A portable, self-contained sand blaster including a cabinet and accessory end caps. The caps include a solid end wall, an extension box for treating larger parts in the cabinet, a softboot with drawstring closure affixed about parts to be treated, and a softboot with a magnetic opening for attachment to rusted, relatively flat surfaces. The base is wheeled and has controls, a vacuum for dust, a sand supply, and a blast cabinet on top; the base includes connectors for hookup to electric power and a source of compressed air. A media filter screens out rust particles form the media.

1. Field of the Invention
The present invention relates to sand blasting cleaning devices, and more particularly to a portable, self-contained sand blasting cabinet with accessory end caps providing a wide range of cleaning operations, both inside the cabinet, inside an extended cabinet, and inside extensible shields which may be closed about a work area.
2. Description of the Related Art
There is a need in the art for a portable, self-contained sand blaster with an interchangeable end wall structure to accommodate an extended box to effectively lengthen the sand blaster cabinet, or a flexible, soft boot end cap with a drawstring end, or a magnetic end, to seal about a work object, all as provided by the instant invention but not taught or seen in the related art.
An anecdotal summary follows, indicating just one area where the instant invention solves an as yet unsolved major problem.
Vehicle repair in northern climates (upstate New York, for example) often involves dealing with rust and corrosion, caused by constant exposure to snow, salt and ice from fall to spring. In just dealing with brake systems alone, often rust and/or corrosion will impact the fit of a disc brake rotor to its hub, the fit of brake pads in their mounting brackets, and caliper movement on its mounts. The present art methodology in dealing with the problem is to grind off the rust by a labor intensive operation, usually involving an angle grinder and a wide variety of abrasive discs for each job. Not only is the process unduly long and tiresome, often hard-to-reach areas are missed and 10 to 20 discs may be used (these cost 60 to 80 cents each). Obviously, the process is costly. It is also environmentally unfriendly, as the discs create an airborne cloud of rust dust in the shop. The process can be dangerous to technicians"" eyes as well as lungs.
Now, some establishments simply absorb the extra cost, while other pass it on to their customers. Because of the costs involved, some simply do little or no cleaning of the parts, often resulting in an unsatisfactory brake job.
One answer is, of course, the use of a conventional, hand-held siphon feed sand blaster. Sandblasters do a fine and complete job of cleaning, even in hard to reach areas, and do not damage the underlying structure. This works just fine on any removable part, but is excessively messy and must be done outdoors, and presents obvious safety and environmental risks. Another answer is the use of a conventional sandblasting cabinet, again for the removable parts. However, these solutions do nothing for the parts that cannot be readily removed from the vehicle, namely (for example) the brake hub, calipers, and in some instances, the knuckle. Additionally, vehicle bodies are subjected to rust and corrosion. In the body shop environment, sandblasting would be a solution, but the job is messy and difficult to do on parts not readily removable from the vehicle.
The flexibility provided by the present invention, which allows sandblasting within a cabinet or on vehicle parts on the vehicle, by use of a novel, flexible boot attached to the sandblasting cabinet and sealable about the part to be treated, solves the problems set forth above. Additionally, the present invention provides an extension to the cabinet for handling and cleaning removable, extended length parts.
The related art discussed below fairly reflects the present state of the art.
A portable sandblasting device including a wheeled cabinet, a sandblasting gun and a vacuum to remove airborne dust particles from the operation is taught in U.S. Pat. No. 3,599,375 issued Aug. 17, 1971, to Frank D. Nunemaker. A sandblasting cabinet with a pair of glove ports is disclosed in U.S. Pat. No. Des. 323,661 issued Feb. 4, 1992, to Fred Zwicker.
U.S. Pat. No. 1,773,374 issued Aug. 19, 1930, to Richard Ruemelin shows a sandblasting hood movable up to the face of a stationary graveyard monument and generally sealed about the area to be sandblasted. A sand collection pail catches spent sand at a bottom of the hood.
A portable booth with glove ports and an internal system to prevent escape of cleaning fluids is seen in U.S. Pat. No. 4,993,199 issued Feb. 19, 1991, to Joel J. Hughes.
The remaining five patent documents to be discussed generally disclose abrasive blasting devices for large buildings or ships, and including a hood or shroud sealed up against a portion of the work surface to limit the escape of blast particles and collect the spent particles. These teachings include: U.S. Pat. No. 5,775,979 issued Jul. 7, 1998, to Dan A. Coke et al.; U.S. Pat. No. 5,038,527 issued Aug. 13, 1991, to Helmut Fasje; Japan Patent Document No. 52034496 published Mar. 16, 1977; Japan Patent Document No. 58077452 published May 10, 1983; and Japan Patent Document No. 63196379 published Aug. 15, 1988.
None of the above inventions and patents, taken either singularly or in combination, is seen to describe the instant invention as claimed. Thus a portable sand blasting cabinet and accessory end caps solving the aforementioned problems is desired.
The invention is a portable, self-contained sand blaster including a cabinet and accessory end caps. Parts to be treated by a sandblasting operation may be cleaned inside the cabinet, or inside extensions provided by the accessory end caps. The caps include a solid end wall, an extension box for treating larger parts in the cabinet, a softboot with drawstring closure affixed about parts to be treated and which cannot be conveniently removed and placed entirely within the cabinet, and a softboot with a magnetic opening for attachment to rather large, rusted or corroded (e.g., vehicle door panels), relatively flat surfaces.
The base is wheeled and has controls, a vacuum for safe evacuation of airborne dust particles, a bin or angled tube for the sand supply, and a blast cabinet on top. Conveniently, the base has a retractable electric cord with a male plug for hookup to a source of electricity. A source of compressed air is connected via a suitable connector to an air dryer and a compressed air line which leads to the sandblasting gun.
A media filter is located in a pullout tray at the base of the sandblasting cabinet. The filter has a mesh size sufficient to entrap large rust particles or parts that otherwise would reenter the sand stream and likely block the sandblasting gun during its use. If desired, a blow gun can be provided for cleaning dust off treated parts.
Accordingly, it is a principal object of the invention to provide a portable, self-contained sand blasting cabinet with accessory end caps, so that portable and fixed workpieces may be sandblasted within the cabinet or an end cap.
It is another object of the invention to provide a kit of end caps for a sandblasting cabinet, including a fixed wall, an extended length box for long workpieces, and a softboot end cap with a drawstring closure or magnets, for sealing an open end of the cap about a stationary work surface.
It is a further object of the invention to provide a portable sandblasting cabinet with an interior media filter above the sand supply which has a mesh size sufficient to block and entrap large particles from the sand supply, and thus prevent the sandblasting gun from becoming clogged by such debris and thus inoperable.
Still another object of the invention is to provide a portable sandblasting cabinet with a shop vacuum for dust, and operated by a knee-operable switch so that the sandblaster may be turned on and off by an operator without having to remove the hands from the gloves ports of the device.
It is an object of the invention to provide improved elements and arrangements thereof for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.

Portable sand blasting cabinet and accessory end caps


Proteasome inhibitors are useful for treating dry eye disorders and other disorders requiring the wetting of the eye.

The present invention is directed to the treatment of dry eye disorders. In particular, the present invention is directed to the use of proteasome inhibitors in the treatment of dry eye and other disorders requiring the wetting of the eye in mammals.
Dry eye, also known generically as keratoconjunctivitis sicca, is a common ophthalmological disorder affecting millions of Americans each year. The condition is particularly widespread among post-menopausal women due to hormonal changes following the cessation of fertility. Dry eye may afflict an individual with varying severity. In mild cases, a patient may experience burning, a feeling of dryness, and persistent irritation such as is often caused by small bodies lodging between the eye lid and the eye surface. In severe cases, vision may be substantially impaired. Other diseases, such as Sjogren""s disease and cicatricial pemphigoid manifest dry eye complications.
Although it appears that dry eye may result from a number of unrelated pathogenic causes, all presentations of the complication share a common effect, that is the breakdown of the pre-ocular tear film, which results in dehydration of the exposed outer surface and many of the symptoms outlined above (Lemp, Report of the National Eye Institute/Industry Workshop on Clinical Trials in Dry Eyes, The CLAO Journal, volume 21, number 4, pages 221-231 (1995)).
Practitioners have taken several approaches to the treatment of dry eye. One common approach has been to supplement and stabilize the ocular tear film using so-called artificial tears instilled throughout the day. Other approaches include the use of ocular inserts that provide a tear substitute or stimulation of endogenous tear production.
Examples of the tear substitution approach include the use of buffered, isotonic saline solutions, aqueous solutions containing water soluble polymers that render the solutions more viscous and thus less easily shed by the eye. Tear reconstitution is also attempted by providing one or more components of the tear film such as phospholipids and oils. Phospholipid compositions have been shown to be useful in treating dry eye; see, e.g., McCulley and Shine, Tear film structure and dry eye, Contactologia, volume 20(4), pages 145-49 (1998); and Shine and McCulley, Keratoconjunctivitis sicca associated with meibomian secretion polar lipid abnormality, Archives of Ophthalmology, volume 116(7), pages 849-52 (1998). Examples of phospholipid compositions for the treatment of dry eye are disclosed in U.S. Pat. Nos. 4,131,651 (Shah et al.), 4,370,325 (Packman), 4,409,205 (Shively), 4,744,980 and 4,883,658 (Holly), 4,914,088 (Glonek), 5,075,104 (Gressel et al.), 5,278,151 (Korb et al.), 5,294,607 (Glonek et al.), 5,371,108 (Korb et al.) and 5,578,586 (Glonek et al.). U.S. Pat. No. 5,174,988 (Mautone et al.) discloses phospholipid drug delivery systems involving phospholipids, propellants and an active substance.
U.S. Pat. No. 3,991,759 (Urquhart) discloses the use of ocular inserts in the treatment of dry eye. Other semi-solid therapy has included the administration of carrageenans (U.S. Pat. No. 5,403,841, Lang) which gel upon contact with naturally occurring tear film.
Another approach involves the provision of lubricating substances in lieu of artificial tears. For example, U.S. Pat. No. 4,818,537 (Guo) discloses the use of a lubricating, liposome-based composition, and U.S. Pat. No. 5,800,807 (Hu et al.) discloses compositions containing glycerin and propylene glycol for treating dry eye.
Aside from efforts directed primarily to the alleviation of symptoms associated with dry eye, methods and compositions directed to treatment of the dry eye condition have also been pursued. For example, U.S. Pat. No. 5,041,434 (Lubkin) discloses the use of sex steroids, such as conjugated estrogens, to treat dry eye conditions in post-menopausal women; U.S. Pat. No. 5,290,572 (MacKeen) discloses the use of finely divided calcium ion compositions to stimulate pre-ocular tear film production; and U.S. Pat. No. 4,966,773 (Gressel et al.) discloses the use of microfine particles of one or more retinoids for ocular tissue normalization.
