JPH04185344A - Image forming material - Google Patents

Abstract

PURPOSE:To reduce the viscosity of an image forming material and improve its fluidity by dissolving polyacrylamide in a solvent constituting the image forming material. CONSTITUTION:In an image forming material that is used for an image forming device for forming an image by discharging and transferring liquid droplets from an orifice in accordance with recording marks, polyacrylamide is dissolved in a solvent constituting said image forming material. By using this image forming material, it becomes possible to reduce energy necessary for the discharge of the liquid droplets and enhance high-speed response characteristics of the discharge of the liquid droplets. Furthermore, the image forming material contains a coloring agent and, as necessary, a moisture-proofing agent, a mildew- proofing agent and the like may be added to the image forming material. It is also preferable that the amount of polyacrylamide to be added to the solvent is not more than 5wt.%, based on the weight of the image forming material.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image forming material used in an image forming apparatus that forms an image by ejecting and flying droplets from an orifice.

[Prior Art] Conventional image forming apparatuses (forming an image by ejecting and flying droplets of image forming material from an orifice) include, for example, Japanese Patent Publication No. 56-9429, Japanese Patent Publication No. 60-8953,
JP-A-54-59936, JP-A-54-109843,
USP-3946398, and image forming materials used in the image forming apparatus include, for example, Japanese Patent Publication No. 60-40474, Japanese Patent Publication No. 61-36876, Japanese Patent Publication No. 6
2-15594, JP-A-58-176255, JP-A-6
A large number of patents have been disclosed, such as No. 3-108087 and USP-4810292.

[Problem to be solved by the invention] In a conventional image forming material (used in an image forming apparatus that forms an image by ejecting droplets from an orifice in response to a recording signal), droplets eject from an orifice. The viscosity of the image-forming material is adjusted to enable ejection flight, to further reduce the energy required to eject a droplet from an orifice, or to provide a faster response for ejecting a droplet from an orifice. needs to be kept extremely low.

In conventional image forming materials, low viscosity is achieved by minimizing the amount of colorants and other additives that make up the image forming material, or by adding low viscosity liquids such as N-methylpyrrolidone. We have been producing image-forming materials, but reducing the viscosity of image-forming materials using such technology is
This is considered to be almost at its limit at present, and therefore it is considered extremely difficult to reduce the energy required to eject droplets from the orifice and improve the high-speed response of droplet ejection from the orifice using conventional image forming materials. .

The present invention is intended to solve these problems, and its purpose is to provide an image forming material for use in an image forming apparatus that forms an image by ejecting and flying droplets from an orifice in response to a recording signal. The objective is to provide an image forming material that has extremely low viscosity and good fluidity.

[Means for Solving the Problems] The image forming material of the present invention is an image forming material used in an image forming apparatus that forms an image by ejecting and flying droplets from an orifice in response to a recording signal. It is characterized by the fact that vocacrylamide is dissolved in the solvent that makes up the material.

[Function] According to the above configuration of the present invention, by dissolving polyacrylamide in the solvent constituting the image forming material,
The generation of turbulence that occurs at the contact portion between the image forming material and the tube wall is suppressed, energy loss is reduced, and the apparent viscosity of the image forming material is reduced.

Hereinafter, the present invention will be explained in detail with reference to Examples.

[Example] The image forming material of the present invention is composed of a solvent, a colorant, and polyacrylamide, and if necessary, a humectant,
Antifungal agents are added.

The amount of polyacrylamide added is preferably 5 wt % or less in the image forming material.

Further, FIG. 1 shows an outline of an image forming material discharge mechanism (head for an inkjet printer) in an embodiment of the present invention. 1 in the figure is an image forming material, 2 in the figure is an orifice,
3 in the figure is a nozzle, 4 in the figure is a cavity, 5 in the figure is a piezo vibrator attached to the side of the cavity 4, 10 in the figure
are droplets of the image forming material 1 discharged from the orifice 2, and droplets 10 of the image forming material 1 are discharged from the orifice 2 by mechanically vibrating the piezo vibrator 5 in accordance with the recording signal.

Example 1 In this example, solvent: water 95 wt%, colorant: water-soluble black dye 4 wt%, polyacrylamide
An image forming material composed of 1 wt% was prepared.

The viscosity of the image forming material in this example was 1°7 mPa.
-5.

When droplets of the image forming material in this example were ejected by the image forming material ejecting mechanism shown in FIG. Droplets were ejected and flew.

Example 2 In this example, solvent: water 91 wt%, colorant:
Water-soluble black dye 4wt%, polyacrylamide 5w
An imaging material consisting of t% was prepared.

The viscosity of the image forming material in this example was 1°8 mPa.
-5.

As in Example 1, when droplets of the image forming material in this example were ejected using the image forming material ejecting mechanism shown in FIG. 1, stable ejection flight of the droplets was achieved.

Example 3 In this example, solvent: water 90 wt%, colorant:
Water-soluble black dye 4wt%, polyacrylamide 6w
An imaging material consisting of t% was prepared.

The viscosity of the image forming material in this example was 2°0 mPa.
-5.

As in Example 1, when droplets of the image forming material in this example were ejected using the image forming material ejecting mechanism shown in FIG. 1, stable ejection flight of the droplets was achieved.

However, some satellite dots were observed due to tailing of droplets during ejection.

Comparative Example In this comparative example, solvent: 96 wt% water, colorant;
An image forming material composed of 4 wt % of a water-soluble black dye was prepared.

#The viscosity of the image forming material in this example is 2°1 mPa
-5.

When droplets of the image forming material in this comparative example were ejected using the image forming material ejecting mechanism shown in FIG. In addition, the ejected droplets were deflected in flight (due to non-uniform wetting of the image forming material 1 in the nozzle 3), and the ejection of the droplets was unstable.

Assuming that the driving frequency of the piezo vibrator 5 is 3.24 kHz and the driving voltage is 120 V, the image forming material ejecting mechanism shown in FIG. 1 can stably eject and fly the image forming material droplets in this comparative example. It was possible to do so.

"Effects of the Invention" As described above, according to the present invention, in an image forming material used in an image forming apparatus that forms an image by ejecting and flying droplets from an orifice in response to a recording signal, the image forming material By dissolving polyacrylamide in the solvent constituting the material, it is possible to reduce the energy required for ejecting droplets and improve the high-speed response of ejecting droplets.The image forming material of the present invention can be used in copying machines. It can be applied as an image forming material used in image forming apparatuses such as , printers, and fax machines.

[Brief explanation of the drawing]

FIG. 1(a) is a schematic diagram of an image forming material discharging mechanism in an embodiment of the present invention, and FIG. 1(b) is a sectional view of the image forming material discharging mechanism in a first embodiment of the present invention. 1: Image forming material 2: Orifice 3: Nozzle 4: Cavity 5 Piezo vibrator 0: Droplet or more Applicant Seiko Epson Corporation Representative Patent attorney Kizobe Suzuki (1st person in chemical engineering) (b) 1st figure

Claims (1)

[Claims] An image forming material used in an image forming apparatus that forms an image by ejecting and flying droplets from an orifice in response to a recording signal, characterized in that polyacrylamide is dissolved in a solvent constituting the image forming material. image-forming materials.