Coated inflatable fabrics and more particularly concerns airbag cushions to which very low add-on amounts of silicone-based coating have been applied and which exhibit extremely low air permeability are provided. The inventive inflatable fabrics are primarily for use in automotive restraint cushions that require low permeability characteristics (such as side curtain airbags). Traditionally, heavy, and thus expensive, coatings of compounds such as neoprene, silicones, and the like, have been utilized to provide such required low permeability. The inventive fabric utilizes an inexpensive, very thin, substantially uniform silicone coating to provide such necessarily low permeability levels. Thus, the inventive coating comprises at least a single layer comprising a majority of silicone-based material, wherein the total thickness of the single layer is at most about 3.0 ounces per square yard as applied to a target fabric surface. The inventive airbag exhibits a characteristically long leak-down rate as compared to other coated airbags.

This invention relates generally to coated inflatable fabrics and more particularly concerns airbag cushions to which very low add-on amounts of silicone-based coating have been applied and which exhibit extremely low air permeability. The inventive inflatable fabrics are primarily for use in automotive restraint cushions that require low permeability characteristics (such as side curtain airbags). Traditionally, heavy, and thus expensive, coatings of compounds such as neoprene, silicones, and the like, have been utilized to provide such required low permeability. The inventive fabric utilizes an inexpensive, very thin, substantially uniform silicone coating to provide such necessarily low permeability levels. Thus, the inventive coating comprises at least a single layer comprising a majority of silicone-based material, wherein the total thickness of the single layer is at most about 3.0 ounces per square yard as applied to a target fabric surface. The inventive airbag exhibits a characteristically long leak-down rate as compared to other coated airbags.
Airbags for motor vehicles are known and have been used for a substantial period of time. A typical construction material for airbags has been a polyester or nylon fabric, coated with an elastomer such as neoprene, or silicone. The fabric used in such bags is typically a woven fabric formed from synthetic yam by practices that are well known in the art.
The coated material has found acceptance because it acts as an impermeable barrier to the inflation medium. This inflation medium is generally a gas generated from a gas generator or inflator. Such gas is conveyed into the cushion at a relatively warm temperature. The coating obstructs the permeation of the fabric by such hot gas, thereby permitting the cushion to rapidly inflate without undue decompression during a collision event.
Airbags may also be formed from uncoated fabric which has been woven in a manner that creates a product possessing low permeability or from fabric that has undergone treatment such as calendaring to reduce permeability. Fabrics which reduce air permeability by calendaring or other mechanical treatments after weaving are disclosed in U.S. Pat. No. 4,921,735; U.S. Pat. No. 4,977,016; and U.S. Pat. No. 5,073,418 (all incorporated herein by reference).
Traditional silicone coatings have proven ineffective at low add-on coating weights over target airbag fabric surfaces for low permeability characteristics. Typically, such coatings have required extremely thick layers of materials to provide the desired low permeability levels required for long-term rollover protection situations (particularly for side-curtain airbags). In general, past silicone-based coatings have utilized non-solvent- and solvent-based compositions having dry coating weights for such silicones above 3 and approaching lower levels of at least 4 ounces per square yard for both the front and back panels of side curtain airbags. As will be appreciated by one of ordinary skill in this art, high add-on weights substantially increase the cost of the base fabric for the airbag and make packing within small airbag modules very difficult. Furthermore, traditionally utilized silicones exhibit very low tensile strength and elongation at break characteristics that do not withstand high pressure inflation easily without the utilization of very thick coatings. However, silicones provide excellent durability, aging, and processability benefits, which, if provided with extremely low add-on compositions, would translate into highly desirable airbag coatings. Additionally, as noted in greater detail below, the production of integrally woven side curtain airbags has eliminated the possibility of coating on both the front and back sides of individual fabric panels. As such, there is a greater need to accord relatively thin coating layers on solely the outside panels (i.e., front) of such articles. To date, the ability to restrict coatings to low levels of silicone-based materials has been unavailable.
The use of certain polyurethanes as coatings as disclosed in U.S. Pat. No. 5,110,666 to Menzel et al. (herein incorporated by reference) permits low add on weights reported to be in the range of 0.1 to 1 ounces per square yard but the material itself is relatively expensive and is believed to require relatively complex compounding and application procedures due to the nature of the coating materials. Patentees, however, fail to disclose any pertinent elasticity and/or tensile strength characteristics of their particular polyurethane coating materials. Furthermore, there is no discussion pertaining to the importance of the coating ability (and thus correlated low air permeability) at low add-on weights of such polyurethane materials on side curtain airbags only for fabrics which are utilized within driver or passenger side cushions. All airbags must be inflatable extremely quickly; upon sensing a collision, in fact, airbags usually reach peak pressures within 10 to 20 milliseconds. Regular driver side and passenger side air bags are designed to withstand this enormous inflation pressure; however, they also deflate very quickly in order to effectively absorb the energy from the vehicle occupant hitting the bag. Such driver and passenger side cushions (airbags) are thus made from low permeability fabric, but they also deflate quickly at connecting seams (which are not coated to prevent air leakage) or through vent holes. Furthermore, the low add-on coatings taught within Menzel, and within U.S. Pat. No. 5,945,186 to Li et al., would not provide long-term gas retention; they would actually not withstand the prolonged and continuous pressures supplied by activated inflators for more than about 2 seconds, at the most. The low permeability of these airbag fabrics thus aid in providing a small degree of sustained gas retention within driver and passenger airbag cushions to provide the deflating cushioning effects necessary for sufficient collision protection. Such airbag fabrics would not function well as side curtain airbags, since, at the very least, the connecting seams which create the pillowed, cushioned structures within such airbags, as discussed in greater detail below, would not be coated. As these areas provide the greatest degree of leakage during and after inflation, the aforementioned patented low-coating low-permeability airbag fabrics would not be properly utilized within side curtain airbags. Lastly, polyurethanes suffer from aging and durability problems which requires complexities of mixing and application to overcome such difficulties.
As alluded to above, there are three primary types of different airbags, each for different end uses. For example, driver-side airbags are generally mounted within steering columns and exhibit relatively high air permeabilities in order to act more as a cushion for the driver upon impact. Passenger-side airbags also comprise relatively high air permeability fabrics which permit release of gas either therethrough or through vents integrated therein. Both of these types of airbags are designed to protect persons in sudden collisions and generally burst out of packing modules from either a steering column or dashboard (and thus have multiple xe2x80x9csidesxe2x80x9d). Side curtain airbags, however, have been designed primarily to protect passengers during rollover crashes by retaining its inflation state for a long duration (for example, exhibiting a retention of at least 50% of the initial pressure after 5 seconds subsequent to high pressure inflation) and generally unroll from packing containers stored within the roofline along the side windows of an automobile (and thus have a back and front side only). Side curtain airbags therefore not only provide cushioning effects but also provide protection from broken glass and other debris. As such, it is imperative that side curtain airbags, as noted above, retain large amounts of gas, as well as high gas pressures, to remain inflated throughout the longer time periods of the entire potential rollover situation. To accomplish this, these side curtains are generally coated with very large amounts of silicone sealing materials on both the front and back sides. Since most side curtain airbag fabrics comprise woven blanks that are sewn, sealed, or integrally woven together, discrete areas of potentially high leakage of gas are prevalent, particularly at and around the seams. It has been accepted as a requirement that heavy coatings were necessary to provide the low permeability (and thus longer leak-down time) necessary for side curtain airbags. Without such heavy coatings, such airbags would most likely deflate too quickly and thus would not function properly during a rollover collision. As will be well understood by one of ordinary skill in this art, such heavy coatings add great cost to the overall manufacture of the target side curtain airbags. There is thus a great need to manufacture low permeability side curtain airbags with less expensive (preferably lower coating add-on weight) coatings without losing the aging, humidity, and permeability characteristics necessary for proper functioning upon deployment. To date, there has been little accomplished, if anything at all, alleviating the need for such thick and heavy airbag coatings from side curtain airbags. Furthermore, since silicones (i.e., polyorganosiloxanes and the like) provide the best overall aging stability and durability performance as airbag coatings, there is a desire to utilize such beneficial types of materials for low permeability airbags. Unfortunately, to date the only teachings regarding such silicone-based materials concern extremely thick, and thus costly and difficult to handle and apply, coating formulations. A need thus exists to provide lower add-on weights for silicone-based airbag coating compositions, but with the same aging, durability, and low permeability performance characteristics.
Furthermore, there is a current drive to store such low permeability side curtain airbags within cylindrically shaped modules. Since these airbags are generally stored within the rooflines of automobiles, and the area available is quite limited, there is always a great need to restrict the packing volume of such restraint cushions to their absolute minimum. However, the previously practiced low permeability side curtain airbags have proven to be very cumbersome to store in such cylindrically shaped containers at the target automobile""s roofline. The actual time and energy required to roll such heavily coated low permeability articles as well as the packing volume itself, has been very difficult to reduce. Furthermore, with such heavy coatings utilized, the problems of blocking (i.e., adhering together of the different coated portions of the cushion) are amplified when such articles are so closely packed together. The chances of delayed unrolling during inflation are raised when the potential for blocking is present. Thus, a very closely packed, low packing volume, low blocking low permeability side curtain airbag is highly desirable. Unfortunately, the prior art has again not accorded such an advancement to the airbag industry.
In light of the background above, it can be readily seen that there exists a need for a low permeability, side curtain airbag that utilizes lower, and thus less expensive, amounts of durable, silicone-based coatings exhibiting good aging characteristics, and therefore exhibit a substantially reduced packing volume over the standard low permeability type side curtain airbags. Such a coated low permeability airbag must provide a necessarily high leak-down time upon inflation and after long-term storage. Such a novel airbag and a novel coating formulation provides marked improvements over the more expensive, much higher add-on airbag coatings (and resultant airbag articles) utilized in the past.
It is therefore an object of this invention to provide a coated airbag, wherein the coating comprises a majority (at least) of silicone materials, is present in a very low add-on weight, and possesses extremely high leak-down time characteristics after inflation and thus complementary low permeability characteristics. Another object of the invention is to provide an inexpensive side curtain airbag cushion. A further object of this invention is to provide an highly effective airbag coating formulation which may be applied in very low add-on amounts to obtain extremely low permeability airbag structures after inflation. An additional object of this invention is to provide an airbag coating formulation which not only provides beneficial and long-term low permeability, but also exhibits excellent long-term storage stability (through heat aging and humidity aging testing).
Accordingly, this invention is directed to an airbag cushion comprising a coated fabric, wherein said fabric is coated with an elastomeric composition in an amount of at most about 3.0 ounces per square yard, preferably, at most about 2.5 ounces per square yard of the fabric; wherein said elastomeric composition comprises at least 50% by weight of the entire composition of silicone-based materials; and wherein said airbag cushion, after long-term storage, exhibits a characteristic leak-down rate of at least half of its initial inflation pressure (and thus upon retention of at least half of the inflation gas itself) of at least 5 seconds, preferably higher than 10, and most preferably higher than 50. Also, this invention concerns an airbag cushion comprising a coated fabric, wherein said fabric is coated with an elastomeric composition comprising at least 50% by weight of the entire composition of solvent-based silicone materials comprising from 10 to 90% solids content; and wherein said airbag cushion, after long-term storage, exhibits a characteristic leak-down rate of at least half of its initial inflation pressure (and thus upon retention of at least half of the inflation gas itself) of at least 5 seconds.
