Patent US4721735A successfully refreshed from Google Patents.
US4721735A
Expired / Lapsed
US
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Frangible light cured compositions
Assignee: Dentsply Research and Development Corp
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Filing: 1986-01-23
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Granted: 1988-01-26
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Expires: 2006-01-23
Abstract
Abstract Novel compositions, especially light curable compositions, are provided which are coherent, but frangible when cured. Preferred compositions comprising a major proportion of inert, preferably inorganic filler material, polymerizable resin and frangibility enhancing material are provided which are light curable. The materials are particularly useful for "temporary" dental fillings and removable endodontic fillings. The cured materials are easily dissected, comminuted and removed as desired after curing without trauma to the filled teeth.
Inventors
- 👤 Richard J. Bennett
- 👤 Robert V. Hare
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 20:06
CPC Classifications
A; A61; A61K; A61K6/00; A61K6/50; A61K6/54; A61K6/80; A61K6/884; A61K6/891; A61K6/893
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
85 words
An actinic light curable composition, frangible when cured, comprising: a major proportion of inert filler, and polymerizable resin blend comprising: from about 15% to about 85% by weight of the blend of urethane acrylic resin; from about 15% to about 85% by weight of the blend of urethane polyether resin; and a photosensitizing system capable of curing the composition upon irradiation with actinic light; and from about 5% to about 15% by weight of the composition of a frangibility enhancing material comprising particulate organic polymer.
Claim 2
Dependent Claim
85 words
An actinic light curable composition, frangible when cured, comprising: a major proportion of inert filler, and polymerizable resin blend comprising: from about 15% to about 85% by weight of the blend of urethane acrylic resin; from about 15% to about 85% by weight of the blend of urethane polyether resin; and a photosensitizing system capable of curing the composition upon irradiation with actinic light; and from about 5% to about 15% by weight of the composition of a frangibility enhancing material comprising particulate organic polymer.
Claim 3
Dependent Claim
20 words
The composition of claim 1 curable to a coherent mass having a diametral tensile strength less than about 2,500 psi.
Claim 4
Dependent Claim
23 words
The composition of claim 1 wherein the urethane acrylic resin comprises the reaction product of a hydroxyalkyl acrylate or methacrylate with alkyl diisocyanate.
Claim 5
Dependent Claim
26 words
The composition of claim 1 where in the urethane polyether resin comprises the reaction product of polyether polyol and isocyanatoalkyl ester of alpha-beta unsaturated carboxylic acid.
Claim 6
Dependent Claim
25 words
The composition of claim 3 wherein the urethane polyether resin comprises the reaction product of polyether polyol and isocyanatoalkyl ester of alpha-beta unsaturated carboxylic acid.
Claim 7
Dependent Claim
13 words
The composition of claim 1 wherein the frangibility enhancing organic polymer comprises polyalkylene.
Claim 8
Dependent Claim
13 words
The composition of claim 5 wherein the frangibility enhancing material comprises particulate polyalkylene.
Claim 9
Dependent Claim
25 words
The composition of claim 1 wherein the photosensitizing system comprises an alpha diketone and an amine reducing agent and the actinic light is visible light.
Claim 10
Dependent Claim
26 words
The composition of claim 5 wherein the photosensitizing system comprises an a alpha diketone and an amine reducing agent and the actinic light is visible light.
Claim 11
Dependent Claim
25 words
The composition of claim 7 wherein the photosensitizing system comprises an alpha diketone and an amine reducing agent and the actinic light is visible light.
Claim 12
Dependent Claim
50 words
An actinic light curable composition, frangible when cured, comprising: actinic light polymerizable acrylic oligomer or oligomer blend; a major proportion of inert filler; a photosensitizing system capable of curing the composition upon irradiation with actinic light; and organic particulate polymer in an amount sufficient to render the cured composition frangible.
Claim 13
Dependent Claim
50 words
An actinic light curable composition, frangible when cured, comprising: actinic light polymerizable acrylic oligomer or oligomer blend; a major proportion of inert filler; a photosensitizing system capable of curing the composition upon irradiation with actinic light; and organic particulate polymer in an amount sufficient to render the cured composition frangible.
