Pencil sheath compositions, method for making pencils
US3983195A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 29, 1974 |
| Grant date | Sep 28, 1976 |
| Priority date | — |
| Expiry date | Oct 29, 1994 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S264/14
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Pencils made with a resin-based sheath to replace wood sheaths. A sheath material consisting essentially of a resin binder, a fibrous filler and a metallic soap is extruded around a marking core. The resulting extrudate is immediately chilled after leaving the die, and cut into pencil lengths. The apparatus includes core feeding and transport means, core preheating means and chilling means. The resulting pencils possess the physical qualities associated with wood-sheathed pencils due to the fine, closed cell structure of the sheath material. The surface of the sheath is smooth and may be coated with a pigmented resin or painted.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.