Losartan potassium is an angiotensin II antagonist useful in the treatment of hypertension and congestive heart failure. ##STR1## This invention relates to the process for the controlled crystallization of losartan potassium utilizing anti-solvent addition combined with massive seeding in order to obtain the desired crystal morphology and bulk physical properties necessary for successful formulation.

Losartan potassium also known as 2-butyl-4-chloro-1-(2'-tetrazol-5-yl)-biphenyl-4-yl!methyl!-5-(hydroxymet hyl)imidazole potassium salt has been approved for the treatment of hypertension.
Losartan is known to inhibit the action of the octapeptide hormone angiotensin II (AII) and is useful therefore in alleviating angiotensin induced hypertension. The enzyme renin acts on a blood plasma .alpha..sub.2 -globulin, angiotensinogen, to produce angiotensin I, which is then converted by angiotensin converting-enzyme to AII. The latter substance is a powerful vasopressor agent which has been implicated as a causitive agent for producing high blood pressure in various mammalian species, such as the rat, dog, and man. Losartan inhibits the action of AII at its receptors on target cells and thus prevents the increase in blood pressure produced by this hormone-receptor interaction. By administering losartan to a species of mammal with atherosclerosis and/or high cholesterol and/or hypertension due to AII, the blood pressure is reduced. Losartan is also useful for the treatment of high cholesterol by reducing the total cholesterol. Administration of losartan with a diuretic such as furosemide or hydrochlorothiazide, either as a stepwise combined therapy (diuretic first) or as a physical mixture, enhances the antihypertensive effect of losartan, while also treating atherosclerosis and reducing cholesterol levels. Administration of losartan with a non-steroidal anti-inflammatory drug (NSAID) can prevent renal failure which sometimes results from administration of a NSAID.

Process for the crystalization of losartan


Combustion residues of a gas generating agent remain in an inflator due to composition of the gas generating agent, temperature difference between combustion gas and pressurized gas isolated by a rupturable plate, collision of the combustion gas against a wall surface and the like. The inflator inflates an air bag with pressurized gas and combustion gas, while satisfying the following requirements: (1) pressurized gas contains an inert gas and substantially no oxygen; (2) in the gas generating agent, a pressure is 0.8 or less; (3) a mole ratio of an amount of pressurized gas and the combustion gas is 1 to 10; (4) a ratio of a mass of pressurized gas and the gas generating agent is 1 to 10; (5) a mass of a gas generating agent is 1 to 30 g; and (6) the pressurized gas is charged at 30,000 to 67,000 kPa.

1. Field of the Invention
The present invention relates to an inflator suitable for an air bag system for an automobile. The present invention also provides an inflator in which pieces of a broken rupturable plate or combustion residues of a gas generating agent are prevented from flowing out of the inflator.
2. Description of the Related Art
As an inflator used in an air bag system for an automobile, there is a type in which an air bag is inflated by using only combustion gas of a gas generating agent and also a type in which an air bag is inflated by using combustion gas of a gas generating agent and pressurized gas. In either type of inflators, it is required that combustion residues generated at the time of combustion of the gas generating agent, for example, powdery metal or metal oxide generated due to components of the gas generating agent are never discharged into the air bag. Therefore, such a trial has been made that generation of combustion residues is suppressed by changing composition of the gas generating agent or a structure of the inflator.
In addition, there is a type in which an air bag is inflated by using only pressurized gas. However, with a development of an inflator for an inflating-type safety system for an automobile, an inflator using pressurized gas and a gas generating agent together is attracting attention.
Also, such a trial has been made that a filter is disposed to prevent pieces of a broken rupturable plate from flowing outside, or that generation of combustion residues is suppressed by changing composition of the gas generating agent, or a structure of the inflator.
As related art, there are JP-A 9-76870, U.S. Pat. No. 3,966,226, and U.S. Pat. No. 4,018,457.
An essential requirement in designing the inflator is that an air bag has to be inflated by a predetermined amount within a predetermined time to actuate the air bag effectively, and various proposals about the structure have been made conventionally. For example, there is JP-A 8-282427. As other related art, there have been known JP-B 44-10443, U.S. Pat. No. 6,189,922, and JP-A 2002-166817.
Since the inflator is installed in an automobile, the weight and size of the inflator which influences a weight of an automobile are important design requirements. Accordingly, further reduction in weight of an inflator is required while maintaining its original functions.


An image forming device includes a casing having a guide, image forming portions configured to form images on a recording medium, and a drawer configured to be installed in and withdrawn from the casing along the guide in a first direction for installation and in a second direction for withdrawal opposite the first direction. The drawer may include a housing configured to house each image forming portion, a projecting portion coupled to the housing and protruding in the first direction, and a support portion coupled to the projecting portion. An engagement of the support portion with the guide regulates movement of the drawer upward or downward during installation and withdrawal.

Tandem style color laser printers are known for their use as image-forming devices in electrophotography. For example, the laser printer described in Japanese Patent Application Publication No. 2003-107838 is equipped with several image-forming portions including a photosensitive drum, developing device, charger, etc. that are housed inside the main unit casing. Each of the image-forming portions is housed in a drawer and is configured so that the drawer can be drawn out from the main unit casing and the developing device can be replaced.
Such an image-forming device often have guiding walls that extend from the front to the back inside the main unit casing and which are used to guide the insertion and removal of the drawer. Additionally, when the drawer has been removed, support portions that are positioned at the rear of the drawer come into contact with the downward-facing surfaces of the guiding walls so that the guiding walls bear the upward load from each support portion and vertical inclination of the drawer is limited.
However, when parts in the drawer are heavy, the load on the support portions increases when the drawer is pulled out making it more difficult to insert or remove the drawer. As a countermeasure, it is conceivable that locating the support portions closer to the rear would reduce the load on the support portions. However, when the drawer is extended rearward to locate the support portions farther back, the device increases in size.

This patent is subject to a terminal disclaimer.

Image-forming device and process cartridge configured to be installed in and removed therefrom


A fuse comprising: a fusible portion constituted by a connection portion which is formed of the same metal base material as a pair of terminals so as to connect the pain of terminals to each other, and a low-melting metal having a melting point lower than that of the connection portion and stacked by welding on at least a portion of the connection portion; and at least one protrusion formed on the fusible portion by making the connection portion and the low-melting metal project in a direction parallel to the plane of an interface between the connection portion and the low-melting metal. Further disclosed is a method of manufacturing the fuse. The fuse can be manufactured with a simple manufacturing process in comparison with a conventional method, and in the fuse, only the fusing-off time in a layer short-circuit range can be shortened by use of diffusion between the low-melting metal and base material.

The present invention relates to fuses for protecting electric wires, equipments and so on from an overcurrent.
In electric circuits of automobiles or the like, conventionally, fuses were used to protect electric wires, equipments and so on from an overcurrent. JP-A-7-130277 discloses such a fuse in which a thin extension portion is formed in a fusible portion to improve the effect of collecting heat so as to obtain superior fusing-off property. In this fuse 1, as shown in FIG. 1, base portions 5 are provided on a pair of terminals 3 and 3 so as to project therefrom, and caulking protrusions 7 are provided at these base portions 5. The base portions 5 are connected to each other through a slender extension portion 9. After the opposite ends of a low-melting chip are fixed by the caulking protrusions 7, the low-melting chip is heated so as to be melted once, so that cohesive portions 13 and 13 which are a pair of increased-sectional-area portions are formed around the caulking protrusions 7 by the surface tension, while a thin extension portion 15 is formed at the center of the slender extension portion 9.
According to the thus configured fuse 1, the sectional area of the slender extension portion 9 is smaller than the sectional area of each of the cohesive portions 13 and 13 so that a sufficient constriction rate can be obtained. By the heat collecting effect of the constriction, it is easy to specify the position of a fusing portion and reduce a heating area. Accordingly, it is possible to specify a hot spot position and reduce a heating area, so that not only it is possible to restrain a fuse element from heating as a whole so as to reduce unnecessary heat transfer to the terminals 3 and 3 of a housing not shown and the surroundings thereof, but also it is possible to obtain superior fusing-off property in a low current range by effective use of heating.
However, generally, a fuse has a constant correlation between current conduction and fusing-off time. That is, while a fusible portion of a fuse element is fused off immediately in the case of short (dead short-circuit), for example, caused by a current of 200% or more of the rated current of the fuse, the fusible portion repeats heat generation and radiation in the case of a short-circuit caused by a current of 200% or less of the rated current of the fuse or in an intermittent short-circuit (layer short-circuit), so that there is a tendency to increase the fusing-off time. Under such conditions, electric wires constituting a circuit do not radiate heat as the fusible portion due to an insulating coating covering it even if the intermittent short current flows in the wires. Therefore the temperature continues to increase because of heat accumulation, and there is a fear that smoking or the like may be caused in the worst case.
For solving such a problem, there is a method in which a base material of a fuse element is diffused into low-melting metal to make the fusing-off temperature lower than the melting point of the base material to thereby shorten only the fusing-off time in a layer short-circuit range without changing the fusing-off property in a dead short-circuit range so as to improve the fusing-off property in the layer short-circuit range.
Since the thin extension portion 15 is formed at the center of the fusible portion in the above-mentioned conventional fuse 1 in order to increase the constriction rate, it is possible to obtain a heat collecting effect based on the constriction. It is, however, impossible to obtain a sufficient fusing amount of the low-melting metal, and it is therefore difficult to obtain an effect to shorten the fusing-off time on the basis of the diffusion.
In addition, in the above-mentioned conventional fuse 1, a low-melting chip is caulked by the caulking protrusions 7 after the terminals 3 and 3, the base portions 5 and the slender extension portion 9 are formed by pressing, and the low-melting chip is heated and melted to be welded to the slender extension portion 9. There is, therefore, a problem that the steps of coating with flux before welding, caulking, heating and melting the low-melting chip, cleaning the flux after welding, and so on are complicated so that the manufacturing cost is high.

Fuse and method of manufacturing the same


A whipstock that is totally to substantially non-metallic is made preferably from a composite material. The body can include one or more stiffeners that are also preferably non-metallic. The mounting lug for the window mill can also be non-metallic. A metallic base can be used to connect to an anchor. Optionally the ramp can include a plate that is optionally internally supported. Alternatively the ramp can include hardened inserts or other wear resistant material. Composite materials that can be molded are preferred.

