EP-4741938-A1 - IMAGE FORMING METHOD

Abstract

An image forming method for forming a toner image on a continuous medium using a toner. An area ratio of an element derived from an inorganic fine particle to a total area of all elements measured by X-ray photoelectron spectroscopy (ESCA) of the toner image is within a range of 4 to 10%, the toner has a toner base particle, and the toner base particle contains a release agent and an amorphous polyester.

Inventors

• ITO, NATSUKI

Assignees

• Konica Minolta, Inc.

Dates

Publication Date

20260513

Application Date

20251110

Claims (4)

1. An image forming method for forming a toner image on a continuous medium using a toner, wherein an area ratio of an element derived from an inorganic fine particle to a total area of all elements measured by X-ray photoelectron spectroscopy (ESCA) of the toner image is within a range of 4 to 10%, the toner has a toner base particle, and the toner base particle contains a release agent and an amorphous polyester.
2. The image forming method according to claim 1, wherein the element derived from the inorganic fine particle is Si or Ti.
3. The image forming method according to claim 1, wherein the release agent is a hydrocarbon wax.
4. The image forming method according to any one of claims 1 to 3, wherein a content of the amorphous polyester is within a range of 10 to 50% by mass with respect to a content of the toner base particle, the toner image is printed on a white toner image containing a white pigment, and a difference in softening point between the toner and a white toner containing the white pigment is 14°C or less.

Description

BACKGROUND OF THE INVENTION TECHNICAL FIELD The present disclosure relates to an image forming method, and more particularly to an image forming method that ensures separability from the fixing device and excellent post-processing properties without reducing the amount of release agent on the image surface. DESCRIPTION OF RELATED ART In recent years, due to the diversification of printing media and the improvement of the added value of image, electrophotographic printing on printing media other than paper has been required. For example, a continuous medium such as roll sheet or continuous forms is conveyed by a roll-to-roll method, and an image is formed on the conveyed continuous medium by an image forming apparatus. As a toner suitable for continuous media, for example, Japanese Patent Application Laid-Open No. 2016-218448 discloses a toner containing fine particles of polypropylene-based wax. By the way, labels and stickers output by continuous ledger printing machines on continuous ledger media are frequently post-processed by varnishing or laminating. Therefore, the output image produced by a continuous printing machine is required to have improved post-processing properties such as varnish coatability and adhesion compared to the output image produced by a sheet-fed printing machine. However, the printing material used for image formation on continuous media contains a release agent such as wax to ensure separation from the fixing device. Therefore, the release agent repelled varnish and adhesive, resulting in insufficient post-processability. In recent years, high speed and low-temperature fixability have also been required for continuous printing machines, and it has been difficult to achieve both high speed and low-temperature fixability and separation performance in these continuous printing machines. SUMMARY OF THE INVENTION The present disclosure was made in view of the above problems and situations. The problem to be solved by the present disclosure is to provide an image forming method which can ensure separability from the fixing device and excellent post-processing properties, without reducing the amount of release agent on the image surface, even when image formation is performed using a continuous printing machine. Furthermore, the problem to be solved by the present disclosure is to provide an image forming method excellent in high-speed operation and low-temperature fixability in a continuous printing machine. To achieve the object, the present inventors studied the causes of the above problems. The area ratio of elements derived from inorganic fine particles is set within a specific range with respect to the area of all elements measured by X-ray photoelectron spectroscopy (ESCA) of the toner image, and the toner base particle is made to contain a release agent and an amorphous polyester. As a result, it was found that it excels in separability and post-processing properties from the fixing device, and also in the speed-up of the continuous printing machine and low-temperature fixability. To achieve at least one of the abovementioned objects, according to an aspect of the present invention, image forming method reflecting one aspect of the present invention is an image forming method for forming a toner image on a continuous medium using a toner, whereinan area ratio of an element derived from an inorganic fine particle to a total area of all elements measured by X-ray photoelectron spectroscopy (ESCA) of the toner image is within a range of 4 to 10%,the toner has a toner base particle, andthe toner base particle contains a release agent and an amorphous polyester. BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features provided by one or more embodiments of the invention will become more fully understood from the detailed description given hereinbelow and the appended drawings which are given by way of illustration only, and thus are not intended as a definition of the limits of the present invention, wherein: FIG. 1 is a diagram illustrating an overall configuration example of an image forming apparatus according to the present embodiment; andFIG. 2 is a diagram showing main parts of a control system of an image forming apparatus. DETAILED DESCRIPTION Hereinafter, one or more embodiments of the present invention will be described with reference to the drawings. However, the scope of the invention is not limited to the disclosed embodiments. An image forming method according to an aspect of the present disclosure is an image forming method that forms a toner image on a continuous medium using toner. In X-ray photoelectron spectroscopy (ESCA) of the toner image, the area ratio of elements derived from inorganic fine particles to the total area of all elements measured is within the range of 4 to 10%, the toner has a toner base particle, andIt is characterized in that the toner base particle contains a release agent and an amorphous polyester. This feature is a technical feature co