Although these approaches have met with some success, problems in the treatment of dry eye nevertheless remain. The use of tear substitutes, while temporarily effective, generally requires repeated application over the course of a patient""s waking hours. It is not uncommon for a patient to have to apply artificial tear solution ten to twenty times over the course of the day. Such an undertaking is not only cumbersome and time consuming, but is also potentially very expensive. Transient symptoms of dry eye associated with refractive surgery have been reported to last in some cases from six weeks to six months or more following surgery.
The use of ocular inserts is also problematic. Aside from cost, they are often unwieldy and uncomfortable. Further, as foreign bodies introduced in the eye, they can be a source of contamination leading to infections. In situations where the insert does not itself produce and deliver a tear film, artificial tears must still be delivered on a regular and frequent basis.
The 20S proteasome is a complex of several enzymes that functions to degrade certain cellular proteins. Besides its involvement in the removal of misfolded or otherwise abnormal proteins, the proteasome also constitutes an integral part of several signaling mechanisms. One of these pathways involves inflammatory responses mediated by the nuclear transcription factor NF-xcexaB. In its quiescent state NF-xcexaB exists as a heterodimer with the protein Ixcexa-Bxcex1, which masks the nuclear localization signals and DNA binding domain of the former protein. Under inflammatory conditions Ixcexa-Bxcex1 is phosphorylated, causing a conformational change which results in its tagging with multiple copies of the ubiquitin protein. Ubiquinated Ixcexa-Bxcex1 is recognized and degraded by the proteasome, which liberates NF-xcexaB. The free protein is translocated to the nucleus, where it binds to the appropriate DNA sequence and upregulates the production of several inflammatory mediators, such as COX-2, iNOS, IL-1, and TNF-xcex1. Inhibiting the activity of the proteasome may therefore represent a potential strategy for reducing excessive inflammation.
Some recent literature reports suggest that patients suffering from dry eye syndrome disproportionately exhibit the hallmarks of excessive inflammation in relevant ocular tissues, such as the lacrimal and meibomian glands. The use of the following types of pharmaceutically active compounds to treat dry eye patients has been disclosed: steroids [e.g. U.S. Pat. No. 5,958,912; Marsh, et al., Topical nonpreserved methylprednisolone therapy for keratoconjunctivitis sicca in Sjogren syndrome, Ophthalmology, 106(4): 811-816 (1999); Pflugfelder, et. al. U.S. Pat. No. 6,153,607], cytokine release inhibitors (Yanni, J. M.; et. al. WO 0003705 A1), cyclosporine A [(Tauber, J. Adv. Exp. Med. Biol. 1998, 438 (Lacrimal Gland, Tear Film, and Dry Eye Syndromes 2), 969], and 15-HETE (Yanni et. al., U.S. Pat. No. 5,696,166). Additionally, while proteasome inhibitors, have been disclosed as antiinflammatory agents for the treatment of various non-ocular (e.g., septic shock, ischemia-reperfusion injury, cancer, and graft rejection; see U.S. Pat. No. 6,083,903, WO 0043000, WO 0064863, WO 9922729, WO 9915183, WO 9835691, and WO 9632105) and ocular diseases (glaucoma and damage due to ocular surgery; see Jpn. Kokai Tokkyo Koho JP 10036289 A2, Chemical Abstracts Accession Number 128:226254), the use of proteasome inhibitors for the treatment of dry eye syndrome has not been previously suggested or disclosed.
The present invention is directed to methods for the treatment of dry eye and other disorders requiring the wetting of the eye, including symptoms of dry eye associated with refractive surgery such as LASIK surgery. According to the methods of the present invention, proteasome inhibitors are administered to a patient suffering from dry eye or other disorders requiring wetting of the eye. The proteasome inhibitors are preferably administered topically to the eye.
Many proteasome inhibitors are known. Proteasome inhibitors useful in the methods of the present invention are those of formulas (I)-(III).
wherein:
R is H, alkyl, or acyl;
R1 is OR4, where R4 is H or acyl, and R2 is SR5, where R5 is alkyl, cycloalkyl, aryl, alkenyl, alkynyl, cycloalkenyl, heterocycloalkyl, or heterocycloalkenyl, all optionally containing one or more alkyl, halo, amino, acylamino, aminoacyl, hydroxyl, acyloxy, alkoxy, aryloxy, carboxyl, alkoxycarbonyl, or acyl groups; or
R1 is O and R2 is bonded to R1 to form a xcex2-lactone ring; and
R3 is CH3, C2H5, n- or i-C3H7, or n- or i-C4H9.
wherein:
P is morpholinylcarbonyl or 2- or 8-quinolinyl-, 2-quinoxalinyl-, 2- or 3-pyridyl-, piperazinyl-, 3-furanyl-, or 3-pyrrolylcarbonyl or -sulfonyl;
X2 is CONH, CH2NH, CH(OH)CH2, CH(OH)CH(OH), CH(OH)CH2NH, CH:CH, COCH2, SO2NH, SO2CH2, or CH(OH)CH2CONH;
R is H or alkyl;
R2 and R3 are the same or different and are H, alkyl, cycloalkyl, aryl, heterocyclyl, CH2R5, or alkyl-chalcogen;
R5 is aryl, aralkyl, alkaryl, cycloalkyl, or heterocyclyl; and
Z1 and Z2 are the same or different and are alkyl, hydroxy, alkoxy, or aryloxy.
wherein:
A and Z represent a bond or an optionally substituted amino acid moiety;
R1 is H, an amino protecting group (such as t-butoxycarbonyl or 9-fluorenylmethylcarbonyl), or a group R5Y, where R5 is H or a heterocyclylalkyl group and Y is CO, NHCO, NHCS, SO2, OCO, or OCS;
R2 represents the side chain of a natural amino acid or is alkyl, arylalkyl, heteroarylalkyl, cycloalkylalkyl, trimethylsilylmethyl, 2-thienylmethyl, or styrylmethyl;
R3 is halo, alkyl, alkoxy, or hydroxyalkoxy; and
R4 is (2R)-hydroxyindan-(1S)-yl, (S)-2-hydroxy-1-phenylethyl, or 2-hydroxybenzyl, the phenyl rings of each being optionally substituted in the 4-position with a methoxy group.
The compounds of formulas (I)-(III) are known and can be made by known methods. For example, the synthesis of compounds included in formula (I) is disclosed in Adams, et al., J. Am. Chem. Soc., 121:9967 (1999). The synthesis of compounds included in formula (II) is disclosed in U.S. Pat. No. 6,083,903. The synthesis of compounds included in formula (III) is disclosed in WO 0064863.
Included within the scope of the present invention are the individual enantiomers of the compounds of the present invention, as well as their racemic and non-racemic mixtures. The individual enantiomers can be enantioselectively synthesized from the appropriate enantiomerically pure or enriched starting material by means such as those described below. Alternatively, they may be enantioselectively synthesized from racemic/non-racemic or achiral starting materials. (Asymmetric Synthesis; J. D. Morrison and J. W. Scott, Eds.; Academic Press Publishers: New York, 1983-1985, volumes 1-5; Principles of Asymmetric Synthesis; R. E. Gawley and J. Aube, Eds.; Elsevier Publishers: Amsterdam, 1996). They may also be isolated from racemic and non-racemic mixtures by a number of known methods, e.g. by purification of a sample by chiral HPLC (A Practical Guide to Chiral Separations by HPLC; G. Subramanian, Ed.; VCH Publishers: New York, 1994; Chiral Separations by HPLC; A. M. Krstulovic, Ed.; Ellis Horwood Ltd. Publishers, 1989), or by enantioselective hydrolysis of a carboxylic acid ester sample by an enzyme (Ohno, M.; Otsuka, M. Organic Reactions, volume 37, page 1 (1989)). Those skilled in the art will appreciate that racemic and non-racemic mixtures may be obtained by several means, including without limitation, nonenantioselective synthesis, partial resolution, or even mixing samples having different enantiomeric ratios. Departures may be made from such details within the scope of the accompanying claims without departing from the principles of the invention and without sacrificing its advantages. Also included within the scope of the present invention are the individual isomers substantially free of their respective enantiomers.
The term xe2x80x9cacylxe2x80x9d represents a group that is linked by a carbon atom that has a double bond to an oxygen atom and a single bond to another carbon atom.
The term xe2x80x9calkylxe2x80x9d includes straight or branched chain aliphatic hydrocarbon groups that are saturated and have 1 to 10 carbon atoms. The alkyl groups may be interrupted by one or more heteroatoms, such as oxygen, nitrogen, or sulfur, and may be substituted with other groups, such as halogen, hydroxyl, aryl, cycloalkyl, aryloxy, or alkoxy. Preferred straight or branched alkyl groups include methyl, ethyl, propyl, isopropyl, butyl and t-butyl.
The term xe2x80x9ccycloalkylxe2x80x9d includes straight or branched chain, saturated or unsaturated aliphatic hydrocarbon groups which connect to form one or more rings, which can be fused or isolated. The rings may be substituted with other groups, such as halogen, hydroxyl, aryl, aryloxy, alkoxy, or lower alkyl; Preferred cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl.
The term xe2x80x9cheterocycloalkylxe2x80x9d refers to cycloalkyl rings that contain at least one heteroatom such as O, S, or N in the ring, and can be fused or isolated. The rings may be substituted with other groups, such as halogen, hydroxyl, aryl, aryloxy, alkoxy, or lower alkyl. Preferred heterocycloalkyl groups include pyrrolidinyl, tetrahydrofuranyl, piperazinyl, and tetrahydropyranyl.
The term xe2x80x9calkenylxe2x80x9d includes straight or branched chain hydrocarbon groups having 1 to 10 carbon atoms with at least one carbon-carbon double bond, the chain being optionally interrupted by one or more heteroatoms. The chain hydrogens may be substituted with other groups, such as halogen. Preferred straight or branched alkenyl groups include allyl, 1-butenyl, 1-methyl-2-propenyl and 4-pentenyl.
The term xe2x80x9ccycloalkenylxe2x80x9d includes straight or branched chain, saturated or unsaturated aliphatic hydrocarbon groups which connect to form one or more non-aromatic rings containing a carbon-carbon double bond, which can be fused or isolated. The rings may be substituted with other groups, such as halogen, hydroxyl, alkoxy, or lower alkyl. Preferred cycloalkenyl groups include cyclopentenyl and cyclohexenyl.
The term xe2x80x9cheterocycloalkenylxe2x80x9d refers to cycloalkenyl rings which contain one or more heteroatoms such as O, N, or S in the ring, and can be fused or isolated. The rings may be substituted with other groups, such as halogen, hydroxyl, aryl, aryloxy, alkoxy, or lower alkyl. Preferred heterocycloalkenyl groups include pyrrolidinyl, dihydropyranyl, and dihydrofuranyl.
