1. Field of the Invention
This invention relates to reactors for conducting polymerization of monomers, and in particular, bulk polymerization reactors for conducting polymerization of alpha-olefin monomers.
2. Description of Related Art
Formation of polymers from various monomers is a well-known art. As is also well known in the art, the polymerization reactor in which the polymers are formed from the monomers have certain inherent limitations to efficiently form the polymers. A major inherent limitation is the removal of heat from the polymerization reactor created by the chemical reaction between the monomers and the catalyst during formation of the polymers. To overcome this problem, cooling systems have been designed to encase the polymerization reactor in an attempt to remove the heat from the polymerization reactor. Additionally, cooling additives may be included in the polymerization reaction mixture in the polymerization reactor.
Both of these prior attempts, however, have various shortcomings. For example, the use of cooling systems outside the polymerization reactor do not efficiently and effectively remove heat from the polymerization reactor, especially for the center most region of the polymerization reactor. Accordingly, the size of the polymerization reactor must be small and limited amounts of polymer may be formed in each reactor batch. Additionally, with respect to the addition of cooling additives to the polymerization reactants, these cooling additives can have an adverse effect on the quality of the polymer as well as increasing the cost associated with forming the polymer.
In other prior attempts, as discussed in U.S. Pat. Nos. 5,449,732, entitled Solvent Free Oil Soluble Drag Reducing Polymer Suspension, 5,504,131, entitled Solvent Free Oil Soluble Drag Reducing Polymer Suspension, and 5,504,132, entitled Solvent Free Oil Soluble Drag Reducing Polymer Suspension, the polymerization reactor is a crystalline, hydrocarbon-insoluble organic polymer reaction enclosure capable of substantially preventing passage of oxygen and water, i.e., plastic bags. Use of these plastic bags permits the polymerization reaction to be carried out without a cooling system or addition of cooling additives. However, because the plastic bags are not provided with any assistance in the removal of heat from the polymerization reaction, only small amounts of polymer reactants, e.g., monomer and catalyst, can be included in each plastic bag. As such, only small amounts of polymer can be formed in each of this type of polymerization reactor. Further, the plastic bags can not be easily separated from the polymer, and thus, are not re-useable.
Accordingly, prior to the development of the present invention, there has been no polymerization reactor or process for forming polymers, which: effectively remove heat away from the polymerization reactor; permit the formation of a large amount of polymer in each polymerization reactor; do not require the addition of cooling additives; and permit the use of a re-useable polymerization reactor. Therefore, the art has sought a polymerization reactor and a process for forming polymers, which: effectively remove heat away from the polymerization reactor; permit the formation of a large amount of polymer in each polymerization reactor; do not require the addition of cooling additives; and permit the use of a re-useable polymerization reactor.
In accordance with the invention, the foregoing advantages have been achieved through the present polymerization method for polymerization of olefins comprising: adapting a reservoir having at least three side wall surfaces and a bottom wall surface thereby forming a reservoir cavity; adapting at least one heat exchanger plate in fluid communication with a coolant source; and adapting a lid having a top wall surface and an inner wall surface, wherein the at least one heat exchanger plate is disposed along inner wall surface.
A further feature of the polymerization reactor is that the polymerization reactor may comprise four side wall surfaces. Another feature of the polymerization reactor is that each of the four side wall surfaces may have a square shape having a length and a height. An additional feature of the polymerization reactor is that two of the four side wall surfaces may have a length of at least two feet and a height of at least two feet and the other two of the four side wall surfaces may have a length of at least three feet and a height of at least two feet. Still another feature of the polymerization reactor is that the lid may be rectangularly shaped having a length and a width, the length being at least three feet and the width being at least two feet. A further feature of the polymerization reactor is that the lid may include at least two heat exchanger plates. Another feature of the polymerization reactor is that each of the at least two heat exchanger plates may be disposed at a distance of at least three inches from each other. An additional feature of the polymerization reactor is that the polymerization reactor may further comprise at least one coolant inlet manifold in fluid communication with the coolant source and at least one coolant outlet manifold in fluid communication with the coolant source. Still another feature of the polymerization reactor is that the polymerization reactor may further comprise at least one coolant inlet conduit in fluid communication with the at least one coolant inlet manifold and in fluid communication with each of the at least one heat exchanger plates, and at least one coolant outlet conduit in fluid communication with the at least one coolant outlet manifold and in fluid communication with each of the at least one heat exchanger plates. A further feature of the polymerization reactor is that the lid may include a plate hanger assembly disposed along the inner wall surface for attaching each of the at least one heat exchanger plates to the inner wall surface of the lid. Another feature of the polymerization reactor is that each of the at least one heat exchanger plates may be in fluid communication with a coolant inlet conduit and a coolant outlet conduit. An additional feature of the polymerization reactor is that each of the coolant inlet conduits may be in fluid communication with a coolant inlet manifold and each of the coolant outlet conduits may be in fluid communication with a coolant outlet manifold. Still another feature of the polymerization reactor is that the coolant inlet manifold and the coolant outlet manifold may be in fluid communication with the coolant source. A further feature of the polymerization reactor is that the reservoir may include four walls having a length, the length being at least 4 feet, and a width, the width being at least 2 feet. Another feature of the polymerization reactor is that the inner wall surface of the lid may include at least 6 heat exchanger plates. An additional feature of the polymerization reactor is that each of the at least one heat exchanger plate may include a removable film.