Frequently in the life of a well additional laterals are needed to properly and more fully produce a formation. Whipstocks are properly positioned in the wellbore and oriented so that the lateral will exit in the proper direction into the target formation. Whipstocks are typically anchored from below and feature a ramp surface in the range of about 3 degrees. As a result the whipstock body is generally fairly long and features a lug near its upper end to allow a window mill to be delivered with it. After proper orientation and anchoring, the window mill is started and it breaks loose from its mounting lug and begins to make the exit or window in the surrounding tubular.
The whipstocks are typically milled from a metal cylinder stock in a process that takes a great deal of time to mill away a ramp that can be over 15 feet long. The resulting rigidity of the whipstock also makes it difficult to manipulate it in deviated wellbores and risks breaking the connection between the window mill and the lug when running in.
Whipstocks have always been made this way. The present invention is a departure from this tradition in that it results in a streamlined manufacturing process that is easier to run in and yet comparably performs to the traditional totally metallic designs. Examples of the whipstocks now in use are illustrated in U.S. Pat. Nos. 6,766,859; 6,497,288; 6,419,024; 6,419,023; 6,419,021; 6,419,012; 6,419,010; 6,386,287; 5,725,060; 5,507,346; 5,499,680; 5,467,820; 5,277,251; 5,199,513 and US Publication Number 2002/0029889. The last reference shows the use of a polymeric coating on the whipstock to protect its metal body and to ease the advancement of a washover tool over the top of the whipstock if it needs to be retrieved.
Apart from the prior art mentioned above, an older technique presents an alternative to milling a whipstock from a metal cylinder. FIGS. 1-3 illustrate the method. A tubular 10 gets a half circumferential cut 12 and two opposed tapered cuts 14 and 16. The cut piece 18 is removed and inverted, as shown in FIG. 3 and welded back into position and the result is a ramp to an opening 20. One disadvantage here is the presence of a piece of the tubular 22 that has an internal diameter 24 which can limit the diameter of the window mill that can fit though and still make the turn on the ramp formed by cut piece 18. FIG. 4 shows a typical milled whipstock 26 that has a retrieval slot 28 and a lug 30 for initial support from a window mill 32. The window is produced in the tubular 34.
The present invention will be more readily understood by those skilled in the art from the discussion of the preferred embodiment and the related drawings and from the claims that define the scope of the invention.


Prepolymers which contain isocyanate groups, have an NCO content of at least 30.0% by weight and can be prepared by reacting an isocyanate mixture consisting predominantly of diphenylmethane diisocyanates and polyphenylpolymethylene polyisocyanates and having a proportion of two-ring isomers of not more than 74% by weight with at least 4-functional polyols or a mixture of polyols having a mean functionality of at least 4, where the polyols or polyol mixtures have a hydroxyl number of from 200 to 1650 mg KOH/g and a number average molecular weight of less than 1100 g/mol. The present invention also provides a process for preparing these prepolymers containing isocyanate groups, provides for their use for producing polyurethanes and provides a process for producing polyurethanes by reacting at least one novel prepolymer containing isocyanate groups, if desired in admixture with further organic and/or modified organic isocyanates (a), with compounds having at least two reactive hydrogen atoms (b) in the presence of, if desired, blowing agents (c), catalysts (d) and, if desired, further auxiliaries and/or additives (e).