The term xe2x80x9ccharacteristic leak-down ratexe2x80x9d is intended to encompass the measurement of time required for the pressure within a target coated airbag to be reduced from an inflation pressure to half of its initial inflation pressure, for example from about 30 psi to 15 psi, or from about 15 to about 7 psi, due to escape of inflation gas through openings within the airbag and within the coating which develop upon exposure to such high pressures. Thus, this measurement begins the instant after peak initial pressure is reached upon inflation (such as, traditionally, about 30 psi, or as low as 7 psi) with a standard inflation module which continues to pump gas into the target airbag during and after peak initial pressure is reached. It is well understood that the pressure of gas forced into the airbag after peak initial pressure is reached will not remain stable (it decreases during the subsequent introduction of inflation gas), and that the target airbag will inevitably permit escape of a certain amount of inflation gas during that time. The primary focus of such side curtain airbags (as noted above) is to remain inflated for as long as possible in order to provide sufficient cushioning protection to vehicle occupants during rollover accidents. The greater amount of gas retained, the better cushioning effects are provided the passengers. Thus, the longer the airbag retains a large amount of inflation gas, and consequently the greater the characteristic leak-down time, the better cushioning results are achieved. At the very least, the inventive airbag must retain at least half of its inflated gas volume 7 seconds subsequent to reaching peak initial pressure.
In an alternative, such a term is also intended to encompass the measurement of time required for the entire amount of inflation gas introduced within an already-inflated (to a peak initial pressure which xe2x80x9copensxe2x80x9d up the areas of weak sealing) and deflated airbag cushion upon subsequent re-inflation at a constant pressure at 10 psi. It is well known and well understood within the airbag art, and particularly concerning side curtain (low permeability) airbag cushions, that retention of inflation gas for long periods of time is of utmost importance during a collision. Side curtain airbags are designed to inflate as quickly as driver- and passenger-side bags, but they must deflate very slowly to protect the occupants during roll over and side impact. Thus, it is imperative that the bag exhibit a very low leakage rate after the bag experiences peak pressure during the instantaneous, quick inflation. Hence, the coating on the bag must be strong enough to withstand the shock and stresses when the bag is inflated so quickly. Thus, a high characteristic leak-down time measurement is paramount in order to retain the maximum amount of beneficial cushioning gas within the inflated airbag. Airbag leakage after inflation (and after peak pressure is reached) is therefore closely related to actual pressure retention characteristics. The pressure retention characteristics (hereinafter referred to as xe2x80x9cleak-down timexe2x80x9d) of already-inflated and deflated side curtain airbags can be described by a characteristic leak-down time t, wherein:       t              xe2x80x83                  (      second      )        =                    Bag                          xe2x80x83                        volume                          xe2x80x83                                  (                      ft            3                    )                                                  Volumetric                                      xe2x80x83                                    leakage                                      xe2x80x83                                    rate                                      xe2x80x83                                                  (              SCFM                                          *)                                  xe2x80x83                        at                          xe2x80x83                        10                          xe2x80x83                        Psi              xc3x97    60
        *          SCFM      :              xe2x80x83                          standard                          xe2x80x83                        cubic                          xe2x80x83                        feet                          xe2x80x83                        per                          xe2x80x83                                  minute          .
It is understood that the 10 psi constant is not a limitation to the invention; but merely the constant pressure at which certain leak-down time measurements can be made. Thus, even if the pressure is above or below this amount during actual inflation or after initial pressurizing of the airbag, the only limitation is that if one of ordinary skill in the art were to measure the bag volume and divide that by the volumetric leakage rate time (measured by the amount leaking out of the target airbag during steady state inflation at 10 psi), the resultant measurement in time would be at least 10 seconds at a coating add-on weight of about 1.5 ounces per square yard. Preferably, this time is greater than about 10 seconds; more preferably, greater than about 20 seconds; still more preferably in excess of about 40 seconds; and most preferably, greater than about 50 seconds.
Likewise, the term, xe2x80x9cafter long-term storagexe2x80x9d encompasses either the actual storage of an inventive airbag cushion within an inflator assembly (module) within an automobile, and/or in a storage facility awaiting installation. Such a measurement is generally accepted, and is well understood and appreciated by the ordinarily skilled artisan, to be made through comparable analysis after representative heat and humidity aging tests. These tests generally involve 120xc2x0 C. oven aging for 14 days, or, alternatively, but comparably, oven aging at 80xc2x0 C. and 95% relative humidity aging for 14 days. Such tests are universally accepted as proper estimations of the conditions of long-term storage for airbag cushions. Thus, this term encompasses such measurement tests. The inventive airbag fabrics must exhibit proper characteristic leak-down times after undergoing such rigorous pseudo-storage testing.
The inventive coating composition must comprise at least 50% by weight of at least one silicone-based elastomer and such a composition may only be present on the target airbag surface in an amount of at most 3.0 ounces per square yard of fabric. Preferably, this amount ranges from about 0.5 to about 2.5 ounces per square more preferably from about 1.0 to about 2.0; and most preferably from about 1.5 to about 2.0. Furthermore, the silicone-based elastomer preferably comprises at least 60% by weight of the entire composition, more preferably at least about 75%, yet more preferably at least 90%, and most preferably, at least 95 up to 100%.
The term silicone-based materials or elastomers is intended to encompass any compound comprising silicone bonded with at least one oxygen atom (such as, for example, polyorganosiloxanes). Preferred compounds of this type are listed below.
It is this high amount of silicone-based materials with a correspondingly low add-on weight and resultant high leak-down time (provided for the target airbag fabric) which is of greatest importance and which is so highly unexpected within this invention. As noted above, the utilization of silicone-based materials has been of great desire within low-permeability airbag articles; however, due to low elongation and tensile strength characteristics, the coatings required to provide the desired low permeability measurements were too thick (and too expensive) to provide a viable coating within the industry. The ability to provide silicone-based coatings with substantially uniform coating thicknesses (with extremely low thickness variations) has created the opportunity now to utilize the desired silicones as the prominent coating materials within these specific low-permeability applications.
Thus, the silicones within the inventive coatings are preferably solvent-based and exhibit a solids content of between about 10 and 90% of the total silicone composition. Preferably, this amount is from about 20 to about 80%; more preferably from about 30 to about 75%; and most preferably from about 35 to about 65%. The solids content permits greater control of application on the target fabric surface. Generally, a dry coating is ineffective and an overly liquid composition (although easier to handle on an industrial scale initially) effectively prevents a low variation (in terms of thickness) coating to be applied over the target fabric surface. It has now been found that silicone-based materials will provide the desired high elongation at break and tensile strength characteristics if the coating applied to the target fabric surface does indeed exhibit a substantially uniform thickness. Since the coating must fill the interstitial spaces between yams and seams, the more uneven the coating in such discrete areas, the easier it is to displace it. A more balanced, and thus stronger, coating, thus provides the needed ability to retain the greatest amount of coating over its applied area during an inflation event for the longest amount of time. Thus, the specific silicone-based coating composition herein dicussed must be in contact with the target fabric surface. It may be treated with other materials to aid in blocking reduction (i.e., adhesion between folded portions of coated fabric), greater aging stability, and moisture resistance, if desired.
In the past, knife coating (including knife-over-gap) was the primary method of applying silicone-based materials to airbag surfaces. However, due to the physical state of such traditional materials (i.e., low solids content), the applied coating was extremely difficult to apply in a uniform fashion (with respect to coating thickness). It has now been found that the utilization of the higher solids content silicone-based materials noted above, the application method may be followed with, for example, a wider gap during the knife coating, permitting greater control (and less xe2x80x9csmearingxe2x80x9d) of the applied coating to effectuate the desired substantially uniform, low add-on, level.
Hence, with a substantially uniform, low add-on thickness, the silicone-based coating exhibits the desired high levels of tensile strength of at least 1,000 psi (preferably, at least 1,100, more preferably at least 1,200, and most preferably at least 1,250) and an elongation to break of greater than about 200% (preferably in excess of about 300%, more preferably greater than 500%, and most preferably greater than about 600%). These characteristics of the elastomer translate to a coating that is both very strong (and thus will withstand enormous pressures both at inflation and during the time after inflation and will not easily break) and can stretch to compensate for such large inflation, etc., pressures. Thus, when applied at the seams of a side curtain airbag, as well as over the rest of the airbag structure, the coating will most preferably (though not necessarily) form a continuous film. This coating acts to both fill the individual holes between the woven yarns and/or stitches, etc., as well as to xe2x80x9ccementxe2x80x9d the individual yams in place. During inflation, then, the coating prevents leakage through the interstitial spaces between the yams and aids in preventing yam shifting (which may create larger spaces for possible gas escape).
Synergistically, the availability of such high tensile strength and high elongation at break silicone-based materials permits the consequent utilization, surprisingly, of extremely low add-on weight amounts of such highly desirable coating formulations (as noted previously). Normally, the required coatings on side curtain airbags are very high, at least 3.0 ounces per square yard (with the standard actually much higher than that, at about 4.0). The inventive airbag cushions require much less coating amounts (in terms of add-on weights on the target fabric) to achieve the desired leak down rate. The inventive coatings are present preferably in an amount of about at most 3.0 (preferably less, such as 2.0, more preferably 1.8, still more preferably, about 1.5, and most preferably, as low as 0.8) ounces per square yard to effectuate the desired high leak-down (low permeability). Furthermore, such silicone-based coatings exhibit excellent heat and humidity aging stability. Thus, the coating compositions and coated airbags are clearly improvements within this specific airbag art.
Examples of silicone-based materials and/or elastomers acceptable for utilization within this invention by exhibiting the proper ability to form a substantially uniformly thick permeability controlling coating on a target airbag fabric surface include such beneficial solids content compositions as RHODIA(copyright) HS-60, available from Rhodia, Inc. and possessing a solids content of about 50%, and Dow-Coming TR-55 silicones exhibiting solids content measurements of about 30%, both in relation to the total solvent-based compositions. The solvents present within the potential high solids content compositions may be any standard organic liquid solvents, such as lower alcohols (isopropanol, ethanol, butanol, and the like), aromatic liquids, such as toluene, aniline, and the like, methyl ethyl ketone, and any other such standard solvents.
Other possible components present within the elastomer coating composition are viscosity modifying agents, antioxidants, flame retardants, coalescent agents, adhesion promoters, and colorants.
Primer adhesives may be utilized to facilitate adhesion between the surface of the target fabric and the elastomer itself. Thus, although it is preferable for the elastomer to be the sole component of the entire elastomer composition in contact with the fabric surface, it is possible to utilize adhesion promoters, such as isocyanates, epoxies, functional silanes, and other such resins with adhesive properties, without deleteriously effecting the ability of the elastomer to provide the desired low permeability for the target airbag cushion. An overtreatment component, as noted above, may also be utilized to effectuate proper non-blocking characteristics to the target airbag cushion. Such a treatment may perform various functions, including, but not limited to, improving aging of the elastomer (such as with silicone) or providing blocking resistance due to the adhesive nature of the coating materials.
Airbag fabrics must pass certain tests in order to be utilized within restraint systems. One such test is called a blocking test which indicates the force required to separate two portions of coated fabric from one another after prolonged storage in contact with each other (such as an airbag is stored). Laboratory analysis for blocking entails pressing together coated sides of two 2 inch by 2 inch swatches of airbag fabric at 5 psi at 100xc2x0 C. for 7 days. If the force required to pull the two swatches apart after this time is greater than 50 grams, or the time required to separate the fabrics utilizing a 50 gram weight suspended from the bottom fabric layer is greater than 10 seconds, the coating fails the blocking test. Clearly, the lower the required separating shear force, the more favorable the coating. For improved blocking resistance (and thus the reduced chance of improper adhesion between the packed fabric portions), topcoat components may be utilized, such as talc, silica, silicate clays, and starch powders, as long as the add-on weight of the entire elastomer composition (including the topcoat) does not exceed about 3.0 ounces per square yard, preferably about 3.0 ounces per square yard (and preferably exists at a much lower level, about 2.0, for instance). Preferably, talc is the utilized topcoat (if one is present at all). Other potential topcoats (though much less desired) include, polyamides, NBR rubbers, EPDM rubbers, and the like, as long as the elastomer composition (including the topcoat) does not exceed the 3.0 ounces per square yard of the add-on weight to the target fabric.
