Very high viscosity polyvinylsiloxane impression material
US5955513A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 1, 1998 |
| Grant date | Sep 21, 1999 |
| Priority date | — |
| Expiry date | Jun 1, 2018 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K6/90
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
Improved very high viscosity (putty) two component polymerizable polyorganosiloxane composition for use in making dental impressions, having improved tear strength, handling and wettability. Improved tear strength results from inclusion of a quadri-functional polysiloxane having a vinyl content of 0.16 to 0.24 m-mole/g. Working time is maintained by including sufficient amounts of a retarder composition that delays onset of the vinyl polymerization. Handling is improved by the addition of a very high viscosity linear vinyl terminated polydimethylsiloxane which reduces tackiness and improves the shelf stability. Wettability is improved by including a surfactant resulting in a surface contact angle with water at three minutes of less than 50.degree.. The surfactant chosen has an HLB of 8-11, such that the wetting contact angle is achieved within less than two minutes and remains wetting throughout the working time of the impression taking, substantially improving the impression making process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.