The present invention relates to novel prepolymers containing isocyanate groups, a process for their preparation by reacting an isocyanate mixture consisting predominantly of diphenylmethane diisocyanates and polyphenylpolymethylene polyisocyanates with polyols or a mixture of polyols and the use of these prepolymers for producing polyurethanes, in particular polyurethane foams.
The production of polyurethanes, including polyurethane foams, by reacting organic polyisocyanates and/or modified organic polyisocyanates or prepolymers with higher-functionality compounds containing at least two reactive hydrogen atoms, for example polyoxyalkylenepolyamines and/or preferably organic polyhydroxyl compounds, in particular polyetherols having molecular weights of, for example, from 200 to 6000, and, if desired, chain extenders and/or crosslinkers having molecular weights of up to about 400 in the presence of catalysts, blowing agents, auxiliaries and/or additives is known and has been described many times. A summary overview of this is given, for example, in the Kunststoff-Handbuch, Volume VII, xe2x80x9cPolyurethanexe2x80x9d, 1st Edition 1966, edited by Dr. R. Vieweg and Dr. A. Hxc3x6chtlen, and 2nd Edition 1983 and 3rd Edition 1993, edited by Dr. G. Oertel (Carl Hanser Verlag, Munich, Vienna).
The chemical structures which are formed from the polyisocyanates and are present here can be polyurethanes, polyureas, polyisocyanurates and also further isocyanate adducts such as allophanates, biurets, carbodiimides and the isocyanate adducts, oxazolidones, polyimides, polyamides, etc. The type of these structures is controlled by means of the compounds which are reacted with the isocyanates, the catalysis and the reaction conditions. These isocyanate adducts are generally summarized under the term polyurethanes since the polyurethanes are the most important and most frequent of the polyisocyanate adducts.
The preparation of NCO prepolymers has also been described in numerous documents, for example in the abovementioned Kunststoff-Handbuch.
For foam production, it is useful if the foam bodies can be quickly removed from the mold immediately after their production. This applies both to removal from a mold in batchwise foam production and to the continuous production of foams, for example using the double conveyor belt method. It is important that the demolding itself takes place without crack formation and/or the foam can, as a result of correspondingly good curing, be subjected as quickly as possible after the synthesis to mechanical treatment, e.g. a sawing step, without crack formation or other destructive occurrences. The foams should have a fine-celled structure. In addition, the flow behavior of the reacting mixture of isocyanate and hydrogen-active materials is of particular importance for foam formation. This flow behavior is, as is known, influenced by the viscosity of the components and thus also of the isocyanate components. A low viscosity of the isocyanate component is necessary for good flow. The required better curing with low crack formation can be achieved in a known manner by, for example, use of a relatively high-viscosity isocyanate having a low proportion of diphenylmethane diisocyanates and a relatively high proportion of polyphenylpolymethylene polyisocyanates. This does not meet the requirement of reducing crack formation at a given constant viscosity of the isocyanate component, i.e. improving the curing immediately after foam formation.
EP-A-0 543 536 describes the production of foams in the presence of a liquid which is largely insoluble in the reaction mixture and is present as an emulsion or microemulsion. This emulsion is said to lead to a more fine-celled structure of the foam. Isocyanate components described for this specific purpose are, apart from customary mixtures of diphenylmethane diisocyanates with polyphenylpolymethylene polyisocyanates, also prepolymers derived from these mixtures and a bifunctional, isocyanate-reactive component in a range from 1 to 150 millimol of urethane/100 g.
WO 93/08224 describes a polyisocyanate composition as a mixture of from 30 to 85% by weight of NCO prepolymer, up to 50% by weight of polyphenylpolymethylene polyisocyanates and up to 40% by weight of diphenylmethane diisocyanates. The advantage indicated is an improved miscibility with rigid foam polyols. For this purpose, considerable parts of the NCO groups are reacted with polyols having a molecular weight from 11,000 g/mol upward, so that NCO contents of the prepolymer far below 30% by weight, in preferred examples from 18.1 to 19.8% by weight, are always obtained. These prepolymers give cells which are still too large in the rigid foam and lead to unsatisfactory curing.
DE-A-4118362 describes the production of pipe insulation via rigid foam having an external compact polyurethane covering layer. Among other things, NCO prepolymers derived from diphenylmethane diisocyanates containing up to 30% by weight of polyphenylpolymethylene polyisocyanates and having an NCO content of the prepolymers of from 5 to 20% by weight are also used.
U.S. Pat. No. 5,164,422 describes the production of polyisocyanurate foams using prepolymers derived from polymeric diphenylmethane diisocyanates and polyester alcohols having a functionality of significantly below 4.
EP-A-0 392 788 discloses a prepolymer derived from diphenylmethane diisocyanates for the production of purely water-blown foams; this prepolymer has an NCO content of from 2 to 12% by weight of NCO. The viscosity is too high for normal foam processing, namely 38,000 mPas in a preferred example.
EP-A-0 320 134 describes prepolymers derived from diphenylmethane diisocyanates and polyols having a functionality of significantly below 4 as constituents of a mixture with diphenylmethane diisocyanates and polyphenylpolymethylene polyisocyanates for producing rigid foam.
AU 8767-425 describes the use of prepolymers derived from a mixture of from 45 to 95% by weight of diphenylmethane diisocyanates and from 5 to 55% by weight of polyphenylpolymethylene polyisocyanates and polyester polyols having a mean functionality of significantly less than 4, the prepolymers having an NCO content of significantly less than 30% by weight for producing flexible foam having excellent adhesion to PVC.
SU 876 657 describes the use of a prepolymer derived from a mixture of from 75 to 65 parts of diphenylmethane diisocyanates with from 25 to 35 parts of polyphenylpolymethylene polyisocyanates and triols for integral rigid foam.
NL 7605 286 describes the use of a prepolymer derived from diphenylmethane diisocyanates in admixture with their uretoneimines and diols.
DT 2513 793 and DT 2513 796 describe the use of a prepolymer derived from a mixture of from 55 to 85 parts of diphenylmethane diisocyanates with polyphenylpolymethylene polyisocyanates and diols.
In EP-A-0 550 901, isocyanates of the diphenylmethane series having a proportion of from 75 to 95% by weight of two-ring isomers with a proportion of 2,4xe2x80x2-isomers of from 15 to 40% by weight and of 2,2xe2x80x2-isomers of from 2 to 10% by weight and also a proportion of from 5 to 25% by weight of polymeric isocyanates of the diphenylmethane series are reacted with polyether polyols having a functionality of from 3 to 8, and an OH number of from 350 to 1000 mg KOH/g and a molecular weight of from 150 to 1000 g/mol. The main object of this invention is the preparation of light-colored isocyanate components from which particularly light-colored rigid polyurethane foams can then be produced.
In WO 94/29361 prepolymers having NCO contents of from 5 to 10% by weight are produced by reacting isocyanates with polyols at from 40 to 80xc2x0 C., with the reaction being carried out conventionally, i.e. in a reaction vessel suitable for this purpose.
U.S. Pat. No. 5,114,989 discloses, for example, MDI prepolymers which are reacted with polyols rich in ethylene oxide. It is stated here that the metered addition of polyol to the initial charge of isocyanate in the reactor has to be carried out so that a temperature in the range from 45 to 90xc2x0 C. is maintained or not exceeded.
DE-A-4202972 describes a continuous preparation of a prepolymer using a special mixing nozzle. In actual fact mixing is achieved by means of a mixing head of a polyurethane foaming machine. This continuous reaction takes place in a separate unit.
EP-A-0 480 588 and EP-A-0 722 962 describe a continuous production of isocyanate prepolymers where an existing foaming plant is, when the foaming plant is down, utilized as far as the mixing head for continuously metering the components for the preparation of the prepolymers. During this time, the entire foaming plant cannot be used for its actual purpose, which has to be seen as a disadvantage.
Experiments on producing prepolymers continuously in a reaction extruder have been described (DE-A-2842806).
DE-A-2302564 discloses special mixing nozzles which are supposed to produce intimate mixing of the components and such a mixing head for the continuous preparation of prepolymers.
A continuous preparation in which the two reactants are fed via a static mixer into a prepolymer preparation unit has likewise been disclosed (DE-A-2823762).
All reported prepolymers based on mixtures of diphenylmethane diisocyanates with polyphenylpolymethylene polyisocyanates are, compared to mixtures of diphenylmethane diisocyanates with polyphenylpolymethylene polyisocyanates which have not been prepolymerized and have the same viscosity, not suitable for effecting improved curing with reduced crack formation and a fine-celled structure of the foams produced therefrom.
It is an object of the present invention to develop a prepolymer based on mixtures of diphenylmethane diisocyanates with polyphenylpolymethylene polyisocyanates which effects improved curing with reduced crack formation and a fine-celled structure of foams produced therefrom.
We have found, surprisingly, that this object is achieved by reacting an isocyanate mixture consisting predominantly of diphenylmethane diisocyanates and polyphenylpolymethylene polyisocyanates and having a proportion two-ring isomers of not more than 74% by weight with at least 4-functional polyols or a mixture of polyols having a mean functionality of at least 4, where the polyols or polyol mixtures have a hydroxyl number of from 200 to 1650 mg KOH/g and a number average molecular weight of less than 1100 g/mol and the prepolymer containing isocyanate groups has an NCO content of at least 30.0% by weight.
The present invention accordingly provides prepolymers which contain isocyanate groups, have an NCO content of at least 30.0% by weight and can be prepared by reacting an isocyanate mixture consisting predominantly of diphenylmethane diisocyanates and polyphenylpolymethylene polyisocyanates and having a proportion of two-ring isomers of not more than 74% by weight with at least 4-functional polyols or a mixture of polyols having a mean functionality of at least 4, where the polyols or polyol mixtures have a hydroxyl number of from 200 to 1650 mg KOH/g and a number average molecular weight of less than 1100 g/mol.
The present invention also provides a process for preparing these prepolymers containing isocyanate groups, provides for their use for producing polyurethanes and provides a process for producing polyurethanes by reacting at least one novel prepolymer containing isocyanate groups, if desired in admixture with further organic and/or modified organic isocyanates (a), with compounds having at least two reactive hydrogen atoms (b) in the presence of, if desired, blowing agents (c), catalysts (d) and, if desired, further auxiliaries and/or additives (e).
In our studies we have surprisingly found that fine-celled foams having improved curing and low crack formation can be produced using the prepolymers of the present invention. It would have been expected that these prepolymers would, because of their comparatively low content of isocyanate addition products, not give significantly different foam properties than the isocyanate mixtures which have not been prepolymerized.
It was also surprising that no property differences are found when the prepolymers are produced in the isocyanate process stream compared to a conventional preparation in a specific reaction vessel. Owing to the different residence time distributions of batchwise and continuous processes, different prepolymer properties would have been expected.
The use of the process variants of the present invention enables a prepolymer to be produced inexpensively without additional reaction vessels.
To prepare the prepolymers containing isocyanate groups, use is made of at least 4-functional polyols or a mixture of polyols having a mean functionality of at least 4, where the polyols or polyol mixtures have a hydroxyl number of from 200 to 1650 mg KOH/g, preferably from 300 to 1000 mg KOH/g, and a number average molecular weight of less than 1100 g/mol, preferably from 280 to 1000 g/mol.
At least 4-functional polyols are, for example, polyether alcohols based on high-functionality initiator molecules such as pentaerythritol or sugar alcohols, e.g. hexitols, preferably sorbitol, or sugars including polymeric forms such as starch and cellulose. Such initiator molecules are described, for example, in Lehrbuch der organischen Chemie by H. Beyer, 8th Edition 1961, published by S. Hirzel Verlag Leipzig, pages 281 to 314. Preference is given to using adducts of hexitols, in particular sorbitol, and sugars, in particular sucrose, and alkylene oxides, in particular ethylene oxide and propylene oxide.
Additions of polyols, preferably polyether alcohols or polyester alcohols, having a functionality of less than 4 are also possible provided that the conditions specified according to the present invention are adhered to. These polyols are described in more detail further below under the discussion of component (b).
It is particularly advantageous for the polyol used to be a polyetherol, in particular a reaction product of sorbitol, propylene oxide and traces of water having a hydroxyl number of from 200 to 800 mg KOH/g.
The polyols or polyol mixtures are advantageously used in an amount of from 0.1 to 5% by weight, in particular from 0.5 to 3% by weight, based on the total weight of the prepolymer.
To prepare the prepolymers containing isocyanate groups, use is made of isocyanate mixtures consisting predominantly of dimethylmethane diisocyanates and polyphenylpolymethylene polyisocyanates and having a proportion of two-ring isomers of not more than 74% by weight, preferably from 25 to 70% by weight and in particular from 28 to 55% by weight. The isocyanate mixture can further comprise the by-products usual in its preparation, normally in an amount of up to 10% by weight.
Apart from the isocyanate mixtures described, it is also possible to use further organic and/or modified organic polyisocyanates for preparing the prepolymers of the present invention. Suitable polyisocyanates are the aliphatic, cycloaliphatic, araliphatic and preferably aromatic polyfunctional isocyanates known per se, as are described further below under the discussion of component (a). If further organic and/or modified organic polyisocyanates are used, they are preferably added in an amount of up to 50% by weight.