In accordance with the invention, the foregoing advantages have also been achieved through the present polymerization reactor for polymerization of olefins comprising: a reservoir having at least three side wall surfaces and a bottom wall surface thereby forming a reservoir cavity; a heat exchanger, the heat exchanger having a heat exchanger assembly, coolant inlet manifold in fluid communication with a coolant source, at least one coolant inlet conduit in fluid communication with at least one heat exchanger plate, at least one coolant outlet conduit in fluid communication with each of the at least one heat exchanger plate and in fluid communication with a coolant outlet manifold, the coolant outlet manifold in fluid communication with the coolant source; and a lid having a top wall surface and an inner wall surface, wherein the at least one heat exchanger plate is disposed along inner wall surface.
A further feature of the polymerization reactor is that the polymerization reactor comprises four side wall surfaces, two of the four side wall surfaces having a length of at least two feet and a height of at least two feet, the other two of the four side wall surfaces having a length of at least three feet and a height of at least two feet, and the lid is rectangularly shaped having a length and a width, the length being at least three feet and the width being at least two feet.
In accordance with the invention, the foregoing advantages have also been achieved through the present method of polymerization comprising the steps of: combining at least one monomer and at least one catalyst in a reservoir to form a polymerization reaction mixture, the reservoir having at least three side walls and a bottom wall thereby forming a reservoir cavity; inserting at least one heat exchanger plate having an exchanger cavity in fluid communication with a coolant source into the reservoir cavity thereby contacting the polymerization reaction mixture; and removing the at least one heat exchanger plate from the reaction mixture after sufficient time has passed to permit a majority of the at least one monomer to form a polymer.
A further feature of the method of polymerization is that the method may further comprise the step of disposing a removable film on each of the at least one heat exchanger plate prior to inserting the at least one heat exchanger plate into the reservoir cavity.
The polymerization reactor and process for forming polymers have the advantages of: effectively removing heat away from the polymerization reactor; permitting the formation of a large amount of polymer in each polymerization reactor; not requiring the addition of cooling additives; and permitting the use of a re-useable polymerization reactor.
While the invention will be described in connection with the preferred embodiment, it will be understood that it is not intended to limit the invention to that embodiment. On the contrary, it is intended to cover all alternatives, modifications, and equivalents, as may be included within the spirit and scope of the invention as defined by the appended claims.
Broadly, the polymerization reactor of the present invention includes a reservoir and a lid having a heat exchanger. When the lid is placed on the reservoir, the head exchanger is disposed within the reservoir thereby cooling, i.e., removing heat from, the contents of the reservoir.
Referring now to
Reservoir 80 preferably includes at least one skid 88. As shown in
As shown in
Reservoir 80 may be formed out of any material known to persons of ordinary skill in the art. Preferably, reservoir 80 is formed out of stainless steel.
Referring now to
Heat exchanger 60 preferably includes plate hanger assembly 61, coolant inlet manifold 62, coolant outlet manifold 63, at least one coolant inlet conduit 64, at least one coolant outlet conduit 65, and at least one heat exchanger plate 66 having exchanger cavity 69. Hanger assembly 61 preferably includes bracket 59 to permit attachment of each heat exchanger 66 to lid 70.
Coolant inlet manifold 62 is in fluid communication with at least one coolant inlet conduit 64 which is in fluid communication with heat exchanger plate 66. Likewise, coolant outlet manifold 63 is in fluid communication with at least one coolant outlet conduit 65 which is in fluid communication with heat exchanger plate 66. In one specific embodiment, having one heat exchanger plate 66, one of each of coolant inlet conduit 64 and coolant outlet conduit 65 is in fluid communication with coolant input manifold 62 and coolant outlet manifold 63, respectively. In other embodiments having more than one heat changer plate 66, as shown in
As discussed above, coolant inlet manifold 62 and coolant output manifold 63 are in fluid communication with coolant source. Acceptable coolant sources include, but are not limited to, refrigeration units readily known to persons of ordinary skill in the art employing water, water-glycol mixtures, water-alcohol mixtures, dissolved mineral salts, e.g., sodium chloride and calcium chloride, and ammonium as coolants. In this arrangement, coolant may be circulated from the coolant source, through a conduit, e.g., pipe or flexible hose (not shown), into coolant inlet manifold 61. Coolant is then permitted to enter coolant inlet conduit 64 and into exchanger cavity 69 of each heat exchanger plate 66.
