Dental compositions having improved color stability
AssigneeThe Kendall Company
InventorsSamuel C. Temin, Mildred C. Richards
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Abstract
Dental compositions having improved color stability are prepared by employing a redox catalyst system consisting of a hydroperoxide oxidizing agent and a substituted thiourea reducing agent. The composition also comprises a methacrylate monomer, and optionally, a filler and a coupling agent.
Claims16
A polymerizable dental composition having improved color stability consisting essentially of 20-100 parts by weight of at least one methacrylate monomer having 2 to 4 polymerizable double bonds, 0-80 parts by weight of inorganic particulate filler, 0-5.0% by weight based on said methacrylate monomer of silane coupling agent, 0.5-5.0% by weight based on said methacrylate monomer of hydroperoxide oxidizing agent and 0.3-2.0% by weight based on said methacrylate monomer of a substituted thiourea reducing agent having the formula ##EQU1## wherein X is hydrogen or Y and Y is C.sub.1 to C.sub.8 alkyl;
- C.sub.5 or C.sub.6 cycloalkyl;
- -chloro, -hydroxy- or mercapto- substituted C.sub.1 to C.sub.8 allyl;
- C.sub.3 to C.sub.4 alkenyl, C.sub.6 to C.sub.8 aryl;
- chloro-, hydroxy-, methoxy-, or sulfonyl substituted phenyl;
- C.sub.2 to C.sub.8 acyl;
- chloro-, or methoxy- substituted C.sub.2 to C.sub.8 acyl;
- C.sub.7 to C.sub.8 aralkyl;
- or chloro- or methoxy- substituted C.sub.7 to C.sub.8 aralkyl.
Dependencies are inferred from the claim text.