Two other tests which the specific coated airbag cushion must pass are the oven (heat) aging and humidity aging tests. Such tests also simulate the storage of an airbag fabric over a long period of time upon exposure at high temperatures and at relatively high humidities. These tests are actually used to analyze alterations of various different fabric properties after such a prolonged storage in a hot ventilated oven ( greater than 100xc2x0 C.) (with or without humid conditions) for 2 or more weeks. For the purposes of this invention, this test was used basically to analyze the air permeability of the coated side curtain airbag by measuring the characteristic leak-down time (as discussed above, in detail). The initially produced and stored inventive airbag cushion should exhibit a characteristic leak-down rate of half of its initial inflation pressure of at least 5 seconds, and preferably much higher. Alternatively, a characteristic leak-down time of greater than about 5 seconds (upon re-inflation at 10 psi gas pressure after the bag had previously been inflated to a peak pressure above about 15 psi and allowed to fully deflate) under such harsh storage conditions. Other additives may be present within the elastomer composition, including, and not limited to, UV stabilizers, fillers, pigments, and crosslinking/curing agents, as are well known within this art.
The substrate to which the inventive high solids content silicone-based elastomeric coatings are applied to form the airbag base fabric in accordance with the present invention is preferably a woven fabric formed from yarns comprising synthetic fibers, such as polyamides or polyesters. Such yam preferably has a linear density of about 105 denier to about 840 denier, more preferably from about 210 to about 630 denier, and most preferably from about 315 to about 420 denier. Such yarns are preferably formed from multiple filaments wherein the filaments have linear densities of about 6 denier per filaments or less and most preferably about 4 denier per filament or less. In the more preferred embodiment such substrate fabric will be formed from fibers of nylon, and most preferred is nylon 6,6. It has been found that such polyamide materials exhibit particularly good adhesion and maintenance of resistance to hydrolysis when used in combination with the coating according to the present invention. Such substrate fabrics are preferably woven using fluid jet weaving machines as disclosed in U.S. Pat. Nos. 5,503,197 and 5,421,378 to Bower et al. (incorporated herein by reference). Such woven fabric will be hereinafter referred to as an airbag base fabric. As noted above, the inventive airbag must exhibit extremely low permeability and thus must be what is termed a xe2x80x9cside curtainxe2x80x9d airbag. As noted previously and extensively, such side curtain airbags (a.k.a., cushions) must retain a large amount of inflation gas during a collision in order to accord proper long-duration cushioning protection to passengers during rollover accidents. Any standard side curtain airbag may be utilized in combination with the low add-on coating to provide a product which exhibits the desired leak-down times as noted above. Most side curtain airbags are produced through labor-intensive sewing or stitching (or other manner) together two separate woven fabric blanks to form an inflatable structure. Furthermore, as is well understood by the ordinarily skilled artisan, such sewing, etc., is performed in strategic locations to form seams (connection points between fabric layers) which in turn produce discrete open areas into which inflation gasses may flow during inflation. Such open areas thus produce pillowed structures within the final inflated airbag cushion to provide more surface area during a collision, as well as provide strength to the bag itself in order to withstand the very high initial inflation pressures (and thus not explode during such an inflation event). Other side curtain airbag cushions exist which are of the one-piece woven variety. Basically, some inflatable airbags are produced through the simultaneous weaving of two separate layers of fabric which are joined together at certain strategic locations (again, to form the desired pillowed structures). Such cushions thus present seams of connection between the two layers. It is the presence of so many seams (in both multiple-piece and one-piece woven bags) which create the aforementioned problems of gas loss during and after inflation. The possibility of yam shifting, particularly where the yarns shift in and at many different ways and amounts, thus creates the quick deflation of the bag through quick escaping of inflation gasses. Thus, the base airbag fabrics do not provide much help in reducing permeability (and correlated leak-down times, particularly at relatively high pressures). It is this seam problem which has primarily created the need for the utilization of very thick, and thus expensive, coatings to provide necessarily low permeability in the past.
Recently, a move has been made away from both the multiple-piece side curtain airbags (which require great amounts of labor-intensive sewing to attached woven fabric blanks) and the traditionally produced one-piece woven cushions, to more specific one-piece woven fabrics which exhibit substantially reduced floats between woven yarns to substantially reduce the unbalanced shifting of yarns upon inflation, such as in Ser. No. 09/406,264, to Sollars, Jr., now U.S. Pat. No. 6,220,309, the specification of which is completely incorporated herein. These one-piece woven bags are generally produced on dobby or jacquard fluid-jet looms, preferably the utilized one-piece airbag is made from a jacquard weaving process. With such an improvement, the possibility of high leakage at the seams is substantially reduced. These airbags provide balanced weave constructions at and around attachment points between two layers of fabrics such that the ability of the yams to become displaced upon inflation at high pressures is reduced as compared with the standard one-piece woven airbags (basically, the floats within the woven seams forming the inflation chambers of such cushions number at most 3 picks in order to provide such desired low permeability characteristics). Unfortunately, such inventive one-piece woven bags are still problematic in that the weave intersections may be displaced upon high pressure inflation such that leakage will still most likely occur at too high a rate for proper functioning. As a result, there is still a need to coat such one-piece woven structures with materials which reduce and/or eliminate such an effect. However, such one-piece woven structures permit extremely low add-on amounts of elastomeric coatings for low permeability effects. In fact, these inventive airbags function extremely well with low add-on coatings below 2.0 and as low as about 1.0 ounces per square yard.
Furthermore, although it is not preferred in this invention, it has been found that the inventive coating composition provides similar low permeability benefits to standard one-piece woven airbags, particularly with the inventive low add-on amounts of high tensile strength, high elongation, silicone-based elastomer materials; however, the amount of coating required to permit high leak-down times is much higher than for the aforementioned Sollars, Jr. inventive one-piece woven structure. Thus, add-on amounts of as much as 1.5 and even up to about 2.5 ounces per square yard may be necessary to effectuate the desired low level of air permeability for these other one-piece woven airbags. Even with such higher add-on coatings, the inventive coatings themselves clearly provide a marked improvement over the standard, commercial, prior art silicone, etc., coatings (which must be present in amounts in excess of 3.0 ounces per square yard).
Additionally, it has also been found that the inventive coating compositions, at the inventive add-on amounts, etc., provide the same types of benefits with the aforementioned sewn, stitched, etc., side curtain airbags. Although such structures are highly undesirable due to the high potential for leakage at these attachment seams, it has been found that the inventive coating provides a substantial reduction in permeability with correlative lower add-on amounts than with standard low permeability, high add-on silicone and neoprene rubber coating formulations. Such add-on amounts for the inventive coatings will approach the 3.0 ounces per square yard, but lower amounts have proven effective (lower than 2.5, lower than 2.0, and most preferably less than about 1.5 ounces per square yard, for example) depending on the utilization of a sufficiently high tensile strength and sufficiently stretchable elastomeric component within the coating composition directly in contact with the target fabric surface. Again, with the ability to reduce the amount of coating materials (which are generally always quite expensive), while simultaneously providing a substantial reduction in permeability to the target airbag structure, as well as high resistance to humidity and extremely effective aging stability, the inventive coating composition, and the inventive coated airbag itself is clearly a vast improvement over the prior airbag coating art.
Of particular importance within this invention is the ability to pack the coated airbag cushions within cylindrical storage containers at the roof line of a target automobile in as small a volume as possible. In a rolled configuration (in order to best fit within the cylindrical container itself, and thus in order to best inflate upon a collision event downward to accord the passengers sufficient protection), the inventive airbag may be constricted to a cylindrical shape having a diameter of at most 23 millimeters. In such an instance, with a 2 meter long cylindrical roofline storage container, the necessary volume of such a container would equal about 830 cm3.(with the volume calculated as 2[Pi]radius2) Standard rolled packing diameters are at least 25 millimeters for commercially available side curtain airbag cushions (due to the thickness of the required coating to provide low permeability characteristics). Thus, the required cylindrical container volume would be at least 980 cm3. Preferably, the rolled diameter of the inventive airbag cushion during storage is at most 20 millimeters (giving a packed volume of about 628 cm3) which is clearly well below the standard packing volume. In relation, then, to the depth of the airbag cushion upon inflation (i.e., the length the airbag extends from the roofline down to its lowest point along the side of the target automobile, such as at the windows), the quotient of the inventive airbag cushion""s depth (which is standard at approximately 17 inches or 431.8 millimeters) to its rolled packed diameter should be at least about 18.8. Preferably this quotient should be about 21.6 (20 millimeter diameter), and, at its maximum, should be about 24 (with a minimum diameter of about 18 millimeters). Of course, this range of quotients does not require the depth to be at a standard of 17 inches, and is primarily a function of coating thickness, and thus add-on weight.
The inventive coatings are preferably knife-over-gap coated across the fabric substrate and dried and cured to form the necessarily thin, substantially uniform coating. Other controlled thickness coating methods can be utilized, including, without limitation, floating knife, and knife-over-foam pad methods, to name a few different method types. Particularly preferred, however, is fixed-gap knife coating in order to provide a uniform coating (or possibly film) on the target fabric surface. A fixed-gap coating procedure which permits even coating over the raised yarns of the target fabric is highly desired. The final dry weight of the coating is preferably from about 0.5-3.0, more preferably from 1.0-2.5 ounces per square yard or less and most preferably 1.5-2.25 ounces per square yard or less. The resultant airbag cushion is substantially impermeable to air when measured according to ASTM Test D737, xe2x80x9cAir Permeability of Textile Fabrics,xe2x80x9d standards.
While the invention will be described and disclosed in connection with certain preferred embodiments and practices, it is in no way intended to limit the invention to those specific embodiments, rather it is intended to cover equivalent structures structural equivalents and all alternative embodiments and modifications as may be defined by the scope of the appended claims and equivalence thereto.
In order to further describe the present invention the following nonlimiting examples are set forth. These examples are provided for the sole purpose of illustrating some preferred embodiments of the invention and are not to be construed as limiting the scope of the invention in any manner.
Some other silicone-based elastomers potentially preferred within this invention include:
Specific compounding and application to target fabric of the inventive silicone-based materials was undertaken as follows:
The following coating formulation was first compounded:
This formulation was prepared and applied to a one-piece woven side-curtain airbag made from 420 denier nylon 6,6 yarns and including woven-in seams exhibiting no more than 3 sequential floats per pick (in accordance with the preferred bag within U.S. patent application No. 09/406,264, to Sollars, Jr., now U.S. Pat. No. 6,220,309).
The solvent dispersion was applied to the bag with a knife over roll coating method. The coating gap of 825 microns was used in order to target a coating add-on of 2.0 oz/yd. The solvent was removed in the drying oven and the fabric cured 180(copyright)C for 2 minutes followed by a post cure of 7 minutes in a separate oven to ensure optimum cure. The actual coating add-on was determined to be 1.78 oz/yd2.
The test bag was then tested on a high pressure permeability tester by incrementally increasing the pressure up to a maximum of 15 psi. The flow rates observed were as follows:
After reaching 15 psi, the air supply valve was closed and the amount of time to drop from the peak pressure of 15 psi to a pressure of 7 psi was determined to be 33 seconds.
The same coating formulation in EXAMPLE 1, above, was applied to three separate one-piece woven airbags (as above), but in different fabric add-on weights. EXAMPLE 2 was applied in an amount of about 2.25 ounces per square yard; EXAMPLE 3, about 1.90; and EXAMPLE 4 about 1.56. The results for each (leak-down rate) is tabulated below with a final notation showing the actual time required for the inventive airbags to lose inflation pressure to about half of its initial level.
Thus, the inventive low add-on silicone-based coatings provided excellent long-term low permeability to the target airbags.