Coolant then is permitted to exit each exchanger cavity 69 of each heat exchanger plate 66 through coolant outlet conduit 65 and into coolant outlet manifold 63. Coolant is then transported back to coolant source from coolant outlet manifold 65 through a conduit, e.g., pipe or flexible hose (not shown) to be recharged, i.e., cooled, and circulated back through heat exchanger 60.
Referring now to
In a preferred embodiment, each heat exchanger plate 66 includes a removable film, e.g., plastic sheath, to prevent polymer formed in reservoir 80 during polymerization from adhering to each heat exchanger plate 66. Suitable removable films include plastic sheeting, plastic sheath, a spray-on non-stick substance that is incapable of being polymerized by the polymerization reaction mixture, for example, because the spray-on non-stick substance has a melting point higher than the temperature of the polymerization reaction mixture.
The number of heat exchanger plates 66 present in each embodiment of polymerization reactor 40 is determined by the size of reservoir 80. In the specific embodiment illustrated in
The polymerization reactors 40 of the present invention may be used to polymerize monomers into polymers, and in particular, alpha olefin monomers into polyalphaolefins. As mentioned above, numerous polymerization methods, reactants, i.e., monomers, catalysts, cocatalysts, are known to persons of ordinary skill in the art. Additionally, bulk polymerization methods are known to persons of ordinary skill in the art. However, none of these known polymerization methods have been conducted in the polymerization reactors 80 discussed above.
In one specific embodiment of the present method for polymerization, at least one monomer and at least one catalyst are combined to form a polymerization reaction mixture in reservoir 80. Lid 80 having at least one heat exchanger plate 66 is then disposed on top of reservoir 80 to protect the polymerization reaction mixture from the environment. During placement of lid 70, each of the at least one heat exchanger plates 66 are inserted into reservoir 80, and thus, the polymerization reaction mixture. Preferably, lid 70 is lowered in the direction of arrow 99 during insertion of each of the at least one heat exchanger plates 66 into the polymerization reaction mixture. Coolant is then permitted to passing from the coolant source and into, and then out of, each exchanger cavity 69 of each of the at least one heat exchanger plates 66. During circulation of coolant through each heat exchanger plate 66, the polymerization reaction mixture is cooled. Each heat exchanger plate 66 is permitted to contact the polymerization reaction mixture for a length of time necessary for a majority of the monomers to be polymerized into polymer. Lid 70 may then be moved in the direction of arrow 98 for removal of each of the at least one heat exchanger plates 66 from the polymerization reaction mixture.
It is to be understood that the invention is not limited to the exact details of construction, operation, exact materials, or embodiments shown and described, as obvious modifications and equivalents will be apparent to one skilled in the art. For example, each of the heat exchanger plates may include more than one coolant inlet conduit or more than one coolant outlet conduit. The dimensions and shapes of the polymerization reactors can be easily determined by a person of ordinary skill in the art. Moreover, additional diagnostic gauges may be included as part of the polymerization reactor, e.g., for monitoring temperature during the polymerization reaction. Additionally, the shape of the heat exchanger plates may be any shaped desired or necessary due to the shape of the reservoir, e.g., circularly-shaped, rectangularly-shaped, triangularly-shaped, trapezoidally-shaped, etc. Accordingly, the invention is therefore to be limited only by the scope of the appended claims.
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/297,931, filed Jun. 13, 2001.
