Colour pencil lead
US9988546B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 14, 2015 |
| Grant date | Jun 5, 2018 |
| Priority date | — |
| Expiry date | Dec 14, 2035 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB43K19/18
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
The present invention concerns an extrudable, unexpanded color pencil lead, comprising, by weight relative to the total weight of the lead: between 25 and 45%, and advantageously between 30 and 40%, of a polyolefin; between 25 and 50%, and advantageously between 30 and 40%, of a colorless mineral filler; between 4 and 20%, and advantageously between 5 and 15%, of a pigment coated with or mixed with a polyolefin wax; between 0 and 10%, and advantageously between 2 and 10%, of an additive, and between 10 and 30%, and advantageously between 15 and 25%, of stearate chosen from magnesium stearate, calcium stearate and the mixture of same. It further concerns the color pencil comprising a lead according to the invention.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.