New! View global litigation for patent families

US3502466A - Manufacture of articles from powdered metals - Google Patents

Manufacture of articles from powdered metals Download PDF

Info

Publication number
US3502466A
US3502466A US3502466DA US3502466A US 3502466 A US3502466 A US 3502466A US 3502466D A US3502466D A US 3502466DA US 3502466 A US3502466 A US 3502466A
Authority
US
Grant status
Grant
Patent type
Prior art keywords
putty
die
coping
formed
metal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
Inventor
Ronald C Vickery
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ceramco Ind Products Corp
Original Assignee
Ceramco Ind Products Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Grant date

Links

Images

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER
    • B22F1/00Special treatment of metallic powder, e.g. to facilitate working, to improve properties; Metallic powders per se, e.g. mixtures of particles of different composition
    • B22F1/0003Metallic powders per se; Mixtures of metallic powders; Metallic powders mixed with a lubricating or binding agent
    • B22F1/0059Metallic powders mixed with a lubricating or binding agent or organic material
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61CDENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
    • A61C13/00Dental prostheses; Making same
    • A61C13/08Artificial teeth; Making same
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61CDENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
    • A61C5/00Filling or capping teeth
    • A61C5/70Tooth crowns; Making thereof
    • A61C5/77Methods or devices for making crowns
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL, OR TOILET PURPOSES
    • A61K6/00Preparations for dentistry
    • A61K6/02Use of preparations for artificial teeth, for filling or for capping teeth
    • A61K6/04Use of metals or alloys
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER
    • B22F3/00Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/10Sintering only
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49567Dental appliance making
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49588Jewelry or locket making
    • Y10T29/4959Human adornment device making

Description

March 24,1970 R. c. VICKERY 3,502,466

MANUFACTURE OF ARTICLES FROM POWDERED METALS Filed Feb. 9, 1968 Flt: 4-

TTE= 5.

- lNl/EN TOR. RONALD C. V/CKERY Attorneys nited States 3,502,466 MANUFACTURE OF ARTICLES FROM POWDERED METALS Ronald C. Vickery, Northport, N.Y., assignor, by mesne assignments, to Ceramco Industrial Products Corp., Long Island City, N.Y., a corporation of New York Filed Feb. 9, 1968, Ser. No. 704,400

Int. Cl. B22f 7/00 US. Cl. 75-208 10 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION Although not limited thereto, the present invention is particularly adapted for use in the manufacture of articles formed from precious metals such as jewelry and metallic dental prostheses. Metallic dental prostheses such as crowns, inlays, partial plates and the like are conventionally prepared by one or more variations of the lost wax process. In this process, a wax pattern is first made of the article; the wax pattern is provided with sprues, vents and a pouring cup and invested in a suitable refractory mold; the wax is eliminated from the mold by heating at a relatively low temperature; the mold is fired; and molten metal is then cast into the heated mold.

While such casting techniques have been known and employed for many years, the individual steps of the overall technique are tedious and excess metal has to be cast for the formation of sprues, risers, vents, buttons and the like. Furthermore, the system of casting, whether from an electric or flame heated furnace, tends toward the loss of higher vapor pressure alloying elements, and results in variations in casting quality and porosity due to gases evolved during casting.

In the case of a dental bridge, it is often necessary to cast a coping for each individual tooth and thereafter solder these individual copings together. This is a tedious and time-consuming process and requires a high degree of skill. For that matter, it is probably the most difficult part of the fabrication of a dental bridge from cast metallic components.

SUMMARY OF THE INVENTION As an overall object, the present invention provides a method and material for forming sintered metal articles from powdered metals without the necessity for pressing the powdered metal into a mold prior to sintering as is conventional.

More specifically, an object of the invention is to provide a sintering process for the formation of metallic articles wherein the powdered metal is first mixed with a binder to form a putty or paste, the paste thereafter formed into the desired shape, and the shape then heated whereby the binder is driven off and the powdered metal sintered into a compact mass.