| Number | Name | Date | Kind |
|---|---|---|---|
| 3140277 | Coover et al. | Jul 1964 | A |
| 3143537 | Edwards et al. | Aug 1964 | A |
| 3146224 | Coover et al. | Aug 1964 | A |
| 3216935 | Morway et al. | Nov 1965 | A |
| 3230208 | Coover et al. | Jan 1966 | A |
| 3257332 | Briel et al. | Jun 1966 | A |
| 3284427 | Coover et al. | Nov 1966 | A |
| 3299024 | D'Alelio | Jan 1967 | A |
| 3309346 | Coover et al. | Mar 1967 | A |
| 3309347 | Coover et al. | Mar 1967 | A |
| 3401157 | Coover | Sep 1968 | A |
| 3489736 | Fujimaki et al. | Jan 1970 | A |
| 3496157 | Cernia et al. | Feb 1970 | A |
| 3496158 | Fisher et al. | Feb 1970 | A |
| 3506616 | Wolf | Apr 1970 | A |
| 3507845 | Hornbaker | Apr 1970 | A |
| 3560593 | Hsieh | Feb 1971 | A |
| 3586657 | Casey | Jun 1971 | A |
| 3607692 | Sanner et al. | Sep 1971 | A |
| 3639267 | Vandenberg | Feb 1972 | A |
| 3644223 | Hashimoto et al. | Feb 1972 | A |
| 3669940 | Desgurse et al. | Jun 1972 | A |
| 3674765 | Carter et al. | Jul 1972 | A |
| 3684778 | Hammer | Aug 1972 | A |
| 3691111 | Takaoka et al. | Sep 1972 | A |
| 3700707 | Durst et al. | Oct 1972 | A |
| 3711576 | Hwa | Jan 1973 | A |
| 3725378 | Chamberlin | Apr 1973 | A |
| 3755268 | Fritze | Aug 1973 | A |
| 3773470 | Rouzier | Nov 1973 | A |
| 3819559 | Barabas | Jun 1974 | A |
| 3842904 | Gardenier | Oct 1974 | A |
| 3867361 | Calderon et al. | Feb 1975 | A |
| 3879495 | Fujii et al. | Apr 1975 | A |
| 3884857 | Ballard et al. | May 1975 | A |
| 3903019 | Hargis et al. | Sep 1975 | A |
| 3903201 | Childers et al. | Sep 1975 | A |
| 3925300 | Roberts et al. | Dec 1975 | A |
| 3926928 | Karayannis et al. | Dec 1975 | A |
| 3932369 | Lundberg et al. | Jan 1976 | A |
| 3932371 | Powers | Jan 1976 | A |
| 3932373 | Calderon | Jan 1976 | A |
| 3943116 | Bell | Mar 1976 | A |
| 3953398 | Kline | Apr 1976 | A |
| 3957912 | Cincera | May 1976 | A |
| 3960824 | Hicks | Jun 1976 | A |
| 3960987 | Kelley et al. | Jun 1976 | A |
| 3962197 | Khanna | Jun 1976 | A |
| 3963685 | Abrahams | Jun 1976 | A |
| 3970612 | Hooker | Jul 1976 | A |
| 3971767 | Setterquist | Jul 1976 | A |
| 3975331 | Spiewak | Aug 1976 | A |
| 3978032 | Manner | Aug 1976 | A |
| 3985720 | Manner | Oct 1976 | A |
| 3989768 | Milkovich et al. | Nov 1976 | A |
| 3991262 | Lal et al. | Nov 1976 | A |
| 4002815 | Minchak | Jan 1977 | A |
| 4008175 | Barter | Feb 1977 | A |
| 4011388 | Murphy et al. | Mar 1977 | A |
| 4012462 | Chaudhary | Mar 1977 | A |
| 4022954 | Kurosawa et al. | May 1977 | A |
| 4031300 | Thaler et al. | Jun 1977 | A |
| 4038471 | Castner | Jul 1977 | A |
| 4039722 | Dickie et al. | Aug 1977 | A |
| 4041208 | Seeger et al. | Aug 1977 | A |
| 4057672 | Creekmore et al. | Nov 1977 | A |
| 4060677 | Walker | Nov 1977 | A |
| 4065532 | Wild et al. | Dec 1977 | A |
| 4069364 | Dickie et al. | Jan 1978 | A |
| 4072790 | Creekmore et al. | Feb 1978 | A |
| 4074040 | Gropper et al. | Feb 1978 | A |
| 4081592 | Giddings et al. | Mar 1978 | A |
| 4098980 | Markle et al. | Jul 1978 | A |
| 4100227 | Bredeweg et al. | Jul 1978 | A |
| 4100228 | Dennis et al. | Jul 1978 | A |
| 4103070 | Ammons | Jul 1978 | A |
