United States Patent [191
`Royce
`
`lllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllll
`US005273758A
`5,273, 758
`[11] Patent Number:
`[45] Date of Patent: Dec. 28, 1993
`
`[54] DIRECI'LY COMPRESSIBLE
`POLYETHYLENE OXIDE VEHICLE FOR
`PREPARING THERAPEUTIC DOSAGE
`FORMS
`Inventor: Alan E. Royce, Effort, Pa.
`[75]
`[73] Assignee: Saudoz Ltd., Basel, Switzerland
`[21] Appl. No.: 868,073
`[22] Filed:
`Apr. 13, 1992
`
`Related U.S. Application Data
`[63] Continuation of Ser. No. 672,503, Mar. 18, 1991, aban-
`doned.
`Int. Cl.s ................................................ A61K 9/20
`[51]
`[52] u.s. Cl ..................................... 424/465; 424/464;
`424/486; 424/469
`[58] Field of Search ............... 424/464, 465, 469, 486,
`424/470
`
`[56]
`
`References Cited
`U.S. PATENT DOCUMENTS
`4,343,789 8/1982 Kawata et al ....................... 424/497
`4,996,047 2/1991 Kelleher et al ..................... 424/483
`Primary Examiner-Thurman K. Page
`Assistant Examiner-James M. Spear
`Attorney, Agent, or Firm-Robert S. Honor; Richard E.
`Vila; Diane E. Furman
`ABSTRACI'
`[57]
`Polyethylene oxide polymer is employed as a directly
`compressible binder matrix for therapeutically active
`dosage forms. Advantageously, the polyethylene oxide
`has an adjustable rate control effect on the release of
`medicament from the dosage form, enabling in particu-
`lar the preparation of sustained release dosage forms.
`
`26 Claims, 1 Drawing Sheet
`
`% Dissolved Clemastine Fumarate
`
`120~----------------------------------------~
`
`0
`
`2
`
`4
`
`10
`12
`8
`6
`Time, hours
`~ POLYOX N80 + POLYOX 303
`
`14
`
`16
`
`18
`
`KASHIV1027
`IPR of Patent No. 9,492,392
`
`

`

`-o-POLYOX N80 + POLYOX 303
`
`18
`
`16
`
`14
`
`Time, hours
`6
`12
`
`10
`
`8
`
`4
`
`2
`
`0
`
`120~--------------------------------~
`
`% Dissolved Clemastine Fumarate
`
`~ • 00. •
`
`FIG. 1
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`KASHIV1027
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`5,273,758
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`5
`
`1
`DIRECI'LY COMPRFSSIBLE POLYETHYLENE
`OXIDE VEHICLE FOR PREPARING
`THERAPEUTIC DOSAGE FORMS
`
`2
`heat-stable, have sufficient capacity for the active ingre-
`dient in the dosage form, accept colorants uniformly
`when necessary, and not interfere with biological avail-
`ability.
`Materials employed by the art which to varying de-
`grees fulfill the requirements of a direct compression
`This is a continuation of application Ser. No.
`07/672,503, field Mar. 18, 1991, now abandoned.
`vehicle include water soluble materials such as various
`forms oflactose (e.g., spray-dried lactose, Fast Flow®
`FIELD OF THE INVENTION
`lactose, anhydrous lactose), as well as sucrose, dextrose,
`This invention relates to compositions to be com- 10
`sorbitol, mannitol and maltodextrin, and relatively in-
`bined with a therapeutically active medicament and
`soluble materials such as microcrystalline cellulose
`formed into solid, shaped unit dosage forms. More par-
`(e.g., A vicel @),starch, dicalcium phosphate dihydrate,
`ticularly, the present invention relates to compositions
`and calcium carbonate.
`comprising a free-flowing directly compressible vehicle
`However, such materials, while often comprising a
`relatively large proportion by weight of the tableted
`which can be blended with a medicament, and to di- 15
`formulation in order to impart full advantage of their
`rectly compressed dosage forms prepared therefrom.