In accordance with the invention, a putty-like mass is provided comprising very finely divided metallic particles mixed with a binder which, while permitting a degree of fluidity, also is capable of providing strength of construction up to the point at which sintering and bonding of the particles takes place. This metal putty may be formed atent 3,502,466 Patented Mar. 24, 1970 into a solid mass, or hollow articles may be formed by implacing the putty on a refractory die, suitably treated to provide separation of the final metal construction. The putty is carved or sculptured with an appropriate instrument to the required contours and is first gently dried and then placed in a furnace at low temperature. During this step of the process, the binder is driven off. The temperature of the furnace is then raised to the point of sintering and bonding of the metallic particles. After a brief sojourn at this temperature, the system is cooled and a metal structure is provided capable of being burnished, polished or otherwise mechanically finished and, in the case of dental prostheses, capable of being surmounted by porcelain, plastic or the like.

In any dental prosthesis, it is necessary to have as good a fit as possible to the underlying tooth and gum structure. In the sintering process, the shape formed by carving or sculpturing will tend to shrink to some degree since, among other reasons, the binder is expelled from the putty from which the sintered product is formed. Therefore, in accordance with another aspect of the invention, the shape is first formed on a refractory die which is an exact replica of a prepared tooth, then sintered, and thereafter removed from the furnace and cooled. The shape is then removed from the refractory die and a shoulder or collar of the paste is formed around the base of the die. The previously-sintered shape is again placed over the die and forced downwardly such that its lower periphery is pressed into the soft putty collar. Thereafter, the article is again sintered; and very little shrinkage takes place, insuring a good fit to the underlying tooth structure.

The above and other objects and features of the invention will become apparent from the following detailed description taken in connection with the accompanying drawings which form a part of this specification, and in which:

FIGURE 1 is an isometric view of a die upon which a gold coping for dental prosthesis is built up, together with a platen on which the metallic putty of the inven tion is disposed and a spatula which is used to build up the putty on the die;

FIG. 2 shows the manner in which the putty is built up on the die;

FIG. 3 shows the completed article built up from the putty of the invention prior to firing;

FIG. 4 shows the completed, sintered coping as it is removed from the die; and

FIG. 5 shows the manner in which a shoulder is added to the previously-formed coping to accommodate for possible shrinkage occurring during sintering.

FORMATION OF THE METAL POWDER PUTTY In the practice of the invention, a metallic putty is initially formed comprising metal particles mixed with a suitable binder. The physical requirements for a usable system are that the metal particles should be in spherical powder form with individual particles no larger than about 25 microns in diameter and preferably in the range of about 2 to 15 microns. This size is necessary to insure adequate particle interaction (i.e'., fusing during sintering) at temperatures significantly below the intrinsic melting point of the metal and provide maximum density. The particles should be spherical in shape so as to provide for (a) easy application of the putty to a die (i.e., spheres will roll on each other rather than pack into an immobile mass), and (b) minimal surface area per particle so as to minimize firing shrinkage.

These metal spheres are suspended in a binder or medium permitting maximum metal concentration together with ease of cohesion, this cohesion persisting to temperatures at which sintering or alloying occurs of the metal spheres. Clearly, the smaller the particles, the lower will be the temperature of cohesion through sintering. If necessary, the suspending medium can be bi-phase or polyphase. That is, it can be a liquid menstruum carrying a low temperature binder of sufiicient strength to permit shape retention up to the point of particle cohesion by sintering, but thereafter all medium and binder must be volatile and eliminated by heating.

The binder must be an adhesive suspended within a solvent. Binders which have been found to be suitable include, without limitation, ammonium caseinate, ammonium stearate, pectin, hexamine, ethyl cellulose, anthracene, triacetyl starch, dulcin, carbazole and tetraphenyl ethylene. Other binders may also be used, the important consideration being that the binder must retain its binding properties up to about 400 F. while at the same time must be volatile such that it can be eliminated by heating. The solvents with which the binder is mixed include, again without limitation, propylene glycol, water, eugenol, light paraflin oil, butyl acetate, butyl benzoate, diacetone alcohol, and dibutyl phthalate. Again, the solvent must be compatible with the binder and at the same time must be volatile such that it can be driven off by heating.

FABRICATION OF THE ARTICLE FROM PUTTY The putty thus formed is identified by the reference numeral 10 in FIG. 1 and is conveniently disposed on a disc 12. In the example of the invention given in the drawings, the putty preferably comprises powdered gold spheres or alloys of gold in an appropriate binder, which putty is used to form a coping for a dental crown. Such a coping is then coated on its outer surface with porcelain, the gold supplying strength and accurate fit and the porcelain providing esthetics and function.