The term xe2x80x9ccarbonyl groupxe2x80x9d represents a carbon atom double bonded to an oxygen atom, wherein the carbon atom has two free valencies.
The term xe2x80x9caminocarbonylxe2x80x9d represents a free or functionally modified amino group bonded from its nitrogen atom to the carbon atom of a carbonyl group, the carbonyl group itself being bonded to another atom through its carbon atom.
The term xe2x80x9clower alkylxe2x80x9d represents alkyl groups containing one to six carbons (C1-C6).
The term xe2x80x9chaloxe2x80x9d or xe2x80x9chalogenxe2x80x9d represents fluoro, chloro, bromo, or iodo.
The term xe2x80x9carylxe2x80x9d refers to carbon-based rings which are aromatic. The rings may be isolated, such as phenyl, or fused, such as naphthyl. The ring hydrogens may be substituted with other groups, such as lower alkyl, halogen, free or functionalized hydroxy, trihalomethyl, etc. Preferred aryl groups include phenyl, 3-(trifluoromethyl)phenyl, 3-chlorophenyl, and 4-fluorophenyl.
The term xe2x80x9cheteroarylxe2x80x9d refers to aromatic hydrocarbon rings which contain at least one heteroatom such as O, S, or N in the ring. Heteroaryl rings may be isolated, with 5 to 6 ring atoms, or fused, with 8 to 10 atoms. The heteroaryl ring(s) hydrogens or heteroatoms with open valency may be substituted with other groups, such as lower alkyl or halogen. Examples of heteroaryl groups include imidazole, pyridine, indole, quinoline, furan, thiophene, pyrrole, tetrahydroquinoline, dihydrobenzofuran, and dihydrobenzindole.
The terms xe2x80x9caryloxyxe2x80x9d, xe2x80x9cheteroaryloxyxe2x80x9d, xe2x80x9calkoxyxe2x80x9d, xe2x80x9ccycloalkoxyxe2x80x9d, xe2x80x9cheterocycloalkoxyxe2x80x9d, xe2x80x9calkenyloxyxe2x80x9d, xe2x80x9ccycloalkenyloxyxe2x80x9d, xe2x80x9cheterocycloalkenyloxyxe2x80x9d, and xe2x80x9calkynyloxyxe2x80x9d represent an aryl, heteroaryl, alkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, or alkynyl group, respectively, attached through an oxygen linkage.
The terms xe2x80x9calkoxycarbonylxe2x80x9d, xe2x80x9caryloxycarbonylxe2x80x9d, xe2x80x9cheteroaryloxycarbonylxe2x80x9d, xe2x80x9ccycloalkoxycarbonylxe2x80x9d, xe2x80x9cheterocycloalkoxycarbonylxe2x80x9d, xe2x80x9calkenyloxycarbonylxe2x80x9d, xe2x80x9ccycloalkenyloxycarbonylxe2x80x9d, xe2x80x9cheterocycloalkenyloxycarbonylxe2x80x9d, and xe2x80x9calkynyloxycarbonylxe2x80x9d represent an alkoxy, aryloxy, heteroaryloxy, cycloalkoxy, heterocycloalkoxy, alkenyloxy, cycloalkenyloxy, heterocycloalkenyloxy, or alkynyloxy group, respectively, bonded from its oxygen atom to the carbon of a carbonyl group, the carbonyl group itself being bonded to another atom through its carbon atom.
Preferred for purposes of the present invention are those compounds of formula I wherein:
R is H, CH3CO, C2H5CO, Me3CCO, or PhCO;
R1 is OR4, where R4 is H, CH3CO, C2H5CO, Me3CCO, or PhCO, and R2 is SR5, where R5 is a defined above; or
R1 is O and R2 is bonded to R1 to form a xcex2-lactone ring; and
R3 is CH3, C2H5, n- or i-C3H7, or n- or i-C4H9.
Among the most preferred compounds of the present invention are the following compounds 1-4 (where Ac=an acetyl group):
The syntheses of these compounds are disclosed in: Corey et.al., Total Synthesis and Biological Activity of Lactacystin, Omuralide, and Analogs. Chem. Pharm. Bull., volume 47, pages 1-10 (1999); and Adams et. al., A Novel and Efficient Synthesis of a Highly Active Analogue of clasto-Lactacystin xcex2-Lactone. J. Am. Chem. Soc., volume 121pages 9967-9976 (1999).
According to the methods of the present invention, a composition comprising one or more proteasome inhibitors and a pharmaceutically acceptable carrier for topical ophthalmic administration or implantation into the conjunctival sac or anterior chamber of the eye is administered to a mammal in need thereof. The compositions are formulated in accordance with methods known in the art for the particular route of administration desired.
The compositions administered according to the present invention comprise a pharmaceutically effective amount of one or more proteasome inhibitors. As used herein, a xe2x80x9cpharmaceutically effective amountxe2x80x9d is one which is sufficient to reduce or eliminate signs or symptoms of dry eye or other disorders requiring the wetting of the eye. Generally, for compositions intended to be administered topically to the eye in the form of eye drops or eye ointments, the total amount of proteasome inhibitor will be about 0.0001 to 10 percent weight/volume (xe2x80x9c% w/vxe2x80x9d). For preferred topically administrable ophthalmic compositions, the total amount of proteasome inhibitor will be about 0.001-1% w/v.
The present invention is particularly directed to compositions useful in treating dry eye. Preferably, such compositions will be formulated as solutions, suspensions and other dosage forms for topical administration. Aqueous solutions are generally preferred, based on ease of formulation, as well as a patient""s ability to easily administer such compositions by means of instilling one to two drops of the solutions in the affected eyes. However, the compositions may also be suspensions, viscous or semi-viscous gels, or other types of solid or semi-solid compositions. Suspensions may be preferred for proteasome inhibitors which are sparingly soluble in water.
The compositions of the present invention may also contain a surfactant. Various surfactants useful in topical ophthalmic formulations may be employed. The surfactant(s) may provide additional chemical stabilization of the compounds of formulas (I)-(III) and may further provide for the physical stability of the compounds. In other words, the surfactants may aid in preventing chemical degradation of the compounds of formulas (I)-(III) and also prevent the compounds from binding to the containers in which their compositions are packaged. As used herein, xe2x80x9can effective concentration of surfactant(s)xe2x80x9d refers to a concentration that enhances the chemical and physical stability of the compounds of formulas (I)-(III). Examples of surfactants include, but are not limited to: Cremophor(copyright) EL, polyoxyl 20 ceto stearyl ether, polyoxyl 40 hydrogenated castor oil, polyoxyl 23 lauryl ether and poloxamer 407 may be used in the compositions. A preferred surfactant is polyoxyl 40 stearate. The concentration of surfactant will vary, depending on the concentration of the compound(s) of formulas (I)-(III) and optional ethanol present in the formulation. In general, however, the surfactant(s) concentration will be about 0.001 to 2.0% w/v. Preferred compositions of the present invention will contain about 0.1% w/v of polyoxyl 40 stearate.
The compositions of the present invention may also include various other ingredients, such as tonicity agents, buffers, preservatives, co-solvents and viscosity building agents.
Various tonicity agents may be employed to adjust the tonicity of the composition, preferably to that of natural tears for ophthalmic compositions. For example, sodium chloride, potassium chloride, magnesium chloride, calcium chloride, dextrose and/or mannitol may be added to the composition to approximate physiological tonicity. Such an amount of tonicity agent will vary, depending on the particular agent to be added. In general, however, the compositions will have a tonicity agent in an amount sufficient to cause the final composition to have an ophthalmically acceptable osmolality (generally about 150-450 mOsm, preferably 250-350 mOsm).
An appropriate buffer system (e.g., sodium phosphate, sodium acetate, sodium citrate, sodium borate or boric acid) may be added to the compositions to prevent pH drift under storage conditions. The particular concentration will vary, depending on the agent employed. Preferably, however, the buffer will be chosen to maintain a target pH within the range of pH 6-7.5.
Antioxidants may be added to compositions of the present invention to protect the proteasome inhibitor compounds from oxidation during storage. Examples of such antioxidants include, but are not limited to, vitamin E and analogs thereof, ascorbic acid and derivatives, and butylated hydroxyanisole (BHA).
Compositions formulated for the treatment of dry eye-type diseases and disorders may also comprise aqueous carriers designed to provide immediate, short-term relief of dry eye-type conditions. Such carriers can be formulated as a phospholipid carrier or an artificial tears carrier, or mixtures of both. As used herein, xe2x80x9cphospholipid carerxe2x80x9d and xe2x80x9cartificial tears carrierxe2x80x9d refer to aqueous compositions which: (i) comprise one or more phospholipids (in the case of phospholipid carriers) or other compounds, which lubricate, xe2x80x9cwet,xe2x80x9d approximate the consistency of endogenous tears, aid in natural tear build-up, or otherwise provide temporary relief of dry eye symptoms and conditions upon ocular administration; (ii) are safe; and (iii) provide the appropriate delivery vehicle for the topical administration of an effective amount of one or more proteasome inhibitors. Examples or artificial tears compositions useful as artificial tears carriers include, but are not limited to, commercial products, such as Tears Naturale(copyright), Tears Naturale II(copyright), Tears Naturale Free(copyright), and Bion Tears(copyright) (Alcon Laboratories, Inc., Fort Worth, Tex.). Examples of phospholipid carrier formulations include those disclosed in U.S. Pat. Nos. 4,804,539 (Guo et al.), 4,883,658 (Holly), 4,914,088 (Glonek), 5,075,104 (Gressel et al.), 5,278,151 (Korb et al.), 5,294,607 (Glonek et al.), 5,371,108 (Korb et al.), 5,578,586 (Glonek et al.); the foregoing patents are incorporated herein by reference to the extent they disclose phospholipid compositions useful as phospholipid carriers of the present invention.
Other compounds designed to lubricate, xe2x80x9cwet,xe2x80x9d approximate the consistency of endogenous tears, aid in natural tear build-up, or otherwise provide temporary relief of dry eye symptoms and conditions upon ocular administration the eye are known in the art. Such compounds may enhance the viscosity of the composition, and include, but are not limited to: monomeric polyols, such as, glycerol, propylene glycol, ethylene glycol; polymeric polyols, such as, polyethylene glycol, hydroxypropylmethyl cellulose (xe2x80x9cHPMCxe2x80x9d), carboxy methylcellulose sodium, hydroxy propylcellulose (xe2x80x9cHPCxe2x80x9d), dextrans, such as, dextran 70; water soluble proteins, such as gelatin; and vinyl polymers, such as, polyvinyl alcohol, polyvinylpyrrolidone, povidone and carbomers, such as, carbomer 934P, carbomer 941, carbomer 940, carbomer 974P.