`compression properties, nevertheless in themselves are
`BACKGROUND OF THE INVENTION
`generally insufficient to regulate the rate of disintegra-
`tion of the dosage form or release of the medicament,
`In order to prepare solid, shaped dosage forms from
`fine particles or powders comprising therapeutic agents, 20
`and therefore must often be accompanied by various
`it has generally been necessary to process the powders
`additional excipient& having such a rate-control effect,
`in a manner to improve their flowability, cohesiveness
`the latter which (given practical limitations on the size
`and other characteristics which will enable the resulting
`of the dosage form) may be confmed to low concentra-
`material to be fabricated by conventional processes
`tions at which the rate control effect is not completely
`such as tableting, encapsulation, molding, etc. into a 25
`satisfactory.
`satisfactory unit form that can suitably deliver an agent
`It has therefore been an object to identify a directly
`into the environment of use.
`compressible vehicle which can exert a rate control
`Various processes have therefore been developed for
`function in the prepared dosage form.
`modifying starting powders or other particulate materi-
`In particular, it has been an object to prepare both
`als, in which typically the powders are gathered to- 30
`immediate and sustained release therapeutically active
`gether with a binder material into larger permanent
`dosage forms comprising such an excipient.
`free-flowing agglomerates or granules referred to col-
`SUMMARY OF THE INVENTION
`lectively as a "granulation." For example, solvent-
`It has now been found that directly compressed dos-
`assisted "wet" granulation processes are generally char-
`acterized in that the powders are combined with a 35 age forms may be prepared from compositions compris-
`binder material and moistened with water or an organic
`ing polyethylene oxide as a binder-matrix.
`solvent under conditions to result in formation of a wet
`The compositions and dosage forms of the invention
`granulated mass from which the solvent must then be
`comprise about 5 to about 99.99 wt.% of polyethylene
`evaporated. Such processes, while widely employed,
`oxide polymer, and a therapeutically active medicament
`have certain recognized limitations arising from the use 40 dispersed therein.
`The therapeutic medicament may comprise from
`when necessary of non-aqueous solvents which may be
`about 0.01 to about 95 wt.% of such compositions.
`environmentally deleterious, and furthermore may not
`be readily adaptable in connection with moisture or
`Advantageously, it has been found that the polyethyl-
`. heat sensitive medicaments. Alternatively, the known
`ene oxide can provide an adjustable rate controlling
`"dry granulation" processes, which can depend on 45 effect on the release of medicament from the dosage
`form, and that directly compressed dosage forms may
`fairly complicated milling schemes to produce a suitable
`granulation, also have acknowledged disadvantages.
`therefore be prepared which can dispense medicament
`A "direct compression" process has in limited cases
`at varying rates.
`provided a simpler and more economical means of pre-
`Further advantageously, the direct compression pro-
`paring compressed dosage forms.
`50 cess of the invention provides a therapeutically active
`In such a process, the therapeutically active ingredi-
`dosage form wherein the medicament is well dispersed,
`ent is combined with a binder-diluent or vehicle which
`has no loss of activity due to moisture or heat exposure
`itself is characterized in having the requisite properties
`such as may occur during a granulation process, and is
`for tableting, such as flowability, appropriate particle
`substantially free of solvent residues.
`size distribution, binding ability, acceptable bulk and tap 55
`BRIEF DESCRIPTION OF THE DRAWING
`density and dissolution properties, and the resulting
`blend can therefore be. "directly" provided to a die
`FIG 1 is a graph depicting the cumulative amount of
`cavity or mold for compaction, without prior granula-
`a medicament dispensed over a prolonged period of
`tion. See Shangraw, "Compressed Tablets by Direct
`time from dosage forms prepared according to the in-
`Compression," in Pharmaceutical Dosage Forms, 2d Ed., 60
`vention.
`1989, Vol. 1, pp. 195-246. The resulting compressed
`DETAILED DESCRIPTION OF THE
`dosage form often provides improved stability and dis-
`INVENTION
`sociation profiles, as well as batch-to-batch uniformity,
`relative to "wet" or "dry" granulated dosage forms.
`Polyethylene oxide is a nonionic homopolymer of the
`A suitable direct compression vehicle for a given 65
`formula -(-O-CH2-CH2-)-11, wherein n repre-
`application is preferably also tailored, for example, to be
`sents the average number of oxyethylene groups, n
`generally being from about 2,000 to about 100,000. It is
`compatible with the active ingredient, to resist physical
`or chemical change on aging, to be air, moisture and
`a water soluble resin which is available as a white pow-
`
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`5,273,758
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`4
`der in several grades which vary in viscosity profile
`the therapeutic medicament, as well as other optional
`when di.uolved in water, National Formulary XVII, pp.