In forming a jacket crown, a thickness of the tooth structure is first removed by a dentist. Thereafter, a wax, rubber or the like impression is made of the tooth so prepared. Poured into this impression is a castable refractory die composition upon which a gold coping can be formed. As was mentioned above, this gold coping is ordinarily formed by means of the lost wax process which requires investing a wax model, the use of sprues and the like. After the coping is thus formed, it is completely or partially coated with porcelain.

In FIG. 1 the die, comprising a model of the tooth which was ground down by the dentist, is identified by the reference numeral 14. A portion of the gold putty It) is placed upon the end of a spatula 16 and applied around the die 14 as shown in FIG. 2 by means of the spatula 16. In this process, the coping is built up and carved from the putty manually, the lower portion of the coping being identified by the reference numeral 18A in FIG. 2. This build up of the coping with the gold putty 10 continues until the coping is completed as shown in FIG. 3 where the coping is identified by the reference numeral 18B. It should be pointed out that prior to the application of the putty to the die 14, the die is first painted with a separator which preferably comprises a dispersion of mica or other alumino-silicate in nitrocellulose solution. This separator enables easy separation of the completed coping from the die 14 after sintering.

SINTERING OF THE FORMED PUTTY ARTICLE After the putty is thus built up into the coping 188 as shown in FIG. 3, the entire assembly is pre-fired at a temperature of about 800 F. to 1200 F. for about five minutes. In this process, the binder and its solvent are driven off; however the putty, due possibly to partial sintering, retains its shape. Thereafter, the temperature is increased up to about 1860 F. at a rate of about 100 F. per minute. It is necessary to hold the temperature at the sintering point of 1860 F. for only a few minutes. Thereafter, the die 14 and sintered coping may be removed from the furnace. After cooling, the completed, sintered coping 18C shown in FIG. 4 may be pulled from the die 14.

During the sintering process, a certain amount of shrinkage will occur; and this may cause the lower edge of the completed coping 20 to move upwardly away from the die. This is undesirable for the reason that it is of utmost importance that the coping and completed crown fit closely to the gum or other substrate over which it is placed. Accordingly, if such shrinkage occurs, it is possible to form a collar from the putty 10 around the base of the die 14. This is shown in FIG. 5 where the collar formed from putty is identified by the reference numeral 22. After the collar 22 is thus formed, the perviously sintered coping 18C may again be placed over the die 14 and forced down into snug abutting relationship With the collar 22. The sintering process is then repeated; and the collar fuses completely to the previously formed coping 18C. Any shrinkage in the collar 22 is of a minor nature only and, consequently, a good fit is assured. If desired or necessary, a portion of the previously formed coping 18C may be removed from its bottom peripheral portion 20 prior to the coping being inserted over the die 14 and into engagement with the putty collar 22.

The thus-formed article is, for the most part, nonporous. However, to insure that voids are eliminated, it is possible to prepare a precious metal putty, for example, by admixture of the metal powders with a resinous solution of a noble metal. For example, gold, platinum or rhodium powders may be jointly prepared as a putty with a silver resinate containing 30%-40% silver. The silver resinate portion acts as a binder and, on ignition, leaves the silver content to alloy with the other precious metals and seal off all voids.

Alternatively, the precious metal putty prepared as originally described above can be applied to the die, carved and fired and then have applied to it again a precious metal resinate solution which will seep into and fill pores by capillary action. The system being again dried and fired, the residual precious metal from the resinate will fill out and seal off any voids.

Again, voids in the structure may be eliminated by the mechanism of liquid-phase sintering, i.e., the metal powder mixture com osition is adjusted so that two or more ingredients will interact to yield a relatively low melting point eutectic liquid which will wet the other metal particles and flow, by capillarity, into voids in the sintered structure. Thereafter, on further heating, this eutectic liquid will, by volume diffusion, form, with the mass of metal particles, an alloy of higher melting point.

Examples As an example of the invention, 99.98% pure gold was prepared in spherical form and screened to give particles which were smaller in size than 20 microns in diameter. Fifty grams of this powder were formed into a putty-like mass by blending with 3 cubic centimeters of 12% ammonium caseinate in propylene glycol. A ceramic die such as die 14, coated with a refractory separating medium, was taken and the gold putty, prepared as indicated, was applied to the coated die and shaped to conform to a normal coping configuration. The whole system was dried gently in front of a furnace at about 600 F. and then inserted into the furnace. The temperature of the furnace was raised to l860 F. at about 75 per minute. After removal from the furnace and cooling, the fired gold shape was seen to conform closely to the die structure and could be easily detached and employed for construction of a porcelain or plastic on gold prosthesis.

