melt method) and by controlling the production condition including the condensation condition, and also the washing condition, the pelletizing condition, the drying condition, the melt-kneading condition and the additive formulation.
(B) Styrenic Resin:
The styrenic resin for the component (B) of the flame-retardant polycarbonate resin composition of the invention may be a polymer prepared through polymerization of a monomer or monomer mixture of from 20 to 100% by weight of a monovinylic aromatic monomer such as styrene or xcex1-methylstyrene, from 0 to 60% by weight of a vinyl cyanide-type monomer such as acrylonitrile or methacrylonitrile, and from 0 to 50% by weight of any other vinylic comonomer copolymerizable with those monomers, such as maleimide or methyl (meth)acrylate. The polymer includes, for example, polystyrenes (GPPS), and acrylonitrile-styrene copolymers (AS resins).
For the styrenic resin, preferred are rubber-modified styrenic resins. The rubber-modified styrenic resins are preferably high-impact styrenic resins produced through grafting polymerization of rubber with at least styrenic monomers. The rubber-modified styrenic resins include, for example, high-impact polystyrenes (HIPS) produced through polymerization of rubber such as polybutadiene with styrene; ABS resins produced through polymerization of polybutadiene with acrylonitrile and styrene; MBS resins produced through polymerization of polybutadiene with methyl methacrylate and styrene. These rubber-modified styrenic resins may be combined, or may be mixed with other styrenic resins not modified with rubber such as those mentioned above, and the resin mixtures may be used in the invention.
In the rubber-modified styrenic resins, the amount of rubber to modify them may fall, for example, between 2 and 50% by weight, but preferably between 5 and 30% by weight, more preferably between 5 and 15% by weight. If the rubber content is smaller than 2% by weight, the resin composition will have poor impact resistance. If, on the other hand, it is larger than 50% by weight, the thermal stability of the resin composition will be lowered, and the melt fluidity thereof will be also lowered. If so, the resin composition will be unfavorably gelled or yellowed. Specific examples of rubber for use herein include polybutadiene, acrylate and/or methacrylate-having rubber-like polymers, styrene-butadiene-styrene (SBS) rubber, styrene-butadiene rubber (SBR), butadiene-acrylic rubber, isoprene rubber, isoprene-styrene rubber, isoprene-acrylic rubber, and ethylene-propylene rubber. Of those, especially preferred is polybutadiene. The polybutadiene usable herein may be any of low-cis polybutadiene (for example, having from 1 to 30 mol % of 1,2-vinyl bonds and from 30 to 42 mol % of 1,4-cis bonds) or high-cis polybutadiene (for example, having at most 20 mol % of 1,2-vinyl bonds and at least 78 mol % of 1,4-cis bonds), and even their mixtures.
(C) Phosphate Compound:
The phosphate compound is preferably a non-halogen phosphate compound, for example, represented by the following formula (1):
wherein R1, R2, R3and R4 each independently represent a hydrogen atom or an organic group; X represents a divalent or higher polyvalent organic group; p is 0 or 1; q is an integer of 1 or larger; and r is an integer of 0 or larger.
In formula (I), the organic group includes, for example, substituted or unsubstituted alkyl, cycloalkyl and aryl groups. The substituents for the substituted groups include, for example, alkyl groups, alkoxy groups, aryl groups, aryloxy groups, and arylthio groups. These substituents may be combined to give arylalkoxyalkyl groups, or may be bonded, for example, via oxygen, nitrogen or sulfur atom to give arylsulfonylaryl groups.
In formula (I), the divalent or higher polyvalent organic group X is meant to include divalent or higher polyvalent groups to be derived from the organic groups as above by removing one or more hydrogen atoms bonding to carbon atoms. For example, it includes alkylene groups, (substituted) phenylene groups, and groups as derived from bisphenols of polycyclic phenols.
Preferred are groups derived from bisphenol A, hydroquinone, resorcinol, diphenylmethane, dihydroxydiphenyl, and dihydroxynaphthalene.
