Liquid discharge system, image forming apparatus, and liquid discharge method

Patent metadata

Field	Value
Publication number	US-10744795-B2
Application number	US-201816162311-A
Country	US
Kind code	B2
Filing date	Oct 16, 2018
Priority date	Oct 24, 2017
Publication date	Aug 18, 2020
Grant date	Aug 18, 2020

Abstract

A liquid discharge system includes a pretreatment execution device to perform pretreatment on a medium and a liquid discharge head to discharge liquid onto the medium based on image information on an image to be output. The liquid discharge system further includes circuitry configured to control a manner of the pretreatment based on the image information.

First claim

What is claimed is:

1. A liquid discharge system comprising:
a pretreatment execution device configured to apply one of multiple types of pretreatment agents having different levels of aggregating agent concentration on a medium;
a liquid discharge head configured to discharge liquid onto the medium based on image information on an image to be output; and
circuitry configured to analyze the image information to determine whether an area of printing on the medium includes a photograph printing area or a line printing area, and to determine whether a dot to be applied to a dot location on the medium by the liquid discharge head belongs to the photograph printing area or the line printing area,
the circuitry configured, in response to determining the dot belongs to the photographic printing area, to direct the pretreatment execution device to apply, at the dot location, pretreatment agent having a first aggregating agent concentration that causes a diameter of the dot to increase and a color density of the dot to be thicker toward a center of the dot, and
the circuitry configured, in response to determining the dot belongs to the line printing area, to direct the pretreatment execution device to apply, at the dot location, pretreatment agent having a second aggregating agent concentration that causes a diameter of the dot to decrease and the color density of the dot to be uniform.

2. The liquid discharge system according to claim 1 ,
wherein the circuitry is configured to control a concentration of a reactant in the pretreatment agent applied to the medium.

3. The liquid discharge system according to claim 1 ,
wherein the circuitry is configured to control the pretreatment execution device to increase a speed of spreading of wetting of the liquid applied onto the medium, based on the image information.

4. The liquid discharge system according to claim 1 ,
wherein the circuitry is configured to control the pretreatment execution device to reduce a speed of spreading of wetting of the liquid applied onto the medium, based on the image information.

5. The liquid discharge system according to claim 1 ,
wherein the circuitry is configured to control an ink dot profile, including a size and color density, with a concentration of a reactant in the pretreatment agent.

6. The liquid discharge system according to claim 1 ,
wherein the image information includes image type information indicating an image type of the image to be output, the image type being one of letter, photograph, and table, and
wherein the circuitry is configured to control the manner of the pretreatment based on the image type information.

7. The liquid discharge system according to claim 1 ,
wherein the liquid discharged by the liquid discharge head contains a colorant, and
wherein, as the pretreatment, the pretreatment execution device is configured to perform a process to change a dispersion state of the colorant contained in the liquid applied onto the medium for controlling a behavior of the liquid.

8. The liquid discharge system according to claim 1 , further comprising an image type determiner configured to determine an image type of the image to be output, the image type being one of letter, photograph, and table,
wherein the circuitry is configured to control the manner of the pretreatment in accordance with the image type determined by the image type determiner.

9. The liquid discharge system according to claim 1 ,
wherein the pretreatment agent has a 15 ms dynamic surface tension of from 35 to 65 mN/m.

10. The liquid discharge system according to claim 1 ,
wherein the pretreatment agent has a static surface tension of from 20 to 35 mN/m.

11. The liquid discharge system according to claim 1 ,
wherein the pretreatment agent contains a multivalent metal salt, glycerin, and a betaine compound having a molecular weight of from 100 to 200, and
wherein a mass ratio of a total amount of the glycerin and the betaine compound to an amount of the multivalent metal salt is from 1.05 to 2.50.

12. The liquid discharge system according to claim 11 , wherein the mass ratio is from 1.05 to 1.40.

13. The liquid discharge system according to claim 11 ,
wherein a mass ratio of an amount of the betaine compound to the total amount of the glycerin and the betaine compound is from 0.1 to 0.5.

14. An image forming apparatus comprising:
a pretreatment execution device to apply one of multiple types of pretreatment agents having different levels of aggregating agent concentration on a medium;
a liquid discharge head to discharge liquid onto the medium based on image information on an image to be output; and
circuitry configured to analyze the image information to determine whether an area of printing on the medium includes a photograph printing area or a line printing area, and to determine whether a dot to be applied to a dot location on the medium by the liquid discharge head belongs to the photograph printing area or the line printing area,
the circuitry configured, in response to determining the dot belongs to the photographic printing area, to direct the pretreatment execution device to apply, at the dot location, pretreatment agent having a first aggregating agent concentration that causes a diameter of the dot to increase and a color density of the dot to be thicker toward a center of the dot; and
the circuitry configured, in response to determining the dot belongs to the line printing area, to direct the pretreatment execution device to apply, at the dot location, pretreatment agent having a second aggregating agent concentration that causes a diameter of the dot to decrease and the color density of the dot to be uniform.

15. A liquid discharge method comprising:
applying one of multiple types of pretreatment agents having different levels of aggregating agent concentration on a medium;
discharging liquid onto the medium based on the image information;
analyzing the image information to determine whether an area of printing on the medium includes a photograph printing area or a line printing area;
determining whether a dot to be applied to a dot location on the medium by the liquid discharge head belongs to the photograph printing area or the line printing area;
in response to determining the dot belongs to the photographic printing area, applying at the dot location pretreatment agent having a first aggregating agent concentration that causes a diameter of the dot to increase and a color density of the dot to be thicker toward a center of the dot; and
in response to determining the dot belongs to the line printing area, applying at the dot location pretreatment agent having a second aggregating agent concentration that causes a diameter of the dot to decrease and the color density of the dot to be uniform.

Assignees

• Harada Yoshihiro
• Tamai Takashi
• Hanazawa Atsufumi
• Kojima Sayuri
• Ricoh Co Ltd

Inventors

• Harada Yoshihiro
• Tamai Takashi
• Hanazawa Atsufumi
• Kojima Sayuri

Classifications

• D06P5/002

  Locally enhancing dye affinity of a textile material by chemical means · CPC title

• D06P5/30

  Ink jet printing · CPC title

• B41J2/2114

  Ejecting specialized liquids, e.g. transparent or processing liquids (B41J2/211 takes precedence) · CPC title

• B41J2/2121 Primary

  characterised by dot size, e.g. combinations of printed dots of different diameter · CPC title

• B41M5/0017

  Application of ink-fixing material, e.g. mordant, precipitating agent, on the substrate prior to printing, e.g. by ink-jet printing, coating or spraying · CPC title