Low permeability airbag cushions having extremely low silicone-based coating levels


A probe wafer electrically connected to a semiconductor wafer on which a plurality of semiconductor chips are formed includes: a wafer substrate for pitch conversion including a wafer connection surface and an apparatus connection surface opposing the wafer connection surface; a plurality of wafer connection terminals formed on the wafer connection surface of the wafer substrate for pitch conversion, at least one wafer connection terminal provided for each of the semiconductor chips and electrically connected to an input/output terminal of the corresponding semiconductor chip; a plurality of apparatus connection terminals formed on the apparatus connection surface of the wafer substrate in one-to-one relation with the plurality of wafer connection terminals at an interval different from an interval of the wafer connection terminals, to be electrically connected to an external apparatus; and a plurality of transfer paths, each electrically connecting a corresponding wafer connection terminal to an apparatus connection terminal.

1. Technical Field
The present invention relates to a probe wafer, a probe apparatus, and a test system.
2. Related Art
In a test of a semiconductor chip, an apparatus for testing acceptability of each of semiconductor chips in the state that they are formed on a semiconductor wafer is known (e.g., by Patent Document No. 1). Such an apparatus may be equipped with a probe card that can be collectively electrically connected to a plurality of semiconductor chips.
The probe card is provided between a test substrate of a test apparatus and a semiconductor wafer. Here, when the interval between the terminals of the test substrate is different from the interval between the terminals of the semiconductor wafer, the probe card should have a certain mechanism for absorbing the difference. One exemplary mechanism is to cause the interval between terminals on the front surface of the probe card to differ from the interval between terminals on the rear surface. By adopting such a mechanism, the terminals on the front surface can be connected to the corresponding terminals on the rear surface in the probe card. Patent Document No. 1: Japanese Patent Application Publication No. 2002-222839
Patent Document No. 2: WO 2003/062837
A general probe card is formed using a print substrate or the like (e.g., see Patent Document No. 2). By forming a plurality of probe pins on the print substrate, the probe card can be collectively electrically connected to a plurality of semiconductor chips.
However, a semiconductor wafer has a different thermal expansion coefficient than that of a print substrate. Therefore, when the temperature fluctuates in such occasions as when the heat is generated by semiconductor chips during a test, and in a heat test or in a cooling test of the semiconductor chips, there sometimes happens that the electrically connection between the semiconductor chip and the probe card is removed. Such a problem will be more noticeable when a test involves semiconductor chips formed on a semiconductor wafer having a large area.