The phosphate compound may be a monomer, an oligomer, a polymer or their mixture. Concretely, it includes, for example, trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate, tributoxyethyl phosphate, triphenyl phosphate, tricresyl phosphate, cresyldiphenyl phosphate, octyldiphenyl phosphate, tri(2-ethylhexyl) phosphate, diisopropylphenyl phosphate, trixylenyl phosphate, tris(isopropylphenyl) phosphate, tributyl phosphate, bisphenol A bisphosphate, hydroquinone bisphosphate, resorcinol bisphosphate, resorcinol-diphenyl phosphate, trihydroxybenzene triphsophate, and cresyldiphenyl phosphate, and their substituted derivatives and condensed derivatives.
Commercially-available, non-halogen phosphates that are preferably used for the component (C) of the flame-retardant polycarbonate resin composition of the invention are, for example, TPP [triphenyl phosphate], TXP [trixylenyl phosphate], CR-733S [resorcinol bis(diphenyl phosphate)], PX200 [1,3-phenylene-tetrakis(2,6-dimethylphenyl) phosphate], PX201 [1,4-phenylene-tetrakis(2,6-dimethylphenyl) phosphate], and PX202 [4,4xe2x80x2-biphenylene-tetrakis(2,6-dimethylphenyl) phosphate], all from Daihachi Chemical Industry.
The formulation of the components (A) to (C) in the invention is described. In the invention, the styrenic resin of the component (B) has no direct relation to the flame retardancy of the resin composition, and may be in the resin composition when the melt fluidity of the polycarbonate resin therein must be improved. The blend ratio of the polycarbonate resin (A) to the styrenic resin (B) may be generally such that the polycarbonate resin (A) accounts for from 5 to 100% by weight, preferably from 30 to 95% by weight, more preferably from 60 to 95% by weight, and the styrenic resin (B) accounts for from 0 to 95% by weight, preferably from 5 to 70% by weight, more preferably from 5 to 40% by weight. If the polycarbonate resin content for the component (A) is smaller than 5% by weight, the heat resistance and the mechanical strength of the moldings of the composition will be low; and if the styrenic resin content for the component (B) is smaller than 5% by weight, the moldability of the composition may be poor. Especially preferably, the styrenic resin content is smaller than 40% by weight, as the flame retardancy level of the resin composition increases from the class HB to the class V-2 in UL94. In this case, the styrenic resin (B) is preferably the above-mentioned acrylonitrile-styrene copolymer or rubber-modified styrenic resin, more preferably, the rubber-modified styrenic resin. The rubber component of the polycarbonate resin composition containing the rubber-modified styrenic resin is preferably at most 15% by weight, more preferably at most 10% by weight. The blend ratio of the resins may be suitably determined, depending on the molecular weight of the polycarbonate resin, the type, the molecular weight, the melt index and the rubber content of the styrenic resin, and the use, the size and the thickness of the resin moldings.
The phosphate content for the component (C) falls between 1 and 30 parts by weight, preferably between 2 and 25 parts by weight, more preferably between 3 and 20 parts by weight, relative to 100 parts by weight of the resin of (A) and (B). If the phosphate content is smaller than 1 part by weight, the intended flame retardancy is difficult to attain; but if larger than 30 parts by weight, the heat resistance and the impact strength of the resin moldings will lower. Therefore, the phosphate content is determined in consideration of the desired flame retardancy of the resin moldings, comprehensively depending on the type of the phosphate compound and on the content of any other additive of rubber-like elastomer and inorganic filler.
The flame-retardant polycarbonate resin composition of the invention basically comprises the components (A) to (C). If desired, however, an additional component (D), fluoro-olefin resin may be added to the flame-retardant polycarbonate resin composition, for preventing resin melts from dropping when the composition is fired. The fluoro-olefin resin (D) is generally a polymer or copolymer having a fluoro-ethylenic structure, for example, including difluoroethylene polymers, tetrafluoroethylene polymers, tetrafluoroethylene-hexafluoropropylene copolymers, and copolymers of tetrafluoroethylene with fluorine-free ethylenic monomers.
Preferred is polytetrafluoroethylene (PTFE) desirably having a mean molecular weight of at least 500,000, more desirably from 500,000 to 10,000,000. Any and every type of polytetrafluoroethylene known at present in the art is usable in the invention.