`excipients, and (ii) providing the resulting mixture to a
`1963-1964 (1990) Molecular weights range from about
`compression machine, and applying sufficient pressure
`100,000 to about 6,000,000, corresponding to a viscosity
`to the composition to form a unitary dosage form.
`ranae of under about 200 cps for a S% aqueous solution s The medicament may be employed in powder, crys-
`of the lower molecular weight polymers to over about
`talline, or other form, and typically need not be com-
`6,200 cps for a 1% solution of the higher molecular
`pounded to an amorphous or other type aranuiated
`weipt polymers. Polyethylene oxide resins are com-
`form.
`mercially available under the tradename Polyox ®
`The polyethylene oxide and medicament and other
`from Union Carbide Corporation. The Polyox ® WSR 10 optional ingredients are dry blended, i.e. in the absence
`series corresponds to polymers having a broader distri-
`of added solvents or heat, to produce a free-flowing
`bution of molecular weight ranges than polymers in the
`material wherein the medicament is well dispened in
`WSR N series.
`the polyethylene binder-matrix.
`For example, Polyox ® WSR N80 has an average
`The mixture is then provided to, for example, a tablet-
`molecular weight of about 200,000, and a S% aqueous IS ing machine and a compression force of about O.S to 10
`solution thereof at 2S" C. has a viscosity on a Brookfield
`tons is applied.
`RVT, No. 1 spindle at SO rpm of about 65 to 115 cps,
`A tableted dosage form is therefore prepared, in
`and a pH of 8 to 10.
`which the medicament is generally evenly dispened
`Polyox ® WSR 303 has an average molecular weight
`throughout the polyethylene oxide binder, and which is
`of about 5,000,000 to 6,000,000, and a 1% aqueous solu- 20 free of solvent residues.
`tion thereof at 25" C. has a viscosity of 7,200 to 10,000
`As used herein, the term "tablet" refers to a com-
`cps on a Brookfield RVF, No.2 spindle at 2 rpm, and a
`pressed body which is composed of a plurality of dis-
`pH of 8 to 10.
`crete particles, and includes pills, lozenges, dragee
`Particle size distribution of the above-mentioned Po-
`cores, capsule slugs, molded forms, and the like.
`lyox ® resins is such that passage through a 10-mesh 2S
`The tableted dosage forms of the invention can pro-
`sieve is 100%, and through a 20-mesh sieve is about
`vide relatively immediate or more sustained release of
`96%. Other particle size distributions may also be useful
`the therapeutic medicament into the environment.
`in the invention.
`The expression "therapeutic medicament" or "drug"
`See Union Carbide Corp., POLYOX® WATER-
`shall include any physiologically or pharmacologically
`SOLUBLE RESIN Product Specifications (1988).
`30 active substance that produces a local or systemic ef-
`The use of a particular molecular weight polyethyl-
`fect(s) in animals, which include warm-blooded mam-
`ene oxide polymer as a binder material will depend on
`mals, humans, primates, etc.
`the desired disintegration or release rate characteristics
`The term "physiological" as used herein denotes the
`to be imparted to the prepared dosage form. In general,
`administration of a drug to effect normal levels and
`lower molecular weight polyethylene oxide polymers, 35 functions. The term "pharmacological" denotes varia-
`i.e. having MW of up to about 300,000, e.g., Polyox ®
`tions in response to the amount of drug administered to
`N80, may be selected to prepare tablets from which the
`the host. The devices have found a particular use as
`medicament is released within a relatively short time
`vehicles for various human and animal drugs, particu-
`period, i.e. immediate release tablets. Sustained release
`larly for the oral administration thereof, although for
`dosage forms may be prepared from the higher molecu- 40 other systems as well, including systems such as buccal,
`lar weight polymers, i.e. having MW higher than about
`implant, nose, artificial gland, rectum, cervical, intrau-
`300,000, especially about 5,000,000 (e.g., Polyox ®
`terine, occular, arterial, venous, ear and the like, may be
`303). It is contemplated that mixtures of varying molec-
`manufactured according to the process of the invention.