Probe wafer, probe device, and testing system


A new pacemaker apparatus for treating the physiological electric conduction of the heart that includes a conduction abnormality in a ventricle. The pacemaker includes a pulse generator and a pacing electrode located in the heart, the pulse generator providing pacing signals to the pacing electrode. The pacemaker further includes a signal generation circuit that generates electrical signals from heart-related feedback signals that indicate that the pacing electrode is delivering the pacing signals in a region at or near the His bundle of the heart. The combination of the pulse generator and the signal generation circuit indicates that the pacing electrode is delivering the pacing signals in the region, at or near the His bundle of the heart, to electrically bypass the conduction abnormality of the heart in the ventricle.

The present invention relates to a new pacemaker which reestablishes or keeps the physiological electric synchrony of the heart and a method of application in the right ventricular septum, being possible to use, in order to facilitate the implantation and to avoid the connection and disconnection, a sheath to check a proper place and then screw the catheter in said place.
This method together with the pacemaker are responsible for the reestablishment and preservation of the physiological electric synchrony of the heart and is herein referred to as "EB (Electric Bypass)" due to the obtention of an alternative electric circuit and to the creation of the virtual electrode.
With the pacemaker of my invention and its method of application, a septal ventricular stimulation system with a high performance electrical and contractile synchrony is produced, thus significantly changing the implantation of a definitive pacemaker, making them more physiological. In the examples where my invention was applied, several patients with QRS narrowing were tested as well as those suffering disorders in the AV atrio-ventricular and intraventricular impulse conduction. The results show the QRS narrowing phenomena and the orientation of the depolarization with similar vectors compared to those of a depolarization by the His-Purkinje system.
A pacemaker is an electronic apparatus that produces electric impulses, intended to stimulate the cardiac muscle. The number of impulses produced per minute is called frequency. The mechanism is fed from electric power from batteries. These electric impulses are conducted to the heart by means of a cable (or electrode), so that the pacemaker itself (or pulse generator) is placed at a quite shallow surface underneath the skin, while the electrode is placed much more deeply inside the organism, up to the heart.
The first pacemakers, asynchronous, were only blind instruments that continuously produced 70 electric impulses per minute, carrying them up to the heart by means of an electrode. The electronic circuit consisted of a few diodes, transistors, resistors and a capacitor. One or more batteries provided the necessary power to feed the circuit and stimulate the heart. These pacemakers complied very well with their role when the patient's own rhythm was absolutely absent. However when the failure in the rhythm was just intermittent, the pacemaker slightly interfered with the normal rhythm, at the moments when it was reestablished.
Afterwards, the more intelligent pacemakers came out, Pacemakers on demand, that stopped functioning when the cardiac rhythm was reestablished. This supposed the introduction of new circuits, capable of detecting the electronic activity of the heart and new pacemakers were called "on demand" since they just started working when they were necessary.
Pacemakers on demand may be implanted in the atrium, in order to treat failures in the sinus node; or in the ventricle so as to treat the heart block.
An important advancement in the development of programmable pacemakers was to make them more versatile. The first ones only worked under a frequency set in factory, with fixed pulse energy and were able to detect certain level of cardiac electric activity also fixed.
It may be interesting to be able to change the stimulation frequency at certain moments, adjusting it to the organic needs. In other cases, a decrease in the pulse energy may be advantageous to save power and extend the duration of the pacemaker, or on the contrary, increase it if the muscle became resistant. In some patients, it would be useful to get the pacemaker to have higher o lower capacity for detecting electric impulses, in order to eliminate the influence of abnormal rhythms, or external interferences. All of the above-mentioned options became possible with the introduction of the Programmable Pacemaker.
Currently, different kinds of these pacemakers are available, which allow the adjustment of their function to different states of healthy or sick organism without causing any discomfort to the patient.
Programmable pacemakers are insensitive to the needs of the organism and their functioning is to be changed from the outside, so that their adaptability is relative. There are other kinds of pacemakers which are more physiological, that is to say, more capable of meeting the organic needs at every moment, with its continues fluctuation. In cases where the formation of the cardiac stimulus in the atria is maintained, and the problem lies on the conduction block between the atria and the ventricles, a kind of pacemaker which senses atrial activity and then stimulates the ventricles can be introduced. These are the "atrial triggered" pacemakers, which constitute a practical reality, once the problems of implanting two catheters, one in the auricle and the other in the ventricle, are solved. In these pacemakers, as the variations in the atrial rhythm depend on organic needs variations, the pacemaker is led by the body needs
Currently, for cases where it is not possible to use atrial guidance, pacemakers have been developed that are capable of sensing other parameters in the body activity, changing automatically their frequency (self-programming frequency pacemakers). Some pacemakers catch vibrations of the body during movement; others detect breathing activity and accelerate frequency of the heart in combination with the frequency of breathing; others detect fine vibrations in the cardiac electric activity caused by exercise and others being at the stage of design or project respond to the exhaustion of oxygen in blood, to changes in body temperature, or even to many of these causes.
First pacemakers were big and short-lasting. They weighted one hundred grams, had a diameter of 7-8 cm, and 2-3 cm of thickness, wrapped with silicone rubber toughly applied. They were fed by mercury-zinc batteries that could last no more than 2-3 years. Electrodes broke frequently because of the phenomenon called "fatigue of materials".
Nowadays, size has been reduced by a quarter or a fifth, weight has been reduced to less than a third, duration reaches 5-10 years according to the designs, and electrodes are made of a certain design and material that practically prevent their breaking and allow energy savings.
At present, we have smaller pacemakers, more powerful, long lasting, more versatile and more comfortable for the patient.
Traditional ventricular stimulation in the apex of the right ventricle (RV) is well known in the art, which through several years of use, it has shown an important reliance as regards permanence of the catheter in the correct place, control of the cardiac frequency and facility for its implantation. FIG. 9 illustrates a chart that shows right ventricular stimulation, "Standard Bipolar Stimulation on apex of RV". However, day after day it is proven that regardless of the fact that it keeps atrio-ventricular synchrony through stimulation of both chambers, results are far away from causing a real physiological synchrony. Right ventricular stimulation on the apex of RV generates a pattern of electric activation, asynchronous in itself and therefore asynchronous left ventricular contraction.
On the other hand, stimulation in the apex of the RV can lead to non-homogenous left ventricular contraction, myofibril erradication, and disorders of myocardic perfussion. This generates an increase in the morbidity and mortality of these patients, therefore leading from several years ago to look for other places of unique and simultaneous stimulation in order to improve electric and hemodynamic parameters of permanent stimulation.
As it can be seen novelty in pacemakers was only slightly related to the place of application of electrodes. In the new pacemaker of my invention, it can be seen as an advantage, apart from those described in the previous art, when applied on patients with pacemaker indication with preserved interventricular contraction, it prevents from deleterious effects of the traditional pacemaker over the ventricular function.
Also there are some advantages for patients with disorders in intraventricular impulse conduction and allows the re-establishment of the normal intraventricular activation sequency.
Other advantage is that in patients who suffered from heart failure with blockage in its left branch, allows me to apply well-known advantages of re-synchronization through using only one catheter, so as to obtain the electric alternative circuit procedure that we herewith call EB Electric Bypass.
As already known, traditional ventricular stimulation in the apex of right ventricle (RV) has shown along the years, great trust as regards its permanence, control of the cardiac frequency and ease for its introduction. However, day by day it has been proved that regardless the fact that it keeps atrio-ventricular synchrony through stimulation of both chambers, results are far away of causing a real phyisological synchrony. Right ventricular stimulation on apex of RV generates a pattern of electric activity, asynchronic in itself and therefore contraction and asynchronic left ventricular contraction.
On the other hand, stimulation in the apex of the RV can lead to non-homogenous left ventricular contraction, myofibril erradication, and disorders of myocardic perfussion. These disorders cause an increase in the morbidity and mortality of these patients, therefore leading from several years ago to look for other places of unique and simultaneous stimulation in order to improve electric and hemodynamic parameters of constant stimulation.
In the illustrative examples attached to the present invention its significant usefulness is shown, in presence of left ventricular dysfunction with dual-chamber (AV) pacing, resynchronizing its activity with only one catheter in RV septum, without the need of special electrophysiologist training, as seen in FIG. 9. Therefore the potential outbreak in the use of the pacemaker of the invention for constant stimulation is shown.

Apparatus for treating the physiological electric conduction of the heart


Provided herein are indole-2-carboxamide compounds useful for the treatment of non-tuberculosis bacterial infections. Exemplary compounds provided herein are useful for the treatment of non-tuberculosis mycobacterial infections. Methods for preparing the indole-2-carboxamide compounds are also provided.