More preferred for use herein is polytetrafluoroethylene having the ability to form fibrils, as its property of preventing resin melts from dropping is better. The fibril-forming polytetrafluoroethylene (PTFE) is not specifically defined, but preferred is PTFE of Type 3 defined in the ASTM Standard. Specific examples of PTFE of Type 3 include Teflon 6-J (from Mitsui-DuPont Fluorochemical), Polyflon D-1, Polyflon F-103, Polyflon F201 (all from Daikin Industry), and CD-076 (from Asahi ICI Fluoropolymers).
Others except PTFE of Type 3 are also employable herein, including, for example, Argoflon F5 (from Montefluos), Polyflon MPA and Polyflon FA-100 (both from Daikin Industry). These polytetrafluoroethylenes (PTFES) may be used either singly or as combined. The fibril-forming polytetrafluoroethylenes (PTFES) as above may be obtained, for example, by polymerizing tetrafluoroethylene in an aqueous solvent in the presence of sodium, potassium or ammonium peroxydisulfide, under a pressure of from 1 to 100 psi, at a temperature falling between 0 and 200xc2x0 C., preferably between 20 and 100xc2x0 C.
The fluoro-olefin resin content of the resin composition falls between 0.02 and 5 parts by weight, preferably between 0.05 and 2 parts by weight, relative to 100 parts by weight of the resin of (A) and (B) in the composition. If the fluoro-olefin resin content is smaller than 0.02 parts by weight, the resin melt-dropping preventing ability of the composition will be not enough for the intended flame retardancy of the composition. However, even if the content is larger than 5 parts by weight, the effect of the fluoro-olefin resin added could not be augmented any more, and such a large amount of the fluoro-olefin resin, if added to the composition, will have some negative influences on the impact resistance and the outward appearance of the moldings of the composition. Therefore, the amount of the fluoro-olefin resin to be added to the composition may be suitably determined, depending on the necessary flame retardancy of the moldings of the composition, for example, based on V-0, V-1 or V-2 in UL-94, and depending on the amount of the other constituent components.
The flame-retardant polycarbonate resin composition of the invention may further contain a core/shell-type, grafted rubber-like elastomer (E) which further enhances the impact resistance of the moldings of the composition. The grafted rubber-like elastomer content of the composition falls between 0.2 and 30 parts by weight, preferably between 0.5 and 10 parts by weight, relative to 100 parts by weight of the resin of (A) and (B) in the composition. The grafted rubber-like elastomer content shall be suitably and comprehensively determined in consideration of the necessary properties including impact resistance, heat resistance and toughness of the intended moldings of the composition.
The core/shell-type, grafted rubber-like elastomer has a two-layered structure composed of a core and a shell, in which the core is of a flexible rubber material and the shell that covers the core is of a hard resin material. As a whole, the elastomer itself is powdery or granular. After blended with a polycarbonate resin in melt, the grafted rubber-like elastomer of that type mostly keeps its original powdery or granular condition. Since the grafted rubber-like elastomer keeps its original powdery or granular condition after having been blended with the resin melt, it is effective for preventing the moldings of the resin composition from being troubled by surface layer peeling.
Known are various core/shell-type, grafted rubber-like elastomers that are usable herein. Commercially-available products of such elastomers include, for example, Hiblen B621 (from Nippon Zeon), KM-330 (from Rohm and Haas), Metablen W529, Metablen S2001, Metablen C223, Metablen B621 (all from Mitsubishi Rayon).
Above all, preferred are those to be produced through polymerization of one or more vinylic monomers in the presence of a rubber-like polymer as obtained from monomers of essentially alkyl acrylates or alkyl methacrylates and dimethylsiloxane. In the alkyl acrylates and alkyl methacrylates, the alkyl group preferably has from 2 to 10 carbon atoms. Concretely, the acrylates and methacrylates include, for example, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, and n-octyl methacrylate. One example of the rubber-like elastomers that are obtained from monomers of essentially those alkyl (meth)acrylates is a polymer to be prepared through reaction of at least 70% by weight of the alkyl (meth)acrylates with at most 30% by weight of other copolymerizable vinylic monomers such as methyl methacrylate, acrylonitrile, vinyl acetate, and styrene. To prepare the polymer, a polyfunctional monomer serving as a crosslinking agent, such as divinylbenzene, ethylene dimethacrylate, triallyl cyanurate, or triallyl isocyanurate, may be added to the polymerization system.