Other compounds may also be added to the ophthalmic compositions of the present invention to increase the viscosity of the carrier. Examples of viscosity enhancing agents include, but are not limited to: polysaccharides, such as hyaluronic acid and its salts, chondroitin sulfate and its salts, dextrans, various polymers of the cellulose family; vinyl polymers; and acrylic acid polymers. In general, the phospholipid carrier or artificial tears carrier compositions will exhibit a viscosity of 1 to 400 centipoises (xe2x80x9ccpsxe2x80x9d).
Topical ophthalmic products are typically packaged in multidose form. Preservatives are thus required to prevent microbial contamination during use. Suitable preservatives include: benzalkonium chloride, chlorobutanol, benzododecinium bromide, methyl paraben, propyl paraben, phenylethyl alcohol, edetate disodium, sorbic acid, polyquaternium-1, or other agents known to those skilled in the art. Such preservatives are typically employed at a level of from 0.001 to 1.0% w/v. Unit dose compositions of the present invention will be sterile, but typically unpreserved. Such compositions, therefore, generally will not contain preservatives.
The preferred compositions of the present invention are intended for administration to a human patient suffering from dry eye or symptoms of dry eye. Preferably, such compositions will be administered topically. In general, the doses used for the above described purposes will vary, but will be in an effective amount to increase mucin production in the eye and thus eliminate or improve dry eye conditions. Generally, 1-2 drops of such compositions will be administered 1-10 times per day for the treatment of dry eye or other ocular disease or disorder. Preferably, 1-2 drops of the compositions will be administered 1-4 times per day.
A representative eye drop formulation is provided in Example 1 below.

Use of proteasome inhibitors to treat dry eye disorders


This application discloses triphenyl carbenium NCA""s as catalyst activators for a class of asymmetrically bridged hafnocene catalyst precursors. These catalyst precursors are activated into olefin polymerization catalysts and are suitable for gas, solution, and slurry-phase polyermization reactions. The disclosed bridge is methylenyl- or silanylenyl-based and is optionally, alkyl or aryl substituted. The catalytic activity of the disclosed hafnocene catalyst precursors is substantially enhanced over identical catalysts that are activated with other activators.

This invention relates to olefin copolymerization processes using substituted hafnocene catalyst compounds with noncoordinating anions.
Olefin polymers comprising ethylene and at least one or more xcex1-olefin and optionally one or more diolefin make up a large segment of polyolefin polymers and will be addressed as xe2x80x9cethylene copolymersxe2x80x9d herein. Such polymers range from crystalline polyethylene copolymers to largely amorphous elastomers, with a new area of semi-crystalline xe2x80x9cplastomersxe2x80x9d in between. In particular, ethylene copolymer plastomers are now a well-established class of industrial polymers having a variety of uses associated with their unique properties, such as elastomeric properties and their thermo-oxidative stability. Uses of the plastomers include general thermoplastic olefins, films, wire and cable coatings, polymer modification (by inclusion in blends with other polyolefins), injection molding, foams, footwear, sheeting, functionalized polymers (such as by free-radical graft addition of polar monomers) and components in adhesive and sealant compounds.
Commercially prepared ethylene copolymers have traditionally been made via Ziegler-Natta polymerization with catalyst systems largely based on vanadium or titanium. Newer metallocene catalyst compounds have received attention due to their facile incorporation of larger monomer incorporation and potential increases in polymerization activities. U.S. Pat. No. 5,324,800 describes metallocenes having substituted and unsubstituted cyclopentadienyl ligands which are suitable for producing high molecular weight olefin polymers, including linear, low density copolymers of ethylene with minor amounts of xcex1-olefin.
Additionally, polypropylene is an important industrial polymer. To the extent that catalysts for these polymerizations can be improved, their use provides economic benefit.
Noncoordinating anions useful as catalyst components with such metallocenes are known. The term xe2x80x9cnoncoordinating anionxe2x80x9d is now accepted terminology in the field of olefin polymerization, both by coordination or insertion polymerization and carbocationic polymerization. The noncoordinating anions function as electronic stabilizing cocatalysts, or counterions, for cationic metallocenes which are active for olefin polymerization. The term xe2x80x9cnoncoordinating anionxe2x80x9d as used here and in the references applies both to noncoordinating anions and weakly coordinating anions that coordinate weakly enough to the cationic complex so as to be labile to replacement by olefinically or acetylenically unsaturated monomers at the insertion site. U.S. Pat. No. 5,198,401 describes a preferred noncoordinating anion tetra(perflourophenyl) boron, [B(pfp)4]- or [B(C6F5)4]-, wherein the perfluorinated phenyl ligands on the boron make the counterion labile and stable to possible adverse reactions with the metal cation complexes.
The utility of metallocene-based ionic catalysts in high temperature olefin polymerization is described in U.S. Pat. Nos. 5,408,017 and 5,767,208, EP 0 612 768, and WO 96/33227. Each addresses suitable metallocene catalysts for high temperature processes for olefin copolymerization. High molecular weight ethylene/xcex1-olefin copolymers is an objective of EP 0 612 768 and is addressed with catalyst systems based on bis(cyclopentadienyl/indenyl/fluorenyl) hafnocenes which are combined with an alkyl aluminum compound and an ionizing ionic compound providing a non-coordinating anion.
Improved catalyst systems for olefin polymerization are industrial useful.
The invention thus addresses specifically substituted, bridged hafnocene catalyst complexes activated with cocatalysts in which specific choices of catalyst and activator lead to unexpectedly high catalysis activities such that olefin copolymers and copolymers can be prepared at surprisingly high production rates. More specifically, the invention relates to catalysts for polymerizing olefins under supercritical or solution polymerization conditions at a reaction temperature at, or above, 60xc2x0 C to 225xc2x0 C, or below. Specific monomers useful in the invention include ethylene and/or propylene and one or more comonomers capable of insertion polymerization with a hafnocene catalyst complex derived from A) a biscyclopentadienyl hafnium organometallic compound having i) at least one unsubstituted cyclopentadienyl ligand or aromatic fused-ring substituted cyclopentadienyl ligand not having additional substitutents on said ligand, ii) one substituted or unsubstituted, aromatic fused-ring substituted cyclopentadienyl ligand, and iii) a covalent bridge connecting the two cyclopentadienyl ligands where the bridge has a single carbon or silicon atom plus additional moities that complete carbon or silicon""s valence; and B) an activating cocatalyst, preferably a precursor ionic compound comprising a halogenated tetraaryl-substituted Group 13 anion and a carbenium cation.
Definitions
Carbenium cations are cations in which carbon has a formal valence of 3 leaving it with a +1 charge. Such a species is highly Lewis acidic and is a useful metallocene activator. Isoelectronic or isostructural cations in which the carbon is replaced with for example Si are also useful.
Cyclopentadienyl ligands: Cyclopentadienyl ligands are those ligands that have a cyclopentadiene anion core. These can be unsubstituted or substituted with hydrocarbyl groups as defined below. They can be part of fused-ring systems such as indenyl and fluorenyl. Similarly the use of hetero-atom containing cyclopentadienyl rings or fused rings, where a non-carbon Group 14, 15 or 16 atom replaces one of the ring carbons in the cyclopentadienyl ring or in a ring fused with the cyclopentadienyl ring is within the scope of cyclopentadienyl. The important component of a cyclopentadienyl ligand for this disclosure is the aromatic, substantially planar, five-membered ring of the cyclopentadienide anion. The terms xe2x80x9cindenylxe2x80x9d and xe2x80x9cfluorenylxe2x80x9d ligands are therefore within the scope of cyclopentadienyl. When this disclosure wishes to refer to cyclopentadienide itself, it uses cyclopentadienide or cyclopentadine anion. See, for example, the teachings of WO 98/37106, having common priority with U.S. Ser. No. 08/999,214, filed Dec. 29, 1997, now U.S Pat. No. 6,451,938 and WO 98/41530, having common priority with U.S. Ser. No. 09/042,378, filed Mar. 13, 1998, now abandoned incorporated by reference for purposes of U.S. patent practice.
Cyclopentadienyl substitutions R and Rxe2x80x2, typically include one or more C1 to C30 hydrocarbon or hydrocarbylsilyl groups selected from linear, branched, cyclic, aliphatic, aromatic or combined structure groups, including fused-ring or pendant configurations. Examples include methyl, isopropyl, n-propyl, n-butyl, isobutyl, tertiary butyl, neopentyl, phenyl, n-hexyl, cyclohexyl, and benzyl.
T is a bridge with two aryl groups, each substituted with a C1-C20 hydrocarbyl or hydrocarbylsilyl group at least one of which is a linear C3 or greater substitutent The bridge substituents preferably comprise C1-C20 linear or branched alkyl, or C1-C20 substituted-silyl, substituted phenyl groups, the alkyl or substituted-silyl substituents located in the para- or meta-positions of the aryl groups, preferably wherein at least one of said alkyl substituents is a C3 or higher linear n-alkyl substitutent, preferably C4 or higher. Specific examples include methyl, ethyl, n-propyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, neopentyl, etc.
Q are hafnocene ligands that can be abstracted by the activator and are ligands that a olefin monomer can insert into as polymerization occurs. Q substituents specifically include fluorinated aryl groups, preferably perfluorinated aryl groups, and include substituted Q groups having substituents additional to the fluorine substitution, such as fluorinated hydrocarbyl groups. Preferred fluorinated aryl groups include phenyl, biphenyl, napthyl, and derivatives thereof. The disclosures of U.S. Pat. Nos. 5,198,401, 5,296,433, 5,278,119, 5,447,895, 5,688,634, 5,895,771, WO 93/02099, WO 97/29845, WO 99/43717, WO 99/42467 and copending U.S. application Ser. No. 09/261,627, filed Mar. 3, 1999 now U.S. Ser. No. 6,262,202, and its equivalent WO 99/45042 are particularly instructive as to suitable Q substituents and are incorporated by reference for purposes of U.S. patent practice.
Hydrocarbyl: For the purposes of this application the term xe2x80x9chydrocarbonxe2x80x9d or xe2x80x9chydrocarbylxe2x80x9d is meant to include those compounds or groups that have essentially hydrocarbon characteristics but optionally contain not more than about 10 mol. % non-carbon atoms, such as boron, silicon, oxygen, nitrogen, sulfur and phosphorous. xe2x80x9cHydrocarbylsilylxe2x80x9d is exemplified by, but not limited to, dialkyl- and trialkylsilyls.
Alkyl is a radical based on an aliphatic hydrocarbon. This backbone can be substituted by any number of other alkyl or aryl substituents as is known in the art.
Aryl is a radical based on an aromatic hydrocarbon. This backbone can be substituted by any number of other aryl or alkyl substituents as is known in the art.
