Ink follower for water-base ballpoint pens and method of manufacturing the same
US6376560B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 7, 2000 |
| Grant date | Apr 23, 2002 |
| Priority date | — |
| Expiry date | Apr 7, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/3109
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
This invention relates to ink follower for a water-base ballpoint pen with its bubbles removed, time-dependent stability, less oil separation, and greatly reduced lot-to-lot viscosity difference and associated performance difference, and a method for manufacturing the same. After addition of thickener, the follower is made depressurized preferably at 0.2 atm or lower. Simultaneous heating and stirring are preferable. When the ink follower is solely debubbled in advance, fine bubbles contained in particulate silica, clay thickener, etc. can be very highly removed even if the centrifugal debubbling is not so strong and there is no bad affection to the writing property of the pen. It is also possible that, after adding the thickener, a centrifugal force greater than or equal to 200-fold of the gravitational acceleration is applied to debubble.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.