| 4128604 | Katchman et al. | Dec 1978 | A |
| 4129704 | Sanchez | Dec 1978 | A |
| 4137216 | Lemper et al. | Jan 1979 | A |
| 4143100 | Schulz et al. | Mar 1979 | A |
| 4148766 | McClain | Apr 1979 | A |
| 4150003 | McClain et al. | Apr 1979 | A |
| 4151133 | McClain | Apr 1979 | A |
| 4155899 | Lemper et al. | May 1979 | A |
| 4160850 | Ammons | Jul 1979 | A |
| 4168255 | Lewis et al. | Sep 1979 | A |
| 4170613 | Marubashi | Oct 1979 | A |
| 4172188 | Balle et al. | Oct 1979 | A |
| 4178263 | Priddy et al. | Dec 1979 | A |
| 4187210 | Howard | Feb 1980 | A |
| 4190718 | Lorenz et al. | Feb 1980 | A |
| 4195137 | Walker | Mar 1980 | A |
| 4203880 | Stoloff et al. | May 1980 | A |
| 4205141 | Liebig et al. | May 1980 | A |
| 4212719 | Osada et al. | Jul 1980 | A |
| 4215022 | Buckley et al. | Jul 1980 | A |
| 4223114 | Suling et al. | Sep 1980 | A |
| 4225567 | Halasa et al. | Sep 1980 | A |
| 4226846 | Schulz et al. | Oct 1980 | A |
| 4226956 | Schulz et al. | Oct 1980 | A |
| 4229547 | Cohen et al. | Oct 1980 | A |
| 4230772 | Swift et al. | Oct 1980 | A |
| 4233424 | Suling et al. | Nov 1980 | A |
| 4239879 | Fabris et al. | Dec 1980 | A |
| 4241197 | Steffen et al. | Dec 1980 | A |
| 4256636 | Roos et al. | Mar 1981 | A |
| 4259458 | Robeson | Mar 1981 | A |
| 4259465 | Barabas | Mar 1981 | A |
| 4260712 | Aggarwal et al. | Apr 1981 | A |
| 4263418 | Steffen et al. | Apr 1981 | A |
| 4283511 | Ueno et al. | Aug 1981 | A |
| 4283512 | Matsushima et al. | Aug 1981 | A |
| 4286078 | Botsch et al. | Aug 1981 | A |
| 4289678 | Calder et al. | Sep 1981 | A |
| 4289825 | Kolycheck et al. | Sep 1981 | A |
| 4337189 | Bromley et al. | Jun 1982 | A |
| 4358572 | Mack et al. | Nov 1982 | A |
| 4376847 | Ishida et al. | Mar 1983 | A |
| 4380617 | Minchak et al. | Apr 1983 | A |
| 4410659 | Lee et al. | Oct 1983 | A |
| 4411804 | DeVries et al. | Oct 1983 | A |
| 4419465 | Backhouse et al. | Dec 1983 | A |
| 4419488 | Fukumoto et al. | Dec 1983 | A |
| 4435553 | Throckmorton et al. | Mar 1984 | A |
| 4451618 | Okamoto | May 1984 | A |
| 4451633 | Brownscombe et al. | May 1984 | A |
| 4452960 | Throckmorton | Jun 1984 | A |
| 4461868 | Lindner et al. | Jul 1984 | A |
| 4463137 | Bodolus et al. | Jul 1984 | A |
| 4464495 | Brown | Aug 1984 | A |
| 4477622 | Sanderson et al. | Oct 1984 | A |
| 4482608 | Isbrandt et al. | Nov 1984 | A |
| 4485211 | Okamoto | Nov 1984 | A |
| 4503204 | Bingham et al. | Mar 1985 | A |
| 4507342 | Kielbania, Jr. | Mar 1985 | A |
| 4507414 | McRowe | Mar 1985 | A |
| 4508606 | Andrade et al. | Apr 1985 | A |
| 4508640 | Kanda et al. | Apr 1985 | A |
| 4520183 | Subramanian | May 1985 | A |
| 4536545 | Olener et al. | Aug 1985 | A |
| 4537933 | Walker et al. | Aug 1985 | A |
| 4547323 | Carlson | Oct 1985 | A |
| 4547428 | Bekker et al. | Oct 1985 | A |
| 4562229 | Walker et al. | Dec 1985 | A |
| 4587297 | Walker et al. | May 1986 | A |
| 4588776 | Bekker et al. | May 1986 | A |
| 4605704 | Eastman et al. | Aug 1986 | A |
| 4605721 | Hawkins et al. | Aug 1986 | A |
| RE32261 | Hirota et al. | Oct 1986 | E |
| 4619983 | Yamabe et al. | Oct 1986 | A |