The polyol is preferably metered in such a way that a reaction temperature of from 20 to 100xc2x0 C., preferably from 70 to 90xc2x0 C., is ensured for the formation of the prepolymers containing urethane groups.
In a preferred embodiment, the reaction to form the prepolymer is carried out by metering the polyols or the polyol mixture directly into the process stream and/or the isocyanate container of the isocyanate-producing plant.
The polyol species to be reacted is metered continuously or discontinuously into the isocyanate stream or into the isocyanate container of an isocyanate production plant.
If the preparation of the prepolymer is carried out directly in an isocyanate production plant, any further organic and/or modified organic polyisocyanates used can be metered into the process stream in addition to the polyols or polyol mixtures. However, it is also possible to mix these into the prepolymer after its preparation.
All components which are metered in have to be mixed in well.
In a preferred embodiment of the continuous preparation, the polyols or the polyol mixture are metered, in particular continuously, by a static mixer or a similar suitable mixing device into the isocyanate stream. The metering rate and the metering temperature are selected such that rapid reaction of the polyols metered in can be ensured without the reaction going out of control as a result of hot spots occurring. This type of metering dispenses with the otherwise customary heating processes for prepolymer preparation. It is also possible to introduce the polyol via a static mixer into the storage tank for the isocyanates which the products reach at a relatively high entry temperature. The prepolymer can be fully reacted during the homogenization process.
In a preferred embodiment of the batchwise preparation, the isocyanate or isocyanate mixture is placed in a stirred vessel, if desired heated to from 30 to 80xc2x0 C., and the polyol is added while stirring. To complete the reaction, stirring is continued for from 0.5 to 2 hours at from 30 to 80xc2x0 C. and the prepolymer is dispensed into a storage container or the container for despatch.
The novel prepolymers containing isocyanate groups have an NCO content of at least 30.0% by weight, preferably from 30 to 32% by weight. The viscosity range at 25xc2x0 C. is usually from 100 to 5000 mPas.
The prepolymers/modified polyisocyanates can, if desired, be mixed with one another or with unmodified organic polyisocyanates such as diphenylmethane 2,4xe2x80x2- and/or 4,4xe2x80x2-diisocyanate, crude MDI, tolylene 2,4- and/or 2,6-diisocyanate.
The novel prepolymers containing isocyanate groups are very useful for producing polyurethanes. They are processed to form polyurethane foams in particular, but also to produce non-cellular polyurethanes.
The polyurethanes are produced by reacting, in a known manner, at least one prepolymer containing isocyanate groups and prepared according to the present invention, if desired in admixture with further organic and/or modified organic isocyanates (a), with compounds containing at least two reactive hydrogen atoms (b) in the presence of, if desired, blowing agents (c), catalysts (d) and, if desired, further auxiliaries and/or additives (d).
As regards the individual starting components, the following may be said by way of example:
Suitable organic and/or modified organic polyisocyanates (a) for preparing both the prepolymers of the present invention (isocyanates used concomitantly) and the polyurethanes (isocyanates used concomitantly) are the aliphatic, cycloaliphatic, araliphatic and preferably aromatic polyfunctional isocyanates known per se.
Specific examples are: alkylene diisocyanates having from 4 to 12 carbon atoms in the alkylene radical, e.g. dodecane 1,12-diisocyanate, 2-ethyltetramethylene 1,4-diisocyanate, 2-methylpentamethylene 1,5-diisocyanate, tetramethylene 1,4-diisocyanate and preferably hexamethylene 1,6-diisocyanate, cycloaliphatic diisocyanates such as cyclohexane 1,3- and 1,4-diisocyanate and also any mixtures of these isomers, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (IPDI), hexahydrotolylene 2,4- and 2,6-diisocyanate and also the corresponding isomer mixtures, dicyclohexylmethane 4,4xe2x80x2-, 2,2xe2x80x2- and 2,4xe2x80x2-diisocyanate and also the corresponding isomer mixtures, and preferably aromatic diisocyanates and polyisocyanates such as tolylene 2,4- and 2,6-diisocyanate (-TDI) and the corresponding isomer mixtures, diphenylmethane 4,4xe2x80x2-, 2,4xe2x80x2- and 2,2xe2x80x2-diisocyanate (-MDI) and the corresponding isomer mixtures, mixtures of 4,4xe2x80x2- and 2,2xe2x80x2-MDI, polyphenylpolymethylene polyisocyanates, mixtures of 4,4xe2x80x2-, 2,4xe2x80x2- and 2,2xe2x80x2-MDI and polyphenylpolymethylene polyisocyanates (crude MDI) and mixtures of crude MDI and TDI. The organic diisocyanates and polyisocyanates can be used individually or in the form of any mixtures.
Use is frequently also made of modified polyfunctional isocyanates, i.e. products which are obtained by chemical reaction of organic diisocyanates and/or polyisocyanates. Examples which may be mentioned are diisocyanates and/or polyisocyanates containing ester, urea, biuret, allophanate, carbodiimide, isocyanurate, uretdione and/or urethane groups.
Specific examples are: organic, preferably aromatic, polyisocyanates containing urethane groups, having NCO contents of from 47 to 5% by weight, preferably from 40 to 15% by weight, based on the total weight, and obtained, for example, by reaction with low molecular weight diols, triols, dialkylene glycols, trialkylene glycols or polyoxyalkylene glycols having molecular weights of up to 6000, in particular having molecular weights of up to 1500, modified 4,4xe2x80x2-MDI, modified 4,4xe2x80x2- and 2,4xe2x80x2-MDI mixtures, modified crude MDI or 2,4- or 2,6-TDI, where dialkylene glycols or polyoxyalkylene glycols which can be used individually or as mixtures are, for example: diethylene glycol, dipropylene glycol, polyoxyethylene, polyoxypropylene and polyoxypropylene-polyoxyethylene glycols, triols and/or tetrols.
Other modified polyisocyanates which have been found to be useful are liquid polyisocyanates containing carbodiimide groups and/or isocyanurate rings and having NCO contents of from 47 to 5% by weight, preferably from 40 to 15% by weight, based on the total weight, e.g. based on 4,4xe2x80x2-, 2,4xe2x80x2- and/or 2,2xe2x80x2-MDI and/or 2,4- and/or 2,6-TDI.
The modified polyisocyanates can be mixed with one another or with unmodified organic polyisocyanates such as 2,4xe2x80x2-, 4,4xe2x80x2-MDI, crude MDI, 2,4- and/or 2,6-TDI.
Organic and/or modified organic polyisocyanates (a) which have been found to be particularly useful and are therefore preferably employed are: mixtures of TDI isomers and crude MDI or mixtures of modified organic polyisocyanates containing urethane groups and having an NCO content of from 47 to 5% by weight, in particular those based on TDI isomers, 4,4xe2x80x2-MDI, MDI isomer mixtures or crude MDI and particularly crude MDI having an MDI isomer content of from 30 to 80% by weight, preferably from 30 to 55% by weight.
As compounds containing at least two reactive hydrogen atoms (b), use is advantageously made of those having a functionality of from 2 to 4, preferably from 2 to 3, and a molecular weight of from 300 to 8000, preferably from 300 to 5000. Examples of compounds which have been found to be useful are polyetherpolyamines and/or preferably polyols selected from the group consisting of polyether polyols, polyester polyols, polythioether polyols, polyester amides, hydroxyl-containing polyacetals and hydroxyl-containing aliphatic polycarbonates or mixtures of at least two of the polyols mentioned. Preference is given to using polyester polyols and/or polyether polyols. The hydroxyl number of the polyhydroxyl compounds is generally from 20 to 80 mg KOH/g and preferably from 28 to 56 mg KOH/g.
Suitable polyester polyols can be prepared, for example, from organic dicarboxylic acids having from 2 to 12 carbon atoms, preferably aliphatic dicarboxylic acids having from 4 to 6 carbon atoms, and polyhydric alcohols, preferably diols, having from 2 to 12 carbon atoms, preferably from 2 to 6 carbon atoms. Examples of suitable dicarboxylic acids are: succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, decanedicarboxylic acid, maleic acid, fumaric acid, phthalic acid, isophthalic acid and terephthalic acid. The dicarboxylic acids can be used either individually or in admixture with one another. In place of the free dicarboxylic acids, it is also possible to use the corresponding dicarboxylic acid derivatives, e.g. dicarboxylic esters of alcohols having from 1 to 4 carbon atoms or dicarboxylic anhydrides. Preference is given to using dicarboxylic acid mixtures of succinic, glutaric and adipic acid in weight ratios of, for example, 20-35:35-50:20-32 parts by weight, and in particular adipic acid. Examples of dihydric and polyhydric alcohols, in particular diols, are: ethanediol, diethylene glycol, 1,2- or 1,3-propanediol, dipropylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,10-decanediol, glycerol and trimethylolpropane. Preference is given to using ethanediol, diethylene glycol, 1,4-butanediol, 1,5-pentanediol and 1,6-hexanediol. It is also possible to use polyester polyols derived from lactones, e.g. xcex5-caprolactone, or hydroxycarboxylic acids, e.g. xcfx89-hydroxycaproic acid. To prepare the polyester polyols, the organic, e.g. aromatic and preferably aliphatic, polycarboxylic acids and/or derivatives and polyhydric alcohols can be polycondensed in the absence of catalysts or preferably in the presence of esterification catalysts, advantageously in an atmosphere of inert gas such as nitrogen, carbon monoxide, helium, argon, etc., in the melt at from 150 to 250xc2x0 C., preferably from 180 to 220xc2x0 C., under atmospheric pressure or reduced pressure, to the desired acid number which is advantageously less than 10, preferably less than 2. According to a preferred embodiment, the esterification mixture is polycondensed at the abovementioned temperatures to an acid number of from 80 to 30, preferably from 40 to 30, under atmospheric pressure and subsequently under a pressure of less than 500 mbar, preferably from 50 to 150 mbar. Examples of suitable esterification catalysts are iron, cadmium, cobalt, lead, zinc, antimony, magnesium, titanium and tin catalysts in the form of metals, metal oxides or metal salts. However, the polycondensation can also be carried out in the liquid phase in the presence of diluents and/or entrainers such as benzene, toluene, xylene or chlorobenzene to azeotropically distill off the water of condensation. To prepare the polyester polyols, the organic polycarboxylic acids and/or derivatives and polyhydric alcohols are advantageously polycondensed in a molar ratio of 1:1-1.8, preferably 1:1.05-1.2.
The polyester polyols obtained preferably have a functionality of from 2 to 4, in particular from 2 to 3, and a molecular weight of from 480 to 3000, in particular from 600 to 2000.
However, the relatively high molecular weight compounds containing at least two reactive hydrogen atoms which are used are particularly preferably polyether polyols which can be prepared by known methods, for example from one or more alkylene oxides having from 2 to 4 carbon atoms in the alkylene radical by anionic polymerization using alkali metal hydroxides such as sodium or potassium hydroxide, or alkali metal alkoxides such as sodium methoxide, sodium or potassium ethoxide or potassium isopropoxide, as catalysts with addition of at least one initiator molecule containing from 2 to 4, preferably from 2 to 3, reactive hydrogen atoms in bound form, or by cationic polymerization using Lewis acids such as antimony pentachloride, boron fluoride etherate, etc., or bleaching earth as catalysts. Suitable alkylene oxides are, for example, tetrahydrofuran, 1,3-propylene oxide, 1,2- or 2,3-butylene oxide, styrene oxide and preferably ethylene oxide and 1,2-propylene oxide. The alkylene oxides can be used individually, alternately in succession or as mixtures. Examples of suitable initiator molecules are: water, organic dicarboxylic acids such as succinic acid, adipic acid, phthalic acid and terephthalic acid, aliphatic and aromatic, unalkylated, N-monoalkylated or N,N- and N,Nxe2x80x2-dialkylated diamines having from 1 to 4 carbon atoms in the alkyl radical, e.g. unalkylated, monoalkylated or dialkylated ethylenediamine, diethylenetriamine, triethylenetetramine, 1,3-propylenediamine, 1,3- or 1,4-butylenediamine, 1,2-, 1,3-, 1,4-, 1,5- and 1,6-hexamethylenediamine, phenylenediamine, 2,3-, 2,4- and 2,6-tolylenediamine and 4,4xe2x80x2-, 2,4xe2x80x2- and 2,2xe2x80x2-diaminodiphenylmethane. Further suitable initiator molecules are: alkanolamines such as ethanolamine, N-methylethanolamine and N-ethylethanolamine, dialkanolamines such as diethanolamine, N-methyldiethanolamine and N-ethyldiethanolamine and trialkanolamines such as triethanolamine, and ammonia. Preference is given to using polyhydric, in particular dihydric and/or trihydric alcohols such as ethanediol, 1,2- and 2,3-propanediol, diethylene glycol, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, glycerol, trimethylolpropane and pentaerythritol, while for rigid foam polyetherols relatively high-functionality initiators such as sorbitol and sucrose are predominantly employed.
The polyether polyols, preferably polyoxypropylene polyols and polyoxypropylene-polyoxyethylene polyols, have a functionality of preferably from 2 to 4 and in particular from 2 to 3 and molecular weights of from 300 to 8000, preferably from 300 to 6000 and in particular from 1000 to 5000, and suitable polyoxytetramethylene glycols have a molecule weight of up to about 3500, while for rigid foam polyetherols, molecular weights of from 300 to 1000 are usual.
Further suitable polyether polyols are polymer-modified polyether polyols, preferably graft polyether polyols, in particular those based on styrene and/or acrylonitrile which are prepared by in situ polymerization of acrylonitrile, styrene or preferably mixtures of styrene and acrylonitrile, e.g. in a weight ratio of from 90:10 to 10:90, preferably from 70:30 to 30:70, advantageously in the abovementioned polyether polyols using methods similar to those given in German patents 1111394, 1222669 (U.S. Pat. Nos. 3,304,273, 3,383,351, 3,523,093), 1152536 (GB 1040452) and 1152537 (GB 987618), and also polyether polyol dispersions which comprise as disperse phase, usually in an amount of from 1 to 50% by weight, preferably from 2 to 25% by weight: e.g. polyureas, polyhydrazides, polyurethanes containing bound tertiary amino groups and/or melamine and are described, for example, in EP-B-011752 (U.S. Pat. No. 4,304,708), U.S. Pat. No. 4,374,209 and DE-A-3231497.
Like the polyester polyols, the polyether polyols can be used individually or in the form of mixtures. They can also be mixed with the graft polyether polyols or polyester polyols or with the hydroxy-containing polyesteramides, polyacetals, polycarbonates and/or polyetherpolyamines.
