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. 31, 2007
Filed:
Jun. 09, 2004
Hachiroh Tosaka, Shizuoka, JP;
Tomiaki Ito, Shizuoka, JP;
Yuji Natori, Shizuoka, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
The toner according to the present invention may be produced from a toner raw composition which comprises a foaming agent, a binder resin and a colorant, wherein the colorant comprises a black metal compound, the foaming agent has a volume-average particle diameter of 2 μm to 50 μm, the toner raw composition turns into a porous mixture while the foaming agent expands at melting and kneading the toner raw composition, and the toner obtained through milling and classifying the porous mixture has a specific density of 1.0 g/cmto 1.3 g/cm, wherein the specific density is determined as follows: 1 gram of toner is pressed at 400 kgf/cmfor five minutes in a discal cavity having a diameter of 20 mm, then the discal toner is removed; the discal toner volume (V) is calculated from the diameter and height, measured at 10 minutes after releasing the pressure on the discal toner, and the discal toner mass (W) is measured; then the specific density is determined from the following formula: Specific Density (ρ)=W/V.