Non-tuberculous mycobacteria (NTM) are opportunistic pathogens, where the prevalence of NTM pulmonary infections in the United States is increasing. Transmission of these pathogens may occur both from environmental sources and from person-to-person. The Mycobacterium avium complex (MAC) and Mycobacterium abscessus complex (MABSC) are the two species that account for the vast majority (70-95%) of global NTM infections. While MAC is still, overall, the most common cause of NTM infections in the US (accounting for over 70% of NTM pulmonary infections), over the last 10 years, rapidly-growing NTM of the M. abscessus complex (including the subspecies M. abscessus, M. massiliense and M. bolletii) have emerged as important human pathogens globally, causing an increasing number of pulmonary infections among patients with structural lung disease such as chronic obstructive pulmonary disease, bronchiectasis and cystic fibrosis (CF). MABSC species cause serious, life-threatening chronic lung disease, are responsible for disseminated, often fatal, infections following lung transplantation and are associated with a higher fatality rate than any other rapidly growing mycobacteria. Of growing concern is the report that the prevalence of MABSC infections is becoming higher than that of MAC infections in CF patients worldwide, and that MABSC infections tend to target the younger CF population and those with more severe lung disease. Depending on study site, prevalence rates of MABSC infections among children and adult CF patients range from 5% to 48%. MABSC infection in CF patients is particularly problematic as it results in accelerated inflammatory lung damage, can be impossible to treat (with 60-70% treatment failures despite years of combination therapy), and precludes lung transplantation in many US and European centers. MABSC species are indeed not only the most pathogenic rapidly growing mycobacteria, they are also the most antibiotic-resistant NTM. There are many factors that contribute to the drug resistance or drug tolerance of these microorganisms and as a result, the 2007 American Thoracic Society treatment guidelines cite no proven regimens to treat M. abscessus pulmonary infections. Current treatment recommendations include multidrug therapy with combinations of intravenous and oral antibiotics accompanied, in some cases, by surgical resection. Furthermore, most likely reflecting a defect in primary lung defense mechanisms, MABSC strains responsible for lung infections tend to co-occur with other pathogens such as Pseudomonas aeruginosa and Staphylococcus aureus.

Colorado State University Research Foundation


Lipids are used as aids in the production of solid drug forms by melt extrusion.

The present invention relates to the use of lipids as aids in the production of solid drug forms by melt extrusion.
The production of solid drug forms by melt extrusion is disclosed, for example, in U.S. Pat. No. 4,880,585, wherein the drug form is produced from the melt, which contains active ingredient and is still plastic, with the aid of a molding calender which directly molds tablets from the melt.
It has long been known that, in almost all cases when tablets are made from granules, satisfactory results are achieved only if a small amount of a lubricant is added to the formulations, after the granulation but before the tabletting, and this is deposited as a fine film on the outsides of the granule particles and thus prevents adhesion of the granules to the tabletting punches. The effect of these lubricants is very great although it is necessary to add only very small amounts to the granules (generally about 0.1 to 1% by weight; cf. H. Sucker, P. Fuchs. P. Speiser: Pharmazeutische Technologie; Georg Thieme Verlag, Stuttgart (1991), pages 259-260).
Known mold release agents for conventional processes are, for example, fatty acid esters or fatty acid salts, with only magnesium stearate normally being used in practice. Magnesium stearate is normally added to the granules which contain active ingredient and are ready before tabletting.
In the production of drug forms by melt extrusion in conjunction with a tabletting process such as calendering, it is crucial that the melt does not adhere to the surfaces of the calender rolls because, otherwise, there is no release from the molds. It also has to be taken into account in calendering to produce tablets that the compression process in the calender results in tablets which have a typical fin which is formed at the interface of the pairs of molding rolls which are in contact only at the surface. Following the calendering, this fin must be removed mechanically, generally after cooling/hardening of the melt tablets, in order to provide the tablets with a homogeneous surface structure. The success of this deflashing depends crucially on the consistency of the cooled melt containing active ingredient. This means that despite the calendering being satisfactory (no adhesion of the melt in the calender), deflashing of the resulting tablets is not necessarily possible. Many polymers form thermoplastic melts even in the presence of large amounts of active ingredients and/or ancillary substances, and these are highly flexible after cooling and can be flexed over wide ranges without breakage. In these cases, removal of the fins is very difficult and often completely impossible, although there are no problems with the extrusion and the calendering too.
Thus, it is crucial for the use of a formulation for producing tablets by melt extrusion/calendering that, besides the complete mixture having good thermoplasticity, in particular it is also possible to reduce the tendency to adhere during the calendering and control the plasticity of the cooled melt in order to ensure deflashing of the tablets.
Melt-processable cellulose derivatives such as hydroxypropylcellulose are, as water-soluble polymers, very suitable for producing tablets by solvent-free melt extrusion/calendering. It is possible by admixture of other ancillary substances, eg. HPMC (hydroxypropylmethylcellulose) polymers which are swellable in water, to control the dissolution times of such tablets in the gastrointestinal tract, as is disclosed, for example, in DE-A 4226753.
However, it has now been found that, in many cases when hydroxypropylcelluloses are used as water-soluble, thermoplastic polymer component, although the resulting melts can be extruded satisfactorily, they
a) in many cases showed an extreme tendency to adhere during the calendering,
b) did not permit removal of the fin because of excessive plasticity of the cooled melts (containing active ingredient) in the case of the calendered tablets, and
c) caused considerable problems in cleaning the extruders because of the great tendency of the melt to adhere.
It is an object of the present invention to find aids which make it possible, especially when hydroxypropylcelluloses are used as matrix polymers in the production of drug forms by melt extrusion, to solve the abovementioned problems.
We have found that this object is achieved by using lipids as mold release agents and lubricants in the production of drug forms by melt extrusion.
The lipids which are suitable according to the invention are mono-, di- and triglycerides of naturally occurring fatty acids, for example glycerol monostearate, glycerol distearate, glycerol tristearate, glycerol tripalmitate, glycerol trimyristate, glycerol tribehenate, glycerol palmitate stearate or glyceride mixtures occurring in natural oils, preferably hydrogenated castor oil.
Ceramides are furthermore also suitable for this purpose.
Preferred lipids are, in particular, phospholipids, with phosphoglycerides such as lecithins being particularly preferred. Hydrogenated lecithins such as soybean and egg lecithins are very particularly preferred.
The lipids can be used in amounts of 0.1-10%, preferably 1-5%, of the total weight of the preparations containing active ingredient.
The preparations containing active ingredient can contain as matrix polymers melt-processable polymers, for example
polyvinylpyrrolidone,
copolymers of N-vinylpyrrolidone and vinyl acetate with up to 50% by weight of vinyl acetate,
carboxyalkylcelluloses such as carboxymethylcelluloses, alkylcelluloses such as methylcellulose,
hydroxyalkylcelluloses such as hydroxymethyl-, hydroxyethyl-, hydroxypropyl- and hydroxybutylcellulose,
hydroxyalkylcelluloses such as hydroxyethylmethyl- and hydroxypropylmethylcellulose, or mixtures thereof.
Preferred polymers are hydroxypropylcelluloses and polymers based on vinylpyrrolidone.
Suitable active ingredients are all active ingredients which do not decompose under the conditions of melt extrusion.
The amount of the active component in the complete preparation can vary within wide limits depending on the activity and release rate. Thus, the content of active ingredient can be in the range from 0.1 to 90%, preferably from 0.5 to 60%, of the total weight of the preparation. The only condition is that the preparation is still melt-processable.
The preparations may furthermore contain conventional pharmaceutical ancillary substances such as bulking agents, colorants, disintegrants or stabilizers in conventional amounts.
Otherwise, the components are processed in a conventional way in extruders, preferably in single or twin screw extruders at a temperature in the range from 50 to 200xc2x0 C. The shaping of the polymer melt which contains active ingredient and is free of solvent to give the preparations according to the invention can take place, for example, by calendering the extrudate and by converting the extrudate with rotating knives into pellets which have identical volumes and have a solidified surface but are still moldable, and subsequently compressing to tablets in conventional tabletting machines.
It is possible to mix the ancillary substances into the melt or solution of active ingredients and polymers. It is furthermore possible to incorporate the ancillary substances together with the active ingredient into the polymer melt. In addition, mixtures of ancillary substances, the active ingredient and the polymers can be directly melted. It is generally customary for a physical mixture of ancillary substances, active ingredients and the polymers to be melted together.
It has been found, surprisingly, that addition of even small amounts of lipids is able to prevent adhesion of the melts containing active ingredient.
Addition of only 3% by-weight of lecithin reduces the melt adhesion of the extruded composition so much that the formulations can be calendered without restrictions. The cleaning of the extruder to remove the otherwise viscous, highly adhesive melt residues is considerably simplified because lecithin-containing formulas show scarcely any adhesion to metal and can be removed en bloc from the metal parts of the extruder which are still hot after completion of the extrusion. The plasticity of the cooled 40 melt is also beneficially affected so that deflashing of the tablets (removal of fins) takes place considerably better.

Use of lipids as adjuvents in the production of solid medicinal forms by the melt extrusion process


A computer-implemented method, system, and computer program product to optimize sleep quality by inducing sleep stages. The method includes: determining a total sleep time; calculating, using the total sleep time, a cycle duration for a sleep cycle, where the sleep cycle includes a first, second, third, fourth, and fifth sleep stage; calculating a first, second, third, fourth, and fifth stage time for the first, second, third, fourth, and fifth sleep stages respectively; generating a first, second, third, fourth, and fifth external parameter for the first, second, third, fourth, and fifth sleep stages respectively, where the external parameters are parameters to facilitate a transition between sleep stages; and executing the first, second, third, fourth, and fifth external parameters upon reaching the calculated stage time for the corresponding sleep stages.