Suitable hydroxyl-containing polyacetals, likewise relatively high molecular weight compounds containing at least two reactive hydrogen atoms, are, for example, the compounds which can be prepared from glycols such as diethylene glycol, triethylene glycol, 4,4xe2x80x2-dihydroxyethoxydiphenyldimethylmethane or hexanediol and formaldehyde. Suitable polyacetals can also be prepared by polymerization of cyclic acetals.
Suitable hydroxyl-containing polycarbonates are those of the type known per se which can be prepared, for example, by reacting diols such as 1,3-propanediol, 1,4-butanediol and/or 1,6-hexanediol, diethylene glycol, triethylene glycol or tetraethylene glycol with diaryl carbonates, e.g. diphenyl carbonate, or phosgene.
The polyester amides as relatively high molecular weight compounds containing at least two reactive hydrogen atoms include, for example, the predominantly linear condensates obtained from polybasic, saturated and/or unsaturated carboxylic acids or their anhydrides and polyfunctional saturated and/or unsaturated aminoalcohols or mixtures of polyfunctional alcohols and aminoalcohols and/or polyamines.
Suitable polyetherpolyamines as relatively high molecular weight compounds containing at least two reactive hydrogen atoms can be prepared from the abovementioned polyetherpolyols by known methods. Examples which may be mentioned are the cyanoalkylation of polyoxyalkylene polyols and subsequent hydrogenation of the nitrile formed (U.S. Pat. No. 3,267,050) or the partial or complete amination of polyoxyalkylene polyols with amines or ammonia in the presence of hydrogen and catalysts (DE 1215373).
Preference is given to using polyester polyols and/or polyether polyols. The hydroxyl number of the polyhydroxyl compounds is generally from 20 to 1590 mg KOH/g for use in flexible foams and preferably from 20 to 200 for rigid foams. However, it is also possible to use mixtures of polyols for producing flexible or rigid foams. In this case, both for rigid and for flexible foams, it is possible to use not only polyols within the specified hydroxyl number range but also those having a hydroxyl number outside the range.
The polyurethanes can be produced with or without use of chain extenders and/or crosslinkers. However, the addition of chain extenders, crosslinkers or, if desired, mixtures thereof can prove to be advantageous for modifying the mechanical properties, e.g. the hardness. Chain extenders and/or crosslinkers used are diols and/or triols having molecular weights of less than 400, preferably from 60 to 300. Suitable chain extenders/crosslinkers are, for example, aliphatic, cycloaliphatic and/or araliphatic diols having from 2 to 14, preferably from 4 to 10, carbon atoms, e.g. ethylene glycol, 1,3-propanediol, 1,10-decanediol, o-, m-, p-dihydroxycyclohexane, diethylene glycol, dipropylene glycol and preferably 1,4-butanediol, 1,6-hexanediol and bis(2-hydroxyethyl)hydroquinone, triols such as 1,2,4-, 1,3,5-trihydroxycyclohexane, glycerol and trimethylolpropane, and low molecular weight hydroxyl-containing polyalkylene oxides based on ethylene oxide and/or 1,2-propylene oxide and the abovementioned diols and/or triols as initiator molecules. The boundary between chain extenders and polymeric polyols is fluid. An adduct of ethanediol and ethylene oxide is, for example, both a low polymer, also known as an oligomer, and a chain extender.
If chain extenders, crosslinkers or mixtures thereof are employed for producing the polyurethanes, in particular foams based on isocyanate, they are advantageously used in an amount of from 0 to 20% by weight, preferably from 1 to 8% by weight, based on the weight of the polyol compound.
Blowing agents (c) used for producing foams based on isocyanate can be the chlorofluorocarbons (CFCs), hydrocarbons consisting of hydrogen, carbon, chlorine and fluorine (HCFCs), hydrocarbons consisting of hydrogen, carbon and fluorine (HFCs) and perfluorinated hydrocarbons generally known from polyurethane chemistry. However, the use of CFCs and HCFCs and also the perfluorinated hydrocarbons is being greatly restricted or completely stopped for ecological reasons. Apart from the HCFCs and HFCs, alternative blowing agents are, in particular, aliphatic and/or cycloaliphatic hydrocarbons, especially pentane and cyclopentane, or acetals such as methylal, and also tetramethylsilane.
These physical blowing agents are usually added to the polyol component of the system. However, they can also be added to the isocyanate component or, as a combination, both to the polyol component and to the isocyanate component. It is also possible to use them together with highly fluorinated and/or perfluorinated hydrocarbons in the form of an emulsion of the polyol component. If emulsifiers are employed, it is usual to use oligomeric acrylates which contain bound polyoxyalkylene and fluoroalkane radicals as side groups and have a fluorine content of from about 5 to 30% by weight. Such products are sufficiently well known from plastics chemistry, e.g. EP-A-351614.
The amount of blowing agent or blowing agent mixture used is from 1 to 25% by weight, preferably from 1 to 15% by weight, in each case based on the polyol component (b).
Furthermore, it is possible and customary to add water as blowing agent to the formative component (b) in an amount of from 0.5 to 15% by weight, preferably from 1 to 5% by weight, based on the formative component (b). The addition of water can be combined with the use of the other blowing agents described.
As catalysts (d) for producing the polyurethanes, use is made, in particular, of compounds which strongly accelerate the reaction of the compounds containing reactive hydrogen atoms, in particular hydroxyl groups, of component (b) with the novel prepolymers containing isocyanate groups and any further organic, modified or unmodified polyisocyanates (a). Suitable catalysts are organic metal compounds, preferably organic tin compounds such as tin(II) salts of organic carboxylic acids, e.g. tin(II) acetate, tin(II) octoate, tin(II) ethylhexanoate and tin(II) laurate, and the dialkyltin(IV) salts of organic carboxylic acids, e.g. dibutyltin diacetate, dibutyltin dilaurate, dibutyltin maleate and dioctyltin diacetate. The organic metal compounds are used alone or preferably in combination with strongly basic amines. Examples which may be mentioned are amidines such as 2,3-dimethyl-3,4,5,6-tetrahydropyrimidine, tertiary amines such as triethylamine, tributylamine, trimethylcyclohexylamine, dimethylbenzylamine, N-methylmorpholine, N-ethylmorpholine, N-cyclohexylmorpholine, N,N,Nxe2x80x2,Nxe2x80x2-tetramethylethylenediamine, N,N,Nxe2x80x2,Nxe2x80x2-tetramethylbutanediamine, N,N,Nxe2x80x2,Nxe2x80x2-tetramethylhexane-1,6-diamine, pentamethyldiethylenetriamine, bis(dimethylaminoethyl) ether, bis(dimethylaminopropyl)urea, dimethylpiperazine, 1,2-dimethylimidazole, 1-azabicyclo[3.3.0]octane and preferably 1,4-diazabicyclo[2.2.2]octane, and alkanolamine compounds such as triethanolamine, triisopropanolamine, N-methyldiethanolamine and N-ethyldiethanolamine and dimethylethanolamine. Further suitable catalysts are: tris(dialkylaminoalkyl)-s-hexahydrotriazines, in particular tris(N,N-dimethylaminopropyl)-s-hexahydrotriazine, tetraalkylammonium hydroxides such as tetramethylammonium hydroxide, alkali metal hydroxides such as sodium hydroxide and alkali alkoxides such as sodium methoxide and potassium isopropoxide, and also alkali metal salts of long-chain fatty acids having from 10 to 20 carbon atoms and possibly lateral OH groups. Preference is given to using from 0.001 to 5% by weight, in particular from 0.05 to 2% by weight, of catalyst or catalyst combination, based on the weight of the formative component (b).
The reaction of the isocyanate groups with one another, e.g. to form isocyanurate groups, is, if necessary, additionally catalyzed in a known manner, e.g. using potassium acetate, potassium octoate, quaternary ammonium salts or triazines or pentamethyldiethylenetriamine.
If desired, further auxiliaries and/or additives (e) can be incorporated into the reaction mixture for producing the polyurethane foams. Examples which may be mentioned are surface-active substances, foam stabilizers, cell regulators, fillers, dyes, pigments, flame retardants, hydrolysis inhibitors, fungistatic and bacteriostatic substances.
Suitable surface-active substances are, for example, compounds which serve to aid the homogenization of the starting materials and may also be suitable for regulating the cell structure of the plastics. Examples which may be mentioned are emulsifiers such as the sodium salts of castor oil sulfates or fatty acids and also amine salts of fatty acids, e.g. diethylamine oleate, diethanolamine stearate, diethanolamine ricinoleate, salts of sulfonic acids, e.g. alkali metal or ammonium salts of dodecylbenzene- or dinaphthylmethanedisulfonic acid and ricinoleic acid, foam stabilizers such as siloxane-oxyalkylene copolymers and other organopolysiloxanes, ethoxylated alkylphenols, ethoxylated fatty alcohols, paraffin oils, castor oil or ricinoleic esters, Turkey red oil and peanut oil, and cell regulators such as paraffins, fatty alcohols and dimethylpolysiloxanes. The above-described oliogmeric acrylates having polyoxyalkylene and fluoroalkane radicals as side groups are also suitable for improving the emulsifying action, the cell structure and/or stabilizing the foam. The surface-active substances are usually employed in amounts of from 0.01 to 5 parts by weight, based on 100 parts by weight of the formative component (b).
For the purposes of the present invention, fillers, in particular reinforcing fillers, are the customary organic and inorganic fillers, reinforcing materials, weighting agents, agents for improving the abrasion behavior in paints, coatings, etc., known per se. Specific examples are: inorganic fillers such as siliceous minerals, for example sheet silicates such as antigorite, serpentine, hornblends, amphiboles, chrysotile and talc, metal oxides such as kaolin, aluminum oxides, titanium oxides and iron oxides, metal salts such as chalk and barite, and inorganic pigments such as cadmium sulfide, zinc sulfide, and also glass, etc. Preference is given to using kaolin (china clay), aluminum silicate and coprecipitates of barium sulfate and aluminum silicate and also natural and synthetic fibrous minerals such as wollastonite, metal fibers and in particular glass fibers of various lengths which may, if desired, be coated with a size. Examples of suitable organic fillers are: carbon, melamine, rosin, cyclopentadienyl resins and graft polymers and also cellulose fibers, polyamide, polyacrylonitrile, polyurethane, polyester fibers based on aromatic and/or aliphatic dicarboxylic esters and, in particular, carbon fibers. The inorganic and organic fillers can be used individually or as mixtures and are advantageously incorporated into the reaction mixture in amounts of from 0.5 to 50% by weight, preferably from 1 to 40% by weight, based on the weight of the components (a) and (b), but the contents of matts, nonwovens and woven fabrics of natural and synthetic fibers may reach values of up to 80% by weight.
Suitable flame retardants are, for example, tricresyl phosphate, tris(2-chloroethyl) phosphate, tris(2-chloropropyl) phosphate, tetrakis(2-chloroethyl) ethylene diphosphate, dimethyl methanephosphonate, diethyl diethanolaminomethylphosphonate and also commercial halogen-containing flame retardant polyols. Apart from the abovementioned halogen-substituted phosphates, it is also possible to use is inorganic or organic flame retardants such as red phosphorus, hydrated aluminum oxide, antimony trioxide, arsenic oxide, ammonium polyphosphate and calcium sulfate, expandable graphite or cyanuric acid derivatives, such as melamine, or mixtures of at least two flame retardants, e.g. ammonium polyphosphates and melamine and, if desired, maize starch or ammonium polyphosphate, melamine and expandable graphite and/or aliphatic or aromatic polyesters, for making the polyisocyanate polyaddition products flame resistant. In general, it has been found to be useful to use from 5 to 50 parts by weight, preferably from 5 to 25 parts by weight, of the flame retardants mentioned per 100 parts by weight of the formative component (b).
Further details regarding the abovementioned other customary auxiliaries and additives may be found in the specialist literature, for example the monograph by J. H. Saunders and K. C. Frisch xe2x80x9cHigh Polymersxe2x80x9d Volume XVI, Polyurethanes, Parts 1 and 2, Interscience Publishers 1962 and 1964, or the Kunststoffhandbuch, Polyurethane, Volume VII, Hanser-Verlag Munich, Vienna, 1st, 2nd and 3rd Editions, 1966, 1983 and 1993.
To produce the polyurethanes, in particular the foams based on isocyanate, the NCO prepolymers of the present invention or their mixtures with other isocyanates (a), compounds containing at least two reactive hydrogen atoms (b) are reacted in such amounts that the equivalence ratio of NCO groups of the prepolymers and polyisocyanates (a) to the sum of the reactive hydrogen atoms of components (b) is 0.80-5:1, preferably 0.90-1.5:1 for polyurethanes and from 1.5:1 to 5:1 for polyurethane/polyisocyanurates.
The polyurethanes, in particular foams based on isocyanates, are advantageously produced by the one-shot method, for example using the high-pressure or low-pressure technique in open or closed molds, for example metal molds. The continuous application of the reaction mixture to suitable conveyor belts for producing foam blocks, sheets or sandwich elements is also customary.
It has been found to be particularly advantageous to employ the two-component process and to combine the formative components (b), (d) and, if desired (c) and (e) as component (A) and to use the NCO prepolymers or mixtures of these prepolymers and further polyisocyanates (a) and, if desired, blowing agents (c) as component (B).
The starting components are mixed at from 15 to 90xc2x0 C., preferably from 20 to 60xc2x0 C. and in particular from 20 to 35xc2x0 C., and introduced into the open mold or under atmospheric or superatmospheric pressure into the close mold or, in the case of a continuous workstation, applied to a belt which accommodates the reaction mixture. Mixing can be carried out mechanically by means of a stirrer, by means of a stirring screw or by high-pressure mixing in a nozzle. The mold temperature is advantageously from 20 to 110xc2x0 C., preferably from 30 to 60xc2x0 C. and in particular from 35 to 55xc2x0 C.
The isocyanate-based foams produced by the process of the present invention have a density of from 10 to 800 kg/m3, preferably from 30 to 500 kg/m3 and in particular from 30 to 70 kg/m3. In addition to the urethane groups, they may also contain isocyanurate, urea, biuret, allophanate, oxazolidone, polyimide, polyamide and carbodiimide groups and adducts of the carbodiimide groups with NCO groups.
The foams produced in this particular way are suitable, for example, as rigid foam for thermal insulation in, for example, refrigerators, long-distance heating systems, heat banks, sandwich elements, insulation boards, etc., and also as flexible foam for upholstery purposes in the furniture and automotive industries and as a constituent in integral foam systems.
The prepolymers of the present invention can, however, also be used for producing non-cellular polyurethanes, e.g. pourable resins, adhesives or sealing compositions.