NCA is a non-coordinating ion. This term encompasses anions that are coordinating but only weakly so. The key is that incoming olefin monomer is capable of replacing NCA during a polymerization process.
The bridged hafnium compounds of the invention include those having a single substituted carbon or silicon atom bridging two cyclopentadienyl-containing (Cp) ligands of the hafnium metal centers. The Cp ligands are either substituted or unsubstituted, preferrably substituted. The bridge is either methyleneyl or silylenyl-based and is substituted or unsubstituted, preferably substituted.
Specific bridged hafnium catalysts include those derived from: (1) indenyl-based complexes such as the isomers, or mixtures, of (para-n-butylphenyl)(para-t-butylphenyl)methylene(fluorenyl)(indenyl)hafnium dimethyl, (para-n-propylphenyl)(para-methylphenyl)methylene(fluorenyl)(indenyl)hafnium dimethyl, di(para-n-butylphenyl)methylene (2,7-di tertbutylfluorenyl)(indenyl)hafnium dimethyl, (para-n-butylphenyl)(para-t-butylphenyl)methylene (2,7-di tertbutylfluorenyl)(indenyl)hafnium dimethyl, (para-n-butylphenyl)(para-t-butylphenyl)methylene (2,7-dimethylfluorenyl)(indenyl)hafnium dibenzyl and di(para-n-butylphenyl)methylene(fluorenyl)(indenyl)hafnium dimethyl; and, (2) fluorenyl-based complexes such as (para-n-propylphenyl)(para-i-propylphenyl)silyl(fluorenyl)(fluorenyl)hafnium di-t-butyl, di(para-n-propylphenyl)methylene (2,7-di-tert-butyl-5-methylfluorenyl)(fluorenyl)hafnium dimethyl; and (3) cyclopentadienyl-based complexes such as the isomers, or mixtures, of (para-n-propylphenyl)(para-i-propylphenyl)methylene(fluorenyl)(cyclopentadienyl)hafnium dimethyl, (para-n-butylphenyl)(para-t-butylphenyl)methylene(fluorenyl)(cyclopentadienyl)hafnium dimethyl, di(para-n-butylphenyl)methylene (2,7-di tertbutylfluorenyl)(cyclopentadienyl)hafnium dimethyl, (para-n-butylphenyl)(para-t-butylphenyl)methylene (2,7-di tertbutylfluorenyl)(cyclopentadienyl)hafnium dimethyl, and di(para-n-butylphenyl)methylene (2,7-dimethyl fluorenyl)(cyclopentadienyl)hafnium dimethyl or dibenzyl. It has been found that the substituted bridge-containing compounds, such as those asymmetric compounds listed above, are particularly useful in accordance with the invention.
The invention, activating cocatalyst precursor, ionizing compounds comprise Group 13 element complexes having at least two halogenated aromatic ligands such as the halogenated tetraphenyl boron and aluminum compounds exemplified in the identified prior art.
Those anions with mixed ligands are also suitable. Tris(perfluorophenyl)(perfluoronapthyl)borate is an illustrative complex. Thus, generically speaking, the Group 13 complexes useful in a accordance with the invention will typically conform to the following formula:
[M(A)4xe2x88x92n(C)n]xe2x88x92
where, M is a Group 13 element, A is an nonhindering ligand as described above, C is a hindering ligand, one having bulky substitutents on the closest aryl ring bonded to the metal/metalloid center other than those described as suitable above, and n=0, 1, or 2. See also copending application U.S. Ser. No. 60/087447, filed Jun. 1, 1998, and its equivalent WO 99/45042, the teachings of which are referred to and incorporated by reference for purposes of U.S. patent practice.
For both fused aromatic rings and aromatic ring assemblies, the halogenation is highly preferred so as to allow for increased charge dispersion that contributes along with steric bulk as independent features decreasing the likelihood of ligand abstraction by the strongly Lewis acidic metallocene cation formed in the catalyst activation. Additionally, halogenation inhibits reaction of the hafnium cation with any remaining carbon-hydrogen bonds of the aromatic rings, and perhalogenation precludes such potential undesirable reactions. Thus it is preferred that at least one third of hydrogen atoms on carbon atoms of the aryl ligands can be replaced by halogen atoms, and more preferred that the aryl ligands be perhalogenated. Fluorine is the most preferred halogen, perfluorinated aryl ligands are most preferred.
Means of preparing ionic catalyst systems comprising catalytically active cations of the hafnium compounds and suitable noncoordinating anions are conventionally known, see for example U.S. Pat. No. 5,198,401, WO 92/00333, WO 97/22639, and EP 0 612 768. Typically the methods comprise obtaining from commercial sources or synthesizing the selected transition metal compounds comprising an abstractable ligand, e.g., hydride, halide, alkyl, alkenyl or hydro-carbyl-silyl group, and contacting them with a noncoordinating anion source or suitable precursor compounds in a suitable solvent. The anion precursor compound abstracts a monoanionic ligand (or one monoanionic bond of bidentale alkenyl ligands) that completes the valency requirements of the preferred hafnium metallocene compounds. The abstraction leaves the hafnocenes in an essentially cationic state which is counterbalanced by the stable, compatible and bulky, noncoordinating anions according to the invention. Each of the documents of this paragraph are incorporated by reference for purposes of U.S. patent practice.
The noncoordinating anions are preferably introduced into the catalyst preparation step as ionic compounds having an essentially cationic complex which abstracts a non-cyclopentadienyl, labile ligand of the transition metal compounds which upon abstraction of the non-cyclopentadienyl ligand, leave as a by-product the noncoordinating anion portion. Hafnium compounds having labile hydride, alkyl, or silyl ligands on the metal center are highly preferred for the ionic catalyst systems of this invention since known in situ alkylation processes may result in competing reactions and interactions that tend to interfere with the overall polymerization efficiency under high temperature conditions in accordance with the preferred process embodiments of the invention.
Suitable cations for precursor compounds capable of providing the noncoordinating anions of the invention cocatalysts include those known in the art, in which the cation is a carbenium or an analog of carbenium. Such include the carbenium, oxonium or sulfonium cations of U.S. Pat. No. 5,387,568.
Examples of suitable anionic precursors include those comprising a stable carbenium ion, and a compatible non-coordinating anion. These include tropillium tetrakis(perfluoronaphthyl) or tetrakis(perfluoro-4-biphenyl) borate, triphenylmethylium tetrakis(perfluoronaphthyl) or tetrakis(perfluoro-4-biphenyl) borate, benzene(diazonium) tetrakis(perfluoronaphthyl) or tetrakis(perfluoro-4-biphenyl)borate, tropillium tetrakis(perfluoronaphthyl) or tetrakis(perfluoro-4-biphenyl)borate, triphenylmethylium tetrakis(perfluoronaphthyl) or tetrakis(perfluoro-4-biphenyl)borate, benzene (diazonium)tetrakis(perfluoronaphthyl) or tetrakis(perfluoro-4-biphenyl) borate, tropillium tetrakis(perfluoronaphthyl) or tetrakis(perfluoro-4-biphenyl)borate, triphenylmethylium tetrakis(perfluoronaphthyl) or tetrakis(perfluoro-4-biphenyl)borate, benzene (diazonium) tetrakis(perfluoronapthyl) or tetrakis(perfluoro-4-biphenyl)borate. The essentially structurally equivalent silylium borate or aluminate salts are similarly suitable.
The term xe2x80x9cscavengerxe2x80x9d as used in this application is used in its art-recognized sense of being sufficiently Lewis acidic to coordinate with polar contaminates and impurities that adventurously occur in the polymerization feedstreams or reaction medium. Such impurities can be inadvertently introduced with any of the polymerization reaction components, particularly with solvent, monomer and catalyst feed, and adversely affect catalyst activity and stability. In particular, for processes utilizing recycle streams of unconverted monomer for reprocessing, the necessity to use polar compounds as catalyst deactivators, or xe2x80x9ckillersxe2x80x9d, such as water or lower alcohols, effectively necessitates the use of scavengers, as does the natural occurrence of polar impurities in monomer feedstreams. It can result in decreasing or even elimination of catalytic activity, particularly when a metallocene cation-noncoordinating anion pair is the catalyst system. The polar impurities, or catalyst poisons include water, oxygen, metal impurities, etc. Preferably steps are taken before provision of such into the reaction vessel, for example by chemical treatment or careful separation techniques after or during the synthesis or preparation of the various components, but some minor amounts of scavenging compound will still normally be required in the polymerization process itself.
Typically the scavenging compound will be an organometallic compound such as the Group-13 organometallic compounds of U.S. Pat. No. 5,241,025, EP-A-0 426 638 and those of U.S. Pat. No. 5,767,208. Exemplary compounds include triethyl aluminum, triethyl borane, tri-isobutyl aluminum, methylalumoxane, isobutyl aluminumoxane, tri-n-hexyl aluminum and tri-n-octyl aluminum, those having bulky substituents covalently bound to the metal or metalloid center being preferred to minimize adverse interaction with the active catalyst. Addition of excess scavenger causes lower productivity, molecular weight and comonomer incorporation. The aluminum to hafnium molar ratios (Al:Hf) should accordingly be less than about 100:1, preferably less than about 75:1, more preferably less than about 50:1, and most preferably less than about 30:1. Molar ratios of less than 20:1 and less than 15:1 have been observed to be sufficient for the continuous processes described in this application.
The preferred scavenger is a long chain, linear tri-alkyl aluminum compound, and longer chains are preferred over shorter chains. See WO 97/22635 and U.S. Pat. No. 5,767,208 for further discussion, this document is incorporated by reference for purposes of U.S. patent practice. Non-limiting examples of effective long chain, linear tri-alkyl ligand-containing scavengers include those comprised in the group defined by the formula Mxe2x80x2Rxe2x80x2Rxe2x80x3Rxe2x80x2xe2x80x3, where Mxe2x80x2 is Al, and each of the R groups independently is a C4 or higher linear, branched or cyclic alkyl group, preferably C6 or higher, most preferably C8 or higher. The long chain, linear alkyl aluminums where each alkyl substituent was of a length of C8 or higher, preferably C9 and higher were observed to exhibit optimal performance, that defined as having the least deleterious effect when used at a level in excess of the optimum level as described in the following paragraph. Specifically included are tri-n-octyl aluminum, tri-n-decyl aluminum, tri-n-dodecyl aluminum, tri-n-hexadecyl aluminum, and the higher carbon number equivalents, e.g., (C20)3Al, including those with mixed ligation, and mixed scavenger compounds as well. The hydrolyzed derivatives of these alkyl-ligand containing organoaluminum compounds will additionally be suitable. Additionally, it will be apparent that those scavenging compounds comprising both long-chain, linear and bulky ligands or mixed linear ligands, each ligand as described above, will also be suitable, but perhaps less desirable due to more involved or expensive syntheses.
