| 摘要 |
Gas-free paste or gel dentifrices are made by a process which includes producing a degassed gel of a gelling agent in a polyhydric alcohol, and admixing it with other dentifrice constituents, including powdered light weight polishing agent, under vacuum. Preferably, the powdered polishing agent is degassed in a vacuum hopper, before addition to the gel base in a mixer. Where no vacuum hopper or similar facilities are available, however, powdered polishing agent may be added to the gel in a suitable mixer with adequate head space and any gas present is removed from it by vacuum while it is resting on the surface of the gel, after which the polishing agent is mixed in with the gel.
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