| 4629743 | Hong | Dec 1986 | A |
| 4636458 | Wenzel et al. | Jan 1987 | A |
| 4663405 | Throckmorton | May 1987 | A |
| 4692498 | Bodolus et al. | Sep 1987 | A |
| 4695608 | Engler et al. | Sep 1987 | A |
| 4701510 | Minchak et al. | Oct 1987 | A |
| 4713444 | Matsuyama et al. | Dec 1987 | A |
| 4716205 | Klabunde | Dec 1987 | A |
| 4728545 | Kurauchi et al. | Mar 1988 | A |
| 4728571 | Clemens et al. | Mar 1988 | A |
| 4737410 | Kantner | Apr 1988 | A |
| 4749757 | Schram et al. | Jun 1988 | A |
| 273090 | Kamath | Jul 1988 | A |
| 4758608 | Collins et al. | Jul 1988 | A |
| 4759991 | Kanno et al. | Jul 1988 | A |
| 4763133 | Takemura et al. | Aug 1988 | A |
| 4775702 | Cozens | Oct 1988 | A |
| 4777230 | Kamath | Oct 1988 | A |
| 4788258 | Collins et al. | Nov 1988 | A |
| 4791181 | Pickering et al. | Dec 1988 | A |
| 4806581 | Walker | Feb 1989 | A |
| 4816107 | Collins et al. | Mar 1989 | A |
| 4831096 | MacLeay | May 1989 | A |
| 4833183 | Vandenberg | May 1989 | A |
| 4833223 | Myers | May 1989 | A |
| 4835236 | Grossoleil et al. | May 1989 | A |
| 4839456 | Kent | Jun 1989 | A |
| 4843185 | Ware et al. | Jun 1989 | A |
| 4845165 | Halasa et al. | Jul 1989 | A |
| 4847332 | Yu | Jul 1989 | A |
| 4849572 | Chen et al. | Jul 1989 | A |
| 4877860 | Collins et al. | Oct 1989 | A |
| 348963 | Lukas et al. | Jan 1990 | A |
| 4899005 | Lane et al. | Feb 1990 | A |
| 4902772 | Carter et al. | Feb 1990 | A |
| 358182 | Greenlee et al. | Mar 1990 | A |
| 4906797 | Lane et al. | Mar 1990 | A |
| 4913964 | Fujii et al. | Apr 1990 | A |
| 4920182 | Manser et al. | Apr 1990 | A |
| 4925903 | Myers | May 1990 | A |
| 4937312 | Collins et al. | Jun 1990 | A |
| 4954400 | Collins et al. | Sep 1990 | A |
| 4959408 | Grant | Sep 1990 | A |
| 405786 | Ballard et al. | Jan 1991 | A |
| 4981696 | Loomis et al. | Jan 1991 | A |
| 4981827 | Ballard et al. | Jan 1991 | A |
| 4988597 | Spiewak et al. | Jan 1991 | A |
| 413464 | Ballard et al. | Feb 1991 | A |
| 413465 | Ballard et al. | Feb 1991 | A |
| 5001244 | Wellborn, Jr. | Mar 1991 | A |
| 5004820 | Buchwald et al. | Apr 1991 | A |
| 5006500 | Chang | Apr 1991 | A |
| 5026798 | Canich | Jun 1991 | A |
| 5035867 | Dang Vu et al. | Jul 1991 | A |
| 5036148 | Chanzy et al. | Jul 1991 | A |
| 5037890 | Yokoyama et al. | Aug 1991 | A |
| 5039717 | Kawakami et al. | Aug 1991 | A |
| 5045607 | Wissbrun et al. | Sep 1991 | A |
| 5076659 | Bekiarian et al. | Dec 1991 | A |
| 5084368 | Hirayama et al. | Jan 1992 | A |
| 5086024 | Crapo et al. | Feb 1992 | A |
| 5086025 | Chang | Feb 1992 | A |
| 5086134 | Antberg et al. | Feb 1992 | A |
| 5089295 | McNeil | Feb 1992 | A |
| 5089576 | Saya et al. | Feb 1992 | A |
| 5102401 | Lambert et al. | Apr 1992 | A |
| 5124402 | Laughner et al. | Jun 1992 | A |
| 5126404 | Eckel et al. | Jun 1992 | A |
| 5130369 | Hughes et al. | Jul 1992 | A |
| 5130374 | Cozens et al. | Jul 1992 | A |
| 5145374 | Stansbury | Sep 1992 | A |
| 5147955 | Lindner et al. | Sep 1992 | A |
| 5149757 | Kantor et al. | Sep 1992 | A |
| 5156913 | Collins et al. | Oct 1992 | A |
| 5159003 | Baghail | Oct 1992 | A |