The vinylic monomers to be polymerized in the presence of a rubber-like polymer include, for example, aromatic vinyl compounds such as styrene, a-methylstyrene; acrylates such as methyl acrylate, ethyl acrylate; and methacrylates such as methyl methacrylate, ethyl methacrylate. One or more these monomers may be (co)polymerized, as combined, or may be copolymerized with any other vinylic monomers such as vinyl cyanide compounds (e.g., acrylonitrile, methacrylonitrile), and vinyl esters (e.g., vinyl acetate, vinyl propionate). The (co)polymerization may be effected in any known method of, for example, bulk polymerization, suspension polymerization, or emulsion polymerization. Preferred is emulsion polymerization.
It is desirable that the core/shell-type, grafted rubber-like elastomers thus produced in the manner mentioned above contain at least 20% by weight of the rubber-like polymer moiety. Typical examples of the core/shell-type, grafted rubber-like elastomers are MAS resin elastomers such as graft copolymers of styrene and methyl methacrylate with from 60 to 80% by weight of n-butyl acrylate. Other examples are composite rubber grafted copolymers to be prepared through graft copolymerization of a composite rubber with at least one vinylic monomer, in which the composite rubber comprises from 5 to 95% by weight of a polysiloxane rubber component and from 5 to 95% by weight of a polyacryl(meth)acrylate rubber component as so entangled that they are not separated from each other, and has a mean particle size of from 0.01 to 1 xcexcm or so. The composite rubber grafted copolymers are better than single rubber grafted copolymers, as their effect of improving the impact resistance of resin moldings is higher than that of the latter, single rubber grafted copolymers. Commercial products of such composite rubber grafted copolymers are available, for example, Metablen S-2001 from Mitsubishi Rayon.
The flame-retardant polycarbonate resin composition of the invention is characterized in that, when the composition, generally ground pellets of the composition are subjected to Soxhlet extraction with a solvent of acetone, the phenol content of the extract is at most 300 ppm, preferably at most 200 ppm of the total amount of the composition. If the phenol content of the extract is larger than 300 ppm, it is unfavorable since the in-line heat stability, the thermal aging resistance, the wet heat resistance and the recyclability of the resin moldings are poor, or that is, the physical properties of the resin moldings, especially the thermal stability thereof are worsened, and the resin moldings often yellow.
The phenols include all derived from the polycarbonate resin, the phosphate compound and other additives constituting the resin composition. Concretely, they will be derived from the starting polycarbonate resin, phosphate compound and styrenic resin, even from the impurities in these starting materials, and also from additives to the composition and from decomposates produced while the resin composition is melted and kneaded under heat, and will be in the final composition, generally in the pellets of the composition, and all such phenols are meant herein.
As so mentioned hereinabove, it is desirable that, in the flame-retardant polycarbonate resin composition of the invention, the terminal hydroxyl ratio to the terminals of the polycarbonate resin is at least 5 mol %, more preferably falling between 0.5 and 20 mol %. It is also desirable that the halogen content, especially the chlorine content of the flame-retardant polycarbonate resin composition of the invention is at most 50 ppm, more preferably at most 30 ppm.
Methods of analyzing the flame-retardant polycarbonate resin composition for the components are mentioned below.
(1) Determination of Phenol Content:
Pellets of a sample of the flame-retardant polycarbonate resin composition to be analyzed are ground, and passed through a 100-mesh metal sieve. 15 g of the powder having passed through the sieve is metered, and put into a cylindrical paper filter No. 84 (28xc3x97100 mm). This is extracted with 300 ml of acetone, while refluxed for 8 hours at a rate of once (20 ml) for 3 to 4 minutes. Acetone is removed from the resulting extract, and the low-molecular weight residue is weighed. This is dissolved in DMF (dimethylfuran), to which is added N,O-bis(trimethylsilyl)acetamide. Then, this is subjected to temperature-programmed GC analysis through which the phenols therein are quantitatively identified. Based on the data of the low-molecular weight component thus quantified, the phenol content of the composition is calculated.
