Transfer belt and image formation apparatus

Patent metadata

Field	Value
Publication number	US-9989877-B2
Application number	US-201715712433-A
Country	US
Kind code	B2
Filing date	Sep 22, 2017
Priority date	Oct 4, 2016
Publication date	Jun 5, 2018
Grant date	Jun 5, 2018

Abstract

A transfer belt transfers a toner image carried on a first main surface to a recording medium. When the transfer belt is pressed by using a lower block provided with a hole and an upper block with pressurization force increased at a prescribed rate and thereafter kept constant, E [-] and t0 are curve-fitted to a function E=α×exp(−t0/τ) defined by a time constant τ [s] with respect to an amount of displacement of the transfer belt and a constant α [-], where E [-] is calculated as (a−b)/b, a [μm] represents a maximum value of an amount of displacement of a measurement region, b [μm] represents an amount of displacement of the measurement region after converged, and t0 [s] represents a time period from start of pressurization until the maximum pressurization force, and time constant τ satisfies a condition of 0.015≤τ≤0.1.

First claim

What is claimed is:

1. A transfer belt comprising an elastic layer, the transfer belt serving to transfer a toner image carried on a first main surface which is one of a pair of exposed main surfaces including the first main surface and a second main surface located opposite to each other to a recording medium,
when a pressurized region which is a part of the transfer belt is pressurized with pressurization force reaching 200 [kPa] at a predetermined rate of pressurization [kPa/ms] and thereafter being maintained constant at 200 [kPa] by using a lower block having a projecting curved surface having a width of 20 [mm] and a radius of curvature of 20 [mm] as an upper surface and provided with a hole having a diameter of 1.25 [mm] in a top portion of the projecting curved surface and an upper block having a recessed curved surface having a width of 20 [mm] and a radius of curvature of 20.3 [mm] as a lower surface, placing the transfer belt on the upper surface of the lower block such that the first main surface faces the upper surface of the lower block, and sandwiching the part of the transfer belt between the projecting curved surface and the recessed curved surface by lowering the upper block toward the lower block, the transfer belt satisfying such a condition that E [-] calculated as (a−b)/b and t 0 are curve-fitted to an exponential function expressed as E=α×exp(−t 0 /τ) defined by a time constant τ [s] with respect to an amount of displacement of the transfer belt and a constant a [-], where α [μm] represents a maximum value of an amount of displacement of a measurement region which is a portion in the first main surface corresponding to the hole, b [μm] represents an amount of displacement of the measurement region after convergence of displacement of the measurement region, and t 0 [s] represents a time period from a time point of start of pressurization against the pressurized region until a time point when the pressurization force attains to 200 [kPa], and the time constant τ satisfies a condition of 0.015≤τ0.1.

2. The transfer belt according to claim 1 , the transfer belt further comprising a base layer and a surface layer in addition to the elastic layer, wherein
the elastic layer is provided to cover the base layer and the surface layer is further provided to cover the elastic layer.

3. The transfer belt according to claim 2 , wherein
the base layer is higher in hardness than the elastic layer.

4. An image formation apparatus comprising:
an image carrying portion which carries a toner layer and an intermediate transfer belt;
a primary transfer portion which transfers a toner image carried on the image carrying portion to the intermediate transfer belt; and
a secondary transfer portion which transfers the toner image carried on the intermediate transfer belt to a recording medium,
the secondary transfer portion including
a secondary transfer roller,
an opposed roller opposed to the secondary transfer roller, and
a nip portion formed by the secondary transfer roller and the opposed roller, the intermediate transfer belt being arranged to pass through the nip portion, and the transfer belt according to claim 1 being employed as the intermediate transfer belt.

5. The image formation apparatus according to claim 4 , wherein
a surface of the secondary transfer roller is higher in hardness than a surface of the opposed roller.

Assignees

• Konica Minolta Inc

Inventors

• Tabata Eiji
• Watanabe Makiko
• Mizumoto Nofumi
• Momotani Keiko
• Uetake Shigeo
• Natsuhara Toshiya

Classifications

• G03G2215/2009

  Pressure belt · CPC title

• G03G15/1685

  Structure, details of the transfer member, e.g. chemical composition · CPC title

• G03G15/1675

  with means for controlling the bias applied in the transfer nip · CPC title

• G03G15/5012

  Priority interrupt; Job recovery, e.g. after jamming or malfunction · CPC title

• G03G15/0163 Primary

  primary transfer to the final recording medium · CPC title