Prepolymers containing isocyanate groups and a method for the production thereof


A retractable blind assembly including a top section (3,103) with a vertically-extending blind covering material (23,123) extending between a fixed inclined head rail (5,105) and a middle rail (7,107) that is pivotable with respect to the head rail (5,105) about a pivot center that is adjacent to a lowermost end of the head rail, the head rail extending upwardly at an acute angle, the middle rail (7,107) being pivotable between a lower position, in which the middle rail extends horizontally, when the covering material is extended and an upper position, in which the middle rail extends upwardly at an acute angle and is adjacent the head rail, when the covering material is retracted, the covering material in the top section (3,103) having a generally triangular shape with an unattached short apex (13,113) about the pivot center and an opposite, unattached, long side (15,115) when the covering material is extended, a bottom section (9,109) with the covering material extending between the middle rail (7,107) and a horizontally-extending bottom rail (11,111), the bottom rail being movable vertically between the bottom of the blind when the covering material is extended and an upper position, adjacent the middle rail, when the covering material is retracted, at least first and second lift cords (17, 19, 117, 119) for extending and retracting the covering material, the lift cords being connected outside the blind to a cord connector (21,121), wherein the first lift cord (17,117) is routed through the top section (3,103) adjacent its apex and long side (13,15,113,115) and the second lift cord (19,119) is routed such that it passes through the top section between its apex and long side, and wherein when the covering material (23,123) is extended, the total length of the first lift cord (17,117) within the top section (3,103) is equal to the total length of the second lift cord (19,119) within the top section.

1. Field of the Invention
This invention relates to a retractable blind assembly for covering an irregularly shaped window area with an upper triangular portion and a lower rectangular portion. This invention particularly relates to a blind which can be retracted and extended by pulling and releasing a plurality of pull cords.
2. Description of the Relevant Art
It has been a continuing problem to provide retractable cord-operated blinds for covering irregularly shaped windows although solutions had been readily devised for strictly triangular and trapezoidal windows. Polygonal windows of the kind having a generally rectangular outline but with a corner "cut off" have been the most difficult to cover.
Among the attempts to develop suitable retractable cord-operated blinds for such windows with an upper triangular portion and lower rectangular portion are the blinds described in EP 0 532 036, EP 0 674 091 and EP 1 120 534. However, such blinds have not been easy to assemble. Moreover, the configuration and size of the windows that could be provided with such blinds have often been limited.


A rotary machine vane includes a body and an articulated tip pivotally joined thereto. The body is complementary with a slot of a rotor in which it is mountable for radial reciprocation therein. The body includes an arcuate cradle extending axially along a radially outer end thereof. The vane tip includes a pin and an integral plate extending along the pin for facing a casing surrounding the rotor to form a seal therewith. The pin is complementary to the cradle for defining a radial gap therebetween, and is radially outwardly retained by the cradle for rocking movement therein for self-alignment with the casing.

The present invention relates generally to rotary machines, and, more specifically, to a rotary compressor, pump, or engine.
In one type of rotary machine, a rotor is mounted for rotation inside an oblong stator casing. The rotor includes a plurality of circumferentially spaced apart perimeter slots from which extend radially outwardly a respective plurality of vanes. Each of the vanes has a radially outer tip which slides along the casing as the rotor rotates during operation, with the oblong casing causing the vane to reciprocate radially in and out of the rotor slots as the rotor rotates.
The oblong casing defines with the perimeter of the rotor two generally crescent working chambers through which the reciprocating vanes travel. In one chamber, a working fluid such as air is compressed by the rotating vanes. Both working chambers may be similarly configured for air compression and therefore may define a rotary compressor. Or, fuel may be injected into the compressed air and suitably ignited for undergoing expansion in the second chamber for defining an internal combustion rotary engine. In both examples, the vanes either impart energy into the fluid being compressed, or extract energy from the expanding combustion gases, with associated forces being carried through the rotor and cooperating drive shaft.
Rotation of the rotor during operation generates significant centrifugal force on the individual vanes which is reacted by the cooperating casing. The vane tips must therefore be suitably lubricated for decreasing undesirable frictional wear between the vane tips and the casing. In order to reduce the centrifugal forces on the vane tips, the vanes are preferably made as light as possible, yet must also be sufficiently strong for accommodating the reaction forces of compressing the fluid or expanding the gas with a suitable useful life.
An exemplary rotary engine is disclosed in U.S. Pat. No. 5,571,244-Andres which includes lightweight ceramic vanes having an air bearing and seal at the vane tips. Pressurized air is channeled through the vanes and tips from which it is discharged to form a thin air blanket between the vane tips and the cooperating casing. The air blanket provides a low friction air bearing for reacting the centrifugal forces generated in the vanes, and also provides an effective fluid seal for separating the working fluid on both sides of the vane.
The oblong casing disclosed in this patent includes two semi-circular arcuate portions and two flat portions disposed therebetween. The traveling vane tips must therefore transition between the arcuate and flat portions of the casing. At the center of the flat portion and along the arcuate portions of the casing, the vanes travel perpendicular thereto. However, on both off-center sides of the flat portions, the vanes are necessarily non-perpendicular thereto at relatively small tilt angles. The non-perpendicular alignment of the vanes relative to the off-center portions of the flat casing increases the difficulty of establishing an effective air bearing and seal between the vane tips and the casing.
The Andres patent identified above discloses two tip arrangements for providing effective vane tip seals and bearings. However, these arrangements are geometrically fixed in relationship to the vanes, and necessarily change angular orientation relative to the casing at the off-center flat portions thereof. The bearing gap between the vane tips and the casing therefore becomes nonuniform at the off-center flat portions which decreases the effectiveness of the air bearing and seal at the vane tips.
Accordingly, it is desired to provide an improved vane for a rotary machine having a self-aligning, lubricated vane tip.