A preferred polymerization process is that designed or conducted such that the cocatalyst components, that is the transition metal compounds and the anion precursor compounds, are maintained separately until just prior to or during polymerization use in the chosen reactor or reactors. An example is the use of dual injection of each catalyst component directly into the reactor or the use of T- or multi-joint mixing chambers just prior to injection into the reactor. Additional optimization can be achieved when the scavenger compound is introduced into the reactor independently of the catalyst system or compounds, preferably after the activation of the hafnocenes with the anion precursor cocatalysts.
The process of the invention is applicable to high pressure homogeneous polymerization, preferably employing less than 30 wt % of solvent, which is substantially adiabatic and where the heat of polymerization is accommodated by a rise in temperature of the reactor contents instead of internal or external cooling. In this case, the contents consist principally of unreacted monomer. Such process may be performed, under single or dual phase homogeneous conditions at pressures from 250 to 3000 bar, preferably from 500 to 2500 bar, with or without unreactive diluents or solvents at temperatures generally above the melting point of the polymer being produced. Such processes are industrially known and may include the use of scavenger compounds and catalyst deactivation or killing steps, see for example U.S. Pat. No. 5,408,017, WO 95/07941, and WO 92/14766. Each of these documents and their U.S. counterparts are incorporated by reference for purposes of U.S. patent practice. Preferred catalyst deactivators, or killers, include high molecular weight, non-recyclable compounds, such as poly vinyl alcohol which exhibit the functional capacity to complex with the catalysts so as to deactivate them while not forming volatile polar by-products or residual unreacted compounds.
The process of the invention is also especially applicable to homogeneous solution polymerization which is also substantially adiabatic, that is to say the heat of polymerization is accommodated by a rise in temperature of the polymerization reactor contents, here principally solvent. This adiabatic process typically would have no internal cooling and suitably no external cooling. The reactor outlet stream removes the heat of polymerization from the reactor. The productivity of such adiabatic processes can be improved by cooling the inlet solvent and/or monomer stream(s) prior to introduction into the reactor to permit a greater polymerization exotherm. Thus the catalyst, cocatalyst and scavenger selections disclosed in this application can be advantageously practiced in a continuous, solution process operated at or above 140xc2x0 C., above 150xc2x0 C. or above 160xc2x0 C., up to about 225xc2x0 C. Most preferably the solution polymerization process for semi-crystalline polymers operated at a temperature from 140xc2x0 C.-220xc2x0 C. Typically this process is conducted in an inert hydrocarbon solvent, linear, cyclic or branched aliphatic, or aromatic, at a pressure of from 20 to 200 bar.
The xcex1-olefins suitable for use in the preparation of the ethylene copolymers, or for the polyethylene copolymers, are preferably C3 to C20 xcex1-olefins, but will include higher carbon number olefins such as polymerizable macromers having up to five hundred carbon atoms, or more. Illustrative non-limiting examples of such xcex1-olefins are one or more of propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, and 1-decene. Included in the term olefins for the purposes of describing effectively copolymerized monomers are the constrained-ring cyclic monoolefins such as cyclobutene, cyclopentene, norbornene, alkyl-substituted norbornes, alkenyl-substituted norbornes, and the higher carbon number cyclic olefins known in the art, see U.S. Pat. No. 5,635,573, incorporated herein by reference for purposes of U.S. patent practice, and known copolymerizable diolefins, e.g., 1,4-hexadiene, ethylidene-norbornene, and vinyl-norbornene. Vinyl aromatic monomers, e.g., styrene and alkyl-substituted styrene monomers are additionally suitable. The polyethylene copolymers can range from semicrystalline to substantially amorphous; and will typically have a substantially random arrangement of at least the ethylene and the olefin comonomers. As will also be apparent to those skilled in the art, the use of asymmetrically substituted hafnium compounds of the invention enable the preparation of syndiotactic polymers from prochiral olefins, e.g., like propylene. Processes for such will also benefit from the increased productivity and molecular weights described here for ethylene copolymers.
The effective Group 8-15 element cocatalyst complexes of the invention are, in a preferable embodiment, derived from an ionic salt, comprising a 4-coordinate, Group 10-14 element anionic complex, where Axe2x88x92 can be represented as:
[(M)Q1Q2 . . . Qi]xe2x88x92,
where M is one or more Group 10-15 metalloid or metal, preferably boron or aluminum, and either each Q ligand is effective for providing electronic or steric effects rendering [(Mxe2x80x2)Q1Q2 . . . Qn]xe2x88x92 suitable as a noncoordinating anion as that is understood in the art, or a sufficient number of Q are such that [(Mxe2x80x2)Q1Q2 . . . Qn]xe2x88x92 as a whole is an effective noncoordinating or weakly anion.
Additional suitable anions are known in the art and will be suitable for use with the metallocene catalysts of the invention. See U.S. Pat. No. 5,483,014, weakly coordinating anions from borane, carborane, borate, carborate, metalloborane, or metallocarborane complexes are described and exemplified. See also, the review articles by S. H. Strauss, xe2x80x9cThe Search for Larger and More Weakly Coordinating Anionsxe2x80x9d, Chem. Rev., 93, 927-942 (1993) and C. A. Red, xe2x80x9cCarboranes: A New Class of Weakly Coordinating Anions for Strong Electrophiles, Oxidants and Superacidsxe2x80x9d, Acc. Chem. Res., 31, 133-139 (1998).
In particular embodiments one Q group, or ligand, of the anionic complex may also be bonded to a metal/metalloid oxide support or polymeric support. See, for example, U.S. Pat. Nos. 5,427,991 and 5,939,347, each incorporated by reference for purposes of U.S. patent practice. Metal or metalloid oxide supports of the described bonding method for the invention include any metal/metalloid oxides, preferably those having surface hydroxyl groups exhibiting a pKa equal to or less than that observed for amorphous silica, i.e., pKa less than or equal to about 11. Accordingly, any of the conventionally known silica support materials that retain hydroxyl groups after dehydration treatment methods will be suitable in accordance with the invention. Because of availability, both of silica and silica containing metal oxide based supports, for example, silica-alumina, are preferred. Silica particles, gels, and glass beads are most typical.
Polymeric supports are preferably hydroxyl-functional-group-containing polymeric substrates, but functional groups may be any of the primary alkyl amines, secondary alkyl amines, and others, where the groups are structurally incorporated in a polymeric chain and capable of a acid-base reaction with the Lewis acid such that a ligand filling one coordination site of the Group 13 element is protonated and replaced by the polymer incorporated functionality. See, for example, the functional group containing polymers of U.S. Pat. No. 5,288,677, the functionalized polymers of U.S. Pat. No. 5,427,991 and the descriptions in copending applications U.S. Ser. No. 09/277,339, filed Mar. 26, 1999 now abandoned, and its equivalent PCT/99US/06135, and U.S. Ser. No. 09/092,752, filed Jun. 5, 1998 now U.S. Ser. No. 6,100,214, and its equivalent WO 98/55518. All are incorporated by reference for purposes of U.S. patent practice.
Other known methods for supporting catalyst systems comprising a noncoordinating anion cocatalyst will also be suitable as means for supporting the catalyst complexes of this invention. Thus, the catalyst complexes of the invention may also physically deposited on or affixed to a suitable support material. See, for example, the teachings of WO 91/09882, WO 93/11172, WO 96/35726 and U.S. Pat. Nos. 4,463,135, and 5,610,115.
When using the above catalysts, the catalyst system will generally employ one or more scavenging agents to remove polar impurities from the reaction environment and to increase catalyst activity. Any polymerization-reaction components, particularly solvents, monomers, and catalyst feeds, can inadvertently introduce impurities and adversely affect catalyst activity and stability. Impurities decrease or even eliminate catalytic activity, particularly with ionizing-anion-activated catalyst systems. Polar impurities, or catalyst poisons, include water, oxygen, metal impurities, etc. Preferably, these impurities are removed from or reduced in the reaction components before their addition to the reaction vessel. Impurities can be removed by chemically treating the components or by impurity separation steps. Such treatment or separation can occur during or after synthesis of the components. In any case, the polymerization process will normally employ minor amounts of scavenging agent. Typically, these scavengers will be organometallic such as the Group-13 compounds of U.S. Pat. Nos. 5,153,157, 5,241,025 and WO-A-91/09882, WO-A-94/03506, WO-A-93/14132, and that of WO 95/07941. Exemplary compounds include triethyl aluminum, triethyl borane, triisobutyl aluminum, methylalumoxane, and isobutyl alumoxane. Those compounds having bulky or C6-C20 linear hydrocarbyl substituents covalently bound to the metal or metalloid center are preferred because they coordinate to the active catalyst more weakly. Examples include triethylaluminum, but more preferably, bulky compounds such as triisobutylaluminum, triisoprenylaluminum, and long-chain, linear-alkyl-substituted aluminum compounds, such as tri-n-hexylaluminum, tri-n-octylaluminum, or tri-n-dodecylaluminum. When alumoxane is used as activator, any excess over that needed to activate the catalyst can act as a scavenger and additional organometallic scavengers may be unnecessary. Alumoxanes also may be used as scavengers with other activators, e.g., methylalumoxane and triisobutylalumoxane with boron-based activators. The scavenger amount is limited to that amount effective to enhance activity (and with that amount necessary for activation when used in a dual role) since excess amounts may act as catalyst poisons.
This invention""s catalyst system can polymerize those unsaturated monomers conventionally recognized as polymerizable using metallocenes. Typical conditions include solution, slurry, gas-phase, and high-pressure polymerization. The catalysts may be supported on inorganic oxide or polymeric supports and as such will be particularly useful in those operating modes employing fixed-bed, moving-bed, fluid-bed, slurry, or solution processes conducted in single, series, or parallel reactors. Invention cocatalysts may also function in catalyst pre-polymerization. WO 98/55518, incorporated by reference for purposes of U.S. patent practice, describes a preferred invention support method for gas-phase or slurry polymerization.
Alternative embodiments of this invention""s olefin polymerization methods employ the catalyst system in liquid phase (solution, slurry, suspension, bulk phase, or combinations thereof), in high-pressure liquid or supercritical fluid phase, or in gas phase. These processes may also be employed in singular, parallel, or series reactors. The liquid processes comprise contacting olefin monomers with the catalyst system described above in a suitable diluent or solvent and allowing those monomers to react long enough to produce the invention polymers. The term polymer encompasses both homo- and co-polymers. Both aliphatic and aromatic hydrocarbyl solvents are suitable; hexane is preferred. In bulk and slurry processes, the supported catalysts typically contact a liquid monomer slurry. Gas-phase processes typically use a supported catalyst and follow any manner suitable for ethylene polymerization. Illustrative examples may be found in U.S. Pat. Nos. 4,543,399, 4,588,790, 5,028,670, 5,382,638, 5,352,749, 5,408,017, 5,436,304, 5,453,471, and 5,463,999, 5,767,208 and WO 95/07942. Each is incorporated by reference for purposes of U.S. patent practice. The minimum polymerization reaction temperature is about 40xc2x0 C. Preferably, the minimum reaction temperature is about 60xc2x0 C. The temperature can go as high as about 250xc2x0 C., but preferably does not exceed 220xc2x0 C. The minimum reaction pressure is about 1 mm Hg, preferably about 0.1 bar, and most preferably 1.0 bar. The maximum pressure is less than or equal to about 2500 bar, preferably 1600 bar or lower, but most preferably 500 bar or less.
