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Homogenous bonding of dispersed phase alloy

Assignee: Manufacturers Hanover Trust Co
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Filing: 1979-12-17
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Granted: 1981-03-10
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Expires: 1999-12-17
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Abstract

Abstract Dispersed phase dental alloy made by mechanically blending mixtures of lathe cut dental amalgam alloy particles and spheroidal silver-copper alloy particles has superior properties as an amalgam when a mechanical blend of the mixture of alloy particles is treated prior to amalgamation with dilute aqueous mineral acid solutions or with methyl alcohol.

Inventors

  • 👤 Charles F. Burns

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 09:23
CPC Classifications
A; A61; A61K; A61K6/00; A61K6/80; A61K6/84; A61K6/847; Y; Y10; Y10S; Y10S75/00; Y10S75/955

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 239 words
In a process for making a dental alloy mixture which will amalgamate to form a restoration with superior compressive strength and low creep properties by mechanically mixing lathe cut dental amalgam alloy particles and silver-copper alloy spheres, the improvement comprising treating a mechanical mixture of lathe cut dental amalgam alloy particles of minus 200 mesh, having the composition: silver 40--75%, tin 20--30%; copper 2--30%, and from 0 to 30% of one or more metals selected from the group consisting of indium, zinc, gold, mercury, manganese, cadmium and aluminum, and spheroidal silver-copper alloy of minus 325 mesh, having the composition: silver 54--72%; copper 24--40%, and varying amounts of one or more metals selected from the group consisting of nickel, zinc, tin or indium, the said mixture of alloys containing from about 20 to 50% by weight of the silver-copper alloy, with an effective amount of a treating solution selected from the group consisting of 5 volume % to 100 volume % hydrochloric acid, 5 volume % to 50 volume % sulfuric acid, 5 volume % to 20 volume % nitric acid and 5 volume % to 100 volume % methyl alcohol to aglommerate the mixture of alloy particles, separating the aglommerated mixture of alloy particles from the treating solution, washing the agglommerated alloy particles with water to remove the treating solution when the treating solution is one of the mineral acids, and finally drying the aglommerated mixture of alloy particles.
Claim 2
Dependent Claim 239 words
In a process for making a dental alloy mixture which will amalgamate to form a restoration with superior compressive strength and low creep properties by mechanically mixing lathe cut dental amalgam alloy particles and silver-copper alloy spheres, the improvement comprising treating a mechanical mixture of lathe cut dental amalgam alloy particles of minus 200 mesh, having the composition: silver 40--75%, tin 20--30%; copper 2--30%, and from 0 to 30% of one or more metals selected from the group consisting of indium, zinc, gold, mercury, manganese, cadmium and aluminum, and spheroidal silver-copper alloy of minus 325 mesh, having the composition: silver 54--72%; copper 24--40%, and varying amounts of one or more metals selected from the group consisting of nickel, zinc, tin or indium, the said mixture of alloys containing from about 20 to 50% by weight of the silver-copper alloy, with an effective amount of a treating solution selected from the group consisting of 5 volume % to 100 volume % hydrochloric acid, 5 volume % to 50 volume % sulfuric acid, 5 volume % to 20 volume % nitric acid and 5 volume % to 100 volume % methyl alcohol to aglommerate the mixture of alloy particles, separating the aglommerated mixture of alloy particles from the treating solution, washing the agglommerated alloy particles with water to remove the treating solution when the treating solution is one of the mineral acids, and finally drying the aglommerated mixture of alloy particles.
Claim 3
Dependent Claim 16 words
The process of claim 1 in which the treating solution is 10 volume % hydrochloric acid.
Claim 4
Dependent Claim 30 words
The process of claim 1 in which the effective amount of treating solution is within the range of 1 to 5 cc. of treating solution per gram of alloy mixture.
Claim 5
Dependent Claim 40 words
The process of claim 1 in which the concentration of the spheroidal silver-copper alloy in the mechanical mixture of alloys is one-third part by weight and the concentration of the lathe cut dental amalgam alloy is two-thirds parts be weight.
Claim 6
Dependent Claim 21 words
The process of claim 1 in which the spheroidal silver-copper alloy has the composition 72% weight silver and 28% weight copper.
Claim 7
Dependent Claim 21 words
The process of claim 1 in which the particle size of the lathe cut dental amalgam alloy is minus 400 mesh.
Claim 8
Dependent Claim 26 words
The process of claim 1 in which the composition of the lathe cut dental amalgam alloy is silver--70%, tin--25%, copper--3.5% and zinc--1.5%, all percentages by weight.
Claim 9
Dependent Claim 16 words
The process of claim 1 in which the spheroidal silver-copper alloy is minus 400 mesh size.
Claim 10
Dependent Claim 37 words
The dental amalgam prepared by triturating the dental alloy mixture of claim 1, which, after amalgamation, has a one-hour compressive strength of about 31,500 to 34,500 pounds per square inch, and a static creep of about 0.15%.

References Cited (Backward Citations)

US1278744A Cited
US3305356A Cited
US4039329A Cited
US3980472A Cited
US4080199A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-03-09 1984-09-08 1985-03-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-03-09 1988-09-08 1989-03-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-03-09 1992-09-08 1993-03-10 $7700.00 Window Closed / Lapsed

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