| 摘要 |
<p>In order to make it possible to regulate at will the mixing time and working time of materials for taking impressions, for example dental impressions, or to neutralise the accelerating effect on the mixing and working time of impression materials due to increases in the temperature of the working environment and/or increase in the hardness of the water used for mixing, a suitable regulator is added in a selected quantity at the time of preparation of the mixture. The mixture already comprises a retarder of predetermined quantity. Where a tribasic alkaline orthophosphate or equivalent retarder is present, a regulator is added consisting of a lithium salt, such as chloride, nitrate, perchlorate, sulphate or carbonate.</p> |
