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Title: Impression materials for dentistry



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Claims: What is claimed is:

1. 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.

2. A material according to claim 1 wherein the isocyanate (a) is a diisocyanate.

3. A material according to claim 2 wherein the diisocyanate (a) is hexamethylene-diisocyanate, toluylene-diisocyanate, isophorone-diisocyanate or diphenylmethane-4,4'-diisocyanate.

4. A material according to claim 2 wherein the dihydroxy compound (b) has a molecular weight of from 1,000 to 8,000.

5. 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).

6. 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).

7. A process according to claim 5 wherein a polymerization inhibitor is present to prevent premature gelling.

8. A process according to claim 6 wherein a polymerization inhibitor is present to prevent premature gelling.

9. An impression material according to claim 1 additionally containing a hardening catalyst.

10. A material according to claim 1 wherein the dihydroxy compound (b) has a molecular weight of from 2,000 to 4,000.

11. A material according to claim 2 wherein the dihydroxy compound (b) has a molecular weight of from 2,000 to 4,000.

Other info:


Inventors: Walkowiak, Michael (Cologne, DE, US)
Schulz, Hans-Hermann (Leichlingen, DE, US)
Rosenkranz, Hans J. (Krefeld, DE, US)

Application Number: 904071
Filing Date: 1978-05-08
Publication_date: 1980-01-08
Assignee: Bayer Aktiengesellschaft (Leverkusen, DE)
Primary Class(es): 528/75 523/109, 524/590, 525/123, 528/50, 528/52, 528/58
Other Classes:
US Patent Ref:
3297745Jan, 1967Fekete et al.260/471.
3509234Apr, 1970Burlant et al.260/859.
3553174Jan, 1971Hausslein et al.260/77.
3641199Feb, 1972Niederhauser et al.260/859.
3644569Feb, 1972Pietsch et al.260/835.
3709866Jan, 1973Waller260/27.
3825518Jul, 1974Foster et al.260/DIG.
3862920Jan, 1975Foster et al.260/DIG.
3878036Apr, 1975Chang428/424.
3907751Sep, 1975Knight et al.528/75.

Other Refs:
Primary Examiner: Cockeram, H. S.
Assistant Examiner:
Attorney: Sprung, Felfe, Horn, Lynch & Kramer