Invention catalysts can produce several types of linear polyethylene including high- and ultra-high-molecular-weight polyethylenes, including both homo- and copolymers with other alpha-olefin monomers or alpha-olefinic or non-conjugated diolefins, e.g. C3-C20 olefins, diolefins, or cyclic olefins. The polyethylenes are produced by adding ethylene, and optionally one or more other monomers, with invention activated catalysts that have been slurried with a solvent, such as hexane or toluene, to a reaction vessel under low pressure (typically  less than 50 bar), at a typical temperature of 40-250xc2x0 C. Cooling typically removes polymerization heat. Gas-phase polymerization can be conducted, for example, in a continuous fluid-bed, gas-phase reactor operated at a minimum of 2000 kPa and up to 3000 kPa. The minimum temperature is 60xc2x0 C.; the maximum temperature is 160xc2x0 C. The gas-phase reaction uses hydrogen as a reaction modifier at a concentration of no less than 100 PPM. The hydrogen gas concentration should not exceed 200 PPM. The reaction employs a C4-C8 comonomer feedstream and a C2 feedstream. The C4-C8 feedstream goes down to 0.5 mol %. It also may go up to 1.2 mol %. Finally, the C2 feedstream has a minimum concentration of 25 mol %. Its maximum concentration is 35 mol %. See, U.S. Pat. Nos. 4,543,399, 4,588,790, 5,028,670 and 5,405,922 and 5,462,999, which are incorporated by reference for purposes of U.S. patent practice.
High-molecular-weight, low-crystallinity, ethylene-xcex1-olefin elastomers (including ethylene-cyclic-olefin and ethylene-xcex1-olefin-diolefin elastomers) can be prepared using catalysts activated by inventions activators under traditional solution polymerization processes or by introducing ethylene gas into invention catalyst slurries with xcex1-olefin, cyclic olefin, or either or both mixed with other polymerizable and non-polymerizable diluents. Typical ethylene pressures range from about 10 to about 1000 psig (69-6895 kPa), and the diluent temperature typically remains between about 40 and about 160xc2x0 C. The process can occur in one or more stirred tank reactors, operated individually, in series, or in parallel. See the general disclosure of U.S. Pat. No. 5,001,205 for general process conditions. See also, international application WO 96/33227 and WO 97/22639. All documents are incorporated by reference for purposes of US patent practice.
Besides those specifically described above, other monomers may be polymerized using invention catalyst systems, for example, styrene, alkyl-substituted styrenes, isobutylene and other geminally disubstituted olefins, ethylidene norbornene, norbornadiene, dicyclopentadiene, and other olefinically-unsaturated monomers, including other cyclic olefins, such as cyclopentene, norbornene, alkyl-substituted norbornenes, and vinyl-group-containing, polar monomers capable of coordinating polymerization. See, for example, U.S. Pat. Nos. 5,635,573, 5,763,556, and WO 99/30822. Additionally, xcex1-olefin macromonomers of up to 1000 mer units or more may be copolymerized yielding branched olefin polymers. Additionally, oligomerization, dimerization, hydrogenation, olefin/carbon-monoxide copolymerization, hydroformulation, hydrosilation, hydroamination, and related catalytic reactions catalyzed by activated cation complexes can be activated with invention cocatalyst activators.
The invention activators can be used to activate catalysts as described above individually for coordination polymerization or can activate mixed catalysts for polymer blends. Adept monomers and catalyst selection yields polymer blends analogous to those using individual catalyst compositions. Polymers having increased MWD for improved processing and other traditional benefits available from polymers made with mixed catalyst systems can be achieved using invention cocatalysts.
Blended polymer formation can be achieved ex situ through mechanical blending or in situ through using mixed catalyst systems. It is generally believed that in situ blending provides a more homogeneous product and allows the blend to be produced in one step. In-situ blending with mixed catalyst systems involves combining more than one catalyst in the same reactor to simultaneously produce multiple, distinct polymer products. This method requires additional catalyst synthesis, and the various catalyst components must be matched for their activities, the polymer products they generate at specific conditions, and their response to changes in polymerization conditions. Invention cocatalyst activators can activate mixed catalyst systems.
Ethylene-xcex1-olefin (including ethylene-cyclic olefin and ethylene-xcex1-olefin-diolefin) elastomers of high molecular weight and low crystallinity can be prepared using the invention catalysts under traditional solution polymerization conditions or by introducing ethylene gas into a slurry of polymerization diluent and catalyst. The polymerization diluent contains xcex1-olefin monomers, cyclic olefin monomers, or their mixtures with other polymerizable and non-polymerizable monomers. In this case, polymerization reaction pressure varies, as well. The minimum pressure is 0.0013 bar; a pressure of at least 0.1 bar is more preferred. Most preferably, the reaction pressure is at least 1.0 bar. The maximum pressure is 2500 bar, with a pressure at most 1600 bar being preferred. The most preferred maximum pressure is 500 bar. Typical ethylene pressures will be between 10 and 1000 psig (69-6895 kPa). and the polymerization diluent temperature will typically be between xe2x88x9210 and 160xc2x0 C. The process can use a stirred-tank reactor, or more than one reactor operated in series or parallel. See the general disclosure of U.S. Pat. No. 5,001,205, which is incorporated by reference for its description of polymerization processes, ionic activators, and useful scavenging compounds.
Slurry or gas-phase reaction processes can use pre-polymerization of the supported invention catalyst to further control polymer particle morphology, as is known in the art. For example, such reaction can be accomplished by pre-polymerizing a C2-C6 xcex1-olefin for a limited time. Ethylene contacts the supported catalyst at between xe2x88x9215xc2x0 to 30xc2x0 C. and ethylene pressure of up to 250 psig (1724 kPa) for 75 min to obtain a polyethylene coating on the support (30,000-150,000 molecular weight). The above polymerization process can then use the pre-polymerized catalyst. Additionally, polymeric resins may be used as a support coating, typically by suspending a support in dissolved polystyrene resin or similar material followed by separation and drying.
The invention catalyst compositions can be used individually as described above or can be mixed with other known polymerization catalysts to prepare polymer blends. Monomer and catalyst selection allows polymer blend preparation under conditions analogous to those using individual catalysts. Polymers having increased MWD for improved processing and other traditional benefits available from polymers made with mixed catalyst systems can thus be achieved.

High activity carbenium-activated polymerization catalysts


A skating device having clips that allows a rider to position the sole of a shoe beneath to the lip so as to secure a rider""s shoe to the platform. The clip may be permanently or releasably secured and sized to fit conventional shoes. A professional version includes a specialty shoe that provides additional securement. Releasably secured clips may be concealed to allow the skateboard to be used in a conventional manner.

This invention relates generally to skateboards and more particularly to a skateboard attachment for gripping shoes.
Skateboarding includes a colorful history dating back to the 1950""s when the public began to equate skateboarding to the well established sport of surfing. Skateboarding was found as a substitute for surfing wherein an individual could improve balancing skills, a common element between the sports. Skateboarding was originally limited to streets and sidewalks and consisted of a board with clay wheels mounted to a bottom side. In the 1970""s, urethane wheels were introduced leading to a significant improvement by providing a stronger wheel that could handle slalom and downhill skateboarding.
To accommodate the vast improvement in skateboards, skate parks were built moving the skateboarder from a horizontal plane to vertical. Trick or freestyle skateboarding developed including numerous aerial moves named after the inventor xe2x80x9colliesxe2x80x9d where a rider taps on the tail of a board with one foot and sliding the other allows a rider to jump over immovable objects. Rollerblading has invaded most every skateboard park even though the sports are distinct. However, skateboarding remains safer than rollerblading and maintains a following who developed a xe2x80x9cstreetstylexe2x80x9d wherein technical tricks add to the enjoyment with or without the use of a skatepark.
The skateboard has evolved from a flat wood plank with clay wheels to polyurethane or wood platforms with frictionless bearings supporting polyurethane wheels.
U.S. Pat. No. 4,159,121 discloses a grip accessory for skateboards. This accessory consists of an elevated pedestal located along each end of a skateboard. The objective of the pedestal is to allow a rider to perform handstands as well as the shoes of a rider to fit under the pedestal. The pedestal is large and may act as an obstruction to the use of the board and safety of an individual. Placement of the foot beneath the pedestal inhibits quick release. Further, the size of the pedestals are so large that freestyle skateboarding is dictated by the pedestal configuration.
U.S. Pat. No. 5,641,172 discloses a skateboard having boots secured to the top portion of the skateboard platform. Although this attachment securely fastens a rider""s feet to the platform, this attachment limits use of the board to skateboard parks where no foot push is required. The rigid attachment is also considered unacceptable should the rider fall.
Thus, what is lacking in the art is a means for securing shoes to a skateboard that does not inhibit normal use or add to the bulk of a board.
Disclosed is a skating device formed from a conventional skateboard oblong platform. The platform is supported by a pair of roller assemblies mounted proximate to a tail end section and a second pair of roller assemblies mounted proximate to a front end section of the platform. In a preferred embodiment, the skating device includes the use of a clip secured to the top surface of the platform along the tail section and the front section. The clips each include a lip or projection that allows a rider to position the sole of a shoe beneath the lip so as to secure the rider""s shoe to the platform. The clip may be bolted, glued, or clamped allowing for the modification of existing skateboard to include use of the clip. Further, such installation methods can allow disassembly of the clips for use of the skateboard without the shoe locks if a single clip is desired or in need of replacement. Alternatively, the clips can be formed integral with the platform.
In an alternative embodiment, the clips can be raised for use and stored when not in use by lowering. In this embodiment, the clips can be lowered when not in use to a position flush with the upper surface of the platform. A rider can use the skateboard in its ordinary manner and then raise one or both of the clips to engage the soles of their shoes. The clips can further be removed without the need for tools.
In yet another embodiment, the clips can be formed to engage a speciality shoe wherein the clips operate in the same format as the previous embodiments, however, a modified shoe is adapted to provide superior attachment necessary for competitive freestyle boarding.
