Infusion bag
US4551336A · kind A · utility
Inventor
Key dates
| Filing date | Dec 22, 1983 |
| Grant date | Nov 5, 1985 |
| Priority date | — |
| Expiry date | Dec 22, 2003 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S493/926
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
An improved infusion bag for preparing an infusion of tea or other infusible substances, comprising a sachet member of liquid-permeable sheet material and a pull string. The pull string is joined at the upper apex of the sachet. At least one ventilative slit is provided below the joint point of the string and the upper apex of the sachet. The sachet can be folded into a generally tetragonal shape. After steeping, and by the action of withdrawing and submerging, the infusible substance swells and sinks to the lower apex of the sachet. The improved infusion bag makes the infusible substance less compacted and overcomes the constraint due to the capillarity of the liquid-permeable sheet material itself and the interface capillarity of the mass of the infusible substance. This gives a higher quantity and higher concentration of infusion liquor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.