`The active drugs that can be delivered include inor-
`ular weight polymers may also be employed as a matrix
`system to obtain the desired tablet release properties, 45 ganic and organic drugs, without limitation, drugs that
`act on the central nervous system, cardiovascular drugs,
`and such mixtures may comprise respective amounts of
`the various polyethylene oxide polymers as shall be
`endocrine drugs, drugs for metabolic disorders, immu-
`within the skill of the worker in the art to ascertain to
`nologic drugs, and drugs for treatment of allergies and
`provide the appropriate release pattern.
`infectious diseases. More particularly, such drugs may
`Other optional components of the compositions of SO comprise depressants, hypnotics, sedatives, psychic
`the invention include various binders, disintegrants,
`energizers, tranquilizers, anti-hypertensives, anticon-
`diluents, etc., including cellulose ethers, such as hydrox-
`vulsants, muscle relaxants, antiparkinson agents, analge-
`ypropyl methylcellulose, and waxy substances, as well
`sics, anti-inflammatory, local anesthetics, muscle con-
`as minor amounts of various lubricants such as talc,
`tractants, anti-microbials, anti-malarials, hormonal
`colloidal silicon dioxide, stearic acid or metal stearates, 55 agents, contraceptives, sympathomimetics, diuretics,
`etc., and colorants, sweeteners, and the like.
`anti-parasitics, neoplastics, hypoglycemics, ophthal-
`The compositions of the invention comprise from
`mics, electrolytes, diagnostic agents, and the like.
`about 5 to 99.99 wt.%, and preferably 20 to 99.99 wt.%,
`Compositions according to the invention may be
`of free-flowing, directly compressible polyethylene
`prepared which comprise clemastine fumarate in free
`oxide binder material.
`60 base form, or in a pharmaceutically acceptable acid
`In one embodiment, the compositions consist essen-
`addition salt form. Clemastine fumarate, i.e., (1) Pyrrol-
`tially of the polyethylene oxide binder and the medica-
`idone, 2-[2-[1-(4-chlorophenyl)-1-phenylethoxy]ethyl]-
`(E)-2-butenedioate;
`(2)
`[R-(R • ,R *)]·,
`ment.
`1-methyl-,
`( + )-(2R)-2-[2-[[(R)-p-Chloro-a-methyl-a-phenylben-
`The dosage forms are prepared by a direct compres-
`sion process; that is, the process comprises, and in one 65 zyl]-oxy]-ethyl]-1-methylpyrrolidone fumarate, is a col-
`orless to faintly yellow, practically odorless, crystalline
`embodiment, consists essentially of, the steps of (i) dry
`blending particles comprising 5 to 99.99 wt.%, and
`powder. It belongs to the benzhydryl ether group of
`preferably 20 to 99.99 wt. %, of polyethylene oxide with
`antihistaminic compounds and has activity as an Ht·
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`KASHIV1027
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`5,273,758
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`6
`receptor antagonist (CAS 14976-57-9; CAS-15686-51-
`sion results are equivalent to those of the tablets pre-
`pared in (a). However, these higher molecular weight
`8).
`The following examples are merely intended to be
`polyethylene oxide-based tablets do not disintegrate
`illustrative of the invention and not limitative thereof.
`under standard testing procedures, indicating suitability
`s as a sustained release dosage form.
`Unless otherwise expressly indicated the chemical sub-
`stances used are in the National Formulary or the U.S.
`What is claimed is:
`1. A direct compression process for preparing a tab-
`Pharmacopeia.
`leted pharmaceutical dosage form consisting of the
`EXAMPLE 1
`steps of:
`a. blending a powder for crystalling therapeutic med-
`2.68 mg. clemastine fumarate, available from Sandoz 10
`Corp. under the tradename Tavist @, is combined with
`icament with a direct compression vehicle consist-
`ingessentiallyofpolyethyleneoxide,intheabsence
`177.32 mg. of polyethylene oxide having a molecular
`weight of (a) 200,000 (Polyox ® N80, Union Carbide)
`of added solvent or heat, to form a composition in
`or (b) 6,000,000 (Polyox ® 303, Union Carbide), and
`which the medicament in dispersed; and
`b. compresseing the resulting composition under suf-
`passed through a 60-mesh screen. The blended powders 15
`ficient pressure to form a tablet.