As another example, an alloy of gold, platinum, palladium and silver was prepared in spehical powder form, the particles being of a diameter less than 20 microns. Fifty grams of this powder were then formed into a putty by blending with 3 cubic centimeters of ethyl cellulose in dibutyl phthalate. The procedure of constructing a coping was again followed. That is, a ceramic die, coated with a refractory separating medium, was taken and the putty applied to the coated die and shaped to conform to a normal coping configuration. The die with the putty coping applied was then preheated at about 900 F. for five minutes and then inserted into the furnace where the temperature was raised to 1860 F. at a rate of about 100 F. per minute. The resulting coping had applied thereto porcelain of a matching coefficient of thermal expansion and fired to the gold alloy structure to yield a porcelain on gold prosthesis.

As another example, the die for a gold coping prepared as in the first example above had applied around the base thereof a collar of the previously-formed putty. Thereafter, the previously-sintered coping was reapplied over the die and forced down onto the soft mass forming the collar. Any excess material was scraped off and the preheating and sintering process repeated as above. At this time other geometrical requirements of the coping were added, i.e., lingual collars and connection uprights as is necessary in the case of splinted units, that is to say, multiple units which will be attached together. Upon removal from the furnace and cooling, the putty collar was found to have fused to the bottom of the original coping and fit exactly to the substrate die.

As another example, a mixture was formed of gold, platinum, palladium and silver powders of less than micron size, and sintered to a reasonably coherent (70% theoretical density) mass at 1860 F. Added to this powder mixture was 2%5% of silicon or aluminum powder (less than 20 micron size). On heating, as before described, the silicon or aluminum particles initially interacted with the gold particles (which were in the majority) to form a low melting point eutectic (5% Si-95% Au has Tm=400 C.). This fluid eutectic rapidly permeates the sintered body and inundates voids and, as the temperature and time of heating are increased, further reacts with the excess gold or other metal by volume diffusion to give a higher melting point alloy.

Or again, mixtures of titanium and nickel powders can be prepared in ratio close to 4:1. On firing, these first form a eutectic containing 75% Ti and Ni, melting at 950 C. (1740 R), which fills voids in the structure and then difiuses into the remaining particles to give a higher melting point alloy. In sintering such a system it is, of course, necessary to fire under vacuum to avoid oxidation of the alloy. This is done routinely, this liquid phase sintering approach having been employed to prepare structures from mixtures of the following powders:

Ti-Ni (4:1, the 3:1 eutectic melts at 950 C.)

Au-Pd-Pt-Ag-Si (80:5:5 :528, the 5% Si-Au eutectic melts at 400 C.)

Fe-Ni-Bi-Sn (:60:6z4, the Bi-Sn eutectic melts at In-Ni (3 :7, the 40% In eutectic melts at 915 C.)

Fe-Cr-In-Sn (80:20:3z3, the 52% In-Sn eutectic melts at Ag-Au-Si ::8, the 5% Si eutectic melts at 400 C.)

Ag-Au-Al (50:45:53, the 5% Si-Au eutectic melts at It will be apparent that while the above examples relate to the formation of a coping used in a dental crown, the putty of the invention can also be used to form unitary bridge structures or inlay prostheses for both posterior and anterior teeth. Furthermore, the invention is clearly not limited to dental prostheses as such. For example, it can be used to form any metallic article; however it is praticularly adapted for use in forming one-of-a-kind articles such as, for example, jewelry or other items formed from precious metals. There is, however, no intention to limit the invention to precious metals as such since other non-precious metals can be formed into a powder and mixed with a binder to form a putty which can be carved into the desired shape and then sintered. Finally, the invention is not constrained to the use of putties of metal powders as such. These may be replaced by oxides, hydroxides, organic metallic compounds and the like which may be reduced to the corresponding metal upon firing.

Although the invention has been shown in connection with certain specific embodiments, it will be readily apparent to those skilled in the art that various changes can be made to suit requirements without departing from the spirit and scope of the invention.

I claim as my invention:

1. In the method for forming a sintered metallic article, the steps of mixing finely divided metallic particles of about 2 to 25 microns in average diameter with a binder to form a putty, the binder being such that it will volatilize and purge itself from the putty at a temperature lower than the desired sintering temperature of said metallic particles, forming said putty into a desired shape, heating said formed shape to initially burn off said binder, and thereafter continuing heating of said formed shape to sinter said metallic particles into a fused, essentially non-porous compact mass.