A vertical orientation liquid crystal display in which orientation control by oblique electric field is performed stably and lowering in light transmission rate of the liquid crystal display is suppressed without increasing the number of manufacturing steps significantly. In the vertical orientation liquid crystal display, a plurality of regions having different inclination orientations of liquid crystal molecule are formed by applying a voltage to each pixel electrode having an aperture or a recessed portion. The liquid crystal display comprises a switching element connected electrically with the pixel electrode, and an auxiliary electrode formed to overlap the aperture or the recessed portion in the pixel electrode wherein the auxiliary electrode is formed of the same film as that of the semiconductor layer in the switching element.

In recent years, on the strength of being thin and having a low power consumption, liquid crystal display devices are broadly used in laptop-type personal computers, mobile phones, information devices such as electronic organizers, camera-integrated VTRs having a liquid crystal monitor, and the like.
As a display mode which can realize a high contrast and a wide viewing angle, a vertical alignment mode utilizing a vertical-alignment type liquid crystal layer is drawing attention. In general, a vertical-alignment type liquid crystal layer is formed by using a liquid crystal material having negative dielectric anisotropy and vertical alignment films.
For example, Patent Document 1 discloses a liquid crystal display device whose viewing angle characteristics are improved by allowing an oblique electric field to be generated near an aperture that is provided in a counter electrode, and around a liquid crystal molecule within the aperture which is in a vertical alignment state, allowing the surrounding liquid crystal molecules to take an inclined orientation.
However, with the construction described in Patent Document 1, it is difficult to form an oblique electric field across the entire region within the pixel. This leads to a problem in that regions in which the liquid crystal molecules have a slow response to voltage occur within the pixel, thus causing an afterimage phenomenon.
In order to solve this problem, Patent Document 2 discloses a technique in which, regularly-arranged apertures are provided in the pixel electrode or the counter electrode to form a plurality of liquid crystal domains exhibiting axisymmetric orientation within the pixel.
Furthermore, Patent Document 3 discloses a technique of providing an auxiliary electrode for stably performing orientation control with an oblique electric field on an active matrix substrate. This auxiliary electrode is provided in a position corresponding to a slit which is formed in a pixel electrode. Moreover, this auxiliary electrode is formed integrally with a storage capacitor electrode for constituting a storage capacitor, and is formed concurrently with and from the same metal film as the gate lines, in a step of forming the gate lines.    [Patent Document 1] Japanese Laid-Open Patent Publication No. 6-301036    [Patent Document 2] Japanese Laid-Open Patent Publication No. 2000-47217    [Patent Document 3] Japanese Laid-Open Patent Publication No. 2006-184334

Liquid crystal display having particular auxiliary electrode


Double-exposure mask structure and photolithography method for performing a photolithography process on a substrate are provided. The substrate has a central region and a margin region. A double-exposure mask structure includes a plurality of parallel and spaced first masks corresponding to the central region, a plurality of parallel and spaced second masks corresponding to the central region, and a plurality of auxiliary masks. The second masks intersect with the first masks to form a plurality of overlapping regions. The auxiliary masks are not in contact with one another, and correspond to the Second masks to assist the overlapping regions neighboring to the auxiliary masks to have sufficient depth of focus for photolithography. With the auxiliary masks, the overlapping regions in the central region and neighboring to the margin region can have preferred photolithography and etching effect.

The miniaturization of a semiconductor has long developed according to Moore's Law, namely, the number of transistors and resistance on one single wafer double each year. Such theorem has quite matched actual situations for the past three decades, and the speed of doubling the number of transistors and resistance on one single wafer currently becomes every 18 months. In principle, the manufacture of a semiconductor is performed by photolithography. As the ever-decreasing size of process, severe complications caused by effect of light diffraction have gradually emerged.
To fit a larger number of transistors into a same-sized wafer, extreme ultraviolet (EUV) and double-exposure techniques are currently developed for reducing a line width and thus the size of transistors. Due to immaturity of the EUV technique, the double-exposure technique accounts as a principal technique for reducing the size of semiconductors. In a double exposure, an exposure position is adjusted by means of displacement after a first exposure and before a second exposure, so as to prevent an incorrect exposure position caused by light diffraction. For instance, the U.S. Patent Publication No. 2008/153299, "Semiconductor Device and Method for Forming a Pattern in the Same with Double Exposure Technology," discloses a double-exposure technology associated with a dynamic random access memory (DRAM) for effectively increasing a yield rate.
FIGS. 1A and 1B show schematic diagrams of a double-exposure mask structure and an etch result. The mask structure includes a substrate 1, a plurality of first masks 2 formed on the substrate 1 and parallel to a first direction, a plurality of second masks 3 formed on the substrate 1 and are perpendicular to the first direction, and a plurality of marginal auxiliary masks 4 formed on the substrate 1 and parallel to the first direction. The first masks 2 and the second masks 3 are overlapped to form a plurality of overlapping points 5. According to whether an etching process is a positive photoresist process or a negative photoresist process, the substrate 1 forms holes or pillars at positions corresponding to the overlapping points 5. FIG. 1B corresponds to a region demarcated by dotted lines in FIG. 1A. Assuming the negative photoresist is used in photolithography, holes 6 are formed at the positions of the overlapping points 5. As the overlapping points 5 at margins are unable to utilize neighboring masks to obtain a sufficient depth of focus (DOF) to form the holes 6, the marginal auxiliary masks 4 are required to be set at edges of the first masks 2 to assist the substrate 1 at the positions of the overlapping points 5 neighboring to the marginal auxiliary masks 4 to form the holes 6.
FIG. 2 shows a curve diagram of a ratio of holes. Referring to FIGS. 2 and 1B, a critical dimension (CD) of H1 corresponding to a marginal hole 7 located at a margin is apparently smaller than critical dimensions of H2 to H5 corresponding to holes 6 at a central region. That is, even with the assistance of the marginal auxiliary masks 4, the marginal holes 7 still suffer from an inadequate critical dimension suitable to perform subsequent processes.

Double-exposure mask structure and photolithography method thereof


Three-terminal solid state Cu-ion actuated analog switching devices are provided. In one aspect, a method of forming a switching device includes: depositing a channel layer on a substrate; forming a source contact and a drain contact on opposite ends of the channel layer; forming a solid electrolyte on the channel layer over the source contact and the drain contact; and depositing a gate onto the solid electrolyte, wherein the source contact, the drain contact, and the gate are three terminals of the switching device. A switching device and a method of operating a switching device are also provided.

Lithium intercalation materials (for example lithium cobalt oxide (LiCoO2)) exhibiting resistivity change as a function of lithium (Li) content have been proposed for neuromorphic and analog computing applications such as synaptic transistors. See, for example, Fuller et al., "Li-ion synaptic transistor for low power analog computing," Advanced Materials 2017, volume 29, issue 4 (published November 2016) (8 pages). However, lithium compounds are both water and air-sensitive. Lithium compounds are also not readily compatible with standard microfabrication procedures.
The high conductivity and manufacturing compatibility of copper (Cu) makes it attractive as a switching material. For instance, Cu has been demonstrated in two-terminal resistive random access memory (ReRAM) devices. See, for example, Arita et al., "Switching operation and degradation of resistive random access memory composed of tungsten oxide and copper investigated using in-situ TEM," Scientific Reports 5:17103 (November 2015) (10 pages). Three-terminal copper-based transistors with liquid electrolyte have also shown reliable switching. See, for example, Xie et al., "Copper atomic-scale transistors," Beilstein J Nanotechnol 8:530-538 (March 2017).
Highly conductive solid state Cu ion electrolytes of the Cu—Rb—I—Cl system such as Cu16Rb4I7Cl13 have been developed. See, for example, Takahashi et al., "Solid-State Ionics: High Copper Ion Conductivity of the System CuCl—Cul—RbCl," Journal of The Electrochemical Society, Vol. 126, No. 10, 1979, pp. 1654-1658 (hereinafter "Takahashi"). Bulk synthesis of these solid state Cu electrolytes has been used for battery applications.
Complementary metal-oxide semiconductor (CMOS)-compatible electronic synapse devices based on Cu/SiO2/W programmable metallization cells have been reported. See, for example, Chen et al., "A CMOS-compatible electronic synapse device based on Cu/SiO2/W programmable metallization cells," Nanotechnology, vol. 27, no. 25, pp. 1-9 (May 2016). However, in two-terminal configurations writing and reading signals are not decoupled, thus leading to reliability issues such as read disturbance.
Thus, there is a need in the art for solid state Cu-based devices capable of reversible multilevel switching.

Three-terminal copper-driven neuromorphic device

International Business Machines Corporation


A method and apparatus to mitigate the severity of the bond-line read-out defect, and more specifically microwave heating to locally cure adhesive bond-line in a single or two stage process comprising heating thermoset adhesive with microwave radiation until the adhesive is fully cured or partially cured. If the adhesive is partially cured, it can be fully cured by being subjected to an additional thermal cycle.