| 5162445 | Powers et al. | Nov 1992 | A |
| 5164282 | Mahabadi | Nov 1992 | A |
| 5183867 | Wellborn, Jr. | Feb 1993 | A |
| 5185405 | Nishida | Feb 1993 | A |
| 5194365 | Goodin et al. | Mar 1993 | A |
| 5194471 | Hartitz | Mar 1993 | A |
| 5194619 | Reuschling et al. | Mar 1993 | A |
| 5196489 | Ballard et al. | Mar 1993 | A |
| 5198401 | Turner et al. | Mar 1993 | A |
| 5200468 | Pickton | Apr 1993 | A |
| 5200537 | Lee et al. | Apr 1993 | A |
| 5202398 | Antberg et al. | Apr 1993 | A |
| 5204380 | Seyferth et al. | Apr 1993 | A |
| 5204429 | Kaminsky et al. | Apr 1993 | A |
| 5208304 | Waymouth | May 1993 | A |
| 5208305 | Grootaert | May 1993 | A |
| 5208357 | Mintz | May 1993 | A |
| 5209971 | Bubu et al. | May 1993 | A |
| 5210130 | Howard | May 1993 | A |
| 5210338 | Samsel | May 1993 | A |
| 5214173 | Jordan et al. | May 1993 | A |
| 5216095 | Dolle et al. | Jun 1993 | A |
| 5218072 | Kumar et al. | Jun 1993 | A |
| 5219962 | Johnson et al. | Jun 1993 | A |
| 5219964 | Albano et al. | Jun 1993 | A |
| 5223467 | Razavi | Jun 1993 | A |
| 5223468 | Razavi | Jun 1993 | A |
| 5225491 | Yu | Jul 1993 | A |
| 5225500 | Elder et al. | Jul 1993 | A |
| 5232993 | Winter et al. | Aug 1993 | A |
| 5238892 | Chang | Aug 1993 | A |
| 5238968 | Morita et al. | Aug 1993 | A |
| 5239022 | Winter et al. | Aug 1993 | A |
| 5240894 | Burkhardt et al. | Aug 1993 | A |
| 5240972 | Kumar et al. | Aug 1993 | A |
| 5241025 | Hlatky et al. | Aug 1993 | A |
| 5243001 | Winter et al. | Sep 1993 | A |
| 5243002 | Razavi | Sep 1993 | A |
| 5252384 | Bothe et al. | Oct 1993 | A |
| 5252677 | Tomita et al. | Oct 1993 | A |
| 5254394 | Bothe et al. | Oct 1993 | A |
| 5256745 | Grootaert | Oct 1993 | A |
| 5258475 | Kissin | Nov 1993 | A |
| 5260389 | Resconi et al. | Nov 1993 | A |
| 5262498 | Antberg et al. | Nov 1993 | A |
| 5266533 | Leung et al. | Nov 1993 | A |
| 5272238 | Garnier et al. | Dec 1993 | A |
| 5276220 | Samsel et al. | Jan 1994 | A |
| 5278264 | Spaleck et al. | Jan 1994 | A |
| 5278265 | Razavi | Jan 1994 | A |
| 5279999 | DeBoer et al. | Jan 1994 | A |
| 5280074 | Schreck et al. | Jan 1994 | A |
| 5281679 | Jejelowo et al. | Jan 1994 | A |
| 5283300 | Haspeslagh et al. | Feb 1994 | A |
| 5292838 | Razavi | Mar 1994 | A |
| 5296237 | Muller et al. | Mar 1994 | A |
| 5296434 | Karl et al. | Mar 1994 | A |
| 5302733 | Diefenbach et al. | Apr 1994 | A |
| 5304523 | Razavi | Apr 1994 | A |
| 5304614 | Winter et al. | Apr 1994 | A |
| 5304622 | Ikai et al. | Apr 1994 | A |
| 5308811 | Suga et al. | May 1994 | A |
| 5308815 | Sangokoya | May 1994 | A |
| 5308817 | Reddy et al. | May 1994 | A |
| 5314957 | Asanuma et al. | May 1994 | A |
| 5314973 | Welborn, Jr. | May 1994 | A |
| 5322902 | Schreck et al. | Jun 1994 | A |
| 5324801 | Brekner et al. | Jun 1994 | A |
| 5326835 | Ahvenainen et al. | Jul 1994 | A |
| 5328969 | Winter et al. | Jul 1994 | A |
| 5329031 | Miyake et al. | Jul 1994 | A |
| 5330948 | Marks et al. | Jul 1994 | A |
| 5332706 | Nowlin et al. | Jul 1994 | A |
| 5334677 | Razavi et al. | Aug 1994 | A |
| 5336795 | Lisowsky | Aug 1994 | A |
| 5349032 | Miyake et al. | Sep 1994 | A |