(2) Determination of Terminal Hydroxyl Ratio to all Terminals of Polycarbonate Resin:
A sample of the polycarbonate resin is-analyzed through NMR.
(3) Determination of Halogen Content of Resin Composition:
10 g of dry pellets of a sample of the flame-retardant polycarbonate resin composition to be analyzed are dissolved in 90 g of methylene chloride, to which is added 50 ml of acetone. This is subjected to potentiometric titration in an automatic titrimeter, for which the titration reagent is a 0.005 M silver nitrate/acetone solution.
The flame-retardant polycarbonate resin composition of the invention may contain, in addition to the indispensable components (A) and (C), at least one optional component selected from (B), (D) and (E), and any other additives that are generally added to ordinary thermoplastic resins, if desired. The optional components and additives are for further improving the moldability of the composition and for further improving the impact resistance, the toughness, the outward appearances, the weather resistance and the stiffness of the moldings of the composition. They include, for example, inorganic fillers such as talc, calcium carbonate, glass fibers, carbon fibers; other thermoplastic resins such as polyester resins; and also phenolic, phosphorus-containing or sulfur-containing antioxidants, antistatic agents, polyamide-polyether block copolymers (for permanent static electrification resistance), benzotriazole-type or benzophenone-type UV absorbents, hindered amine-type light stabilizers (weather-proofing agents), microbicides, compatibilizers, and colorants (dyes, pigments). For their amount, the optional components and additives that may be in the flame-retardant polycarbonate resin composition of the invention are not specifically defined, provided that they do not interfere with the properties of the composition.
A method for producing the flame-retardant polycarbonate resin composition of the invention is described. The flame-retardant polycarbonate resin composition of the invention may be produced by mixing and kneading the components (A) and (C) in a predetermined ratio as above, optionally along with any of the optional components (B), (D) and (E) and additives as above in any desired ratio. Formulating and mixing the constituent components into the intended resin composition may be effected in any known manner, for example, by pre-mixing them in an ordinary device, such as a ribbon blender or a drum tumbler, followed by further kneading the resulting pre-mix in a Henschel mixer, a Banbury mixer, a single-screw extruder, a double-screw extruder, a multi-screw extruder, or a cokneader. The temperature at which the components are mixed and kneaded generally falls between 240 and 300xc2x0 C.
Other components than polycarbonate resin and styrenic resin may be previously mixed with polycarbonate resin or styrenic resin or with any other thermoplastic resin to prepare a master batch, and it may be added to the other constituent components. It is necessary that the content of the impurities and the residual solvent in the starting materials for the flame-retardant polycarbonate resin composition of the invention is as small as possible. Regarding the mode of mixing the starting material to prepare the resin composition, it is desirable that the starting materials are melted and kneaded in an extruder having a large L/D, and the resulting melt is taken out from the bed by vacuum suction to thereby remove the residual solvent from the melt; or they are melted and kneaded in a two-stage extruder so that the volatile component having been released from the resulting melt mixture is fully sucked and removed from the melt mixture. As the case may be, a small amount of alcohol or water may be added to the mixing system, and the impurities are removed from the resulting melt mixture along with the vapor of the additive, alcohol or water accompanied by them.
Having been prepared in the manner noted above, the flame-retardant polycarbonate resin composition of the invention may be molded into various moldings in the melt-molding devices as above, or, after it is pelletized, the resulting pellets may be molded into various moldings through injection molding, injection compression molding, extrusion molding, blow molding, pressing, vacuum forming or foaming. Especially preferably, the composition is pelletized in the melt-kneading manner as above, and the resulting pellets are molded into moldings through injection molding or injection compression molding. For injection molding of the composition, employable is a gas-assisted injection molding method so as to prevent shrinkage cavity around the moldings and to reduce the weight of the moldings.