2. The method of claim 1 wherein said finely divided particles comprise particles of a precious metal.

3. The method of claim 1 wherein said metallic particles are formed from two different metals to form an alloy upon sintering.

4. The method of claim 1 wherein said putty is formed into a desired shape by carving.

5. The method of claim 1 wherein said binder comprises a mixture of at least two components, one of said components being selected from the group consisting of ammonium caseinate, ammonium stearate, pectin, hexamine, ethyl cellulose, anthracene, triacetyl starch, dulcin, carbazole and tetraphenyl ethylene, and the other of said components being selected from the group consisting of propylene glycol, water, eugenol, light parafiin oil, butyl acetate, butyl benzoate, diacetone alcohol and dibutyl phthalate.

6. The method of claim 1 wherein said putty is applied by carving over a ceramic die.

7. The method of claim 1 wherein said putty is carved over a ceramic die to form a dental prosthesis.

8. The method of claim 1 wherein heating of the formed shape takes place in two steps, the first step being at a substantially constant temperature below the sintering temperature of said metallic particles, and the second step comprising gradually heating said putty in the desired shape after said binder has been burned oft up to the desired sintering temperature of the metallic particles.

9. The method of claim 1 including the step of applying to the sintered shape a precious metal resina te solution which will seep into and fill pores in the sintered shape by capillary action.

10. The method of claim 1 wherein said metallic particles are formed from a plurality of different metals, at least two of which interact upon heating to form a eutectic liquid which will wet the other metallic particles and fiow, by capillarity, into any voids in the sintered mass.

References Cited UNITED STATES PATENTS 2,744,011 5/1956 Samuel 75222 X 2,792,302 5/1957 Mott 75222 X 3,050,386 8/1962 von Dohren 75222 X 3,052,967 9/1962 Fischer 75222 X 3,171,195 3/1965 Darling 29-1606 X 3,184,840 5/1965 Byrne 29160.6' X

(Other references on following page) 7 8 UNITED sTATEs PATENTS CARL D. QUARFORTH, Primary Examiner 6/1966 Bull 75-208 X A. J. ST'EINER, Assistant Examiner 8/1966 Duddy 75 222 11/1966 Blaha 75-222 10/1967 Ang 75-226 X 5 29160.6; 75-200, 211, 214 12/1967 Duddy 75 222 X

US3502466A 1969-04-22 1968-02-09 Manufacture of articles from powdered metals Expired - Lifetime US3502466A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
FR6912611A FR2036946B1 (en) 1969-04-22 1969-04-22

Publications (1)

Publication Number Publication Date
US3502466A true US3502466A (en) 1970-03-24

Family

ID=9032839

Family Applications (1)

Application Number Title Priority Date Filing Date
US3502466A Expired - Lifetime US3502466A (en) 1969-04-22 1968-02-09 Manufacture of articles from powdered metals

Country Status (4)

Country Link
US (1) US3502466A (en)
DE (1) DE1915977B2 (en)
FR (1) FR2036946B1 (en)
GB (1) GB1271157A (en)