Claim 14
Dependent Claim
27 words
The composition of claim 11 wherein the cured composition has a tensile strength less than about 2500 psi and a compressive modulus greater than about 10,000 psi.
Claim 15
Dependent Claim
27 words
The composition of claim 11 wherein the particulate organic polymer is present in an amount of from about 5% to about 15% by weight of the composition.
Claim 16
Dependent Claim
14 words
The composition of claim 11 wherein the oligomer or oligomer blend comprises urethane oligomer.
Claim 17
Dependent Claim
11 words
The composition of claim 11 wherein the inert filler is inorganic.
Claim 18
Dependent Claim
12 words
The composition of claim 11 wherein the particulate organic polymer is polyalkylene.
Claim 19
Independent Claim
120 words
A method of forming a coherent, but frangible, shaped body comprising: providing an actinic light curable composition comprising: a major proportion of inert filler; polymerizable resin blend comprising: from about 15% to about 85% by weight of the blend of urethane acrylic resin; from about 15% to about 85% by weight of the blend of urethane polyether resin; and a photosensitizing system capable of curing the composition upon irradiation with actinic light; and from about 5% to about 15% by weight of the composition of a frangibility enhancing material comprising particulate organic polymer: forming said composition into a shape; and irradiating the shaped composition with actinic light for a time sufficient to cure the composition to provide the shaped body.
Claim 20
Independent Claim
120 words
A method of forming a coherent, but frangible, shaped body comprising: providing an actinic light curable composition comprising: a major proportion of inert filler; polymerizable resin blend comprising: from about 15% to about 85% by weight of the blend of urethane acrylic resin; from about 15% to about 85% by weight of the blend of urethane polyether resin; and a photosensitizing system capable of curing the composition upon irradiation with actinic light; and from about 5% to about 15% by weight of the composition of a frangibility enhancing material comprising particulate organic polymer: forming said composition into a shape; and irradiating the shaped composition with actinic light for a time sufficient to cure the composition to provide the shaped body.
Claim 21
Dependent Claim
19 words
The method of claim 17 wherein the shaped body has a diametral tensile strength less than about 2,500 psi.
Claim 22
Dependent Claim
23 words
The method of claim 17 wherein the urethane acrylic resin comprises the reaction product of a hydroxyalkyl acrylate or methacrylate with alkyl diisocyanate.
Claim 23
Dependent Claim
25 words
The method of claim 17 wherein the urethane polyether resin comprises the reaction product of polyether polyol and isocyanatoalkyl ester of alpha-beta unsaturated carboxylic acid.
Claim 24
Dependent Claim
25 words
The method of claim 19 wherein the urethane polyether resin comprises the reaction product of polyether polyol and isocyanatoalkyl ester of alpha-beta unsaturated carboxylic acid.
Claim 25
Dependent Claim
13 words
The method of claim 17 wherein the frangibility enhancing organic polymer comprises polyalkylene.
Claim 26
Dependent Claim
13 words
The method of claim 21 wherein the particulate organic polymer comprises particulate polyalkylene.
Claim 27
Dependent Claim
25 words
The method of claim 17 wherein the photosensitizing system comprises an alpha diketone and an amine reducing agent and the actinic light is visible light.
Claim 28
Dependent Claim
25 words
The method of claim 23 wherein the photosensitizing system comprises an alpha diketone and an amine reducing agent and the actinic light is visible light.
Claim 29
Dependent Claim
40 words
In an actinic light curable composition comprising ethylenically unsaturated, polymerizable resin or resin blend, inert filler and a photosensitizing system, the improvement comprising including in the composition particulate organic polymer in an amount sufficient to render the cured composition frangible.
Claim 30
Dependent Claim
40 words
In an actinic light curable composition comprising ethylenically unsaturated, polymerizable resin or resin blend, inert filler and a photosensitizing system, the improvement comprising including in the composition particulate organic polymer in an amount sufficient to render the cured composition frangible.
Claim 31
Dependent Claim
12 words
The composition of claim 26 wherein the particulate organic polymer comprises polyalkylene.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-01-25 | 1991-07-27 | 1992-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-01-25 | 1995-07-27 | 1996-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-01-25 | 1999-07-27 | 2000-01-26 | $7700.00 | Window Closed / Lapsed |