| 5349100 | Mintz | Sep 1994 | A |
| 5350653 | Shoshi et al. | Sep 1994 | A |
| 5350817 | Winter et al. | Sep 1994 | A |
| 5359015 | Jejelowo | Oct 1994 | A |
| 5360921 | Kiso et al. | Nov 1994 | A |
| 5362824 | Furtek et al. | Nov 1994 | A |
| 5371053 | Agapiou et al. | Dec 1994 | A |
| 5371158 | Breckner et al. | Dec 1994 | A |
| 5371259 | Meier et al. | Dec 1994 | A |
| 5372980 | Davis | Dec 1994 | A |
| 5373072 | Chang | Dec 1994 | A |
| 5374700 | Tsutsui et al. | Dec 1994 | A |
| 5374752 | Winter et al. | Dec 1994 | A |
| 5376697 | Johnston et al. | Dec 1994 | A |
| 5384298 | Inahara et al. | Jan 1995 | A |
| 5384299 | Turner et al. | Jan 1995 | A |
| 5387568 | Ewen et al. | Feb 1995 | A |
| 5391529 | Sangokoya | Feb 1995 | A |
| 5391629 | Turner et al. | Feb 1995 | A |
| 5391790 | Rohrmann et al. | Feb 1995 | A |
| 5393851 | Ewen et al. | Feb 1995 | A |
| 5395810 | Shamshoum et al. | Mar 1995 | A |
| 5397757 | Mink et al. | Mar 1995 | A |
| 5399450 | Matsushima et al. | Mar 1995 | A |
| 5399636 | Alt et al. | Mar 1995 | A |
| 5407835 | Adamczyk et al. | Apr 1995 | A |
| 5407882 | Yamada et al. | Apr 1995 | A |
| 5416178 | Winter et al. | May 1995 | A |
| 5416179 | Welch et al. | May 1995 | A |
| 5420320 | Zenk et al. | May 1995 | A |
| 5422325 | Jejelowo et al. | Jun 1995 | A |
| 5422409 | Brekner et al. | Jun 1995 | A |
| 5427991 | Turner | Jun 1995 | A |
| 5432242 | Baron | Jul 1995 | A |
| 5434115 | Yamada et al. | Jul 1995 | A |
| 5436305 | Alt et al. | Jul 1995 | A |
| 5439995 | Bailly et al. | Aug 1995 | A |
| 5439996 | Baird et al. | Aug 1995 | A |
| 5441920 | Welborn, Jr. | Aug 1995 | A |
| 5442019 | Agapiou et al. | Aug 1995 | A |
| 5442020 | Davis | Aug 1995 | A |
| 5444125 | Tomita et al. | Aug 1995 | A |
| 5444145 | Brant et al. | Aug 1995 | A |
| 5446221 | Struglinski | Aug 1995 | A |
| 5449732 | Smith et al. | Sep 1995 | A |
| 5504131 | Smith et al. | Apr 1996 | A |
| 5504132 | Smith et al. | Apr 1996 | A |
| 5539044 | Aysen et al. | Jul 1996 | A |
| 5541270 | Chinh et al. | Jul 1996 | A |
| 5559164 | Babu et al. | Sep 1996 | A |
| 5595001 | Schutte et al. | Jan 1997 | A |
| 5644007 | Davidson et al. | Jul 1997 | A |
| 5705577 | Rossi et al. | Jan 1998 | A |
| 5712365 | Arai et al. | Jan 1998 | A |
| 5716487 | Sumerak | Feb 1998 | A |
| 5962622 | Darnell et al. | Oct 1999 | A |
| 6015779 | Eaton et al. | Jan 2000 | A |
| 6160036 | Kommareddi et al. | Dec 2000 | A |
| 6168765 | Romatier et al. | Jan 2001 | B1 |
| 6320000 | Hurry et al. | Nov 2001 | B1 |
| Number | Date | Country |
|---|---|---|
| 2020375 | Jan 1991 | CA |
| 2118926 | Apr 1993 | CA |
| 19612226 | Oct 1996 | DE |
| 198 41 843 | Mar 2000 | DE |
| 0005215 | Nov 1979 | EP |
| 0108156 | May 1984 | EP |
| 2054819 | Feb 1981 | GB |
| WO9207013 | Apr 1992 | WO |
| WO9207014 | Apr 1992 | WO |
| WO9314852 | Aug 1993 | WO |
| WO9319101 | Sep 1993 | WO |
| WO9321239 | Oct 1993 | WO |
| WO9322355 | Nov 1993 | WO |
| WO9324423 | Dec 1993 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 20020192133 A1 | Dec 2002 | US |
| Number | Date | Country | |
|---|---|---|---|
| 60297931 | Jun 2001 | US |