The present disclosure relates to sleep cycles, and more specifically to optimizing sleep quality by inducing sleep stages.
Sleep cycles consist of two main types of sleep, rapid-eye-movement (REM) sleep and non-rapid-eye-movement (NREM) sleep. NREM sleep is composed of three distinct stages: N1, N2, and N3. The sleep cycle begins with NREM sleep, starting with N1, then transitioning to N2, then to N3, and then to a second N2, then to REM. A complete sleep cycle ends with REM. NREM sleep and REM sleep continue to cycle throughout the course of sleep.

Cognitively inducing sleep cycles by leveraging wearables

International Business Machines Corporation


The invention relates to a method and system for tracing a subscription in a telecommunication system. The telecommunication system comprises a local exchange, an access node connected to the local exchange, a wireless link system connected to the access node and a telecommunication terminal connected via the wireless link system to the access node. In the telecommunication system, an IMEI code corresponding to the telecommunication terminal and an IMSI code corresponding to the subscriber have been defined. In the method of the invention, the tracing of the subscription is started on the basis of the IMEI code and the tracing is converted into IMSI tracing. In the system, the access node comprises means for tracing a subscription on the basis of the IMEI code and means for converting the IMEI tracing into IMSI tracing.

The present invention relates to telecommunication systems, in particular WLL systems.
WLL system (WLL, Wireless Local Loop) refers to a system in which a subscriber is connected to a telephone network via a wireless link system. The wireless link system can be implemented using mobile communication technology, such as GSM technology (GSM, Global System for Mobile communications). The subscriber interface is implemented using a special telecommunication terminal.
In a WLL system, the subscriber""s telecommunication terminal is connected via a radio link to a telephone exchange or an access node. Between the telecommunication terminal and the telephone exchange or access node there is a base station, by means of which call signals received from the telecommunication terminal by radio are transmitted via the telephone exchange or access node further to the public telephone network and vice versa. The access node is connected to the telephone exchange e.g. using a V5.1 or V5.2 protocol.
Open interfaces (V5.1 and V5.2) between an access node and a telephone exchange are defined in the ETSI (European Telecommunications and Standards Institute) standards. V5 interfaces enable subscribers belonging to a physically separate access network, which may be a wired or a wireless network, to be connected using a standard telephone exchange interface.
Call tracing is a necessary function in the WLL system. Tracing is used to collect information about call-time events related to a given subscriber, such as the radio channel used, power level, location, call setup direction, duration or start time. The call tracing function can be used to locate faults in the wireless link system, to locate stolen terminals or mischief caused in the network via a terminal, or to prevent illicit use of a terminal.
Previously known tracing methods used in the GSM system are those based on IMSI and IMEI. According to its definition, IMSI (International Mobile Subscriber Identity) is a code consisting of the mobile subscriber""s national identity code and a mobile communication country code, allowing unambiguous identification of the mobile subscriber. Where card-controlled telecommunication terminals are used, the international mobile subscriber identity code is card-specific, in other words, the user is identified on the basis of the SIM card (SIM, Subscriber Identity Module) placed in the telecommunication terminal and not on the basis of the terminal device itself. IMEI (International Mobile station Equipment Identity) is a code by which the telecommunication terminal can be unambiguously identified. The ETSI standard describes both IMSI and IMEI based tracing methods. Managing all the information generated as a result of different types of tracing is a complicated task which occupies resources of both the network management system and the operator. The operator must have separate means for IMSI and IMEI tracing procedures. Thus, both the means and the associated training for their use are a source of expenses to the operator.
The object of the present invention is to solve the problems described above. A specific object of the invention is to disclose a new type of method and system for tracing subscriptions in a WLL system.
The invention relates to a method for tracing a subscription in a telecommunication system comprising a local exchange, an access node connected to the local exchange, a wireless link system connected to the access node and a telecommunication terminal connected to the access node via the wireless link system. Moreover, an IMEI code corresponding to the telecommunication terminal and an IMSI code corresponding to the subscriber are defined in the telecommunication system. In the method of the invention, the access node starts the tracing of a subscription on the basis of the IMEI code and converts the tracing into an IMSI tracing procedure, so that the means intended for tracing in the access node only see the IMSI tracing procedure. In an embodiment of the invention, a reference number is generated on the basis of IMEI tracing and this number is linked with the IMSI tracing. The IMEI tracing is preferably activated for a telecommunication terminal listed in the equipment register of the access node as a device to be traced.
In a preferred embodiment, a tracing report is generated which comprises the IMEI code, IMSI code and reference number. The IMSI code corresponding to the IMEI code is preferably retrieved from a subscriber data register. The IMSI code may also be taken from the call initiating messages. In an embodiment, an alarm is generated in conjunction with a call by a terminal without a subscriber identity module, in which case e.g. the IMEI code, location area and call event of the telecommunication terminal are presented in conjunction with the alarm.
In an embodiment of the method, the wireless link system is based on a digital mobile communication system, such as the GSM system.
Moreover, the invention concerns a system for the tracing of a subscription in a telecommunication system as described above. In the system of the invention, the access node comprises means for tracing a subscriber on the basis of the IMEI code and means for converting the tracing into an IMSI tracing procedure. In an embodiment, the access node comprises means for generating a reference number based on IMEI tracing and for linking the reference number with the IMSI tracing procedure. The access node preferably comprises an equipment register in which the telecommunication terminal subject to IMEI tracing is entered.
In a preferred embodiment of the system, the access node comprises means for generating a report. The report may include the IMEI code, the IMSI code and the reference number. A system according to the invention comprises a subscriber data register comprised in the access node, said register containing the IMSI code corresponding to the IMEI code. The access node preferably comprises means for obtaining the IMSI code from the call initiating messages, allowing it to be transferred to the subscriber data register.
In an embodiment, the access node comprises means for generating an alarm from a call by a telecommunication terminal without a subscriber identity module, the alarm comprising e.g. the IMEI code and location area and call event of the telecommunication terminal.
In an embodiment of the system, the wireless link system used is based on a digital mobile communication system, such as the GSM system.
The invention allows easier processing of the tracing data collected by an access node because it is now possible to utilize IMSI tracing operations and means. In the system, there is no need for separate IMEI tracing follow-up processing and associated equipment. In this way, system capacity is made available for other operations and efficiency is maximized. In addition, the consistency in IMEI and IMEI tracing procedures renders the operator""s work easier.

Method and system for tracing a subscription


A method for identity (ID) verification, including:

The present invention, in some embodiments thereof, relates to identity verification and, more particularly, but not exclusively, to identity verification of medical objects.
U.S. Pat. No. 4,857,716 describes "a patient identification system for relating items with patients and ensuring that an identified item corresponds to an identified patient. The patient identification system includes a computer system (42) interconnected to a plurality of remote terminals (62) by conventional telephone wiring (66,70). The patient identification system further including a portable bar code reading device (48) including a bar code wand (120), an LCD display (116) and a key pad (114). The portable bar code reading device (48) communicates via RF transmission with an RF/PLC modem (60). The bar code reading device (48) is utilized to read a patient's unique bar codes (50) on a patient's identification bracelet (52), bar codes (51) on labels (53) attached to various items in the hospital relating the item to a specific patient and bar codes (49) on item labels (47) whereby such items can be automatically correlated to a specific patient and checks performed at the computer system (42) to ensure that the item properly corresponds to the identified patient".
Additional background art includes U.S. Pat. Nos. 4,122,947, 3,848,112, 8,308,640 B2, and 4,476,381.

Abstract: acquiring one or more ID indications of at least one item using a hand held verifying device;

Abstract: automatically verifying by the verifying device a desired relation between the one or more acquired ID indications and stored verification data associated with the verifying device;

Abstract: physically marking the item using the verifying device with a verifying marking if the desired relation is automatically verified.

Fund for Medical Research Development of Infrastructure & Health Services by Barzilai Medical Center


The present invention relates to a hair treatment preparation and a method of use thereof. The hair treatment preparation is in the form of an oil-in-water emulsion and is preferably used for reducing split ends. The hair treatment preparation contains a lipid soluble ester alcohol or ester polyol and a water-soluble compound selected from panthenol, a panthenol derivative, nicotinic acid amide, a sugar, polyvinyl pyrrolidine or mixtures thereof.