`are then compressed into tablets on a hand-operated
`Carver press. A compaction force of 1 ton is applied.
`2. A process according to claim 1 wherein the com-
`position comprises 0.01 to 95 wt.% medicament.
`Two tablets, prepared as in (a) and (b) above, are
`3. A process according to claim 2 wherein the com-
`subjected to dissolution studies according to the method
`described in U.S. Pharmacopoeia (1985) Vol. XXI, pp. 20 position comprises 5 to 99.99 wt.% polyethylene oxide.
`1243-1244.
`4. A process according to claim 1 wherein the poly-
`A multiple position dissolution stirrer such as that
`ethylene oxide is selected from polymers having an
`described at USP p. 1244, Apparatus 2, is employed,
`average molecular weight of up to about 300,000, poly-
`which is equipped with a Teflon paddle (20 rpm) in
`mers having an average molecular weight of about
`each of six vessels. A dissolution medium comprising 25 300,000 or greater, and mixtures thereof.
`900 mi. of deaerated and distilled water is maintained at
`5. A process according to claim 1 wherein the medi-
`37.±0.5" C. A tablet is sequentially dropped into each
`cament comprises from about O.Ql to about 95 wt.% of
`vessel. Stirring and timing (time zero) is commenced as
`the dosage form.
`the rJISt tablet hits the bottom of the vessel (under the
`6. A direct compression process for preparing a tab-
`30 leted pharmaceutical dosage form consisting essentially
`paddle).
`At regular intervals, aliquots of test solution are with-
`of the steps of:
`drawn from each of the vessels in the order in which the
`a. blending the medicament clemastine fumarate in
`tablets were originally dropped, using a stainless steel
`free base or pharmaceutically acceptable acid addi-
`cannula. The aliquots are withdrawn from a point mid-
`tion salt form with a direct compression vehicle
`way between the surface of the dissolution medium and 35
`comprising polyethylene oxide, in the absence of
`the top of the paddle and not less than 1 em. from each
`added solvent or heat, to form a composition in
`vessel wall.
`which the medicament is dispersed; and
`The amount of clemastine fumarate present in each of
`b. compressing the resulting composition under suffi-
`the vessels is calculated by reference to standard solu-
`cient pressure to form a tablet.
`tions using UV spectroscopy.
`7. A process according to claim 6 wherein the poly-
`the cumulative
`Accompanying FIG. 1 depicts
`ethylene oxide has the formula -(O-CH2-CH2)n-
`amount of medicament delivered by each tablet over an
`wherein n represents the average number of oxyethyl-
`extended period of time.
`ene groups, and n is 2,000 to 100,000.
`It will be seen that the tablets of the invention provide
`8. A process according to claim 6 wherein the poly-
`a gradual, controlled release of the medicament over an 45 ethylene oxide has an average molecular weight of
`extended period of time.
`100,000 to 6,000,000.
`9. A process according to claim 8 wherein the poly-
`EXAMPLE2
`ethylene oxide has a viscosity of under about 200 cps for
`Placebo tablets, each 4.9 mg., are prepared in a batch
`a 5% aqueous solution thereof.
`by mixing 98.7 mg of polyethylene oxide having a mo- 50
`10. A process according to claim 8 wherein the poly-
`lecular weight of (a) about 200,000 (Polyox ® N80) or
`ethylene oxide has a viscosity over about 6,200 cps for
`(b) about 6,000,000 (Polyox ® 303), with 11.0 mg. of
`a 1% aqueous solution thereof.
`hydroxypropyl methylcellulose (Pharmocoat 606) and
`11. A process according to claim 8 wherein the poly-
`0.27 mg of magnesium stearate, in a free-fall blender,
`ethylene oxide has a viscosity of 65 to 115 cps for a 5%
`aqueous solution thereof at 25• C. on a Brookfield RVT,
`and then compressing the blend on a high speed tablet 55
`press (Manesty, Betapress).
`No. 1 spindle at 50 rpm.
`For the tablets prepared according to (a) above, i.e.