Thus, an objective of the invention is to disclose the use of hooks for securing the sole of a shoe, and thus the foot placed within the shoe, to the skateboard.
Still another objective of the invention is to disclose shoe attachments that are indiscrete and do not inhibit foot removal when necessary.
Another objective of the invention is to disclose the use of removable or retractable hooks that allow the use of a skateboard without surface protrusions.
Other objectives and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.


A plumbing part in the form of a water delivery device is comprised of a protective liner through which potable water can flow. The protective liner is in the form of one or more lengths of stainless steel tubing and is encased in a casting of a desired material, such as bronze or brass. Fittings required to attach the water delivery device to sinks, bathtubs or other water sources and to allow for insertion of various aerators and other flow devices are also encased in the casting. The various fittings are pre-assembled to the liner prior to casting to ensure a water-tight seal between the liner and the fittings prior to casting.

1. Field of the Invention
This invention relates generally to faucets and other water delivery devices, and more particularly to faucets and other water delivery devices in which a material is cast around a protective liner in order to form a water delivery device that meets current safety standards including, but not limited to the National Sanitation Foundation International (NSF) and the Canadian Standards Association (CSA).
2. Description of the Prior Art
In order to meet NSF an CSA or other state, national or international safety standards for water delivery devices, many faucets and other water delivery devices presently in the art are formed primarily from low-lead brass alloys and then plated with either chrome, brass, PDM or nickel type plating to achieve their desired finish. Other water delivery devices utilizes plastic coverings with snap-on liners with the covering provided to conceal the liner. Such liners are typically lined with copper tubing or molded plastic tubes. The liners and coverings of such plastic faucets are separately formed and assembled after individual formation of the various components. For example, the covering may include a top decorative portion for housing the liner. A separate bottom portion is then attached to the decorative portion, as by snapping or fastening, to enclose the liner within the device.
In many applications it would be desirable for water delivery devices to be formed from a stainless steel core or liner with other materials such as bronze, brass, ceramics, or plastics providing an exterior decorative shell. Stainless steel has been identified by most current safety standards as the preferred material for drinking water delivery devices. Unlike other materials commonly used in water delivery devices, stainless steel does not leach lead, arsenic or other potentially harmful or damaging particles into the water as the water flows through a stainless steel tube. Stainless steel, however, is very difficult to work with and form into desired shapes for decorative purposes and is more expensive than traditional faucet making materials. As such, the commercial use of stainless steel in decorative water delivery devices has been non-existent.
While stainless steel is the preferred material, it would also be desirable to be able to cast copper tubing or other lining materials directly into decorative, functional or other coverings formed from copper, bronze, pewter, ceramics, plastics or other materials. For example, it would be advantageous in the art to form a bronze water delivery with a stainless steel liner that prevents leaching of the bronze materials into the water. Thus, it would be advantageous to allow the flexibility of design by using moldable or castable materials to form the decorative portions of the water delivery device while lining the inside of the water delivery device to prevent leaching.
One such plumbing part that has been disclosed in the prior art is shown in U.S. Pat. No. 5,579,823 (the xe2x80x9c""823 patentxe2x80x9d) to Erwin F. Mikol and Andrew G. Pawlyszyn, now assigned to Moen Incorporated of North Olmsted, Ohio. The ""823 patent discloses a plumbing part made from a permanent core and a body cast around the core. The core is formed of a material which meets the requirements as to the permitted leachability of lead and/or other undesirable materials from the core into water flowing through it. The core material has a melting point preferably at least 200 degrees F. above that of the cast body. The core also has a coefficient of expansion which is equal to or least than that of the material forming the cast body.
The core of the ""823 patent is formed of #304 stainless steel and includes an upper stamping and a lower stamping. These two elements have outwardly extending flanges that are joining by welding, crimping or folding to thus join the upper and lower waterways in to a single unitary core. Thus, the core is formed from at least two separate parts that must be joined together to form the waterways of the desired core.
Thus, it would be advantageous to provide a plumbing part forming a water delivery device that utilizes a core that eliminates the concern of leaching of lead or other undesirable material from the water delivery device to the water, the core being formed from a length of tubing.
It would be a further advantage to provide a plumbing part forming a water delivery device which is relatively easy to manufacture and does not require any significant separate manufacture of the core prior to formation of the plumbing part.
It would be yet a further advantage of the present invention to provide a casting process which prevents inadvertent melting of the core during the formation process.
It would be still another advantage to provide a casting process which allows for use of materials with different coefficients of expansion without adversely effecting the finished plumbing part.
Accordingly, a plumbing part in the form of a water delivery device, in accordance with the principles of the present invention, is comprised of a protective liner through which potable water can flow. The protective liner is encased in a casting of a desired material, such as bronze or brass. Fittings required to attach the water delivery device to sinks, bathtubs or other water sources and to allow for insertion of various aerators and other flow devices are also encased in the casting. The various fittings are pre-assembled to the liner prior to casting to ensure a water-tight seal between the liner and the fittings prior to casting.
One method of forming a plumbing part in the form of a water delivery device in accordance with the present invention comprises providing a pattern of the desired exterior shape of the water delivery device. The pattern may be formed from an easily moldable material such as wood or plastic or some other formable material. The pattern is formed by forming a complete full-scale model of the desired exterior shape of the plumbing part. The model is then cut or otherwise divided in half along a longitudinal axis of the model. The pattern is formed by placing and attaching each half of the model inside a box-like structure. The pattern is then filled with casting sand. The sand is packed firmly around the pattern. Once the pattern is packed tightly with sand, the pattern and the casting sand are separated leaving a sand mold of one half of the water delivery device. The other half of the mold for the water delivery device is essentially a mirror image of the first and is formed by packing casting sand around the pattern for the second half in the same manner. Of course, those of skill in the art will appreciate that other methods of casting and casting materials may also be employed in accordance with the principles of the present invention. When combined, the two mold halves form a mold cavity in the shape of the entire model of the water delivery of the present invention.
The protective liner is formed into a shape that will position the liner generally along a central portion of the mold cavity of the mold. In one embodiment, the liner consists of a stainless steel tube, but it can also be made from other materials known in the art. The tube is thus bent into a particular shape matching the general curvature of the longitudinal length of the water deliver device so as to reside generally long a center-line of the water delivery device.
Because heat generated during casting may have an adverse effect on the liner, especially in areas where the casting material is to be relatively thick, a sand-like or other type of core material is applied to the exterior of the liner along its length where the casting material may pose a threat to the integrity of the liner. This is generally at the wider or more voluminous regions of the mold cavity. Thus, in order to maintain a relatively consistent casting thickness about the liner, the liner is packed or otherwise covered along certain portions thereof with a liner protection material (e.g., sand core). As such, a relatively regular annular space can be formed around the liner protection material along a complete length of the liner. It is noted that the liner protection material not only protects the liner from becoming damaged due to excessive heat during the casting process, but also reduces the amount of casting material needed to form the finished water delivery device in accordance with the principles of the present invention.
The annular space between the mold cavity and the liner protection material creates a space where the molten metal flows to form the exterior of the water delivery device and also defines the appropriate thickness of the casting portion of the water delivery device. The liner protection material helps to dissipate heat from the casting and prevents the heat from damaging the liner or otherwise allowing the casting material to melt holes in the liner. As previously discussed, the liner protection material also reduces the weight of the final casting and reduces the amount of casting material needed to complete the cast. It should be noted that, in some locations of the mold, the thickness of the casting material is thin enough that the liner itself can provide sufficient cooling during the casting process to prevent the casting material from melting or otherwise compromising the integrity of the liner. In such regions, the core material may not be necessary.
Such a core material, however, produces gas when exposed to the molten casting material. In order to help prevent such gases from escaping through the casting material resulting in holes blown through the side of the casting, a core vent is provided which is in fluid communication with the core material and the exterior of the mold. Such a core vent may be formed from such materials as braided metal, heat resistant fabrics, wax, perforated metal tubing, or other materials that can be placed in the mold and in fluid communication with the liner protection material to allow gases formed within the casting as a result of the heat of the casting material to flow into the core vent at points along its length and flow out of the mold to relieve gas pressure within the casting. In one embodiment, the core vent is formed from a braided cloth tube that is placed in the sand core. As gasses are generated by the core material, they naturally pass through the braided tube wall and into the interior of the core vent. By placing the interior passage of the core vent in communication with the outside of the mold, the gasses can flow out of the mold through a desired location in the casting rather than through the side of the casting producing an undesirable blow hole. In another embodiment, the core vent may be attached to a small piece of copper tubing that acts as a chimney.
The liner is placed in the casting mold in the mold cavity formed by the pattern of the water delivery device as previously discussed. The liner extends beyond both ends of the mold cavity in order to support the liner within the mold cavity. As desired for the type of water delivery device being formed, various fittings may be attached to the liner and thus placed in the mold. Such fittings may allow the finished water delivery device to be attached to a water source or other plumbing fixtures.
A flange is attached as by welding, soldering or other means of joining known in the art to a point proximate to the discharge opening of the liner.
In the situation where the fitting for attaching the inlet of the water delivery device is cast into the component, fixing both ends of the liner during a molten metal casting process may cause cracks in the casting as a result of the contraction of the casting during the cooling stages. That is, because the casting and liner will have different coefficients of thermal expansion due to their differences in material compositions and because the liner is significantly cooler than the molten casting material, the liner should be allowed to move relative to the casting metal as the casting metal contracts to prevent tears or damage to the casting material that may otherwise occur as a result of the shrinking of the casting material relative to the liner during the cooling process.
As such, a sleeve is attached to the inlet fitting as by welding or other means of attachment known in the art. The sleeve has an interior diameter that allows the liner to fit therein. After casting, as the casting cools and shrinks relative to the liner, the liner will protrude from the sleeve. The proximal or inlet end of the liner protruding from the exposed end of the sleeve can be cut and attached to the sleeve by welding, soldering or other means of joining known in the art which provides a water-tight seal between the sleeve and the liner.
Once all of the desired components are placed in the first half of the mold, the second half of the mold is fitted to the first half to effectively close the mold. Molten material is poured into the mold cavity to encase the stainless steel liner. Once the casting material has solidified, the mold is opened and the casting of the water delivery device is removed. The small molten metal resistant tube used to vent gases from the mold is twisted until loosened and then removed. Because the liner protection material turns into a particulate form after being exposed to the heat from the casting process, the core material can generally be shaken out through the hole left by the molten metal resistant tube. The excess liner at the outlet end of the water delivery device is cut off and a fitting is attached to the inlet of the liner. The outlet of the water delivery device is counterbored until the flange is reached. The opening created by the drill is then threaded as by tapping in order to allow an aerator to be attached.
Finally, the flashing formed between the mold halves is removed as by grinding or sanding and the exterior of the water delivery device is polished to the desired finish.

Water delivery device and method of forming same