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3862840A (en) * 1972-12-20 1975-01-28 Airco Inc Process for manufacture of hard and non-deformable alloys without compacting by sintering in the solid-liquid phase
US4491559A (en) * 1979-12-31 1985-01-01 Kennametal Inc. Flowable composition adapted for sintering and method of making
US4742861A (en) * 1985-04-15 1988-05-10 Itzhak Shoher Method and material for dental structures
US4814008A (en) * 1985-04-15 1989-03-21 Itzhak Shoher Dental material
US4937928A (en) * 1987-10-07 1990-07-03 Elephant Edelmetaal B.V. Method of making a dental crown for a dental preparation by means of a CAD-CAM system
USRE33371E (en) * 1985-04-15 1990-10-09 Method and material for dental structures
US4997699A (en) * 1985-04-15 1991-03-05 Itzhak Shoher Material for reinforcing dental structures
EP0416398A1 (en) * 1989-08-24 1991-03-13 Asahi Kogaku Kogyo Kabushiki Kaisha Paste for bonding granular bone prosthesis and bone prosthesis using same
EP0499721A1 (en) * 1991-02-21 1992-08-26 Elephant Edelmetaal B.V. A powder of dental metal, a process for the preparation thereof, a process for the manufacture of a substructure for a dental restoration and a process for the manufacture of a dental restoration
US5234343A (en) * 1991-12-02 1993-08-10 Itzhak Shoher Moldable dental material and method
US5332622A (en) * 1993-01-19 1994-07-26 Itzhak Shoher Moldable dental material for forming or repairing a dental restoration
US5336091A (en) * 1991-12-02 1994-08-09 Itzhak Shoher Moldable dental material and method
USRE35367E (en) * 1985-04-15 1996-10-29 Shoher; Itzhak Material for reinforcing dental structures
US5730600A (en) * 1993-01-19 1998-03-24 Shoher; Itzhak Method for forming a dental restoration
WO2002007680A2 (en) 2000-07-21 2002-01-31 Jeneric/Pentron Incorporated Molds for the manufacture of a dental restoration
US6613273B2 (en) 2000-01-10 2003-09-02 Jeneric/Pentron Incorporated Method for the manufacture of dental restorations
US6627248B1 (en) 2000-11-10 2003-09-30 Jeneric/Pentron Incorporated Metallization of ceramic restorations
US20030205107A1 (en) * 2000-11-14 2003-11-06 Board Of Trustees Of University Of Illinois Colored metal clay and colored metals
US6667112B2 (en) 2000-01-10 2003-12-23 Pentron Laboratory Technologies, Llc Method for the manufacture of dental restorations
US20040109783A1 (en) * 2000-01-10 2004-06-10 Arun Prasad Method for the manufacture of dental restorations
US20050115466A1 (en) * 2001-09-28 2005-06-02 Mitsubishi Materials Corporation Silver powder for silver clay and silver clay comprising the silver powder
US20070113707A1 (en) * 2004-05-14 2007-05-24 Cascone Paul J Dental prosthesis method and alloys
US20120123577A1 (en) * 1995-06-02 2012-05-17 Ormco Corporation Custom orthodontic appliance forming method and apparatus

Families Citing this family (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4828495A (en) * 1984-04-03 1989-05-09 Denpac Corp. Sintered alloy dental prosthetic devices and method
DE3532331C2 (en) * 1985-09-11 1991-10-31 Degussa Ag, 6000 Frankfurt, De
DE3811628C2 (en) * 1988-04-07 1990-01-11 Heraeus Edelmetalle Gmbh, 6450 Hanau, De
DE3841902C1 (en) * 1988-12-13 1989-11-02 Degussa Ag, 6000 Frankfurt, De
NL9001516A (en) * 1990-07-03 1992-02-03 Elephant Edelmetaal Bv A method of manufacturing a substructure for a dental restoration such as a crown or a bridge, and a method for producing such a dental restoration.
EP0523019A3 (en) * 1991-07-12 1994-03-23 Nobil Metal Srl
DE4343420A1 (en) * 1993-12-18 1995-06-29 Sinterstahl Gmbh A process for producing moldings sintermetallischer
EP0709473B1 (en) * 1994-10-24 1998-12-23 Ivoclar Ag Process of making metal castings
JPH10201771A (en) * 1997-01-20 1998-08-04 Injietsukusu:Kk Crown repair material
JP3867786B2 (en) * 2002-11-05 2007-01-10 相田化学工業株式会社 Method for producing a noble metal shaping clay composition and precious metal sintering products
US20040243133A1 (en) * 2003-03-05 2004-12-02 Therics, Inc. Method and system for manufacturing biomedical articles, such as using biomedically compatible infiltrant metal alloys in porous matrices
NL1027489C2 (en) * 2004-11-11 2006-05-12 Elephant Dental Bv Mixing liquid for dental porcelain.
JP6090664B2 (en) * 2013-03-28 2017-03-08 三菱マテリアル株式会社 Clay-like composition for precious metal sintering body