`12. A process according to claim 8 wherein the poly-
`ethylene oxide has a viscosity of 7,200 to 10,000 cps for
`comprising polyethylene oxide having a molecular
`a 1% aqueous solution thereof at 25• C. on a Brookfield
`weight of about 200,000, a compressive strength (hard-
`RVF, No.2 spindle at 2 rpm.
`ness) and weight variation are obtained which indicate 60
`13. A process according to claim 6 wherein the com-
`that the flowability of the formulation is adequate for
`position comprises 0.01 to 95 wt.% medicament.
`the direct tableting process. The disintegration times for
`14. A process according to claim 6 wherein the com-
`the tablets using the USP method of Example 1 range
`position comprises 5 to 99.99 wt.% polyethylene oxide.
`from 30-45 min., indicating that relatively immediate
`15. A process according to claim 1 wherein the poly-
`release of a medicament can be effected by the tablets. 65
`For the tablets prepared according to (b) above, i.e.
`ethylene oxide has the formula -(O-CH2-CH2)n-
`comprising polyethylene oxide having a molecular
`wherein n represents the average number of oxyethyl-
`weight of about 6,000,000 (Polyox ® 303), the compres-
`ene groups, and n is 2,000 to 100,000.
`
`40
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`5,273,758
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`8
`7
`21. A process according to claim 1 wherein the poly-
`16. A process according to claim 1 wherein the poly-
`ethylene oxide has an average molecular weight of
`ethylene oxide has an average molecular weight of
`about 200,000.
`100,000 to 6,000,000.
`22. A process according to claim 1 wherein the poly-
`17. A process according to claim 16 wherein the
`polyethylene oxide has a viscosity of under about 200 S ethylene oxide has an average molecular weight of
`cps for a S% aqueous solution thereof.
`about S,OOO,OOO to 6,000,000.
`11. A process according to claim 16 wherein the
`23. A process according to claim 1 wherein the parti-
`polyethylene oxide has a viscosity over about 6,200 cps
`cles comprise about 20 to 99.99 wt.% polyethylene
`oxide.
`for a I% aqueous solution thereof.
`~..~ A
`d'
`laim 16 h
`·
`th
`to
`It A
`h
`.
`h
`-·
`laim 16
`process accor mg
`c
`w erem
`e
`din
`composition comprises O.Ql to 9S wt.% medicament.
`· pr~ accor
`w erem t e
`.g to. c
`polyethylene oxtd~ has a VlSCOSlty ?f 6S to 11 S cps for a
`25. A process according to claim l4 wherein the
`composition comprises s to 99.99 wt.% polyethylene
`S% aqueous so~ut10n thereof at 2S C. on a Brookfield
`RVT, No. 1 spmdle at SO rpm.
`oxide.
`26. A process according to claim 1 wherein the medi-
`20. A composition according to claim 16 wherein the IS
`polyethylene oxide has a viscosity of7,200 to 10,000 cps
`cament comprises clemastine fumarate in free base or
`for a 1% aqueous solution thereof at 25" C. on a Brook-
`pharmaceutically acceptable acid addition salt form.
`field RVF, No. 1 spindle at 2 rpm.
`•
`•
`•
`•
`•
`
`10
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
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`KASHIV1027
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`UNITED STATES PATENT AND TRADEMARK OFFICE
`CERTIFICATE OF CORRECTION
`5,273,758
`PATENTNO.
`December 28, 1993
`DATED
`INVENTOR(S) : Alan E. Royce
`It is certified that error appears in the above-identified patent and that said Letters Patent is hereby
`corrected as shown below:
`
`:
`
`Col. 6, 1. 10: delete "for" and insert therefor -- or --.
`
`Col. 6, 1. 10: delete "crystalling" and insert therefor
`crystalline --.
`
`Col. 6, 1. 14: delete "in" and insert therefor -- is --.
`
`Col. 6, 1. 15: delete "compresseing" and insert therefor
`compressing
`
`Signed and Sealed this
`Twentieth Day of September, 1994
`
`Attest:
`
`Attesting Officer
`
`Commissioner of Patents and Trademarks
`
`BRUCE LEHMAN
`
`KASHIV1027
`IPR of Patent No. 9,492,392
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