This application is a 371 of PCT/EP98/05631 filed Sep. 5, 1998.
This invention relates to hair treatment preparations in the form of an oil-in-water emulsion containing a particularly effective combination of lipid-soluble and water-/soluble active substances capable of reducing split ends.
Split ends/are a phenomenon which manifests itself in the hair fibers becoming porous and in splitting of the individual hairs from their ends. Split ends are caused inter alia by severe mechanical stressing of the hair, for example by frequent brushing, back-combing or combing against high combing resistance. High combing resistance in dry hair can be caused by damage to the hair surface, static charging or tackiness attributable to residues of hair sprays. The danger of split ends is also increased by weakening of the hair structure which can be caused by frequent or careless application of chemical treatments, as for example in permanent waving or coloring.
Accordingly, there has been no shortage of attempts to regenerate hair damaged by split ends by applying suitable preparations, i.e. to stop the advance of split ends and to repair the split hairs.
DE 195 14 268 describes cosmetic preparations containing ester polyols which, when applied to the hair, are capable of increasing its tear strength. There is no reference in this document to the regeneration of split ends.
DE 37 11 841 A1 discloses hair-regenerating preparations which contain, for example, panthenol or glucose, optionally in combination with polyvinyl pyrrolidone, as water-soluble active substances for reducing split ends.
It was known from DE 44 40 315 A1 that combinations of mono- or oligosaccharides and derivatives thereof with cationically derivatized panthenol are capable of regenerating split hairs.
Although the last of the compositions mentioned above reduces the number of split ends in damaged hair, the effect is not entirely satisfactory in the case of products which are rinsed off from the hair after application (so-called rinse-off products), such as for example shampoos and hair rinses.
Accordingly, the problem addressed by the present invention was distinctly to improve hair treatment preparations in regard to their effectiveness in repairing split ends. This problem has to be solved to a particularly high degree by the split-end-regenerating hair treatment preparations according to the invention.
The present invention relates to hair treatment preparations in the form of an oil-in-water emulsion, characterized in that they contain 0.1 to 10% by weight of a lipid-soluble ester alcohol or ester polyol obtainable by reacting an epoxyfatty acid ester with a mono- or polyhydric alcohol containing 1 to 6 carbon atoms as a component of the oil phase and
0.1 to 3% by weight of a known, split-end-reducing water-soluble compound from the group consisting of panthenol, nicotinic acid amide, sugar, polyvinyl pyrrolidone or mixtures thereof as a component of the aqueous phase
as ingredients active in reducing split ends.
Preparations in the context of the invention are both leave-on products, such as setting lotions, styling aids and hair conditioners, and rinse-off products, i.e. products which are rinsed off from the hair after application, such as for example shampoos, hair aftertreatments, permanent wave fixing lotions or, for example, hair colorants.
The only important requirement is that the preparations contain an emulsified oil phase, i.e. are present in the form of an oil-in-water emulsion or microemulsion.
The lipid-soluble ester alcohols or ester polyols are known from the literature and are commercially obtainable products. They may be regarded as lipid-soluble when 5% by weight of these products dissolve clearly in cetyl alcohol at 80xc2x0 C.
The ester alcohols or ester polyols suitable for use in accordance with the invention are obtainable by reacting an epoxyfatty acid ester with water or mono- or polyhydric alcohols containing 1 to 10 carbon atoms which opens the epoxide ring and forms a vicinal dihydroxyethyl or hydroxyalkoxyethyl group. The epoxy fatty acid ester may even be an epoxidation product of a technical fatty acid ester containing saturated fatty acids. However, the epoxide oxygen content should be at least 3% by weight and is preferably in the range from 5 to 10% by weight.
The epoxyfatty acid esters are either epoxidized fatty acid esters of monohydric alcohols, i.e. for example epoxidized oleic acid methyl ester, linoleic acid methyl ester, ricinoleic acid methyl ester, or epoxidized fatty acid esters of polyhydric alcohols, for example glycerol monooleate or propylene glycol monooleate, or epoxidized fatty acid triglycerides, for example oleic acid triglyceride, or unsaturated oils such as, for example, olive oil, soybean oil, sunflower oil, linseed oil, rapeseed oil.
Of particular technical interest are, above all, unsaturated fatty acid methyl ester epoxides of unsaturated vegetable fatty acids. Thus, a particularly preferred ester polyol is the reaction product of a vegetable oil fatty acid methyl ester epoxidate with a polyol containing 2 to 6 carbon atoms and 2 to 6 hydroxyl groups. The polyols present may be, for example, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, butanediol, pentanediol, hexanediol, glycerol, trimethylol propane, pentaerythritol, sorbitol or diglycerol.
The reaction product of a vegetable fatty acid methyl ester epoxidate with trimethylol propane with a hydroxyl value of 350 to 450 is a particularly suitable ester polyol for the hair treatment preparation according to the invention. One such product based on soya fatty acid methyl ester epoxide and trimethylol propane is commercially obtainable as Sovermol(copyright).
The present invention also relates to the use of ester polyols obtainable by reacting epoxyfatty acid esters having an epoxide oxygen content of at least 3% by weight with water or a mono- or polyhydric alcohol containing 1 to 10 carbon atoms as lipid-soluble substances active in reducing split ends in combination with water-soluble split-end-reducing compounds in hair treatment emulsions.
Known water-soluble split-end-reducing compounds which may be present are, for example, sugars, i.e. mono- and disaccharides. Suitable monosaccharides are, for example, glucose, fructose, mannose and deoxy sugars such as, for example, fucose or rhamnose. Suitable disaccharides are, for example, sucrose, cellobiose, lactose or maltose.
Another water-soluble compound active in reducing split ends is nicotinic acid amide which is preferably used in a quantity of 0.01 to 1% by weight. Nicotinic acid amide, also known as vitamin B3, has been described as a topical deodorant and also as a topical agent for preventing hair loss. Effectiveness in reducing split ends when externally applied to hair has not hitherto been observed.
Other known water-soluble split-end-reducing agents are panthenol and derivatives thereof, for example the cationically derived Panthequat(copyright)) (CTFA name: Panthenyl-hydroxypropyl-steardimoniumchloride) and polyvinyl pyrrolidone. These water-soluble compounds are preferably used in combination. The hair treatment preparations according to the invention preferably contain 1 to 2% by weight of a sugar and 0.1 to 1% by weight of panthenol.
A combination of panthenol and nicotinic acid amide is also preferably present as water-soluble active substance in the preparations according to the invention. The ratio by weight between these two water-soluble xe2x80x9cantisplitxe2x80x9d agents may be between 1:1 and 10:1.
The hair treatment preparations according to the invention may additionally contain any of the usual auxiliaries and carrier components typically used for the particular application.
These are first and foremost the oil and fatty components and emulsifiers required for emulsion-like preparations.
The oil or fatty components normally used are paraffins or paraffin oils, natural or synthetic fatty acid esters, silicone oils, fatty alcohols or di-n-alkyl ethers. For hair aftertreatment preparations, C14-22 fatty alcohols for example, more particularly cetyl and stearyl alcohol, are greatly preferred fatty components. However, fatty acid esters such as, for example, isopropyl myristate, n-hexyl laurate or n-decyl oleate, synthetic triglycerides such as, for example caprylic/capric acid triglyceride or natural triglycerides such as, for example, refined vegetable oils are also used for such purposes.
Preferred oil components for the production of microemulsions are the di-n-alkyl ethers, for example di-n-octyl ether.
Suitable emulsifiers are anionic, zwitterionic, cationic or nonionic surfactants. The cationic surfactants have the advantage that they counteract the static charging of hair and, in doing so, contribute towards improving combability and reducing split ends.
In addition, it is known that cationic surfactants are suitable for the production of very low-viscosity fatty alcohol dispersions and that quantities of only 0.1 to 1 part by weight of cationic quaternary ammonium surfactants are sufficient for stabilizing a dispersion of 10 to 25 parts by weight of cetyl or stearyl alcohol.
Mixtures of paraffin oils, fatty alcohols and optionally fatty acid esters are preferably used as oil components. In such cases, mixtures of cationic and nonionic surfactants are also generally used as emulsifiers. Suitable cationic surfactants are, for example, cetyl trimethyl ammonium chloride and distearoyloxyethyl hydroxyethyl methyl ammonium methoxysulfate. Suitable nonionic emulsifiers are, for example, products of the addition of 10 to 30 moles ethylene oxide onto C16-22 fatty alcohols, fatty acid monoglycerides, sorbitan fatty acid monoesters or methyl glucoside fatty acid monoesters. Other suitable nonionic emulsifiers are, for example, fatty acid polyglycerol esters and mixtures thereof with methyl glucose fatty acid esters or alkyl (oligo)glycosides. The latter are preferably used for the production of microemulsions of the oil-in-water type.
In addition, fatty acid mono- or diglycerides, sorbitan fatty acid esters or propylene glycol monofatty acid esters, for example, are used as oil-soluble co-emulsifiers.
In addition, the emulsions may be viscosity-adjusted, i.e. thickened, with the water-soluble polymers and cellulose derivatives normally used for this purpose. Anionic polymers should not be used in combination with cationic surfactants because of possible interaction. Nonionic polymeric thickeners, for example methyl hydroxypropyl cellulose, hydroxypropyl guar, polyvinyl pyrrolidone and hydroxyethyl starch, are preferably used.
Other auxiliaries which may be present in the hair treatment preparations according to the invention to develop special hair-care effects are, for example,
structurants, for example maleic acid,
setting polymers,
hair-conditioning compounds, for example phospholipids, for example soya lecithin, kephalins, silicone oils, proteins or protein hydrolyzates, cationic water-soluble polymers, quaternized protein hydrolyzates, plant extracts, allantoin, pyrrolidone carboxylic acid salts, vitamins,
antidandruff agents such as, for example, Zinc Omadine, Piroctone Olamine, salicylic acid and other antimycotic agents active against Pityrosporum ovale,
light filters (UV absorbers),
hair dyes or dye precursors,
oxidizing agents for permanent wave fixing, for example alkali metal bromates, hydrogen peroxide.
The emulsions may additionally contain the usual carriers and formulation aids necessary for stability, viscosity, appearance, odor and application, for example
solvents and solubilizers, for example lower alcohol, glycols, glycerol, diethylene glycol, polyethylene glycol,
dyes, opacifiers and pearlizers,
pH regulators and buffers, for example citric acid/stearate,
complexing agents, for example acetophosphonates, EDTA or NTA,
preservatives, for example pheoxyethanol, p-hydroxybenzoates,
perfumes,
antioxidants and
aerosol propellent gases.
The following Examples are intended to illustrate the invention.

Hair conditioners for treating split ends