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2744011A (en) * 1950-04-11 1956-05-01 Diffusion Alloys Ltd Process for the manufacture of sintered articles
US2792302A (en) * 1955-08-29 1957-05-14 Connecticut Metals Inc Process for making porous metallic bodies
US3050386A (en) * 1958-11-22 1962-08-21 Accumulatoren Fabrik Ag Method of producing sinter electrodes
US3052967A (en) * 1959-09-14 1962-09-11 Gen Electric Porous metallic material and method
US3171195A (en) * 1962-06-11 1965-03-02 Johnson Matthey Co Ltd Production of composite metal strip
US3184840A (en) * 1962-08-01 1965-05-25 Texas Instruments Inc Methods of making variegated stock
US3255522A (en) * 1961-10-03 1966-06-14 United States Borax Chem Abrasion resistant material bonding process using boron alloys
US3266893A (en) * 1965-06-17 1966-08-16 Electric Storage Battery Co Method for manufacturing porous sinterable articles
US3287112A (en) * 1963-11-26 1966-11-22 Selas Corp Of America Production of filter membranes
US3350201A (en) * 1964-09-11 1967-10-31 North American Aviation Inc Method of producing sintered alloys of beryllium
US3356537A (en) * 1964-05-25 1967-12-05 Esb Inc Foamed silver electrode and a method for preparing it

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2744011A (en) * 1950-04-11 1956-05-01 Diffusion Alloys Ltd Process for the manufacture of sintered articles
US2792302A (en) * 1955-08-29 1957-05-14 Connecticut Metals Inc Process for making porous metallic bodies
US3050386A (en) * 1958-11-22 1962-08-21 Accumulatoren Fabrik Ag Method of producing sinter electrodes
US3052967A (en) * 1959-09-14 1962-09-11 Gen Electric Porous metallic material and method
US3255522A (en) * 1961-10-03 1966-06-14 United States Borax Chem Abrasion resistant material bonding process using boron alloys
US3171195A (en) * 1962-06-11 1965-03-02 Johnson Matthey Co Ltd Production of composite metal strip
US3184840A (en) * 1962-08-01 1965-05-25 Texas Instruments Inc Methods of making variegated stock
US3287112A (en) * 1963-11-26 1966-11-22 Selas Corp Of America Production of filter membranes
US3356537A (en) * 1964-05-25 1967-12-05 Esb Inc Foamed silver electrode and a method for preparing it
US3350201A (en) * 1964-09-11 1967-10-31 North American Aviation Inc Method of producing sintered alloys of beryllium
US3266893A (en) * 1965-06-17 1966-08-16 Electric Storage Battery Co Method for manufacturing porous sinterable articles

