Ricoh Company, Ltd.

Shoki Matsuda

Keisuke Tada

Fumihiko Chimoto

Hiyori Fujino

Ayumi Satoh

Daisuke Misawa

Yasuyuki Sanui

Takashi Okano

Yellow toner with excellent cleanability, transferability and device contamination resistance is provided. When intensity of spectrum at wavenumber λ, at which total intensity of Raman spectrums of toner particles from 950 cmthrough 3,250 cmin Raman spectroscopy of toner is maximum, is normalized to 1, and distribution is generated for ≥300 particles regarding LC calculated by [LC (%)=CHrate (%)−CHrate (%)] based on CHrate (%) defined as [(I−I)/I]×100 and CHrate (%) defined as [(I−I)/I]×100 where Iand Irepresent integrated intensities of spectrums of center and surface portions of each particle from 2,750 cmthrough 3,250 cm, and Irepresents average of Iand Iof all particles, percentage by number of particles having LC deviating from LC distribution median by absolute value of ≥25.0; is ≥1.0% by number and ≤25.0% by number.

Toner, developer, process cartridge, image forming apparatus, and image forming method

A magenta toner is provided. The magenta toner comprises toner particles each comprising a binder resin and a colorant. From 1.0% to 25.0% by number of the toner particles have a CH rate of 25.0% or more in absolute value. The CH rate is calculated from the following formula (1):rate(%)=[()/]×100  Formula (1)where, in a Raman spectrum of each toner particle, Irepresents an integrated intensity within a wavenumber region of from 2,750 to 3,250 cmwhen an intensity at a wavenumber λ within a wavenumber region of from 1,200 to 3,250 cmis s normalized to 1, where a total intensity of all the toner particles is maximum at the wavenumber λ; and Irepresents an average of the I.

Magenta toner, developer, toner accommodating unit, image forming apparatus, and image forming method

A cyan toner is provided. The cyan toner comprises toner particles each comprising a binder resin and a colorant. From 1.0% to 20.0% by number of the toner particles have a CH rate of 7.0% or more in absolute value. The CH rate is calculated from the following formula (1):CH rate (%)=[()/]&#xd7;100&#x2003;&#x2003;Formula (1)where, in a Raman spectrum of each toner particle, Irepresents an integrated intensity within a wavenumber region of from 2,600 to 3,180 cmwhen an intensity at a wavenumber &#x3bb; within a wavenumber region of from 2,600 to 2,800 cmis s normalized to 1, where a total intensity of all the toner particles is maximum at the wavenumber &#x3bb;; and Irepresents an average of the I.

Cyan toner, developer, toner accommodating unit, image forming apparatus, and image forming method

A yellow toner is provided. The yellow toner comprises toner particles each comprising a binder resin and a colorant, and 1.0% to 15.0% by number of the toner particles have a CH rate of 25.0% or more in absolute value. Here, the CH rate is calculated from the following formula (1):rate (%)=[()/]&#xd7;100&#x2003;&#x2003;Formula (1)where Irepresents an integrated intensity within a wavenumber region of from 2,750 to 3,250 cmwhen an intensity at a wavenumber &#x3bb; within a wavenumber region of from 950 to 3,250 cmis normalized to 1 in a Raman spectrum of each toner particle; and Irepresents an average of the I.

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Shizuoka, Japan

Shoki Matsuda