Injection moldings (including those molded in a mode of injection compression molding) of the flame-retardant polycarbonate resin composition of the invention are usable for various housings and parts for electric and electronic appliances, for example, those for OA appliances and information appliances such as duplicators, facsimiles, televisions, radios, tape recorders, video decks, personal computers, printers, telephones and information terminals; and those for other electric and electronic appliances for household use such as microwave ovens and refrigerators. The moldings have still other applications, and are usable, for example, as automobile parts.
The invention is described more concretely with reference to the following Examples and Comparative Examples, which, however, are not intended to restrict the scope of the invention.

Flame-retardant polycarbonate resin composition and molded product


Aspects of the present invention allow the implementation of one or more data pools using portions or sectors of one or more hard disk drives. Aspects of the invention incorporate at least a method and system of implementing the one or more data pools. The method of implementing a data pool using one or more data storage drives may comprise first generating a first partition table and a second partition table, wherein the first partition table is a mirror image of said second partition table. The method further comprises second generating a first pool information block and a second pool information block, wherein the first pool information block is a mirror image of said second pool information block. The system of implementing a data pool using one or more data storage drives may comprise a memory, a software resident in the memory, and a processor capable of executing the software.

As the data storage requirements of a data processing or computing device increases, a user may wish to add one or more additional data storage drives. Unfortunately, adding such data storage drives may be an arduous task. The user may need to disassemble, configure, and re-connect one or more data storage drives in order to accommodate the additional data storage drive(s). Further, the added data storage drives may need to be manually configured by way of a number of tedious steps. In some instances, one or more software applications must be executed in order to adequately partition the added data storage drive(s). Further, the user, in many instances, may desire the added redundancy and throughput provided by mirroring and striping the data storage drives. Often, however, this task may involve a number of complex steps and may be difficult to implement. Hence, as the data storage requirements of a user increase, it becomes increasingly important to be able to quickly and efficiently add data storage capacity that suits the user's needs.
The limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with some aspects of the present invention as set forth in the remainder of the present application with reference to the drawings.

Method and system of data storage capacity allocation and management using one or more data storage drives


An electrode structure for use in a sealed arc lamp is described. The electrode structure includes a tungsten containing rod surrounded by a block of sintered tungsten containing powder. The block may be impregnated with a thermally conductive material such as copper, silver or braze, and may have a high thermal emissivity surface.

1. Field of the Invention
This invention relates to electrode structures. The invention has particular, although not exclusive, relevance to electrode structures for use in sealed arc lamps which incorporate an ionizable gas (for example xenon), to enable an arc to be established between two electrode structures in the lamp.
2. Description of the Related Art
As a result of the high temperatures involved in the formation of an arc, sealed arc lamps generally use tungsten electrodes. Such electrodes often contain small amounts of additional elements in order to modify the properties of the electrodes. For example by the addition of thorium oxide, the work function of the electrode may be reduced thus promoting arc ignition in the lamp. Normally the electrode is machined by diamond grinding from a solid tungsten rod or bar, the surface of the electrode often being profiled so as to increase the effective surface area of the electrode thereby facilitating radiative cooling of the electrode. However, this machining is expensive and, in the case where thorium oxide has been added to reduce the work function, is a hazardous procedure.
It is an object of the present invention to provide an electrode structure wherein these problems are at least alleviated, and in which the effective surface area of the electrode structure may be increased over that which has previously been possible.

Electrode structure including a rod comprising refractory metal and having a greater thermal conductivity material


A soft contact lens comprising a silicone-hydrogel made by curing a reaction mixture comprising a silicone-containing monomer.

A hydrogel is a hydrated cross-linked polymeric system that contains water in an equilibrium state. Hydrogels typically are oxygen permeable and biocompatible, making them a preferred material for producing biomedical devices and in particular contact or intraocular lenses.
Conventional hydrogels are prepared from monomeric mixtures predominantly containing hydrophilic monomers, such as 2-hydroxyethyl methacrylate (HEMA) or N-vinyl pyrrolidone (NVP). U.S. Pat. Nos. 4,495,313; 4,889,664 and 5,039,459 disclose the formation of conventional hydrogels. Oxygen permeability of these conventional hydrogel materials relates to the water content of the materials, and is typically below 20-30 barrers. For contact lenses made of the conventional hydrogel materials, that level of oxygen permeability is suitable for short-term wear of the contact lenses; however, that level of oxygen permeability may be insufficient to maintain a healthy cornea during long-term wear of contact lenses (e.g. 30 days without removal). Therefore, efforts have been made and continue to be made to increase the oxygen permeability of conventional hydrogels.