Cited By (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3862840A (en) * 1972-12-20 1975-01-28 Airco Inc Process for manufacture of hard and non-deformable alloys without compacting by sintering in the solid-liquid phase
US4491559A (en) * 1979-12-31 1985-01-01 Kennametal Inc. Flowable composition adapted for sintering and method of making
US4997699A (en) * 1985-04-15 1991-03-05 Itzhak Shoher Material for reinforcing dental structures
US4814008A (en) * 1985-04-15 1989-03-21 Itzhak Shoher Dental material
USRE33371E (en) * 1985-04-15 1990-10-09 Method and material for dental structures
US4742861A (en) * 1985-04-15 1988-05-10 Itzhak Shoher Method and material for dental structures
USRE35367E (en) * 1985-04-15 1996-10-29 Shoher; Itzhak Material for reinforcing dental structures
US4937928A (en) * 1987-10-07 1990-07-03 Elephant Edelmetaal B.V. Method of making a dental crown for a dental preparation by means of a CAD-CAM system
EP0416398A1 (en) * 1989-08-24 1991-03-13 Asahi Kogaku Kogyo Kabushiki Kaisha Paste for bonding granular bone prosthesis and bone prosthesis using same
US5362438A (en) * 1991-02-21 1994-11-08 Elephant Edelmetaal B.V. Powder of dental metal, a process for the preparation thereof, a process for the manufacture of a substructure for a dental restoration and a process for the manufacture of a dental restoration
US5238751A (en) * 1991-02-21 1993-08-24 Elephant Edelmetal B.V. Powder of dental metal, a process for the preparation thereof, a process for the manufacture of a substructure for a dental restoration and a process for the manufacture of a dental restoration
EP0499721A1 (en) * 1991-02-21 1992-08-26 Elephant Edelmetaal B.V. A powder of dental metal, a process for the preparation thereof, a process for the manufacture of a substructure for a dental restoration and a process for the manufacture of a dental restoration
US5336091A (en) * 1991-12-02 1994-08-09 Itzhak Shoher Moldable dental material and method
US5234343A (en) * 1991-12-02 1993-08-10 Itzhak Shoher Moldable dental material and method
US5332622A (en) * 1993-01-19 1994-07-26 Itzhak Shoher Moldable dental material for forming or repairing a dental restoration
US5730600A (en) * 1993-01-19 1998-03-24 Shoher; Itzhak Method for forming a dental restoration
US20120123577A1 (en) * 1995-06-02 2012-05-17 Ormco Corporation Custom orthodontic appliance forming method and apparatus
US9622834B2 (en) * 1995-06-02 2017-04-18 Ormco Corporation Custom orthodontic appliance forming method and apparatus
US6613273B2 (en) 2000-01-10 2003-09-02 Jeneric/Pentron Incorporated Method for the manufacture of dental restorations
US6667112B2 (en) 2000-01-10 2003-12-23 Pentron Laboratory Technologies, Llc Method for the manufacture of dental restorations
US20040109783A1 (en) * 2000-01-10 2004-06-10 Arun Prasad Method for the manufacture of dental restorations
US20070056467A1 (en) * 2000-07-21 2007-03-15 Pentron Ceramics, Inc. Method of making a dental restoration
US6689202B2 (en) 2000-07-21 2004-02-10 Jeneric/Pentron Incorporated Molds for the manufacture of a dental restoration and methods of making dental restorations
US20040245664A1 (en) * 2000-07-21 2004-12-09 Carlino Panzera Method of making a dental restoration
US7943068B2 (en) * 2000-07-21 2011-05-17 Ivoclar Vivadent, Inc. Method of making a dental restoration
WO2002007680A2 (en) 2000-07-21 2002-01-31 Jeneric/Pentron Incorporated Molds for the manufacture of a dental restoration
US6627248B1 (en) 2000-11-10 2003-09-30 Jeneric/Pentron Incorporated Metallization of ceramic restorations
US20030205107A1 (en) * 2000-11-14 2003-11-06 Board Of Trustees Of University Of Illinois Colored metal clay and colored metals
US20050115466A1 (en) * 2001-09-28 2005-06-02 Mitsubishi Materials Corporation Silver powder for silver clay and silver clay comprising the silver powder
US7081149B2 (en) * 2001-09-28 2006-07-25 Mitsubishi Materials Corporation Silver powder for silver clay and silver clay containing this silver powder
US20070113707A1 (en) * 2004-05-14 2007-05-24 Cascone Paul J Dental prosthesis method and alloys
US7892480B2 (en) * 2004-05-14 2011-02-22 The Argen Corporation Dental prosthesis method and alloys

Also Published As

Publication number Publication date Type
FR2036946A1 (en) 1970-12-31 application
DE1915977B2 (en) 1978-08-10 application
GB1271157A (en) 1972-04-19 application
DE1915977A1 (en) 1970-10-08 application
FR2036946B1 (en) 1976-10-01 grant

Similar Documents

Publication Publication Date Title
US6818573B2 (en) Method for molding dental restorations and related apparatus
US2441695A (en) Casting mold
US6354836B1 (en) Methods of producing dental restorations using CAD/CAM and manufactures thereof
US6066274A (en) Method and means for producing a ceramic or metallic product for sintering
US5507981A (en) Method for molding dental restorations
US5250352A (en) Process for the preparation of a dental prosthesis and the prosthesis produced by said process
US4664172A (en) Method for production of investment shell mold for grain-oriented casting of super alloy
US6689202B2 (en) Molds for the manufacture of a dental restoration and methods of making dental restorations
US4179485A (en) Bone prosthesis and method of manufacture thereof
US4917347A (en) Refractory die for making porcelain dental prosthesis and a thermal conducting pin for use therein
US5775912A (en) Method of producing a dental restoration using CAD/CAM
US4742861A (en) Method and material for dental structures
US4767479A (en) Method for bonding ceramic casting cores
US6048205A (en) Biocompatible dental restoration system using layers of high strength ceramic, gold, and porcelain
US2388299A (en) Method of fabricating molds
US4321042A (en) Ceramic dental implant
US4585417A (en) Dental appliance and method of manufacture
EP0817597B1 (en) Process for manufacturing prosthetic dental reconstructions
US6955776B1 (en) Method for making a dental element
US5730600A (en) Method for forming a dental restoration
US3541688A (en) Dental restorations
US4990394A (en) Method and materials for dental structures
US5176747A (en) Dental porcelain for titanium and titanium alloys
US3743003A (en) Making investment shell molds inhibited against reaction with molten reactive and refractory casting metals
US4952530A (en) Dental composite material and process