US 11,036,161 B2 · Developer bearing member, developing apparatus, process cartridge, and image forming apparatus

Abstract

A developer bearing member including: a rotational shaft; and an elastic layer on an outer circumference surface of the rotational shaft, developer being borne on a surface of the elastic layer, wherein the elastic layer is configured such that a load per unit area of a contact portion between one surface of a flat glass plate and the surface of the elastic layer is to be 5.8 N/mm2 or more, in a state that the one surface of the flat glass plate being parallel with an axis direction of the rotational shaft and the one surface of the flat glass plate coming into contact with the surface of the elastic layer with a predetermined penetration level, and wherein a ten-point average roughness Rzjis on the surface of the elastic layer is greater than a volume-average particle diameter of a particle of the developer.

Claims29

Dependent claims

A developer bearing member including:

a rotational shaft;
and
an elastic layer formed on an outer circumference surface of the rotational shaft, developer being borne on a surface of the elastic layer,
wherein the elastic layer is configured such that, a load per unit area of a contact portion between one surface of a flat glass plate and the surface of the elastic layer is to be 5.8 N/mm2 or more, in a state that the one surface of the flat glass plate being parallel with an axis direction of the rotational shaft and the one surface of the flat glass plate coming into contact with the surface of the elastic layer with a predetermined penetration level, and
wherein a ten-point average roughness Rzjis on the surface of the elastic layer is greater than a volume-average particle diameter of a particle of the developer.

2 more elements

A developing apparatus comprising:

a developer bearing member for supplying developer to an image bearing member for bearing an image;
and
a regulating member for regulating a thickness of the developer borne by the developer bearing member,
the developer bearing member including:
a rotational shaft;
and
an elastic layer formed on an outer circumference surface of the rotational shaft, developer being borne on a surface of the elastic layer,
wherein the elastic layer is configured such that, a load per unit area of a contact portion between one surface of a flat glass plate and the surface of the elastic layer is to be 5.8 N/mm2 or more, in a state that the one surface of the flat glass plate being parallel with an axis direction of the rotational shaft and the one surface of the flat glass plate coming into contact with the surface of the elastic layer with a predetermined penetration level, and
wherein a ten-point average roughness Rzjis on the surface of the elastic layer is greater than a volume-average particle diameter of a particle of the developer.

6 more elements

Dependencies are inferred from the claim text.

Facts

Application

16/849,277Filed 15 Apr 2020

Priority

JP JP2019-07933818 Apr 2019

Published

US 2020/0333726 A122 Oct 2020

Granted

15 Jun 2021

Term ends

Not estimatedThe source records don’t support an estimate.

Classification7 codes

G03G 15/0808
On a donor element, e.g. belt, roller: characterised by the developer supplying means, e.g. structure of developer supply roller
G03G 15/0818
On a donor element, e.g. belt, roller: characterised by the structure of the donor member, e.g. surface properties
G03G 15/0812
On a donor element, e.g. belt, roller: characterised by the developer regulating means, e.g. structure of doctor blade
G03G 21/1814
Arrangements or disposition of the complete process cartridge or parts thereof: details of parts of process cartridge, e.g. for charging,…

Developer bearing member, developing apparatus, process cartridge, and image forming apparatus

Life of this patent

Developer bearing member, developing apparatus, process cartridge, and image forming apparatus

Life of this patent

Abstract

Claims29