One known way to increase the oxygen permeability of the hydrogels is to add silicone-containing monomers to the hydrogel formulations, thereby making silicone hydrogels. Silicone-containing polymers generally have higher oxygen permeabilities than conventional hydrogels. Silicone hydrogels have been prepared by polymerizing mixtures containing at least one silicone-containing monomer and at least one hydrophilic monomer. Either the silicone-containing monomer or the hydrophilic monomer may function as a crosslinking agent (a crosslinking agent is a monomer having multiple polymerizable functionalities) or a separate crosslinking agent may be employed. The formation of silicone hydrogels has been disclosed in U.S. Pat. Nos. 4,954,587; 5,010,141; 5,079,319; 5,115,056; 5,260,000; 5,336,797; 5,358,995; 5,387,632; 5,451,617; and 5,486,579; and WO 96/31792.
U.S. Pat. No. 3,808,178 discloses the formation of copolymers of small silicone-containing monomers and various hydrophilic monomers.
U.S. Pat. No. 5,034,461 describes silicone hydrogels prepared from various combinations of silicone-polyurethane macromers and hydrophilic monomers such as HEMA or N,N-dimethyacrylamide (DMA). The addition of methacryloxypropyltris(trimethylsiloxy)silane (TRIS) reduced the modulus of such hydrogels, but in many examples the modulus was still higher than may be desired.
U.S. Pat. Nos. 5,358,995 and 5,387,632 describe hydrogels made from various combinations of silicone macromers, TRIS, n-vinyl pyrrolidone (NVP) and DMA. Replacing a substantial portion of the silicone macromer with TRIS reduced the modulus of the resulting hydrogels. Two publications from the same author, "The Role of Bulky Polysiloxanylalkyl Methacrylates in Polyurethane-Polysiloxane Hydrogels", J. Appl. Poly. Sci., Vol. 60, 1193-1199 (1996), and "The Role of Bulky Polysiloxanylalkyl Methacrylates in Oxygen-Permeable Hydrogel Materials", J. Appl. Poly. Sci., Vol. 56, 317-324 (1995) also describe experimental results indicating that the modulus of hydrogels made from reaction mixtures of silicone-macromers and hydrophilic monomers such as DMA decreases with added TRIS.
The use of methacryloxypropylbis(trimethylsiloxy)methylsilane (MBM) to make hard contact lenses was described in WO 9110155 and in JP 61123609.
When relatively high levels of bulky silicone-containing monomers such as TRIS are incorporated into the hydrogels made from silicone-containing macromers and hydrophilic monomers, the elasticity, or the speed at which the polymer returns to its original shape after stress can be reduced to an extent that is unacceptable to the contact lens wearer.
There still remains a need in the art for silicone hydrogels which are soft enough to make soft contact lenses, which possess high oxygen permeability, suitable water content, and sufficient elasticity, and are comfortable to the contact lens wearer.


In an equipment cabinet equipped with a rack for electronic and electrical insertable units, all casing components, including side walls, a rear wall, a door, a top and a bottom, are provided with mating contact faces along the component edges so as to provide a shield against electromagnetic radiation. Contact strips made of an electrically well conducting material are arranged between these contact faces.

The present invention relates to an equipment cabinet for electronic and electrical insertable units that includes a self-supporting rack for holding the insertable units as well as metal casing components including side walls, a rear wall, a door, a top and a bottom.
Equipment cabinets for accommodating electronic components must meet a number of requirements. For example, these cabinets must have excellent mechanical strength--also with respect to vibratory stresses and during earthquakes. The additionally required good accessibility for the inserted units requires easily removable casing components which not only provide protection against dust and water but also against electromagnetic radiation.
