Patent US4182829A successfully refreshed from Google Patents.
US4182829A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Impression materials for dentistry
Assignee: Bayer AG
•
Filing: 1978-05-08
•
Granted: 1980-01-08
•
Expires: 1998-05-08
Abstract
Abstract The invention provides impression materials for use in dentistry comprising the reaction product of (a) a diisocyanate or triisocyanate, (b) a dihydroxy compound having a molecular weight of from 300 to 10,000 and (c) an unsaturated monohydroxy compound. The invention also includes processes for preparing said impression materials.
Inventors
- 👤 Michael Walkowiak
- 👤 Hans-Hermann Schulz
- 👤 Hans J. Rosenkranz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:55
CPC Classifications
C; C08; C08F; C08F299/00; C08F299/02; C08F299/06; A; A61; A61K; A61K6/00; A61K6/90; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/67; C08G18/671; C08G18/672
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
86 words
An impression material for use in dentistry comprising (I) the reaction product of (a) a diisocyanate or triisocyanate, (b) a dihydroxy compound selected from the group consisting of polyesters, polyethers, polythioethers, polyacetals, polycarbonates and polyester-amides having a molecular weight of from 300 to 10,000 and (c) a derivative of acrylic and/or methacrylic acid having a hydroxyl group wherein the molar ratio of compounds (a), (b) and (c) is 2:1:2, and (II) an inert dental carrier, said impression material having a hardening time of about 4-5 minutes.
Claim 2
Dependent Claim
86 words
An impression material for use in dentistry comprising (I) the reaction product of (a) a diisocyanate or triisocyanate, (b) a dihydroxy compound selected from the group consisting of polyesters, polyethers, polythioethers, polyacetals, polycarbonates and polyester-amides having a molecular weight of from 300 to 10,000 and (c) a derivative of acrylic and/or methacrylic acid having a hydroxyl group wherein the molar ratio of compounds (a), (b) and (c) is 2:1:2, and (II) an inert dental carrier, said impression material having a hardening time of about 4-5 minutes.
Claim 3
Dependent Claim
13 words
A material according to claim 1 wherein the isocyanate (a) is a diisocyanate.
Claim 4
Dependent Claim
16 words
A material according to claim 2 wherein the diisocyanate (a) is hexamethylene-diisocyanate, toluylene-diisocyanate, isophorone-diisocyanate or diphenylmethane-4,4'-diisocyanate.
Claim 5
Dependent Claim
20 words
A material according to claim 2 wherein the dihydroxy compound (b) has a molecular weight of from 1,000 to 8,000.
Claim 6
Dependent Claim
31 words
A process for preparing an impression material according to claim 1 which comprises mixing the dihydroxy compound (b) with the monohydroxy compound (c), then reacting the mixture with the diisocyanate (a).
Claim 7
Dependent Claim
29 words
A process for preparing an impression material according to claim 1 which comprises reacting equimolar amounts of compounds (a) and (c), then reacting the reaction product with compound (b).
Claim 8
Dependent Claim
16 words
A process according to claim 5 wherein a polymerization inhibitor is present to prevent premature gelling.
Claim 9
Dependent Claim
16 words
A process according to claim 6 wherein a polymerization inhibitor is present to prevent premature gelling.
Claim 10
Dependent Claim
12 words
An impression material according to claim 1 additionally containing a hardening catalyst.
Claim 11
Dependent Claim
20 words
A material according to claim 1 wherein the dihydroxy compound (b) has a molecular weight of from 2,000 to 4,000.
Claim 12
Dependent Claim
20 words
A material according to claim 2 wherein the dihydroxy compound (b) has a molecular weight of from 2,000 to 4,000.
References Cited (Backward Citations)
US3297745A
Cited
US3509234A
Cited
US3553174A
Cited
US3644569A
Cited
US3641199A
Cited
US3878036A
Cited
US3709866A
Cited
US3907751A
Cited
US3825518A
Cited
US3862920A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-01-07 | 1983-07-09 | 1984-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-01-07 | 1987-07-09 | 1988-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-01-07 | 1991-07-09 | 1992-01-08 | $7700.00 | Window Closed / Lapsed |