The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 27, 1999
Filed:
Apr. 14, 1997
Jose Duez, Boulogne sur Mer, FR;
Vincent Bedhome, Desvres, FR;
Debiotech S.A., Lausanne, CH;
Abstract
A buffer reservoir suitable for absorbing surplus ink and a writing instrument including the buffer reservoir are provided. The buffer reservoir includes a mixture of microbeads that are hydrophobic relative to the ink and microbeads that are hydrophilic relative to the ink. The mixture of microbeads may either be uniform throughout the entire volume of the buffer reservoir, or non-uniform throughout the entire volume of the buffer reservoir, with the proportion of hydrophilic microbeads to hydrophobic microbeads being smaller in the zone immediately in contact with the feed tip and larger in the zone farthest away from the feed tip. Preferably, the proportion of hydrophilic microbeads is in the range of about 2% to about 10%, by weight, relative to the total weight of the buffer reservoir. The writing instrument includes a reservoir for liquid ink, a feed tip opening out into the reservoir, and a buffer reservoir.