In order to realize optimum high frequency shielding, it has been attempted in the past to use the casing to form the most gap-free, closed, electrically conductive casing around the equipment cabinet. This has been done by producing a plurality of conductive connections between the various casing components and the rack and between the rack components themselves as well as between the individual casing components. These procedures required careful, expensive manual labor in the assembly of the equipment cabinet and particularly a very good, electrically conductive, supporting rack as it can be realized by way of electroplating surface refinement, for example with nickel, or by the use of stainless steel. It is not possible to selectively or subsequently provide an HF shield for racks that were manufactured for simple applications in an inexpensive manner and without consideration of shielding measures.
Another solution of the shielding problem is the insertion of the rack in a box that is closed on all sides, is soldered or welded shut and on which rests a door that is provided with contacts; however, the drawback here is the poor accessibility of the inserted components since access is possible only through the opened door.
An equipment cabinet gasket is known which includes a frame-type rack to which the casing components, namely walls, door, top and bottom are fastened. The frame rack is composed of metal profiles that are provided with outwardly projecting flanges or strips onto which sealing strips are clamped. These sealing strips are made of rubber and, for fastening purposes, are provided with a spring-elastic insert that has a U-shaped profile and is provided with barbs. On its exterior, the sealing strip is covered with a conductive braided metal structure that electrically connects the frame rack with the screwed-on casing components. The metal profiles and the sealing strip are of an expensive design, a gap-free HF shield is hardly realizable (unexamined published European Patent Application EP 0,427,550).
Also known is a switch cabinet including a frame rack that is provided with an all-around casing equipped with a door. A box-shaped insert that is closed on all sides and is pushed into the frame rack serves as the HF shield. A shielding plate is inserted into the interior face of the door. For the purpose of sealing, the edges of the insert as well as those of the shielding plate are provided with plug-in, resilient contact strips which, when the door is in the closed position, are congruent with one another. However, the desired high frequency shield is here obtained at high expense in the form of an insert (German Patent 3,611,693 which corresponds to U.S. Pat. No. 4,760,496).
Sealing strips for sealing and shielding slits and crevices in devices to be shielded where the sealing strips are composed of a cord of braided metal and a vulcanized-on rubber sealing profile are disclosed in Unexamined Published German Patent Application DE 2,829,255.


Metals useful in the formation of hydrides for applications such as batteries are advantageously activated by a low temperature low pressure process. This process which is useful at room temperature and atmospheric pressure involves treating the metal such as LaNi.sub.5 with boron reducing agents such as NaBH.sub.4.

1. Field of the Invention
This invention relates to metal hydrides and in particular to processes involving such hydrides.
2. Art Background
Metal hydrides are used in a variety of industrial applications. Although there are many such applications, possibly the most prominent is the use of metal hydrides in batteries. For example, secondary nickel-metal hydride batteries employ lanthanum nickel hydride (or alloy modifications) or other intermetallic hydrides in the negative electrode. A variety of other uses involving energy storage and transfer have been described. Irrespective of the application, a crucial step in preparation is activation of the intermetallic. Activation is achieved, for example, by repeatedly reducing the metal such as LaNi.sub.5 to the corresponding hydride with H.sub.2 gas at high pressure and/or temperature followed by removal of hydrogen at lower pressures.
This cyclic process, generally denominated activation, is believed to serve two purposes. Each reduction to the hydride 1) removes reducible surface oxides which tend to interfere with the functioning of the material in the ultimate desired application, and 2) a reduction in particle size resulting from an increase in volume that causes fracture of the metal particles. Thus, activation, it is believed, removes oxide and produces in the hydride a greater surface area than was present in the corresponding metal. Both the removal of the oxide and the increase in surface area enhances the operation of the material for applications such as batteries where a surface oxide and a low surface area reduce the rate of the hydriding reactions.
Activation of hydrides has typically been performed at relatively high pressures (up to 1000 psi) and temperatures as high as 450.degree. C., by subjecting the metal directly to hydrogen gas. Clearly, although such conditions are not prohibitive to commercial use, they require relatively large expenditures for suitable equipment. Thus, an alternative to high pressure reaction of hydrogen gas with the corresponding metal would be quite desirable.