This section provides background information related to the present disclosure which is not necessarily prior art.
High quality class-A surfaces made using composite sheet molding compound (SMC) panels are typically joined to a support structure using polymeric based thermoset adhesives prior to attaching to the vehicle bodies. For example, exterior SMC door panels are often bonded to an internal reinforcing member by a thermoset adhesive. Typically, adhesive-bonding requires a thermal cure cycle in order to facilitate curing and to produce a strong joint. However, the thermal cure cycle intended to cure the adhesive introduces minute surface distortions in the vicinity of the bond-line known as bond-line read-out (BLRO) which deteriorates the visual appeal of the class-A surface. Significant BLRO often results in part rejection and the subsequent time and cost of rework. There remains a need for a cost effective method and apparatus to mitigate the severity of BLRO defects resulting from the curing of adhesives.
In the automotive practices, a polymeric-based thermoset adhesive is cured using a two-stage process. In the first stage, uncured adhesive is applied between the substrates to be joined. External pressure is then applied upon a bonding fixture to maintain dimensional tolerances as it is subjected to the cure temperature for 3-5 minutes. Heat of about 1 kWh at 10 kW is supplied to the adhesive by conduction via the fixture and the substrate until the adhesive is cured to "green strength," which allows one to handle panels joined by adhesive before the adhesive is completely cured. "Green strength" allows joined panels to continue through assembly while the adhesive continues to cure. Since the heat flow to the adhesive from the fixture occurs through the panels, they experience an overall rise in temperature that results in thermal expansion. This, in combination with any differences in the coefficients of linear thermal expansion (CLTEs) between the panels, leads to distortion of the bond-line. At the same time, the adhesive itself marginally distorts due to chemical cure shrinkage. As the adhesive cures partially to green strength, a fraction of these distortions are retained in the joint. The panels joined to green strength are then painted in a paint booth followed by additional heating to cure the paint. The paint "bake" cycle requires another 20-30 minutes of heating of the assembly, resulting in further surface distortion. This process takes a total of about 40 minutes at about 31 kWh per part.
The unwanted side effects of curing adhesives with heat in current practices include the waste of energy spent in the undesired heating of the substrates and surface distortion due to SMC thermal expansion and dimensional changes, or BLRO. There remains a need for a cost-effective method and apparatus to mitigate the severity of BLRO defects resulting from the curing of adhesives.

Method and apparatus to mitigate the bond-line read-out defect in adhesive-bonded composite panels


A mandrel and the blank from which the mandrel is formed is constructed so as to enable shipment in flat form to a manufacturer of material, e.g., fabric, who, in turn, assembles the mandrel and uses such to wind material thereon to form a fabric bolt. The blank is easily and entirely set up by simple folding procedures.

This invention deals with a mandrel or support on which lengths of web-like or strand material such as fabric or dry goods are wound around. The two combined elements, i.e., mandrel and material, form what are commonly referred to as "bolts" which are then shipped to the ultimate end user, e.g., fabric store, discount outlet, wholesale distributor, decorator's or designer's workroom, upholsterer's shop, clothing manufacturer, and the like and or resellers of such material. Usually, the web material is woven cloth, fabric, upholstery material and the like; however, the term "web-like" and "strand-like" to or material is used in a broad sense to include any type of merchandise that can be wound or wrapped around and supported on a mandrel for handling, transshipping and the like. These bolts are usually formed at the supplier's facility, that is, the maker, manufacturer, textile mill, printer, distributor or other processor of the material upon preformed mandrels supplied to them by off-site manufacturers of paper and cardboard products. Generally, the mandrel fabricators are suppliers of other corrugated paperboard products such as boxes, i.e., box makers. Such mandrels are normally formed of paper and cardboard stock materials. Two mandrel forms currently in use include a multi-layer wound paper semi-elliptical hollow body with cardboard end caps glued over the opposed ends thereof and a cardboard flat box-like hollow structure with end closures glued in place.
Such prior art mandrels and the manner of their use necessitates secondary set up operations such as gluing to be performed at the mandrel manufacturer's site and then the completed mandrels shipped to the material supplier in their final ready to use set up and assembled form. Shipping the mandrels in ready to use form creates increased shipping volume per unit resulting in fewer mandrels being able to be shipped in a given volume capacity of a truck or railcar. In some cases, the use of glue in assembling the mandrels also presents an added fire hazard. In addition, a permanently assembled mandrel reduces the ease in which such mandrels can be recycled or otherwise disposed when the mandrel has served its intended purpose.
It, accordingly, would be desirable to provide a mandrel and use system for such that would obviate the above noted prior art deficiencies. These and other advantages over the prior art mandrels and their present manner of use are accomplished by the present invention which provides a mandrel blank from a flat foldable material that is shipped to the material manufacturer in such flat form. The user who then assembles the blank into the usable set up mandrel form without glue by simple and uncomplicated folding procedures. This set up procedure can easily and quickly be accomplished by the manufacturer's employees that wind or wrap the web material upon the mandrel. After the mandrel has served its purpose in the transport and material use by the ultimate end user, e.g., fabric store, discount outlet, wholesale distributor, decorator's or designer's workroom, upholsterer's shop, clothing manufacturer, and the like, the mandrel can then be simply discarded or reformed back to its flat blank form for ease in recycling or shipping back to the web supplier if volumes justify such return shipment.
These advantages are brought about by the aforementioned combination of a flat blank that can be setup and locked in a usable mandrel form without tools and from the suggested use system of such mandrel and blank. Further secondary advantages are accomplished by the particular form and structure of the blank and mandrel of the present invention that enables the easy assembly thereof and provides a resultant low cost mandrel device that can be constructed from well known cut and forming techniques at the mandrel maker's facility.
Other objects, features and advantages of the invention shall become apparent as the description thereof proceeds when considered in connection with the accompanying illustrative drawings.


The disclosed embodiments relate to a vertical tunneling transistor that may include a channel disposed on a substrate. A quantum dot may be disposed so that an axis through the channel and the quantum dot is substantially perpendicular to the substrate. A gate may be disposed so that an axis through the channel, the quantum dot and the gate is substantially perpendicular to the substrate.

1. Field of the Invention
The present invention relates generally to the field of integrated circuit design and, more specifically, to providing a vertical tunneling transistor.
2. Description of the Related Art
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present invention, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Computer systems and other electronic devices typically include a variety of electrically interconnected integrated circuit (IC) packages which perform a variety of functions, including memory and processing functions. An important development in semiconductor technology is a circuit element known as a tunneling transistor. The tunneling transistor is a high speed circuit element in which electrons "tunnel" across a seemingly impenetrable energy barrier based on principles of quantum mechanics. Tunneling transistors may have an increasingly important role in integrated circuit design because they have the potential of allowing development of integrated circuit devices that operate at speeds that are many times faster than typical transistors.
A tunneling transistor may include a small island of conductive material, which may be referred to as a "quantum dot," in addition to a gate, channel, source, and drain. To facilitate room temperature operation, the quantum dot may have dimensions on the order of 1-3 nanometers (nm). Tunneling transistors are typically laid out horizontally so that an axis running through the channel, quantum dot, and gate is parallel to the plane of the substrate on which the tunneling transistor is disposed. Such a horizontal arrangement may facilitate relatively easy alignment of the quantum dot with the channel of the transistor. Such a layout, however, does not lend itself to the benefits of emerging manufacturing technologies such as atomic layer deposition, which may be referred to as "ALD." ALD may be used to create very thin layers of somewhat precise thickness. The ability to closely control layer thickness does not yield significant benefit when producing horizontal tunneling transistors.


This invention provides a fluid mechanism that can arrange a plurality of fluid device units and external fluid devices mounted as a set on the fluid device units effectively and compactly. Each of the fluid device units is arranged with respective side surfaces in a longitudinal direction of the fluid device unit tightly attached, and the external fluid devices are arranged side-by-side external to and outside of the fluid device unit in the width direction. Furthermore, as for an introducing path and a discharging path that connect the external fluid devices and the fluid device unit, the introducing path, which is short, is connected to the discharging path, which is long.

For example, a conventional fluid device unit in the form of a mass flow controller has, as shown in Patent Document 1, a flow rate sensor or a flow rate control valve, and controls a flow rate of a fluid at a set value by an information processing circuit that is separately or integrally provided.
In addition, recently fluid mechanism including mass flow controllers are required to be slim in order to reduce their footprint.
In order to meet this requirement, the present claimed inventor has been developing a mass flow controller whose length in a width direction, i.e., a direction orthogonal to a longitudinal direction viewed from a plan direction, is very short. This mass flow controller comprises one or a plurality of fluid devices between an input port into which a fluid is introduced and an output port from which the fluid discharges, and a direction connecting the input port and the output port viewed from a plan direction is set in the longitudinal direction.
In accordance with this arrangement, even in case of arranging a plurality of fluid paths in parallel, it is possible to configure an extremely compact flow rate control mechanism by arranging a plurality of mass flow controllers in a state of being adjacent each side surface with the longitudinal direction of the fluid device unit substantially parallel each other.
For this kind of the flow rate control mechanism, in addition to the mass flow controllers, auxiliary external fluid devices, such as open/close valves used at a time when the flow rate is to be completely closed or used to halt the mechanism at an abnormal time, are arranged corresponding to each mass flow controllers. Ordinarily these kinds of external fluid devices are arranged in the front and in the rear of the mass flow controller in the longitudinal direction.
In addition, conventionally, in the semiconductor manufacturing process, various component gases are mixed at a predetermined ratio so as to produce a material gas, and the material gas is supplied to inside of a chamber. In order to provide the material gas to the chamber, for example, a gas supply device as shown in Patent Document 2 and Patent Document 3 is used.
Furthermore, since recently a bore of a wafer is enlarged, there is also a case that the material gas is supplied from gas introducing ports arranged at multiple positions in the same chamber. Then a gas supply device further comprising a distributor to divide the mixed material gas into multiple at an arbitrary flow ratio has been developing.

Fluid mechanism, support member constituting fluid mechanism and fluid control system